中文摘要：

测试传导性干扰的模态噪声，是设计电磁干扰（EMI）滤波器的前提条件。共模扼流圈能够抑制共模模态，而不影响差模电流的输出。根据共模扼流圈这一特点，设计一种由两个共模扼流圈为核心的共模/差模分离网络，实现共模电压和差模电压的同时输出。仿真结果表明，在150 kHz~30 MHz的测试频带，输入端口阻抗基本在50Ω，并且共模传递比（CMTR）、差模抑制比（DMRR）、差模传递比（DMTR）及共模抑制比（CMRR）四个结果显示了该分离网络的良好模态分离效果。

英文摘要：

Testing for conducted electromagnetic interference is a precondition for design of EMI filters. The common mode choke can reject the common mode（CM）modal,but does nothing with the output of differential mode（DM）current. According to this characteristic of CM choke,a novel separation network for CM and DM EMI was designed to carry out the voltage output of both CM and DM,which consists of two common mode chokes. The simulation results indicates that the input impedances holds on 50 Ω at the frequency range of 150 kHz~30 MHz. The four results of CM transmission ratio（CMTR）,DM rejection ra-tio （DMRR）,DM transmission ratio （DMTR） and CM rejection ratio （CMRR） revealed the perfect mode separation perfor-mance of this separation network.