Subjects -> ENERGY (Total: 414 journals)
    - ELECTRICAL ENERGY (12 journals)
    - ENERGY (252 journals)
    - ENERGY: GENERAL (7 journals)
    - NUCLEAR ENERGY (40 journals)
    - PETROLEUM AND GAS (58 journals)
    - RENEWABLE ENERGY (45 journals)

ELECTRICAL ENERGY (12 journals)

Showing 1 - 12 of 12 Journals sorted alphabetically
CES Transactions on Electrical Machines and Systems     Open Access   (Followers: 1)
CPSS Transactions on Power Electronics and Applications     Open Access   (Followers: 3)
CSEE Journal of Power and Energy Systems     Open Access   (Followers: 1)
Electrical Engineering and Power Engineering     Open Access   (Followers: 3)
Electrochemical Energy Reviews     Hybrid Journal   (Followers: 3)
IEEE Open Journal of Power Electronics     Open Access   (Followers: 11)
IEEE Power and Energy Technology Systems Journal     Open Access   (Followers: 4)
IEEE Transactions on Transportation Electrification     Hybrid Journal   (Followers: 3)
Journal of Microwave Power and Electromagnetic Energy     Hybrid Journal   (Followers: 3)
Journal of Power Electronics     Hybrid Journal   (Followers: 6)
Journal of Power Sources Advances     Open Access   (Followers: 1)
KnE Energy     Open Access  
Similar Journals
Journal Cover
IEEE Transactions on Transportation Electrification
Number of Followers: 3  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Online) 2332-7782
Published by IEEE Homepage  [228 journals]
  • IEEE Transactions on Transportation Electrification

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      Abstract: Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • IEEE T T E Special Issue on Electrified Aircraft
           Technologies

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      Authors: Kiruba Sivasubramaniam Haran;
      Pages: 4033 - 4036
      Abstract: Worldwide, air transportation accounts for at least 2.5% of carbon emissions, and this fraction will rise as the industry continues its rapid growth. Electrification of air transport is a vital component of global carbon reduction. The United Nations Climate Change Conference held in 2021 (COP26) set a clear goal of securing global net zero emissions by mid-century and keeping $1.5 ^{mathrm {circ }}text{C}$ global warming limit within reach. The development and implementation of energy-efficient advanced technologies with reduced environmental impact is of critical importance. It is predicted that by 2050, energy use and carbon emissions of the transportation industry will increase by 80% over present levels if there is no concerted action to mitigate this. The Intergovernmental Panel on Climate Change has set the target of at least 50% reduction of CO2 emissions by 2050. Leaders at the COP26 summit signed an agreement committed to supporting the adoption by UN’s International Civil Aviation Organization (ICAO) of an “ambitious long-term aspirational goal that is compatible with net-zero global emission by 2050.” Achievement of these strategic goals requires fundamental reconsideration of aircraft engineering and propulsion, which have not really changed since the 1950s.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Components of Electrical Power Systems in More and All-Electric Aircraft:
           A Review

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      Authors: Ashkan Barzkar;Mona Ghassemi;
      Pages: 4037 - 4053
      Abstract: Even though achieving carbon-free and reduced NOx emission transportation is a prevailing goal, the aviation industry is in its infancy to arrive at passenger class all-electric aircraft (AEA) properly operating over commercial missions. Challenges are mainly associated with the components of the aircraft electric power system (EPS). Considering today’s technologies, power electronics components are not capable to sustain tens of megawatts of required power during the takeoff and meet the aviation limits in terms of size, weight, and cost at the same time. The state-of-the-art electrochemical energy units (EEUs), including battery, fuel cell, and supercapacitor, cannot provide the 25–30-MW thrust power needed for the takeoff, and electrical circuit breakers (CBs) are not able to clear a fault in a large AEA propulsion system, and multimegawatt electric drives/motors can barely be found being able to provide 2–3-MW thrust power, so that they can be employed in a distributed propulsion architecture. Taking mentioned challenges into account, this article aims to tackle challenges associated with protection devices, EEUs, and electric machines in passenger class AEA and present promising solutions using an envisioned medium voltage direct current ±5-kV EPS for an AEA, all-electric NASA N3-X aircraft. Based on findings and discussions made through this article, the authors conclude that although technology advancements are essential in all research areas, high-voltage wide bandgap electrical CBs, Li-air and Li-S batteries with >1000-kW/kg specific power, and multimegawatt superconducting electric machines will turn a commercialized passenger class AEA into reality within the next 20–30 years.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Benefits of Parallel Hybrid Electric Propulsion for Transport Aircraft

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      Authors: Dalton P. Decerio;David K. Hall;
      Pages: 4054 - 4066
      Abstract: As battery and electric machine technologies improve, the electrification of aircraft propulsion systems may have the potential to reduce the energy consumption and emissions of transport aircraft. Incorporating electrical components adds a dimension to the propulsion system design space and introduces new tradeoffs between weight and efficiency. In this article, we apply numerical optimization to the conceptual design of regional transport category airplanes to quantify the energy efficiency benefits of parallel hybrid electric propulsion, identify the mechanisms of the benefits, and characterize the scaling effects of design parameters such as range and electrical technology parameters such as battery specific energy. The results show that the state-of-the-art technology may provide energy savings up to 1%–8% over conventional turboprop engines, while projected improvements in electric technology may allow greater savings of up to 14%, albeit at a reduced range relative to conventional gas turbine-powered aircraft. By supplementing the gas turbine engine with electrical power in high-thrust conditions, the overall efficiency of the propulsion system can be improved throughout the mission. Improvements in battery specific energy and power electronics specific power are identified as enablers for efficient hybrid electric aircraft propulsion.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Aircraft Distributed Electric Propulsion Technologies—A Review

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      Authors: Majid T. Fard;JiangBiao He;Hao Huang;Yue Cao;
      Pages: 4067 - 4090
      Abstract: Global transportation has shifted toward electromobility to achieve net-zero emission, and in the next few decades, commercial electric aircraft is likely to become a reality. This transition has embarked on through the existing more electric aircraft (MEA), and the ultimate goal will be potentially achieved by hybrid-electric and all-electric airliners, along with green fuels, such as green hydrogen or supercritical CO2 (sCO2) and its potential Gg CO2 equivalent elimination—with or without combustion. Electric propulsion replaces conventional jet propulsors with electric fans powered by electric generators rotated by an engine, a combination of generators and energy storage, or just energy storage. An appealing idea is to distribute the electric fans along the aircraft wings or tails to improve aerodynamics, boost energy efficiency, and reduce carbon emissions and acoustic noise. Focusing on distributed electric propulsion (DEP) systems, this article reviews the state-of-the-art advancements in aircraft electrification. Three major DEP categories, i.e., turboelectric, hybrid-electric, and all-electric propulsion technologies, are investigated. Although all of them utilize electric fans as propulsors, their system structures and power generation stages are different. Hence, comprehensive considerations are required to optimize the DEP system designs. Starting with the multifarious electrical system architectures proposed in the literature, a thorough review is conducted including the system parametric specifications, design considerations of power converters, the power electronics devices’ characteristics in cryogenic conditions, and various energy storage systems. This review aims to provide a reference to researchers, engineers, and policy-makers in aviation to accelerate the progress toward future net-zero emissions.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • All-Electric NASA N3-X Aircraft Electric Power Systems

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      Authors: Mona Ghassemi;Ashkan Barzkar;Mohammadreza Saghafi;
      Pages: 4091 - 4104
      Abstract: In this article, turboelectric NASA N3-X aircraft is fully electrified for the first time; engines are removed and the all-electric NASA N3-X aircraft electric power system (EPS) is introduced, supplied by four electrochemical energy units (EEUs), including batteries, fuel cells, and supercapacitors. In this regard, three medium-voltage direct current (MVdc), ±5 kVdc, bipolar EPS architectures are proposed for the aircraft and discussed and analyzed in detail by a performing power flow (PF) analysis. The proposed architectures are also considered as three-phase ac, 10 kVac, EPSs and discussed and analyzed in detail for comparison. To perform the PF analysis for the proposed MVdc EPSs, two PF solvers for dc networks under constant power generations and loads are also modified and developed. Potential cable conductors are selected and hints are provided to choose final conductors; to assess the performance of selected conductors, dimensions of the aircraft are estimated and cable parameters are calculated based on the presented dimensions. The proposed EPS architectures meet power system planning criteria under normal condition as well as all n −1 contingencies. This article aims to assess newly designed EPSs and, therefore, assumptions are made about EEUs and propulsion motors to the extent whereby PF analysis is affected.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Flying Cars and eVTOLs—Technology Advancements, Powertrain
           Architectures, and Design

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      Authors: Niraja Swaminathan;Siddavatam Ravi Prakash Reddy;Kaushik RajaShekara;Kiruba S. Haran;
      Pages: 4105 - 4117
      Abstract: Flying cars and electric vertical takeoff and landing (eVTOL) aircraft could become the future of personal transportation and taxis, which would significantly reduce greenhouse gas emissions. Presently, over 250 companies are developing flying cars and eVTOLs, and at least a few vehicles are expected to be commercialized soon. This article presents the current trends and technology of VTOL flight mechanisms and identifies the vehicles in each category to evaluate their advantages and limitations. Most of the flying cars that are being developed do not have VTOL capability because of the requirement for high power during takeoff/landing for a roadworthy vehicle. This article proposes the powertrain architectures for incorporating VTOL capability for flying cars based on dual power sources, such as fuel cells and batteries. Besides, possibilities of using a single propulsion system for both drive and flight modes are explored. General design guidelines are presented for the proposed powertrain architecture to estimate the maximum takeoff weight (MTOW), power/energy demands, and source capacities. Furthermore, the technologies of the powertrain components, such as electric motors and power converters, are also discussed in this article.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • A Comprehensive Review on Fuel Cell UAV Key Technologies: Propulsion
           System, Management Strategy, and Design Procedure

