This paper presents a new approach for modeling of the conducted electromagnetic interference(EMI) prediction for widely used converter systems.Coupling paths and mechanism of differential mode(DM) interference and co...This paper presents a new approach for modeling of the conducted electromagnetic interference(EMI) prediction for widely used converter systems.Coupling paths and mechanism of differential mode(DM) interference and common mode(CM) interference have been analyzed.Models to predict the high-frequency noise of PWM converter system are created.A direct calculation method in frequency domain is proposed for the deduction of frequency spectrum.A method is given for obtaining the parasitic parameters and topological structure of the model.An experimental investigation of the conducted emission from an actual high-power rectifier system is described.The validity of the models is confirmed by comparison to laboratory measurements.展开更多
A compact input-reflectionless balanced bandpass filter(BPF)with flexible bandwidth(BW)using a three-line coupled structure(TLCS)is presented in this paper.For the differential mode(DM),the TLCS is applied to achieve ...A compact input-reflectionless balanced bandpass filter(BPF)with flexible bandwidth(BW)using a three-line coupled structure(TLCS)is presented in this paper.For the differential mode(DM),the TLCS is applied to achieve the bandpass response;meanwhile,the input coupled-feed line of the TLCS is reused in the input absorption network.This design shows a good fusion of the absorptive and BPF sections,effectively reducing the circuit size,and the BWs of the two sections that can be controlled separately result in a flexibly controllable DM response BW of the proposed input-reflectionless balanced BPF.Detailed analyses of the ratio of the two-part BWs have been given for the first time,which is vital for the passband flatness and reflectionless feature.In the codesign of this work,the input-reflectionless DM bandpass response can be optimized easily,while wideband common mode(CM)noise absorption is achieved by the input absorption network.To verify the design method,a prototype with a compact layout(0.52λ×0.36λ)is designed and measured in the 0-7.0 GHz range.The DM center frequency(f0)is 2.45 GHz with a measured 3 dB fractional bandwidth of 31.4%.The simulation and measurement results with good agreement are presented,showing good performance,e.g.,low insertion loss(0.43 dB),wide upper stopband for the DM bandpass response(over 20 dB rejection level up to 2.72f0),and wideband DM reflectionless and CM noise absorption(fractional absorption bandwidth of 285.7%).展开更多
针对Hubing电流驱动模型中认为电流在辐射线缆中是均一分布的,幅值和相位保持不变即未考虑辐射线缆共模电流频率效应给辐射电磁干扰噪声预估带来的误差的问题.文中利用电流传输波动特性建立了辐射线缆长度与共模电流波长为同一数量级时...针对Hubing电流驱动模型中认为电流在辐射线缆中是均一分布的,幅值和相位保持不变即未考虑辐射线缆共模电流频率效应给辐射电磁干扰噪声预估带来的误差的问题.文中利用电流传输波动特性建立了辐射线缆长度与共模电流波长为同一数量级时的辐射线缆共模电流分布模型,并设计电路模型进行测试预估.实验结果表明:采用文中方法预估辐射电磁干扰噪声与Hubing电流驱动模型预估方法相比能提高20.12dB_μV/m,更加接近标准暗室测试结果,从而为辐射电磁干扰(Electro Magnetic Interference,EMI)测试与分析提供理论依据.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 50977063)Key Science and Technology Supporting Project of Tianjin (Grant No. 09ZCKFGX01800)
文摘This paper presents a new approach for modeling of the conducted electromagnetic interference(EMI) prediction for widely used converter systems.Coupling paths and mechanism of differential mode(DM) interference and common mode(CM) interference have been analyzed.Models to predict the high-frequency noise of PWM converter system are created.A direct calculation method in frequency domain is proposed for the deduction of frequency spectrum.A method is given for obtaining the parasitic parameters and topological structure of the model.An experimental investigation of the conducted emission from an actual high-power rectifier system is described.The validity of the models is confirmed by comparison to laboratory measurements.
基金Project supported by the National Natural Science Foundation of China(No.20201438)。
文摘A compact input-reflectionless balanced bandpass filter(BPF)with flexible bandwidth(BW)using a three-line coupled structure(TLCS)is presented in this paper.For the differential mode(DM),the TLCS is applied to achieve the bandpass response;meanwhile,the input coupled-feed line of the TLCS is reused in the input absorption network.This design shows a good fusion of the absorptive and BPF sections,effectively reducing the circuit size,and the BWs of the two sections that can be controlled separately result in a flexibly controllable DM response BW of the proposed input-reflectionless balanced BPF.Detailed analyses of the ratio of the two-part BWs have been given for the first time,which is vital for the passband flatness and reflectionless feature.In the codesign of this work,the input-reflectionless DM bandpass response can be optimized easily,while wideband common mode(CM)noise absorption is achieved by the input absorption network.To verify the design method,a prototype with a compact layout(0.52λ×0.36λ)is designed and measured in the 0-7.0 GHz range.The DM center frequency(f0)is 2.45 GHz with a measured 3 dB fractional bandwidth of 31.4%.The simulation and measurement results with good agreement are presented,showing good performance,e.g.,low insertion loss(0.43 dB),wide upper stopband for the DM bandpass response(over 20 dB rejection level up to 2.72f0),and wideband DM reflectionless and CM noise absorption(fractional absorption bandwidth of 285.7%).
文摘针对Hubing电流驱动模型中认为电流在辐射线缆中是均一分布的,幅值和相位保持不变即未考虑辐射线缆共模电流频率效应给辐射电磁干扰噪声预估带来的误差的问题.文中利用电流传输波动特性建立了辐射线缆长度与共模电流波长为同一数量级时的辐射线缆共模电流分布模型,并设计电路模型进行测试预估.实验结果表明:采用文中方法预估辐射电磁干扰噪声与Hubing电流驱动模型预估方法相比能提高20.12dB_μV/m,更加接近标准暗室测试结果,从而为辐射电磁干扰(Electro Magnetic Interference,EMI)测试与分析提供理论依据.
