Design method for common-mode electro-magnetic interference filter for motor drive system

Abstract

A design method for a common-mode electro-magnetic interference filter for a motor drive system is disclosed. The common-mode filter is designed based on a transfer function; a common-mode interference source, an interference transmission path and sensitive equipment impendence are taken into consideration quantitatively in topology selection and parameter design of the filter; a target voltage transfer function of different filter topologies is determined according to a reference limit value specified by a voltage source frequency spectrum and electromagnetic compatibility standard firstly; then a filter element value for enabling a minimum deviation between the filter design transfer function and the target transfer function is determined based on a nonlinear least square method; and filter structure and elements finally adopted by the motor drive system are determined according to realizability and operability.

Description

Technical field [0001] The invention relates to a common mode electromagnetic interference filter for a motor drive system. Background technique [0002] Electromagnetic compatibility issues are widely present in various electrical systems, especially in power electronic equipment and systems. In order to suppress the electromagnetic interference conducted and emitted by the high-frequency switching action of power devices, it is usually necessary to install an electromagnetic interference filter, hereinafter referred to as EMI filter. Currently, commonly used EMI filter design methods include: [0003] 1. Try different component parameters repeatedly through experiments [0004] This method is currently the most commonly used, and the advantage is that the design effect is clear at a glance. But the shortcomings are also obvious, that is, the design results come from trial and error, which can neither guarantee the design speed nor whether the design is optimal. [0005] 2. Design...

AI Technical Summary

Problems solved by technology

In order to improve the accuracy of filtering effect prediction, the impedance of interference sources and interference loads can be considered in filter design. This type of method can calculate the parameters of filter components for pre-specified filter topologies with fewer components, but cannot choose Optimal topology, and not suitable for complex system impedance characteristics or application of high-order filters

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