针对复杂电子系统产生的传导EMI噪声,该文分别利用电偶极子模型、电路分析方法和散射参数方法提出了3种传导EMI噪声理论模型及其等效电路,包括因串扰引起的传导噪声模型,因接地不良引起的传导噪声模型,以及因PCB线缆阻抗失配引起的传导...针对复杂电子系统产生的传导EMI噪声,该文分别利用电偶极子模型、电路分析方法和散射参数方法提出了3种传导EMI噪声理论模型及其等效电路,包括因串扰引起的传导噪声模型,因接地不良引起的传导噪声模型,以及因PCB线缆阻抗失配引起的传导噪声模型。同时,还设计了一种串扰扼流圈以有效抑制因串扰引起的传导EMI噪声。实验结果表明,采用文中方法,某型商用车载导航和刷卡器能够通过GB 9254标准测试,噪声抑制效果分别可达44.8和29.28 dB V,从而验证了方法的有效性。展开更多
Solid-state transformers(SSTs)have been widely used in many areas owing to their advantages of high-frequency isolation and high power density.However,high-frequency switching causes severe electromagnetic interferenc...Solid-state transformers(SSTs)have been widely used in many areas owing to their advantages of high-frequency isolation and high power density.However,high-frequency switching causes severe electromagnetic interference(EMI)problems.Particularly,the common-mode(CM)EMI caused by the switching of the dual active bridge(DAB)converter is conducted through the parasitic capacitances in the high-frequency transformer and impacts the system reliability.With the understanding of the CM EMI model in SSTs,CM EMI mitigation methods have been studied.For passive mitigation,the coupled inductor can be integrated with the phase-shift inductor function to reduce CM EMI.For active mitigation,variations in the DAB switching frequency can help reduce the CM EMI peak.An active EMI filter can also be designed to sample and compensate for CM EMI.Using these methods,CM EMI can be reduced in SSTs.展开更多
研究了电力线噪声分离网络技术,包括网络拓扑优化、分离网络元器件性能改善以及利用散射参数测量进行分离网络参数提取等。结果表明,上述技术可明显提高分离网络性能,如插损提高约3dB,噪声抑制比提高15dB以上。此外还分别完成了基于噪...研究了电力线噪声分离网络技术,包括网络拓扑优化、分离网络元器件性能改善以及利用散射参数测量进行分离网络参数提取等。结果表明,上述技术可明显提高分离网络性能,如插损提高约3dB,噪声抑制比提高15dB以上。此外还分别完成了基于噪声分离网络的开关电源电力线传导噪声和电力载波通信(power line communication,PLC)中的电力线辐射干扰噪声诊断抑制2个实验,验证了文中方法有效性。展开更多
Electromagnetic interference (EMI) causes electromechanical damage to the motors and degrades the reliability of variable-frequency drive (VFD) systems. Unlike fundamental frequency components in motor drive syste...Electromagnetic interference (EMI) causes electromechanical damage to the motors and degrades the reliability of variable-frequency drive (VFD) systems. Unlike fundamental frequency components in motor drive systems, high-frequency EMI noise, coupled with the parasitic parameters of the trough system, are difficult to analyze and reduce. In this article, EMI modeling techniques for different function units in a VFD system, including induction motors, motor bearings, and rectifierinverters, are reviewed and evaluated in terms of applied frequency range, model parameterization, and model accuracy. The EMI models for the motors are categorized based on modeling techniques and model topologies. Motor bearing and shaft models are also reviewed, and techniques that are used to eliminate bearing current are evaluated. Modeling techniques for conventional rectifierinverter systems are also summarized. EMI noise suppres- sion techniques, including passive filter, Wheatstone bridge balance, active filter, and optimized modulation, are reviewed and compared based on the VFD system models.展开更多
With the increase in the switching frequency and power density,DC-DC converters encounter more severe electromagnetic interference(EMI)problems.To suppress the common-mode EMI generated by converters,as well as mainta...With the increase in the switching frequency and power density,DC-DC converters encounter more severe electromagnetic interference(EMI)problems.To suppress the common-mode EMI generated by converters,as well as maintain the high-power-density of converters,the active EMI filter(AEF)has attracted increasing interest owing to its small volume.The EMI suppression effect of the common single-stage single-sense single-injection AEF is confined because of the limited insertion loss,and the volume of the multi-stage AEF will be bulky.To solve this problem,this paper proposes a compact dual-current-injection current-sense current-compensation(DCJ-CSCC)AEF to increase the insertion loss in the entire conducted EMI frequency band,as well as considering the volume of the AEF.The structure and operating principle of the proposed AEF are introduced.Finally,taking a boost converter as an example,the effectiveness and advantages of the proposed DCJ-CSCC AEF were verified through a simulation and experiment,the results show that the proposed AEF has a better EMI suppression effect on the entire conducted EMI frequency band with a similar volume compared with existing single-injection feedforward current-sense current-compensation(FF-CSCC)and feedback current-sense current-compensation(FB-CSCC)AEFs.This paper provides a new selection for EMI suppression in DC-DC converters.展开更多