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      Authors: Liangcai Xu;Yigeng Huangfu;Rui Ma;Renyou Xie;Ziyou Song;Dongdong Zhao;Yongheng Yang;Yupeng Wang;Liangfei Xu;
      Pages: 4118 - 4139
      Abstract: Unmanned aerial vehicles (UAVs) can be regarded as one of the most emerging technologies. Compared with piloted aerial vehicles, UAVs qualify for higher safety and lower cost, and they are more suitable for dangerous missions. Recently, fuel cell (FC) UAVs have obtained more and more attention due to their relatively higher energy density. However, their propulsion system still needs to be further improved to meet different requirements of performing difficult tasks. This article aims to give a comprehensive review of the key technologies of FC UAVs. First, various architectures of the propulsion system and corresponding advantages and disadvantages are introduced. Then, three kinds of management strategies for FC UAVs are reviewed. Next, some special applications and considered design procedures are summarized. Compared with other review articles, this article tries to cover more aspects of FC UAVs. Since these aspects have a tight relationship with each other, giving a comprehensive review can be more beneficial to us to understand the state-of-the-art development of propulsion systems for FC UAVs. The conclusions show that advanced propulsion architectures, efficient online energy management strategies, and professional design procedures are still in urgent demand in the commercial process of FC UAVs.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Dynamic Modeling and Rule-Based Control Design for a Hybrid-Electrified
           Regional Aircraft

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      Authors: Morteza Montazeri-Gh;Masoud Khasheinejad;
      Pages: 4140 - 4147
      Abstract: Modeling and control of hybrid-electric propulsion systems (HEPSs) is a challenging area, in particular for regional aircraft. In this research, modeling and rule-based control design for a hybrid-electrified aircraft are presented. For this purpose, real data from the ATR 42-600 as well as the modified CT7-9 turboprop engine, commercial electric machines, and battery experimental characteristics have been used to size a new version of hybrid-electric regional aircraft. Based on the dynamic modeling of HEPS, practical controllers are then designed for the turboprop engine and electric machines. It should be noted that one of the critical tasks of the control strategy for hybrid-electric propulsion is to ensure the aircraft’s safe landing. In this study, a rule-based tunable regulator is proposed to modify the conventional optimal control strategy to achieve the aircraft’s required performance over a real flight mission, in particular, to fulfill the safe landing of aircraft using the remaining battery state of charge (SOC) in the event of all-turbine failure. Finally, the results are presented to demonstrate that the proposed approach is effective for minimizing the HEPS fuel consumption, where the aircraft operational constraints, such as battery SOC and turbine overtemperature, are fulfilled at different phases of the flight mission.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Mild Hybridization of Turboprop Engine With High-Power-Density Integrated
           Electric Drives

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      Authors: Yuzheng Chen;Tao Yang;Muhammad Raza Khowja;Antonino La Rocca;Usman Nasir;Shajjad Chowdhury;Dean Evans;Dafydd Kember;Thomas Klonowski;Yohan Arnaud;Lucie Apostin;Thierry Liger;Grégory Cossart;Gaurang Vakil;Chris Gerada;Serhiy Bozhko;Sebastien Detry;Christophe Diette;Patrick Wheeler;
      Pages: 4148 - 4162
      Abstract: This article shares with the aerospace community a case study of turboprop mild hybridization using a recently developed integrated drive system in the University of Nottingham, U.K., within the ACHIEVE project under EU H2020 CleanSky 2 program (project No. 737814). The developed drive system enables the green taxiing of a turboprop aircraft while on the ground with its engine OFF and as an electrical generator when the turboprop is in the air. The entire system is designed to be able to integrate within the power auxiliary gearbox (PAGB) of a turboprop aircraft. Some of the key features of the developed system include a high-speed permanent magnet machine (up to 14200 rpm) with a dual-three-phase design, silicon carbide (SiC)-based high power density (11.8 kW/L for the power converter, and 35.3 kW/L and 7.2 kW/kg for the machine active parts), integrated cooling design for high-temperature operation ( $>130~^{circ }text{C}$ ambient temperature), fault tolerance consideration with dual-channel operation capabilities, and sensorless control for entire operational conditions. This article is giving an overview of the design process of the electrical machine, power converters, and the cooling of the entire drive. The numerical analysis [finite element method (FEM) and computational fluid dynamics (CFD)] and some experimental results are presented to demonstrate the effectiveness and the desired performance of the developed integrated drive system.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Aerodynamic Force Control for Tilt-Wing eVTOL Using Airflow Vector
           Estimation

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      Authors: Kentaro Yokota;Hiroshi Fujimoto;
      Pages: 4163 - 4172
      Abstract: Research and development are active in electric vertical takeoff and landing (eVTOL) aircraft. In particular, tilt-wing eVTOL aircraft receives much attention as one of the most efficient configurations; however, they are likely to be unstable during the transition from hover to cruise because the lift and thrust have limitations depending on the airflow and tilt angle. This study proposes a new aerodynamic force control method using airflow vector estimation. The airflow vector is estimated by combining motor current, rotational speed, and Pitot-tube measurements. Aerodynamic force control is achieved through the proper design of a feedback controller using disturbance observers (DOBs) to cope with propeller-wing interference caused by the propeller slipstream. This method takes advantage of the motor control performance and is unique in which it monitors the airflow vector and actively changes the tilt angle to quickly obtain the desired acceleration. The effectiveness of the method is verified via simulations and experiments in a wind tunnel.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Fault Tolerant Control of Advanced Power Generation Center for
           More-Electric Aircraft Applications

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      Authors: Xiaoyu Lang;Tao Yang;Zhenyu Wang;Cheng Wang;Serhiy Bozhko;Patrick Wheeler;
      Pages: 4173 - 4189
      Abstract: This article presents a control scheme for a recently reported aircraft advanced power generation center (APGC) during postfault operation conditions. Within the APGC, two electrical generators extract power from two separate engine shafts and supply electrical power to a common high-voltage direct current (HVDC) bus through their dedicated main ac/dc power converters. An extra back-to-back (BTB) converter is also used to connect the ac terminals of the two generators. This architecture provides merits of fault tolerance capabilities of the APGC. In the case of main ac/dc power converter failure, the system can be reconfigured and the BTB converter provides an extra power flow path from the generators to the HVDC bus. This ensures electrical power generation capabilities onboard. This article discusses in detail about the control of the APGC under fault conditions with one main ac/dc converter failure. A seamless transition scheme from normal operation to postfault conditions is proposed using a voltage command initialization technique within the BTB converter. Both experimental and simulation results have verified the fault tolerance improvement and control performances of the APGC.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Desensitized Optimal Control of Electric Aircraft Subject to
           Electrical–Thermal Constraints

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      Authors: Mingkai Wang;Saulo O. D. Luiz;Shuguang Zhang;Antonio M. N. Lima;
      Pages: 4190 - 4204
      Abstract: This article proposes a desensitized optimal control (DOC) methodology to enhance the trajectory robustness of electric aircraft. First, a comprehensive multiphysics model of electric aircraft is built based on the first principle. An emphasis is put on the battery pack characteristics led by the cell unevenness. Thereafter, the optimal control technique is applied to study the influence of thermal effects and battery unevenness on flight performance. Furthermore, to alleviate the impact of cell unevenness, the crude control scheme is augmented by DOC. The proposed method generates a more robust reference trajectory for aircraft against cell unevenness. Processor-in-the-loop tests prove that the trajectory is trackable via a tracking controller. Compared to the standard trajectory optimization and nonlinear model predictive control, the proposed method significantly reduces the sensitivity of battery pack temperature regarding cell unevenness with acceptable computational effort.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Efficiency Focused Energy Management Strategy Based on Optimal Droop Gain
           Design for More Electric Aircraft

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      Authors: Mohamed A. A. Mohamed;Seang Shen Yeoh;Jason A. Atkin;Habibu Hussaini;Serhiy Bozhko;
      Pages: 4205 - 4218
      Abstract: Due to the substantial increase in the number of electrically driven systems onboard more electric aircraft (MEA), the onboard electric power systems (EPSs) are becoming more and more complex. Therefore, there is a need to develop a control strategy to manage the overall EPS energy flow and ensure the operation of safety-critical systems (which are electrical loads) under different operating scenarios and to consider EPS losses minimization, exploiting the thermal capability of generators, different load priorities, and available batteries with their charging and discharging schedules. This article presents an energy management (EM) strategy that considers the aforementioned objectives. The optimal droop gain approach is employed as a power-sharing method to minimize the total EPS losses in MEA. A finite state machine (FSM) has been used to implement the control strategy to realize the EPS reconfiguration operation. The proposed EM strategy is implemented and simulated using MATLAB/Simulink and hardware-in-the-loop (HIL) under different operational scenarios, such as normal operations, failure of one of the power generation channels, and failure of all power generation channels. The proposed EM method has shown its capability to efficiently manage the EPS under different operating conditions to reduce the overall system losses.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Algorithm for the Optimal Design of a Fault-Tolerant Aircraft Power
           Transmission Network

