Wireless power transfer(WPT) to support mobile and portable devices is an emerging wireless technique.Among all kinds of approaches,magnetic resonance coupling(MRC) is an excellent one for mid-range WPT,which provides...Wireless power transfer(WPT) to support mobile and portable devices is an emerging wireless technique.Among all kinds of approaches,magnetic resonance coupling(MRC) is an excellent one for mid-range WPT,which provides better mobility,flexibility,and convenience due to its simplicity in hardware implementation and longer transmission distances.In this paper,we consider an MRCWPT system with multiple power transmitters,one intended power receiver and multiple unintended power receivers.We investigate the probabilistic robust beamforming designs and provide efficient algorithms to achieve the local optimums under two different criteria,i.e.,total source power minimization problem and min-max unintended receiving power restriction problem.As the problems are quite typical in robust design situations,our proposed robust beamformers can be conveniently applied to other probabilistic robust design problems,thus reduce the complexity as well as improve the beamforming performance.Numerical results demonstrate that the proposed algorithms can significantly improve the performance as well as the robustness of the WPT system.展开更多
Magnetic radiation phenomena appear inevitably in the magnetic-resonance wireless power transfer （MR-WPT） system, and regarding this problem the magnetic-shielding scheme is applied to improve the electromagnetic pe...Magnetic radiation phenomena appear inevitably in the magnetic-resonance wireless power transfer （MR-WPT） system, and regarding this problem the magnetic-shielding scheme is applied to improve the electromagnetic performance in engineering. In this study, the shielding effectiveness of a two-coil MR-WPT system for different material shields is analyzed in theory using Moser＇s formula and Schelkunoff＇s formula. On this basis a candidate magnetic-shielding scheme with a double-layer structure is determined, which has better shielding effectiveness and coils coupling coefficient. Finally, some finite element simulation results validate the correctness of the theoretical analysis, and the shielding effectiveness with the double-layer shield in maximum is 30？dB larger than the one with the single-layer case.展开更多
将无线电能传输技术引入航天器的旋转供电中是推动航天器进一步发展的重要手段。而现有应用最广的磁耦合式无线电能传输技术(inductive power transfer,IPT)因成本高、重量大、存在涡流损耗等缺陷而难以在航天领域中得到大规模应用。而...将无线电能传输技术引入航天器的旋转供电中是推动航天器进一步发展的重要手段。而现有应用最广的磁耦合式无线电能传输技术(inductive power transfer,IPT)因成本高、重量大、存在涡流损耗等缺陷而难以在航天领域中得到大规模应用。而电场耦合式无线电能传输技术(capacitive power transfer,CPT)以其成本低、重量轻等优点,近年来受到广泛关注,在航天领域具有巨大潜力。从传统IPT技术在航天领域应用的缺陷入手,分析将CPT技术引入航天领域无线供电场景的重要性。进而介绍了CPT技术的发展历程与基本原理,并对CPT技术在轻量化、大功率、旋转型三个领域的研究现状进行综述来论证其在航天领域应用的潜力。最后总结了CPT技术在航天领域应用存在的问题并分析了解决这些问题可行的技术手段。展开更多
针对煤矿井下复杂环境,为了提高其WPT(Wireless Power Transmission无线电能传输)功率并降低发射端线圈电压,改进了井下WPT发射端的线圈结构,并提出了适合井下WPT的传输模型。根据电路互感耦合理论,推导出WPT系统传输功率与传输效率的...针对煤矿井下复杂环境,为了提高其WPT(Wireless Power Transmission无线电能传输)功率并降低发射端线圈电压,改进了井下WPT发射端的线圈结构,并提出了适合井下WPT的传输模型。根据电路互感耦合理论,推导出WPT系统传输功率与传输效率的数学表达式,分别阐述了耦合系数、输入频率、负载大小对传输功率与传输效率的影响。设计过程中应用Or CAD与Matlab软件对传输系统各个影响因素进行仿真分析,在此基础上设计并制作了实验平台。实验分析得出此传输系统存在最佳功率传输距离和最佳效率传输距离,总体实验结果与理论仿真结果一致,最后通过与典型WPT系统做对比实验分析,得出改进WPT系统提高了传输功率,可为实际井下WPT提供理论参考。展开更多