文摘针对复杂电子系统产生的传导EMI噪声,该文分别利用电偶极子模型、电路分析方法和散射参数方法提出了3种传导EMI噪声理论模型及其等效电路,包括因串扰引起的传导噪声模型,因接地不良引起的传导噪声模型,以及因PCB线缆阻抗失配引起的传导噪声模型。同时,还设计了一种串扰扼流圈以有效抑制因串扰引起的传导EMI噪声。实验结果表明,采用文中方法,某型商用车载导航和刷卡器能够通过GB 9254标准测试,噪声抑制效果分别可达44.8和29.28 dB V,从而验证了方法的有效性。
文摘Solid-state transformers(SSTs)have been widely used in many areas owing to their advantages of high-frequency isolation and high power density.However,high-frequency switching causes severe electromagnetic interference(EMI)problems.Particularly,the common-mode(CM)EMI caused by the switching of the dual active bridge(DAB)converter is conducted through the parasitic capacitances in the high-frequency transformer and impacts the system reliability.With the understanding of the CM EMI model in SSTs,CM EMI mitigation methods have been studied.For passive mitigation,the coupled inductor can be integrated with the phase-shift inductor function to reduce CM EMI.For active mitigation,variations in the DAB switching frequency can help reduce the CM EMI peak.An active EMI filter can also be designed to sample and compensate for CM EMI.Using these methods,CM EMI can be reduced in SSTs.
文摘研究了电力线噪声分离网络技术,包括网络拓扑优化、分离网络元器件性能改善以及利用散射参数测量进行分离网络参数提取等。结果表明,上述技术可明显提高分离网络性能,如插损提高约3dB,噪声抑制比提高15dB以上。此外还分别完成了基于噪声分离网络的开关电源电力线传导噪声和电力载波通信(power line communication,PLC)中的电力线辐射干扰噪声诊断抑制2个实验,验证了文中方法有效性。
文摘Electromagnetic interference (EMI) causes electromechanical damage to the motors and degrades the reliability of variable-frequency drive (VFD) systems. Unlike fundamental frequency components in motor drive systems, high-frequency EMI noise, coupled with the parasitic parameters of the trough system, are difficult to analyze and reduce. In this article, EMI modeling techniques for different function units in a VFD system, including induction motors, motor bearings, and rectifierinverters, are reviewed and evaluated in terms of applied frequency range, model parameterization, and model accuracy. The EMI models for the motors are categorized based on modeling techniques and model topologies. Motor bearing and shaft models are also reviewed, and techniques that are used to eliminate bearing current are evaluated. Modeling techniques for conventional rectifierinverter systems are also summarized. EMI noise suppres- sion techniques, including passive filter, Wheatstone bridge balance, active filter, and optimized modulation, are reviewed and compared based on the VFD system models.
基金Supported in part by the Royal Academy of Engineering:Transforming Systems through Partnership(China)under Grant TSPC1017in part by the Excellent Youth Scholars of National Natural Science Foundation of China under Grant 51822701in part by the Key Project of National Natural Science Foundation of China and Smart Grid Joint Fund of State Grid Corporation of China under Grant U1866211.
文摘With the increase in the switching frequency and power density,DC-DC converters encounter more severe electromagnetic interference(EMI)problems.To suppress the common-mode EMI generated by converters,as well as maintain the high-power-density of converters,the active EMI filter(AEF)has attracted increasing interest owing to its small volume.The EMI suppression effect of the common single-stage single-sense single-injection AEF is confined because of the limited insertion loss,and the volume of the multi-stage AEF will be bulky.To solve this problem,this paper proposes a compact dual-current-injection current-sense current-compensation(DCJ-CSCC)AEF to increase the insertion loss in the entire conducted EMI frequency band,as well as considering the volume of the AEF.The structure and operating principle of the proposed AEF are introduced.Finally,taking a boost converter as an example,the effectiveness and advantages of the proposed DCJ-CSCC AEF were verified through a simulation and experiment,the results show that the proposed AEF has a better EMI suppression effect on the entire conducted EMI frequency band with a similar volume compared with existing single-injection feedforward current-sense current-compensation(FF-CSCC)and feedback current-sense current-compensation(FB-CSCC)AEFs.This paper provides a new selection for EMI suppression in DC-DC converters.