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      Authors: Marta Zárraga-Rodríguez;Xabier Insausti;Fermín Rodríguez Lalanne;Javier Velasco;Jesús Gutiérrez-Gutiérrez;
      Pages: 4219 - 4228
      Abstract: Aircraft manufacturers aim to decrease the fuel consumption based on reducing weight and increasing the subsystem efficiency. Hence, the electric power system (EPS) acquires great relevance because it must be efficient and lightweight. Any change in the EPS must not affect the aircraft’s electrical safety, which under a traditional decentralized EPS strategy is ensured by redundancy. Recently, several decentralized EPS strategies based on the introduction of multiport power converters have arisen. Such strategies meet the established safety goals since the aforementioned devices make it possible to recalculate the path to continue powering the loads in case of failure. However, the literature does not address how to connect such multiport power converters. The main contribution of this article is to present a low-complexity algorithm that minimizing the redundancy of wiring, provides a fault-tolerant power transmission network. This is done under a decentralized EPS strategy where multiport power converters are used. The proposed strategy is evaluated on Boeing 787 aircraft, where we compare the length of the cables both under a traditional decentralized network configuration (where the redundancy option is used to ensure the safety of operation) and in the network provided by our algorithm. A saving of 66.6% is obtained.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Active Disturbance Rejection Control of DC-Bus Voltages Within a
           High-Speed Aircraft Electric Starter/Generator System

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      Authors: Xiaoyu Lang;Tao Yang;Ge Bai;Serhiy Bozhko;Patrick Wheeler;
      Pages: 4229 - 4241
      Abstract: Wide-speed range operation capabilities in both motoring and generation modes are essential for an aircraft electrical starter/generator (ESG) drive system for more-electric aircraft applications. When running as a generator, the ESG is supplying power to the main HVdc bus within the onboard electrical system. A fast and robust dc bus voltage would be beneficial to electrical loads connected to it. In this article, an active disturbance rejection control (ADRC) is proposed to realize a fast and robust regulation of onboard dc bus voltages. The ADRC is achieved with a second-order extended state observer (ESO) to generate torque reference for the ESG. All the key characteristics, such as the stability of ESO, dc voltage tracking performance, and disturbance rejection capability of the ADRC for aircraft ESG applications, are thoroughly analyzed. To enhance system stabilities, an innovative and simple design method for the ADRC and ESO gains is introduced based on the gain-margin and phase-margin criteria. Experimental results have shown that, compared with the conventional PI-based dc voltage control, the proposed method can realize a faster and more robust dc voltage control.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Multidisciplinary Design Overview and Comparison for Two Case Studies of
           High Speed Permanent Magnet Machines

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      Authors: Ziyuan Huang;Zhongya Ding;Maotong Pang;Baodong Chen;
      Pages: 4242 - 4254
      Abstract: High-speed electrical machines have become more and more popular applications driven by electric vehicles and all-electric aircraft. Their design usually requires a high level of integration, including loss, thermal, cooling, and mechanical aspects. This article makes a comprehensive overview of the multidiscipline design method of high-speed permanent magnet (HSPM) machines. A 4-kW machine with the flexible rotor operating above the first bending critical speed is presented, and a 30-kW machine is also developed with consideration of the multidisciplinary design process for contrast. The constraint and the mechanism in the overview are investigated to clarify the influence of different design variables on the rotor structure and performance. Finally, two machines are fabricated and tested, and the values are compared with theoretical results.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Design and Analysis of Dual Stator PMSM With Separately Controlled Dual
           Three-Phase Winding for eVTOL Propulsion

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      Authors: Sung-Woo Hwang;Dong-Kyun Son;Soo-Hwan Park;Geun-Ho Lee;Young-Doo Yoon;Myung-Seop Lim;
      Pages: 4255 - 4264
      Abstract: The propulsion system of the electric-powered vertical take-off and landing aircraft requires a high level of performances, including power density, efficiency, noise vibration and harshness, and fault tolerance. Among many types of conventional electric motor, the outer rotor surface-mounted permanent magnet synchronous motor (SPMSM) is widely used for its high power density and low torque pulsation. However, these advantages are degraded when the multiphase winding is applied to secure the fault-tolerance characteristics. To overcome the limit of conventional motor topology, the dual stator permanent magnet synchronous motor with separately controlled dual three-phase winding is proposed. The advantages of the proposed topology are resulted from the feature of mechanical, electrical, and magnetic isolation. To maximize the distinctive feature, a design process considering separated current vector control (SCVC) method is established. A design example is presented to demonstrate the impacts of the proposed design process considering SCVC on the power density maximization, torque harmonic reduction, and efficiency improvement. Finally, the experimental verification is presented to validate the proposed design and control techniques.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Convective Heat Transfer Characteristics on End-Winding of Stator Immersed
           Oil-Cooled Electrical Machines for Aerospace Applications

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      Authors: Runyu Wang;Xinggang Fan;Dawei Li;Ronghai Qu;Lei Li;Tianjie Zou;
      Pages: 4265 - 4278
      Abstract: The stator immersed oil cooling has emerged as a promising thermal management method for high power density electric machines applied in aerospace applications. However, due to the complex geometry of end-winding, the research on the convective heat transfer coefficient (CHTC) for the flooded stator is still at infancy. This article investigates the convective heat transfer characteristics on end-winding of stator immersed oil-cooled electrical machines by computational fluid dynamics (CFD) methods and experiments implemented on a motorette. The variation law of the CHTCs of end-winding with flow rate is thoroughly investigated. Subsequently, new dimensionless correlations are defined using Nusselt numbers as a function of Reynolds numbers, which are further applied into a detailed lumped-parameter thermal network (LPTN) for rapid evaluation of temperature distribution. Finally, the obtained simulation results are verified by local temperature measurements. The experimental results also show that the proposed stator immersed oil-cooled structure can withstand a current density of up to 30 A/mm2 with a corresponding continuous power density of 6.8 kW/kg.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Design and Demonstration of a 100 kW High-Frequency Matrix Core
           Transformer for More Electric Aircraft Power Distribution

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      Authors: Zhe Zhao;Yuheng Wu;Fei Diao;Nan Lin;Xinyuan Du;Yue Zhao;Guangqi Zhu;
      Pages: 4279 - 4290
      Abstract: The rapid development of more electric aircraft (MEA) raises the demand for high-power converters with significant weight and volume reduction for onboard power distribution. The isolated dc/dc converter using the medium-frequency transformer (MFT) is a feasible solution. To design an MFT with improved electromagnetic and thermal performance, a matrix core transformer (MCT) architecture is proposed with accurate models in this article. With superior heat dissipation ability, the high current windings can be effectively cooled with both natural and forced air convection. In addition, an optimization methodology for MCT design is presented. As a result, the prototype of a 100-kW, 50-kHz MCT with an additive manufactured bobbin is built. The results of both finite element analysis (FEA) simulation and experimental study in a full power dual active bridge (DAB) with the MCT prototype are presented to verify the theoretical design. The power density and efficiency of the MCT reach 17.7 kW/L and 99.63%, respectively.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • A Low Inductance, High Power Density 3L-TNPC Power Module for
           More-Electric Aircraft Applications

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      Authors: Zhao Yuan;Asif Imran Emon;Zhongjing Wang;Yang Li;Yalin Wang;Fang Luo;
      Pages: 4291 - 4302
      Abstract: Three-level T-type neutral-point-clamped converters (3L-TNPCs) are widely used in propulsion converters in more-electric aircraft (MEA) applications as higher efficiency, improved output total harmonic distortion (THD), and lower common-mode noise. However, such topology suffers from high stray inductance because of complicated power loop. Its power module current density is also less than the two-level (2L) converter as the increased switch counts. To solve the issue, this article proposes a novel hybrid-structure-based full SiC-MOSFET 3L-TNPC power module. The module has a printed circuit board (PCB) stacked on top of the substrate, with bare dies soldered on direct bond copper (DBC) and connected to PCB by bonding wires. Such a structure allows the power loop on both the substrate and PCB. This reduces the stray inductance by enhanced mutual inductance cancellation. The heat from dies can be directly dissipated through the substrate and the proposed base-plate-embedded cooling system, enhancing thermal conductivity by 55%. Based on the structure, a 1.2-kV, 300-A 3L-TNPC module is fabricated with a stray inductance of 2.5 nH. Because the stray inductance is 68% smaller than a state-of-the-art module, faster driving speeds can be used with limited voltage overshoots. As a result, the switching loss of the module is reduced by 62.5% compared with the same bare die at a state-of-the-art module’s power loop at 800 V, 450 A. Eventually, impedance characterization by impedance analyzer, double-pulse tests, and continuous tests are performed for experiment evaluation.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • A Simplified Analytical Approach for Hybrid Exciters of Wound-Field
           Generators

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      Authors: Giampaolo Devito;Stefano Nuzzo;Davide Barater;Giovanni Franceschini;
      Pages: 4303 - 4312
      Abstract: Midpower wound-field generators are predominantly used for grid applications, marine naval ships, industrial buildings, and critical standby power applications. They are often equipped with brushless excitation systems (ESs), where an exciter supplies the generator through a diode rectifier. Here, the uncontrolled nature of the rectification process can determine a significant reduction of the mean value of the output voltage. Hence, the root causes must be identified and properly modeled for an accurate evaluation of the system performance. In this article, a simplified analytical model is proposed for such purposes, taking as case study a consequent-pole, hybrid exciter of a wound-field generator for naval applications. The approach is based on the calculation of the diodes’ commutation angle, which permits to estimate the exciter’s armature current waveforms. Special focus is given to the voltage waveforms, which are determined using the estimated current waveforms as an input, thus removing the need for a numerical resolution. In addition, simplified equivalent functions calculated without relying upon finite-element (FE) analyses are employed to determine the machine inductances. Being fully released from any numerical computation, the proposed model permits a fast but accurate evaluation of the exciter performance. For validation purposes, FE and experimental investigations are finally performed.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Additively Manufactured Ultralight Shaped-Profile Windings for HF
           Electrical Machines and Weight-Sensitive Applications