基金supported by National Natural Science Foundation of China(Grant No.61771185,61831013)Science and Technology Research Project of Henan Province(Grant No.182102210044)+1 种基金Key Scientific Research Program of Henan Higher Education(Grant No.18A510009)Beijing Municipal Natural Science Foundation(Grant No.4182030)
文摘Wireless power transfer(WPT) to support mobile and portable devices is an emerging wireless technique.Among all kinds of approaches,magnetic resonance coupling(MRC) is an excellent one for mid-range WPT,which provides better mobility,flexibility,and convenience due to its simplicity in hardware implementation and longer transmission distances.In this paper,we consider an MRCWPT system with multiple power transmitters,one intended power receiver and multiple unintended power receivers.We investigate the probabilistic robust beamforming designs and provide efficient algorithms to achieve the local optimums under two different criteria,i.e.,total source power minimization problem and min-max unintended receiving power restriction problem.As the problems are quite typical in robust design situations,our proposed robust beamformers can be conveniently applied to other probabilistic robust design problems,thus reduce the complexity as well as improve the beamforming performance.Numerical results demonstrate that the proposed algorithms can significantly improve the performance as well as the robustness of the WPT system.
基金Supported by the National Natural Science Foundation of China under Grant No 51377185
文摘Magnetic radiation phenomena appear inevitably in the magnetic-resonance wireless power transfer （MR-WPT） system, and regarding this problem the magnetic-shielding scheme is applied to improve the electromagnetic performance in engineering. In this study, the shielding effectiveness of a two-coil MR-WPT system for different material shields is analyzed in theory using Moser＇s formula and Schelkunoff＇s formula. On this basis a candidate magnetic-shielding scheme with a double-layer structure is determined, which has better shielding effectiveness and coils coupling coefficient. Finally, some finite element simulation results validate the correctness of the theoretical analysis, and the shielding effectiveness with the double-layer shield in maximum is 30？dB larger than the one with the single-layer case.
文摘将无线电能传输技术引入航天器的旋转供电中是推动航天器进一步发展的重要手段。而现有应用最广的磁耦合式无线电能传输技术(inductive power transfer,IPT)因成本高、重量大、存在涡流损耗等缺陷而难以在航天领域中得到大规模应用。而电场耦合式无线电能传输技术(capacitive power transfer,CPT)以其成本低、重量轻等优点,近年来受到广泛关注,在航天领域具有巨大潜力。从传统IPT技术在航天领域应用的缺陷入手,分析将CPT技术引入航天领域无线供电场景的重要性。进而介绍了CPT技术的发展历程与基本原理,并对CPT技术在轻量化、大功率、旋转型三个领域的研究现状进行综述来论证其在航天领域应用的潜力。最后总结了CPT技术在航天领域应用存在的问题并分析了解决这些问题可行的技术手段。
文摘针对煤矿井下复杂环境,为了提高其WPT(Wireless Power Transmission无线电能传输)功率并降低发射端线圈电压,改进了井下WPT发射端的线圈结构,并提出了适合井下WPT的传输模型。根据电路互感耦合理论,推导出WPT系统传输功率与传输效率的数学表达式,分别阐述了耦合系数、输入频率、负载大小对传输功率与传输效率的影响。设计过程中应用Or CAD与Matlab软件对传输系统各个影响因素进行仿真分析,在此基础上设计并制作了实验平台。实验分析得出此传输系统存在最佳功率传输距离和最佳效率传输距离,总体实验结果与理论仿真结果一致,最后通过与典型WPT系统做对比实验分析,得出改进WPT系统提高了传输功率,可为实际井下WPT提供理论参考。
