单管正激变换器传导共模EMI特性分析  

Analysis of Conducted Common-mode EMI Characteristics of Single-switch Forward Converter

作　　者：彭长川 陈为[1] 林苏斌[1] PENG Changchuan;CHEN Wei;LIN Subin(College of Electrical Engineering and Automation,Fuzhou University,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

出　　处：《电源学报》2025年第2期298-306,共9页Journal of Power Supply

基　　金：国家自然科学基金资助项目(51777036);福建省自然科学基金资助项目(2022J01565)。

摘　　要：为了研究单管正激变换器传导共模EMI特性,降低单管正激变换器的共模噪声,对单管正激变换器的传导共模噪声传输机理进行分析。基于分析建立共模噪声路径模型,提出1种计算方法明确外接电容大小来改善共模噪声;同时针对传统计算二次侧感应电荷量模型存在的缺陷,提出改进计算模型,通过仿真验证表明理想条件下改进模型准确性较高;然后使用平衡绕组的方法降低流经变压器的共模噪声,并通过1台单管正激电源样机进行实验验证,结果表明了计算外接电容方法的有效性,及在绕组距离较近且绕组较密情况下,改进计算模型计算的电荷量准确性较高。To study the conducted common-mode(CM)electromagnetic interference(EMI)characteristics of a single-switch forward converter and reduce its CM noise,the analysis of the transmission mechanism of conducted CM noise in the single-switch forward converter is necessary.On this basis,a CM noise transmission path model is established,and a calculation method is proposed to determine the specific external capacitance to reduce the CM noise.In addition,aimed at the defects of the traditional calculation model of induced charge on the secondary side,an improved calculation model is put forward,and simulation results show that the accuracy of the improved model is higher under ideal conditions.Afterwards,the balanced winding method was used to reduce the CM noise flowing through the transformer,and a prototype of single-switch forward converter power supply was used for experimental verification.Results show that the method of calculating the external capacitance was effective,and the accuracy of charge calculated by the improved calculation model was higher when the windings were close or when the number of turns per unit length was relatively large.

关 键 词：电磁干扰 正激变换器 传导共模EMI特性 共模噪声抵消 

分 类 号：TM46[电气工程—电器]