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      Authors: Ahmed Selema;Mohamed N. Ibrahim;Peter Sergeant;
      Pages: 4313 - 4324
      Abstract: Nowadays, additive manufacturing (AM) is becoming a more feasible solution for scalable electric drives compared to traditional production systems. Also, with the significantly growing automotive sector, innovation in electric machine technology is evolving rapidly. With the unmatched freedom in geometry, AM offers a great deal of flexibility in the design of electrical machine parts. Not only the passive parts can be printed such as the frame and the shaft of the electrical machine, but also active parts, such as windings, can be printed in lightweight materials such as Al–Si–Mg-based alloy. The main focus of this article is to further utilize AM in the design of electrical machine windings, with low weight and low losses especially at high-frequency (HF) operation. Aiming at HF loss reduction, different AM coils are prototyped using different materials, and their performance is compared with traditionally manufactured coils. Moreover, a new design concept of shaped-profile conductors is presented with reduced proximity effect and less impact by the cross-slot leakage flux. This design combines high electromagnetic performance and ultralightweight merits, allowing for higher power density electrical machines.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Analysis of the Flux Density and Back EMF in Eccentric Permanent Magnet
           Machines Based on 2-D Air-Gap Modulation Theory

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      Authors: Hengliang Zhang;Yuchen Wang;Wei Hua;David Gerada;Ming Cheng;
      Pages: 4325 - 4336
      Abstract: In this article, the unified 2-D air-gap field modulation (AFM) model is established to analyze the flux density and back electromagnetic force (EMF) in both rotor-permanent magnet (PM) and stator-PM machines under eccentricity. For the temporal distribution of flux density, the static eccentricity (SE) causes amplitude unbalance, while the dynamic eccentricity (DE) leads to sideband harmonic components. The sideband harmonic is commonly regarded as a double-sideband (DSB) modulation effect, but it may be a single sideband (SSB) modulation effect in some specific cases, which is analytically and experimentally proved in this article. More importantly, a quantitative description of how eccentricity influences the phase back EMF is provided, which is only qualitatively expressed in the existing literature. A standardized analysis process is also given, which can be used for different machine topologies. The aforementioned conclusions are validated by the simulations and experiments on two prototyped machines, namely, an 18-slot 20-pole (18s/20p) surface-mounted PM (SPM) machine and a 12s/10p flux-switching PM (FSPM) machine.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Optimization of Stator Slot Parameters for Electromagnetic Vibration
           Reduction of Permanent Magnet Synchronous Motors

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      Authors: Zezhi Xing;Xiuhe Wang;Wenliang Zhao;
      Pages: 4337 - 4347
      Abstract: Slight electromagnetic vibration is one of the crucial indicators that must be considered in the motor design stage. Considering the influence of complex stator slot structure and inevitable saturation at slot opening, a permeance calculation model suitable for the motor with any pole-slot combination is introduced, and the electromagnetic force waves of the motor are calculated quickly and accurately. Considering the orthogonality of stator material and the influence of enclosure and windings, the natural frequencies of the entire stator are analyzed, and the vibration accelerations are calculated by the multiphysics model including control, electromagnetic, structural, and vibration models, the accuracy of the calculation results is verified by the prototype test. Furthermore, the components of electromagnetic force waves that have great impact on electromagnetic vibration are summarized, a weakening method of electromagnetic vibration based on the optimization of the stator slot parameters is proposed, and the optimal stator slot parameters are obtained by the simplified model and the accurate model combining deep neural network (DNN) and immune clone algorithm (ICA), respectively. For the 6-pole 36-slot motor, the vibration accelerations near the six-order natural frequency are greatly reduced by optimizing the stator slot parameters based on the accurate model combining DNN and ICA, and the maximum vibration accelerations are reduced by 34.1% at no load and 36.8% at rated load.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Design and Multiobjective Optimization of a Double-Stator Axial Flux SRM
           With Full-Pitch Winding Configuration

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      Authors: Fengyuan Yu;Hao Chen;Wenju Yan;Vitor Fernão Pires;Joao F. A. Martins;Pavol Rafajdus;Antonino Musolino;Luca Sani;Miguel Pablo Aguirre;Muhammad Asghar Saqib;Mohamed Orabi;Xiaodong Li;
      Pages: 4348 - 4364
      Abstract: In this article, a novel axial flux double-stator switched reluctance motor (AFDSSRM) is presented and optimized for electric vehicle applications. AFDSSRM adopts the axial arrangement of double-stator and inner rotor structure with a full-pitch winding configuration. The flux generated by the two stators cancels each other at the unaligned position, and then, a low unaligned inductance barely affected by saturation is achieved, which is the primary advantage of the AFDSSRM. First, the topology and power equation of the motor are presented briefly. Due to a large number of dimensional parameters of the proposed structure, comprehensive sensitivity analysis is used to classify the design parameters into strong- and weak-sensitive classes, and a multilayer optimization approach is adopted for the variables of both classes. The response surface method combined with the multiobjective genetic algorithm is employed to optimize the strong-sensitive variables, while the Taguchi algorithm is applied to optimize the weak-sensitive variables. Moreover, the 3-D finite element model is established to analyze the electromagnetic characteristics of the motor. Finally, a prototype motor is manufactured, and the experimental results verify the effectiveness of the proposed structure and the optimization method.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Precise Control of Flat-Topped Air-Gap Magnetic Field in a Five-Phase
           Induction Machine Powered by Third-Harmonic-Injected Sinusoidal Supply

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      Authors: Haitao Liu;Dong Wang;Xinqiang Yi;Xiaoqin Zheng;Fengrui Cui;
      Pages: 4365 - 4377
      Abstract: The third-harmonic-injected sinusoidal supply (THISS) can help make an innovative breakthrough to improve the power density of multiphase induction machines. However, the existing typical control approaches cannot guarantee the machine to precisely generate the expected flat-topped air-gap magnetic field under all operating conditions, which restricts the popularization of THISS. This article first converts the control objective from generating a flat-topped air-gap field to air-gap flux linkage alignment. In conventional approaches, the rotor leakage flux linkage is not fully considered, and subjective hypothesis is proposed, resulting in the misalignment between air-gap flux linkages components with different harmonic orders. Based on avoidance of exposed flaws and correct theoretical derivation, this article focuses on the spatial distribution of air-gap field and gives priority to the alignment of the air-gap flux linkage by means of harmonic air-gap field-oriented vector control. The required third-harmonic field can be calculated in real time through the fundamental field. Therefore, the flat-topped air-gap field is ensured by fundamental and harmonic current loops. Furthermore, the controllers in fundamental and harmonic current loops are decoupling with each other. The theoretical analysis and the proposed control approach are validated by simulation and experimental results in a five-phase induction machine (FPIM) powered by THISS.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Investigation of Staggered PWM Scheme for AC Common Mode Current
           Minimization in SiC-Based Three-Phase Inverters

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      Authors: Ripun Phukan;Xingchen Zhao;Pascal Asfaux;Dong Dong;Rolando Burgos;
      Pages: 4378 - 4390
      Abstract: The advent of SiC devices which results in lower rise times and steep $text{d}v/text{d}t$ at the inverter terminal can compromise the common mode (CM)-conducted emissions’ compliance, motor peak ac -CM currents, and leakage currents. Consequently, this results in a high ac and dc side CM filter weight. AC filters at the inverter output terminal are effective in reducing the slew rate of inverter voltage thereby reducing the peak CM current. However, a special case with high $text{d}v/text{d}t$ arising from low duty cycles is found to increase the peak ac-CM current significantly. Reduced CM voltage (CMV) schemes are popular pulsewidth modulation (PWM) methods to minimize the peak CMV but suffer from high $text{d}v/text{d}t$ under this special case as well. In this article, a staggered PWM scheme to minimize such peak ac -CM currents for a high-speed variable frequency drive (VFD) is evaluated using a three-level SiC-based T-type inverter as a demonstrator. From the analysis, the proposed switching pattern shows benefits over conventional sinusoidal PWM (SPWM) scheme and is found to be scalable to other PWM schemes and voltage levels. Simulation and experimental results are shown to validate the performance of the proposed switching pattern.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Design and Optimization of Gate Driver Integrated Multichip 3-D GaN Power
           Module

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      Authors: Asif Imran Emon;Hayden Carlton;John Harris;Alexis Krone;Mustafeez Ul Hassan;Abdul Basit Mirza;Maksudul Hossain;Arman Ur Rashid;Yuxiang Chen;Fang Luo;David Huitink;Alan Mantooth;
      Pages: 4391 - 4407
      Abstract: Gallium nitride (GaN) high electron mobility transistors (HEMTs) are excellent power semiconductor devices due to their superior material properties compared to their silicon (Si) counterparts. It has demonstrated a fast switching speed with high dV/dt, enabling the designer to push the switching frequency toward the MHz range. However, traditional wire-bonded packaging becomes a limiting factor in fully harnessing the benefits offered by these advanced power devices, as it is likely to introduce voltage overshoot, oscillation, parasitic turn-on, and electromagnetic interference (EMI) issues; thus, improved and advanced packaging structures are a must to bridge the gap. Besides, the unique electrical behavior and footprint of GaN compared to Si and Si carbide make them have different requirements for power module integration. To seek a viable solution, a globally optimized double-sided cooled, gate driver integrated 650-V/60-A GaN half-bridge power module is presented herein. The proposed 3-D integrated hybrid solution delivers an optimized package, having power loop inductance and thermal resistance as low as 0.91 nH and $0.38~^{circ }text{C}$ /W, respectively, which is verified using simulation and experimental results. The overall utility of the design improved proportionately by introducing simple, yet effective electrical/thermal codesign approaches, which can be applied to future power modules, designed for separate applications.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Capacitor Energy-Based Current Sharing Control for More-Electric-Aircraft
           Onboard Microgrids With Parallel Sources

