差共模噪声相互转化机理及在平面EMI滤波器设计中的应用  

Theoretical Investigation of Mutual Transformation between Differential Mode and Common Mode Noise and Its Implementation in the Design of Planar EMI Filter

作　　者：王世山[1] 龚敏[1] 虞振洋 

机构地区：[1]江苏省新能源发电与电能变换重点实验室(南京航空航天大学),南京210016

出　　处：《电工技术学报》2014年第2期239-246,共8页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51177071);台达环境与教育基金会<电力电子科教发展计划>(DREK2013004);江苏省高校优秀科技创新团队项目资助

摘　　要：EMI滤波器是抑制传导干扰的重要元件。论文对差、共模混合噪声电路在"阻抗失配"的基础上,可以分离为两部分独立的等效通道。对两个通道各自加载差模和共模噪声,求解电路网络,在负载端可以得到差、共模干扰噪声。由此,可以得到由于支路阻抗的不对称而引起的差、共模噪声之间的相互转化。基于环形结构的平面EMI滤波器是本课题组提出的一种新型结构,但是仍然存在对应支路阻抗不对称问题引起噪声相互转化的问题。为此,本文提出一种单面完全覆金属的"感容"集成模块(LC单元),与双面均为螺旋型LC单元进行比较表明,所提出的模块具有良好对称性,能更好地抑制平面滤波器差、共模噪声之间的相互转化。EMI filter is an important component to suppress the conducted EMI noise. Based on“impedance mismatch”, the DM and CM circuit can be separated into two independent equivalent channels. Applying DM and CM noise for each channel, the DM and CM interference noise can be achieved in the load by solving the circuit network. Thus, the transformation between the DM and CM noise can be obtained, which caused by the asymmetric branch impedance. The important conclusions are achieved, that is, inhibiting the “CM noise from the DM excitations” is more difficult. Annular planar EMI filter is a new structure proposed by our research group, but there are still existing the transformation problems, which caused by the asymmetric branch impedance. Therefore, in this paper, a new kind of“LC” integrated module with one side fully covered with metal（LC unit） is proposed. Meantime, it is compared with the LC unit which has spiral on both sides. Research shows that, the proposed model has a good symmetry and can effectively reduce the transformation between the DM and CM noise.

关 键 词：平面EMI滤波器 差模噪声 共模噪声 噪声转化 有限元 differential noise(DM) common noise(CM) FINITE element method(FEM) 

分 类 号：TM133[电气工程—电工理论与新技术] TM713