基于插入无源二端口网络的噪声源阻抗提取方法研究  

Research on Noise Soure Impedance Extraction Method Based on Inserting Passive Two-Port Network

作　　者：彭金融 毛行奎[1,2] 崔文玲 董纪清 张艺明[1,2] Peng Jinrong;Mao Xingkui;Cui Wenling;Dong Jiqing;Zhang Yiming(College of Electrical Engineering and Automation Fuzhou University,Fuzhou 350108 China;Fujian Key Laboratory of New Energy Generation and Power Conversion,Fuzhou 350108 China)

机构地区：[1]福州大学电气工程与自动化学院,福州350108 [2]福建省新能源发电与功率变换重点实验室,福州350108

出　　处：《电工技术学报》2023年第2期523-532,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(51207025,52107183)。

摘　　要：为了使电磁干扰(EMI)滤波器设计达到预期的插入损耗(IL),实现良好噪声抑制效果,需要考虑噪声源阻抗的影响。电压插入损耗法仅能获得噪声源阻抗幅值的范围,且无法求解相位。针对上述问题,在不增加实验设备的前提下,提出基于插入无源二端口网络的噪声源阻抗提取方法。该方法通过在被测设备(EUT)与线性阻抗稳定网络(LISN)之间插入3个不同的无源二端口网络,建立关于噪声源阻抗实部和虚部的二元二次方程组,再结合EMI测试频段范围内实验测量的有效频点噪声电流,以实现噪声源阻抗幅值和相位的精确计算。以一台工业照明LED驱动电源为测试对象,对该方法的有效性和适用性进行了验证。实验结果表明,相较于电压插入损耗法,所提方法能够准确地提取全频段(9kHz~30MHz)噪声源阻抗幅值的精确值,并且能够得到噪声源阻抗相位,从而可以预测EMI噪声电流,为设计性能优良的EMI滤波器提供精确理论基础。Insertion loss(IL)of EMI filter is closely related to noise source impedance and load impedance.Therefore,in order to make the EMI filter design achieve the expected IL and achieve good noise suppression effect,it is necessary to consider the impact of noise source impedance.The voltage insertion loss method can only calculate the maximum and minimum values of the amplitude of the noise source impedance,and cannot solve the phase of the noise source impedance.To solve the above problems,this paper proposes a noise source impedance extraction method based on inserting passive two-port network without adding experimental equipment.Combined with experimental measurement and theoretical calculation,the accurate values of the amplitude and phase of the noise source impedance are obtained.First,insert three different passive two-port networks between the equipment under test(EUT)and the linear impedance stabilization network(LISN).Secondly,the equivalent circuit of noise source impedance extraction is established,and then the binary quadratic equations about the real part and imaginary part of the noise source impedance are established according to the equivalent circuit.Finally,through the programming of the mathematical software platform,the binary quadratic equations corresponding to each frequency point are solved automatically and circularly,and the effective frequency points measured experimentally in the conducted EMI test frequency band(9kHz~30MHz)are selected,so that the real and imaginary parts of the noise source impedance can be obtained,and then the accurate calculation of the amplitude and phase of the noise source impedance can be realized.The experimental results show that,no matter the common mode(CM)noise source impedance or the differential mode(DM)noise source impedance,most of the amplitudes of the noise source impedance calculated by the proposed method fall between the maximum and minimum values of the amplitudes of the noise source impedance calculated by the voltage insertion loss method in the

关 键 词：电磁干扰 噪声源阻抗 插入损耗 EMI滤波器 

分 类 号：TN713[电子电信—电路与系统]