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      Authors: Yanwu Xu;Zhuoran Zhang;
      Pages: 4408 - 4417
      Abstract: A current-sharing (CS) strategy based on capacitor energy control (CEC) is proposed for more-electric-aircraft (MEA) onboard microgrids with parallel sources. In conventional sources, the reference value is the dc-link voltage, which can be corrected based on the error between the output and the average current to realize CS. However, since the source characteristics are different, each source needs a proportion-integration-differentiation (PID) controller for CS control. In the CEC-based source, the reference value is the energy stored in the dc-link capacitor. The CEC calculates the reference output current, which is the input value of the field current controller. In the proposed CS control, the reference output current is corrected by the error between the output current and the average current. Since the current values are directly added up, differences between sources are eliminated. Fewer controllers are needed and the scheme is simplified. The dynamic performance and adaptability to operating condition variations are optimized. The CS error is low and dynamic responses are accelerated. A 270- $text{V}_{mathrm {dc}}$ microgrid with parallel-connected doubly salient electromagnetic generators (DSEGs) is investigated and implemented. The CEC CS control and the conventional method are compared. The CS error, dynamic responses during connection, disconnection, speed variation, and load variation are investigated. The optimized performances of the CEC CS method are verified by experimental results.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • An Improved Three-Vector-Based Model Predictive Current Control Method for
           Surface-Mounted PMSM Drives

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      Authors: Bo Xu;Qing Jiang;Wei Ji;Shihong Ding;
      Pages: 4418 - 4430
      Abstract: The conventional model predictive control method suffers from large torque ripples and harmonic current. Moreover, the modulation range of output is limited, leading to the deterioration of performance. To address these problems, this article proposes an improved three-vector model predictive current control method for surface-mounted permanent magnet synchronous motor (SPMSM) drives. First, virtual vectors are introduced to increase the number of available voltage vectors, in which the voltage vector control set can be extended. Furthermore, a hierarchical multilevel optimization control algorithm is adopted to obtain the main control set and the extended control set. According to two different control sets, the first and second vectors can be obtained by the cost function, respectively, which can realize modulation range extension. Then, the zero vectors are added to adjust the magnitude of the output voltage vector, and the output vector action time is obtained based on the deadbeat principle. The ripples can be minimized, and the modulation range can be extended with the proposed method. Finally, a comparative analysis of both the simulation and experimental tests is investigated. The comparative investigation verifies the effectiveness and feasibility of the proposed method.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Speed/Torque Ripple Reduction of High-Speed Permanent Magnet
           Starters/Generators With Low Inductance for More Electric Aircraft
           Applications

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      Authors: Xiang Zhang;Tao Yang;Serhiy Bozhko;
      Pages: 4431 - 4443
      Abstract: With the electrification trend of future aircraft, high-speed permanent magnet starters/generators (PMSs/Gs) will potentially be widely used in onboard generation systems due to their high power density and high efficiency. However, the per-unit reactance of such high-speed machines is normally designed to be very low due to limited onboard power supply voltage and large electrical power demand, which can result in large current ripples in the machine and thus large torque ripples especially when the machine is fed with a semiconductor-based inverter of a lower switching frequency. The torque ripples may further lead to speed oscillation and generate severe vibrations and noises that are harmful to the mechanical system and human beings around. In this article, a speed/torque ripple reduction method for high-speed PMS/Gs with a low inductance is proposed to improve their performance within a wide speed range. An active damping technique is applied to the speed loop to increase the anti-disturbance capability and generate a smoother reference for the current loop, whereas an adaptive output voltage saturation limit is utilized for the current loop to limit the peak value of current to prevent overcurrent and torque spikes. The parameter tuning criteria are derived through a thorough analysis. Finally, the proposed method is validated on a high-speed PMS/G with an inductance of 99 $mu text{H}$ . The results show that the speed ripples and torque ripples are reduced by over 50% within a speed range of 2–14 krpm.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • A Hybrid Modulation Method With the Maximum Controllable Range of the
           Neutral-Point Current for Three-Level NPC

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      Authors: Zhiqiang Dong;Chenchen Wang;Qian Cheng;
      Pages: 4444 - 4455
      Abstract: In order to analyze the maximum neutral-point (NP) voltage controllability of the three-level NPC under carrier-based pulsewidth modulation, this article deduces the accurate relationship between the three degrees of freedom under carrier-based pulsewidth modulation (zero-sequence voltage, zero-level disassembly phase, and the extent of zero-level disassembled) and the NP current. Meanwhile, a hybrid method is proposed to obtain the suitable values of the three degrees of freedom that can achieve the maximum controllable range of the NP current directly. Therefore, the proposed hybrid method avoids the huge computational burden caused by the cyclic traversal method. Compared with the traditional method of injecting zero-sequence voltage or disassembling the zero level, the proposed method can realize the maximum controllability of the NP voltage under the full range of the power factor and the modulation index with a lower switching frequency. The proposed method is verified by experiments.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Synthetic Sensorless Control Scheme for Full-Speed Range of Switched
           Reluctance Machine Drives With Fault-Tolerant Capability

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      Authors: Dalin Zhou;Hao Chen;Xing Wang;Vitor Fernão Pires;João Martins;
      Pages: 4456 - 4469
      Abstract: In this article, a synthetic sensorless control scheme for full-speed range of switched reluctance machine (SRM) drives with phase absence fault-tolerant capability is proposed, which integrates the phase inductance gradient detection and the idle phase inductance threshold comparison. First, in each excitation period, only the demagnetization inductance slope negative-going zero-crossing detection (D-ISNZ) is performed to avoid the erroneous aligned position estimation in the main excitation region. Then, considering the sensitivity of the D-ISNZ method to demagnetization regions, the remedial sensorless control strategy based on single inductance threshold (SIT) is adopted. Also, the synthetic algorithm is developed for the seamless combination between the two sensorless methods. To enhance the reliability of sensorless operation, a fault-tolerant rotor position estimation method considering speed transient and phase deviation compensation is also presented. Furthermore, to ensure stable sensorless starting, a commutation instant direct estimation method based on online determined double inductance thresholds is developed. The proposed sensorless control scheme can achieve robustness operation under various working conditions without any prior knowledge of magnetic characteristics, large storage memory occupations, and intensive computations. Experiments are conducted on a three-phase 12/8 SRM experimental setup to verify the feasibility of the proposed sensorless control scheme.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • A Modified Space Vector Modulation for DC-Side Current Ripple Reduction in
           High-Frequency Link Matrix Converter

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      Authors: Jinqiu Song;Bin Duan;Xiangjie Li;Dongxiang Wan;Wenlong Ding;Chenghui Zhang;Chunshui Du;
      Pages: 4470 - 4481
      Abstract: A high-frequency link matrix converter (HFLMC) has been increasingly used in power conversion for its distinct advantages of high efficiency and compact volume. However, the conventional six-segment space vector PWM (SVPWM) scheme leads to high current ripple on the dc side and distortion on the ac side, which can inevitably destroy the battery load and decrease power quality. This article proposes a modified SVPWM scheme with dwell time and sequence compensation (MC-SVPWM) to reduce the current ripple and distortion under high modulation index conditions. The proposed MC-SVPWM allocates the vector sequence and adjusts the duration of the vector, simultaneously. First, the reasons for the current ripple and distortion under the conventional six-segment SVPWM (6S-SVPWM) scheme are analyzed in detail. The relationship between the vector duration and the dc-side current ripple is revealed. Then, the derivation process of the proposed MC-SVPWM scheme is introduced. Compared with the conventional 6S-SVPWM scheme, the dc-side current ripple is decreased greatly, and the ac-side current distortion is reduced consequently under the proposed MC-SVPWM scheme. Simulation and experimental results verify the effectiveness of the proposed modulation strategy.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • An Improved DPWM Method for Single-Phase Five-Level ANPC Converters With
           Switching Loss Reduction and Capacitor Voltage Balance

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      Authors: Zhaowen Zhong;Chunshui Du;Xiangyang Xing;Changwei Qin;Zhiyuan Chen;Xi Liu;
      Pages: 4482 - 4495
      Abstract: Neutral-point (NP) voltage and flying capacitor (FC) voltage balance, and power loss reduction are important guarantees for the stable and high-efficiency operation of single-phase five-level active neutral-point clamped (5L-ANPC) converters. However, little reports about capacitor voltage balancing with the power loss reduction have been proposed for single-phase 5L-ANPC converters. In order to obtain the above merits, an improved discontinuous pulsewidth modulation (DPWM) method with capacitor voltage balance and power loss reduction is proposed. First, an optimized common-mode voltage is injected into the modulation waves to decrease the switching loss in each switching period. In particular, the calculation of the injected common-mode voltage is based on the analysis of the deviation of the NP voltage. Hence, a fast-dynamic response of the real-time NP voltage controlling is acquired in the meantime. Besides, in order to balance the FC voltage, the weight factors of NP voltage deviation and FC voltage deviation are compared to generate the selecting signals of redundant switching states. As a result, the capacitor voltage balance and power loss reduction are realized simultaneously. Finally, the simulation and experimental results validate the correctness and feasibility of the proposed DPWM method.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Switching State Selection for Model Predictive Control Based on Genetic
           Algorithm Solution in an Indirect Matrix Converter

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      Authors: Weizhang Song;Yang Yang;Wenjing Qin;Patrick Wheeler;
      Pages: 4496 - 4508
      Abstract: Model predictive control (MPC) has emerged as a promising control scheme for power converters and motor drives. One of the major advantages of MPC is the possibility to control several system objectives with a single control law (cost function). However, the minimization selection of the cost function and its corresponding switching state is often achieved by using the enumeration method based on a simple element comparison that can lead to a local optimum solution and is time-consuming. In this article, a genetic algorithm (GA) optimum technique is applied to enable a global optimal solution to the cost function and its corresponding switching state in parallel implementation of MPC that ensures good performance in terms of the input reactive power and output current in an indirect matrix converter (IMC). Moreover, a performance comparison between using a GA and a conventional enumeration method is described. Meanwhile, a hybrid weighting factor searching method combining branch and bound algorithms with a strategy of precise searching over a small weighting range is proposed. Finally, the operation principles and validity of the proposed algorithm are analyzed and verified by using simulation and experimental results.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Robust Incremental Bayesian Learning Based Online Flux Linkage Estimation
           for PMSM Drives

