Analysis of Capacitive and Inductive Coupling inside Hybrid Integrated Power Electronic Module
Electromagnetic compatibility has to be given enough attention in the design of hybrid Integrated Power Electronic Module (IPEM) due to the sharply decreased distances between power devices and the control/driving circuits as compared to such distances for conventional power electronic equipment built with discrete devices. The high dν/dt, di/dt and high frequency parasitic ringing emanating from the switching circuit can cause serious EMI within the control/driving circuit due to cross-coupling. This paper analyzes the capacitive and inductive cross-coupling problems inside an IPEM. Finite Element Method (FEM) is used to extract the mutual capacitances between the metal bars in the model. Then the influence of dν/dt can be estimated. The high frequency circulating current in the bridge circuits is also investigated since it causes magnetic interference due to mutual inductance coupling. The mutual inductance is calculated with the simplified Partial Element Equivalent Circuit (PEEC) approach and image method. The experiment validates the effectiveness of this evaluation. In the end, the electromagnetic shielding is discussed.