Mitigating EMI Noise in Propagation Paths: Review of Parasitic and Coupling Effects in Power Electronic Packages, Filters, and Systems

The wide applications of wide-bandgap (WBG) devices in power electronics systems bring benefits in higher switching speed, frequency, and power density, but also cause severe electromagnetic interference (EMI) issues. While many EMI mitigation methods are available to reduce the noise generated from the source (i.e., switching WBG devices), it is equally important to analyze and control the EMI propagation paths. In WBG systems, the parasitic and coupling effects become dominant due to the high switching frequency and the compact system size, which creates uncontrolled propagation paths that degrade the systems’ EMI performance significantly. Therefore, it is crucial to investigate the parasitic and coupling effects and develop corresponding mitigation techniques. This review focuses on analyzing the EMI propagation paths to provide a comprehensive guideline to identify possible parasitics and couplings in the power module package level, EMI filter level, and the power electronics system level. The corresponding mitigation techniques for common-mode and differential-mode conducted EMI as well as radiated EMI are summarized, and the remaining challenges and future research topics are also discussed for all three levels in the conclusion.