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      Authors: Kaide Huang;Guodong Feng;Chunyan Lai;Narayan C. Kar;
      Pages: 4509 - 4522
      Abstract: For the permanent magnet synchronous machine (PMSM), parameter estimation can be greatly affected by the measurement uncertainty, but few efforts are made to reduce the uncertainty level for estimation performance improvement. Therefore, this article proposes an efficient and robust incremental Bayesian learning approach for PMSM parameter estimation. The measurement uncertainty is evaluated to guide the selection of informative measurements, and the estimation uncertainty is provided to indicate the confidence in using the estimated results. Specifically, a Bayesian learning strategy with a layered noise model is proposed for nonlinear flux linkage estimation. The measurement uncertainty level is estimated from the proposed Bayesian learning model, which is utilized to adaptively select the most informative data and delete the noninformative data for parameter estimation. This contributes to improving estimation accuracy and computation efficiency. Moreover, the estimation uncertainty is also determined by the proposed model, which can be used to indicate if the estimated results can be trusted and utilized in practical applications. The proposed approach is evaluated on a laboratory interior PMSM under various operating conditions.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Reliability Analysis of a Fault-Tolerant Integrated Modular Motor Drive
           for an Urban Air Mobility Aircraft Using Markov Chains

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      Authors: James A. Swanke;Thomas M. Jahns;
      Pages: 4523 - 4533
      Abstract: Electrified urban air mobility (UAM) aircraft requires catastrophic failure rates for their propulsion systems that are lower than $10^{-9}$ failures per flight hour. Electric machines and drives have been identified as limiting propulsion subsystems with failure rates in the range of $10^{-5}$ – $10^{-6}$ failures/h. Fault-tolerant (FT) machine drives offer a promising approach to improve reliability using existing technology. An FT integrated modular motor drive (IMMD) design is proposed for a quadrotor UAM application, and its estimated reliability is studied using Markov chain analysis. Quantitative examples show that raising the repair rate for the motor drive modules significantly reduces the IMMD’s catastrophic failure rate. However, the lower bound on its failure rate with high repair rates is determined by its single-point failure (SPF) rate (e.g., motor bearings), highlighting the importance of aggressively suppressing as many of the IMMD’s SPFs as possible. Markov chain analysis shows that SPF suppression can result in major reductions in the IMMD catastrophic failure rate by factors exceeding $10^{3}$ as the SPF rate is driven toward its ideal limit value of zero.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Neutral Voltage Modeling and Its Remediation for Five-Phase PMSMs Under
           Single-Phase Short-Circuit Fault Tolerant Control

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      Authors: Bing Tian;Jiadan Wei;Marta Molinas;Runze Lu;Quntao An;Bo Zhou;
      Pages: 4534 - 4548
      Abstract: Field-oriented control (FOC) still serves as an advanced way to control ac motors for industrial applications, as such, this technique is being expanded to the postfault operation of five-phase permanent magnet synchronous motors ( $5Phi $ -PMSMs) under phase fault conditions. Previous articles have proved that the motor’s neutral voltage (NV) oscillates over the dc-bus midpoint under a single-phase open-circuit fault (OCF), and NV remediation is needed for the successful fault-tolerant FOC. However, regarding the short-circuit faults (SCFs), neither the NV model nor its remediation is elaborated. The NV oscillates severely under SCFs, and it deserves an in-depth understanding for better making use of this faulty drive. To this end, this work establishes an NV model for a general $5Phi $ -PMSM under the single-phase SCFs, including interturn and ground SCFs, and an NV remedial rule is, therefore, provided to rectify the phase voltage modulation that forms the basis of an inverter-driven system. In addition, the presented rule requires little knowledge of the motor parameters, and it can also be very easy to implement. Finally, the experimental and simulation results confirm the validity of the presented NV model as well as its remedial method.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • A Low Coupling Fault Tolerant PMA-SynRM With Mixed-Pitch Segregated
           Windings

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      Authors: Bo Wang;Xiaobao Feng;Jiayao Bao;Wenhan Xu;Jiabin Wang;Wei Hua;Ming Cheng;Shuangxia Niu;
      Pages: 4549 - 4559
      Abstract: Mutual coupling effect between different winding modules causes undesirable effects for the fault tolerant machine drives, such as current distortion, torque ripple, and increased fault current. In this article, a mixed-pitch segregated winding configuration is presented for a triple modular fault tolerant permanent magnet (PM)-assisted synchronous reluctance machine (PMA-SynRM). It exhibits less mutual coupling effect between the different winding sets, which leads to improved fault tolerance compared to the existing full-pitched segregated windings. The mutual coupling effect is described by deriving the magnetomotive force (MMF) profile, and the fault tolerant performance improvement is proven by detailed finite-element (FE) analysis and prototyping tests in healthy and various fault conditions. The results confirm that the presented winding machine has the same healthy performance as the conventional full-pitched windings, and it operates in a more balanced manner with less current distortion and lower turn fault current. It will become a more competing candidate for the safety critical applications.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • High-Frequency Square-Wave Signal Injection Based Sensorless Fault
           Tolerant Control for Aerospace FTPMSM System in Fault Condition

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      Authors: Jinquan Xu;Hao Fang;Boyi Zhang;Hong Guo;
      Pages: 4560 - 4568
      Abstract: To enhance position detection reliability, this article proposes a new high-frequency square-wave signal injection (HFSWSI) based sensorless control for aerospace fault tolerant permanent magnet synchronous motor (FTPMSM) drives, which can be configured as the nonsimilar redundancy for a physical sensor. The novel sensorless control scheme with HFSWSI in two nonfault windings is first proposed for the FTPMSM system under each phase current independent control frame, which is free of the coordinate transformation. The HFSWSI-based position detection is then proposed for rotor position estimation via HF response currents even in phase open-circuit fault (OCF) and short-circuit fault (SCF) conditions. To enhance the dynamic performance, a novel dual-output filter is proposed for the fundamental and HF response current component extractions with almost no phase lag. To guarantee the fault tolerant performance, the optimal torque control (OTC) is utilized to ensure that the FTPMSM system generates the ripple-free torque even in fault condition. The resulting sensorless FTPMSM system has outstanding low-speed sensorless control performance both in normal and fault conditions, which is also experimentally validated on a six-phase FTPMSM platform.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Fault Diagnosis of a Rotating Rectifier in a Wound-Rotor Synchronous
           Starter/Generator in the Generation Mode

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      Authors: Chenghao Sun;Weiguo Liu;Xu Han;Ningfei Jiao;Ke Shen;Rui Wang;Shuai Mao;Kunming Wang;
      Pages: 4569 - 4582
      Abstract: Accurate and timely fault diagnosis of the rotating rectifier for a wound-rotor synchronous starter/generator is of great importance to improve system reliability. In the generation mode of the system, there is one idle stator winding of the main exciter. The terminal voltage characteristic of the idle stator winding is analyzed, and a novel fault diagnosis method for the rotating rectifier in the generation mode of the system is proposed. In this method, two feature voltages, namely the maximum peak voltage and any other peak voltage of the idle stator winding terminal voltage, are extracted through voltage sequence reconstruction to calculate the feature ratio for fault detection. The corresponding rotor position obtained by an inherent position sensor where the maximum peak voltage occurs is collected to determine the faulty diode location. The experimental results verify the feasibility and effectiveness of the proposed fault diagnosis method.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Generalized Spatial–Temporal Fault Location Method for Solid Oxide Fuel
           Cells Using LSTM and Causal Inference

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      Authors: Jingxuan Peng;Jian Huang;Chang Jiang;Yuan-Wu Xu;Xiao-Long Wu;Xi Li;
      Pages: 4583 - 4594
      Abstract: An effective fault locating method is necessary to ensure the stable and efficient operation of solid oxide fuel cells (SOFCs). There is still a lack of a common fault locating method for locating multiple faults in SOFC systems. Therefore, this article proposes a multifault spatiotemporal locating method combining long short-term memory (LSTM) artificial neural network and causal inference. This method does not rely on the SOFC mechanism model and does not require a large amount of fault data. This method has good migratory characteristics and can be used with different systems. This method first reconstructs the experimental data by LSTM and locates the fault occurrence time according to the reconstruction error. Then, the space where the fault occurred is located by the causal inference method. At the same time, multiple locating methods are compared. Finally, a performance optimization method is adopted from the system level to improve the efficiency of the system. From the comparison results, it can be seen that the scheme proposed in this article is able to locate different faults in time and space with an accuracy of 92.6%. In addition, the system efficiency can be improved by 18.7% after the corresponding optimization methods are adopted.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Flux-Based Open-Switch Fault Diagnosis and Fault Tolerance for IM Drives
           With Predictive Torque/Flux Control

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      Authors: Keting Hu;Xiangyu Meng;Zhigang Liu;Junqi Xu;Guobin Lin;Laisheng Tong;
      Pages: 4595 - 4606
      Abstract: In this article, open-switch fault diagnosis and fault tolerance are proposed for induction machine (IM) drives with predictive torque control (PTC) or predictive flux control (PFC). Different from the conventional diagnosis methods for drives with finite control set model predictive control (FCS-MPC), which are based on the current, the proposed method is based on the flux error. As a result, this method can be extended to IM drive systems with PTC or PFC. It detects the fault by computing and accumulating the error between the predicted flux from the last sampling interval and the estimated flux at the current interval. Then, the polarity of the accumulated residual is utilized to localize the fault. For the fault-tolerant method, the three-phase four-switch (TPFS) inverter is chosen as it can keep working with only four switches. To reduce the torque ripple caused by the TPFS topology, a three-vector PFC method is proposed. Hardware-in-the-loop (HIL) tests are carried out to validate the effectiveness of the proposed methods. Compared to conventional diagnosis methods, the proposed one has a much faster diagnosis speed and the three-vector PFC outperforms the one- and two-vector methods.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • An Online Condition Monitor Method for IGBT Independent of Collector
           Current

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      Authors: Shu Cheng;Yusong Hu;Chaoqun Xiang;Jiawen Liu;Xun Wu;Jun Yao;
      Pages: 4607 - 4621
      Abstract: Junction temperature monitoring and fault diagnosis of power semiconductor devices can provide critical information to ensure the reliable operation of power electronic systems. In this article, an online condition monitoring method for insulated gate bipolar transistors (IGBTs), which is not affected by the collector current, is proposed based on the Miller voltage plateau of the conduction process. The relationship between the Miller voltage plateau and the junction temperature is analyzed, and an analytical model of the Miller voltage against junction temperature is established. By using this model and the conducting-state characteristics of the device, a reverse current phase measuring strategy is proposed to decouple the influence of the collector current on the junction temperature estimation, and an online measurement circuit of the Miller voltage is designed. In addition, the characteristics of the trigger voltage under different faults are analyzed to recognize fault types. The experimental results show that the proposed method has high sensitivity and good linearity. It is proven that the proposed measurement strategy is independent of the collector current, which can accurately distinguish the fault forms of IGBTs.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Current Prediction-Based Fast Diagnosis of Electrical Faults in PMSM
           Drives

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      Authors: Yun Zhang;Yao Mao;Xueqing Wang;Zheng Wang;Dianxun Xiao;Gaoliang Fang;
      Pages: 4622 - 4632
      Abstract: Open-phase fault (OPF) and open-switch fault (OSF) are two common electrical faults in the permanent magnet synchronous machine (PMSM) drives. To locate the faults rapidly and relieve the fault damage, a current prediction-based diagnosis scheme is proposed for OPF and OSF in three-phase PMSM drives. The proposed diagnosis scheme consists of three steps, namely, determining fault occurrence, locating the faulty phase, and identifying the specific fault. The general current deviations between dq-axis predicted currents from the normal model and dq-axis feedback currents are used to determine the fault occurrence. The general current deviations between dq-axis feedback currents and dq-axis predicted currents from different faulty models are used to locate the faulty phase. Then, an intervention-based diagnosis is developed to identify the specific fault. In this way, the specific fault can be quickly located within several switching periods. Finally, the effectiveness of the proposed diagnosis scheme is verified by the experimental results.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Electrochemical Impedance Spectroscopy Based State-of-Health Estimation
           for Lithium-Ion Battery Considering Temperature and State-of-Charge Effect
           

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      Authors: Qunming Zhang;Cheng-Geng Huang;He Li;Guodong Feng;Weiwen Peng;
      Pages: 4633 - 4645
      Abstract: State of health (SOH) is critical to the efficient and reliable use of lithium-ion batteries (LIBs), especially in electric vehicle (EV) applications. Recently, electrochemical impedance spectroscopy (EIS)-based technique has been proven to be effective for SOH estimation of LIB. However, existing EIS-based methods failed to consider the impact of ambient temperature and battery state of charge (SOC), leading to the limited flexibility of these methods under dynamic environments. In this work, a novel EIS-based method is proposed for battery SOH estimation considering variations of temperature and SOC. An equivalent circuit model (ECM) is first introduced, in which the solid electrolyte interface (SEI) resistance and charge transfer resistance are employed to map their relationship with SOH under variant temperature and SOC. Subsequently, a probabilistic model, taking charge transfer resistance, temperature, and SOC as input variables, is developed for LIB SOH estimation. Experimental study indicates that the estimation error of the proposed method is around 4% when simultaneously considering the temperature and SOC effects. Moreover, the estimation error can reach 1.29% under certain conditions (e.g., 80% SOC at 30 °C). Both results of estimation error are better than the existing EIS-based methods, which indicates that the proposed method is more flexible for SOH estimation with higher precision.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • The Challenges of Reliable Dielectrics in Modern Aerospace Applications:
           The Hazard of Corona Resistant Materials

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      Authors: Alberto Rumi;Jacopo Gabriele Marinelli;Davide Barater;Andrea Cavallini;Paolo Seri;
      Pages: 4646 - 4653
      Abstract: The development of more electrical transportation systems requires rotating machines having higher efficiency and specific power. To date, this is achieved by feeding them with rising supply voltages with higher frequencies. This generalized strategy is introducing several challenges in the correct design of the insulation that is necessary for a reliable system. A major issue to be dealt with are partial discharges (PDs), an aging mechanism that can bring insulation to failure in short times. A solution often proposed by manufacturers involves the use of the so-called corona resistant (CR) materials, which supposedly can withstand PD activity. This article investigates the possibility of using CR magnet wires for electrical machines operating at reduced pressures, such as the actuators for primary control surfaces in more electric aircraft. The results show that CR insulations are characterized by an improved behavior at ground level but are not a viable option at reduced pressures.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Review of DC Series Arc Fault Testing Methods and Capability Assessment of
           Test Platforms for More-Electric Aircraft

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      Authors: Vasileios Psaras;Yljon Seferi;Mazheruddin H. Syed;Richard Munro;Patrick J. Norman;Graeme M. Burt;Russell Compton;Kevin Grover;John Collins;
      Pages: 4654 - 4667
      Abstract: In the new era of increasingly electric aircraft, the need for reliable and safe electrical systems is more important than ever. In addition, the wide-scale adoption of dc distribution is considered a key enabling technology for more efficient aircraft operation. In this context, arc fault detection devices (AFDDs) have become a topic of interest for the aviation industry with ongoing research to characterize the impact and adequately protect against severe dc series arc faults. Although dc arc faults have been widely investigated for utility applications (such as solar photovoltaic systems), direct adoption of current practices for validating arc detection devices is not straightforward due to the distinct aircraft operating environment. This article provides a first-of-its-kind landscaping exercise of published series arc fault testing based on factors associated with aircraft applications that have the potential to influence the arc characteristics. In addition, an appraisal and associated gap analysis of published arc test platforms is undertaken in order to assess their suitability to support in-depth testing of the impact and mitigation of series arcs within future aircraft dc electrical systems and identify future testing needs, in particular, to better facilitate a comprehensive performance validation of new AFDDs.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Optical Detection Method for Partial Discharge of Printed Circuit Boards
           in Electrified Aircraft Under Various Pressures and Voltages

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      Authors: Yiming Zang;Mohamad Ghaffarian Niasar;Yong Qian;Xiaoli Zhou;Gehao Sheng;Xiuchen Jiang;Peter Vaessen;
      Pages: 4668 - 4677
      Abstract: Realization of an electrical aircraft demands a low-weight electric distribution and propulsion system. The use of high voltage and power electronics operated at high switching frequencies is essential to achieve this objective. However, printed circuit boards (PCBs) in electrified aircraft are in a harsh working environment, which can make PCBs more susceptible to generate partial discharges (PDs). The current PD detection technology has poor immunity to the electromagnetic interference and acoustic interference in the operating environment of aircraft. Therefore, this article proposes an optical-based PD detection method for PCBs, which is effectively immune to electromagnetic and acoustic interference. This method uses fluorescent fiber as a PD optical signal sensor and then collects the optical signal by the avalanche photodiode (APD). Experiments have verified that the detection sensitivity, sensing range, and anti-interference performance of this method are well satisfied with the PD detection. In addition, single PD pulse, optical phase resolved PD (PRPD) patterns, and PD inception voltage (PDIV) under different air pressure and voltage conditions are investigated. Finally, the relationship between the optical signal and PD amplitude is found to be proportional, which proves that the severity of the PD on PCBs can be effectively detected and evaluated by this method.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Effect of Magnetic Field on Partial Discharge Dynamics in Insulation
           Systems of Transportation Power Devices

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      Authors: Marek Florkowski;
      Pages: 4678 - 4686
      Abstract: The globally observed trend toward electrically supplied devices is common in the transportation segment. Traditionally, the performance of electrical insulation has been assessed with respect to electric stresses and endurance. In all current-carrying devices, magnetic fields will also be superimposed on electric ones; therefore, the influence of a magnetic field’s exposure on partial discharge (PD) dynamics is an actual research topic. This problem is important in the transportation segment as well, where low- and medium-voltage levels are mostly used for supply and energy conversion (which are associated with high load currents). This article is focused on the influence of magnetic fields on the dynamics of PDs in the voids of insulation systems of transportation power devices and refers to both ac and dc cases. A rather weak magnetic field (80 mT) was established in order to detect and analyze early stages of PD behavior. The measurements of PDs that were carried out in a dedicated setup revealed their impact on PD intensity, which have been visualized in time-sequence diagrams and PD images. This detected effect is attributed to both the elongation of the charged particle trajectory and the enhancement of the electron energy due to acceleration. It has been shown that the impact of a magnetic field can be observed within a supply voltage frequency range of 20–400 Hz (which is typical for the transportation segment). The PD intensity was amplified in the above range at a magnetic field induction of 80 mT (even up to 50%). The effect of a magnetic field can be recognized as an additional modulation factor that influences the dynamics of PDs.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Optimal Sensor Placement for Multifault Detection and Isolation in
           Lithium-Ion Battery Pack

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      Authors: Ye Cheng;Matilde D’Arpino;Giorgio Rizzoni;
      Pages: 4687 - 4707
      Abstract: The work presented in this article is motivated by a project related to the electrification of commercial aircraft. Energy storage systems (ESSs) for hybrid-electric aircraft applications require the ability to provide accurate diagnoses to insure system availability and reliability. In aerospace applications, battery packs may consist of thousands of interconnected cells and the associated electrical/electronic hardware, which brings a series of challenges for designing the battery management system (BMS). This article uses the tools of structural analysis to determine the placement of sensors that are needed by the BMS to enable monitoring and fault diagnosis at the individual cell level. First, the degree of analytical redundancy (AR) in the battery system that can be used for diagnostic strategies is determined. Then, structural models of different battery pack architectures are used to study how different measurements (current, voltage, and temperature) may improve the ability to monitor and diagnose a battery system. Possible sensor placement strategies that would enable the diagnosis of individual sensor faults, individual cell faults, and connection faults for different battery pack topologies are analyzed as well. A software-in-the-loop (SIL) framework is utilized to validate the proposed approach.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • A Bayesian Mixture Neural Network for Remaining Useful Life Prediction of
           Lithium-Ion Batteries

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      Authors: Shuxin Zhang;Zhitao Liu;Hongye Su;
      Pages: 4708 - 4721
      Abstract: Remaining useful life (RUL) is one of the essential ingredients in the battery management system. However, due to the characteristic of the dynamic and time-varying electrochemical system with nonlinear and complicated internal mechanisms, the uncertainty of RUL estimation has been expanded, and it is difficult to give an accurate time to reach the end of life. This article proposes the Bayesian mixture neural network (BMNN), a probabilistic deep learning method, to obtain more accurate RUL prediction and provide uncertainty estimation, while the quasi-Gramian angular field (Q-GAF) beneficial to identify prior distribution is utilized to transform time-series sequence into temporal images. BMNN consists of the Bayesian convolutional neural network (BCNN) extracting features in temporal images and Bayesian long short-term memory (B-LSTM) learning correlation between retention capacity and other degradation inducements. After concatenating two terms, the variational Bayesian neural network outputs the distribution of prediction results. In the experimental stage, the performance of the proposed method is validated on four different lithium-ion battery datasets and demonstrates higher stability, lower uncertainty, and more accuracy than other methods.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Early Diagnosis of Accelerated Aging for Lithium-Ion Batteries With an
           Integrated Framework of Aging Mechanisms and Data-Driven Methods

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      Authors: Xinyu Jia;Caiping Zhang;Le Yi Wang;Linjing Zhang;Xingzhen Zhou;
      Pages: 4722 - 4742
      Abstract: Accelerated aging is a significant issue for various lithium-ion battery applications, such as electric vehicles, energy storage, and electronic devices. Effective early diagnosis is prominent to restrict battery failure. Typical battery classification data-driven methods are structured to capture features from data without considering the underlying aging mechanism. On the other hand, analysis of the detailed aging mechanism that can generate electrochemistry-based models can be highly complicated and may not be suitable for real-time battery management. In this article, the accelerated aging diagnosis method is systematically investigated. The accelerated aging mechanisms of the Li[NiCoMn]O2 (NCM) battery are analyzed by the nondestructive quantitative diagnostic method. We prove the feasibility of accelerated aging diagnosis based on the accelerated aging mechanism analysis. An integrated framework of aging mechanisms and data-driven methods (IFAMDM) is introduced for lithium-ion battery-accelerated aging diagnosis. Highly adaptable features reflecting the accelerated aging mechanism are proposed for lithium-ion battery-accelerated aging. Then, we propose a combination method to diagnose battery-accelerated aging. The IFAMDM was verified on two types of battery datasets. The IFAMDM is proved to be highly generic and accurate for lithium-ion battery-accelerated aging diagnosis at the 100th cycle.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Design and Validation of a 20-kVA, Fully Cryogenic, Two-Level GaN-Based
           Current Source Inverter for Full Electric Aircrafts

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      Authors: Mustafeez ul Hassan;Asif Imran Emon;Fang Luo;Vyacheslav Solovyov;
      Pages: 4743 - 4759
      Abstract: This article presents the design of a cryogenic power electronics converter using wide bandgap (WBG) devices. A 20-kVA two-level current source inverter (2L-CSI) is designed and validated under both room temperature (RT) and cryogenic temperature (CT) of 77 K. CSI has been neglected because of the physically large and heavy dc-link inductor compared to the dc-link capacitor of voltage source inverters (VSIs). However, higher power, together with operation at CT in fully electric aircrafts (FEAs), makes them superior in size, volume, and power quality. The advantage in volume is primarily attributed to the utilization of air-core inductors with superconducting tapes as dc-link storage elements. Therefore, a 2L-CSI with both power stage and associated components at CT is designed and evaluated. As part of converter development, commercially off-the-shelf (COTS) products, including integrated circuits (ICs), isolated auxiliary power supplies, and passive components, were utilized. Numerous laboratory prototypes of cryogenic subsystems were built to screen out the cryocompatible components. Based on components screening, converter subsystems, namely, the gate driver (GD) board and the double-pulse test (DPT) platform, were also developed. Characterization of these subsystems was performed both at RT and CT, where both individual testing and integrated testing were carried out.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Dual Use of Liquid Hydrogen in a Next-Generation PEMFC-Powered Regional
           Aircraft With Superconducting Propulsion

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      Authors: Christian Hartmann;Jonas Kristiansen Nøland;Robert Nilssen;Runar Mellerud;
      Pages: 4760 - 4778
      Abstract: In this article, we present a comprehensive model framework for a disruptive cryoelectric propulsion system intended for a hydrogen-powered regional aircraft. The main innovation lies in the systematic treatment of all the electrical and thermal components to model the overall system performance. One of the main objectives is to study the feasibility of using the liquid hydrogen (LH2) fuel to provide cryogenic cooling to the cryoelectric propulsion system and, thereby, enable ultracompact designs. Another aim has been to identify the optimal working point of the fuel cell to minimize the overall propulsion system’s mass. The full mission profile is evaluated to make the analysis as realistic as possible. Analyses are done for three different 2035 scenarios, where available data from the literature are projected to a baseline, conservative, and optimistic scenario. The results show that the total propulsion system’s power density can be as high as 1.63 kW/kg in the optimistic scenario and 0.79 kW/kg in the baseline scenario. In the optimistic scenario, there is also sufficient cryogenic cooling capacity in the hydrogen to secure proper conditions for all components, whereas the dc/dc converter falls outside the defined limit of 110 K in the baseline scenario.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • A Power-Electronics Free Protection Device for Superconducting Electrical
           Propulsion Aircraft

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      Authors: Hongxu Li;Bin Xiang;Shuting Yu;Ting Yu;Yingsan Geng;Zhiyuan Liu;Jianhua Wang;
      Pages: 4779 - 4788
      Abstract: Research into developing cryogenic protection devices for superconducting electrical systems is lacking. One of the few investigations was of cryogenic switches in the form of a solid-state circuit breaker (CB). It was reported that these breakers would take up nearly 40% of the superconducting electrical system mass and losses. This article designs a cryogenic switch, free of power electronics, whose conduction loss is only 4.1% of a comparable solid-state CB’s total loss. Protection considerations of a 1-kV/40-MW cryogenic system are referred to validate its application in a superconducting electrical powertrain. The designed cryogenic switch’s dc and ac interrupting ability were verified by experiments to interrupt 750-V/1500-A dc and 1-kV/6.3-kA ac, very close to the dc and ac limits of the proposed 40-MW Center for High Efficiency Electric Aircraft (CHEETA) system. For fault conditions, a noninductive pancake resistive superconducting fault current limiter unit was designed to help with the unacceptable fault current. The 750-V/10-kA prospective current was suppressed to 1.4 kA in 588 $mu text{s}$ and interrupted by the switch in 12 ms. Cooperation of the cryogenic switch and superconducting fault current limiter shows potential in dealing with fault currents in future electric aircraft.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Sizing of Superconducting Cables for Turbo-ElectricDistributed Propulsion
           Aircraft Using a Particle Swarm Optimization Approach

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      Authors: Steven Nolan;Catherine E. Jones;Patrick J. Norman;Graeme M. Burt;
      Pages: 4789 - 4798
      Abstract: Superconducting electrical power systems are proposed to meet high specific power densities required for turbo-electric distributed propulsion aircraft. Superconducting materials have unique thermal and electrical requirements for maintaining the superconducting state, which is critical to their normal operation. Electrical system faults can lead to this state being lost for all network assets in the electrical fault path. The resulting temperature rise can prevent the superconducting state from being immediately resumed following fault clearance, requiring disconnection of nonfaulted equipment. Undersized cables experience a higher temperature rise under faulted conditions and disconnect from the system more readily. Oversized cables are heavier and more costly. Therefore, there is a need to optimize the cable size, preventing disconnection of equipment due to temperature rise following a fault while minimizing the weight and cost penalty. This article proposes a system parameter-driven methodology, using particle swarm optimization, to identify fault-tolerant cable designs, which deliver minimum through-life costs. This facilitates high-value, quantifiable design trade studies incorporating system parameters. Key observations drawn are that the choice between improving fault ride-through capability of a superconducting cable by increasing the amount of either superconducting material or conventional former material strongly depends on acceptable system operating temperature and voltage.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • Information for Authors

    • Free pre-print version: Loading...

      Pages: 4799 - 4801
      Abstract: These instructions give guidelines for preparing papers for this publication. Presents information for authors publishing in this journal.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
  • 2022 Index IEEE Transactions on Transportation Electrification Vol. 8

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      Pages: 4802 - 4871
      Abstract: Presents the 2022 author/subject index for this issue of the publication.
      PubDate: Dec. 2022
      Issue No: Vol. 8, No. 4 (2022)
       
 
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