Study of CM Noise Cancellation in Inverter based on Compensation Principle

Because of the special limitation to the ground capacitance in inverter,it's difficult to cancel the serious Common Mode(CM) noise and the ground current for using large filter.In this paper a passive cancellation method for CM Electro Magnetic Interference(EMI) in power electronic converter is introduced.The new technique for canceling EMI just needs a compensating transformer winding and a compensating capacitor.Since the different structures of the devise result in different paths of CM noise,two EMI compensating ways were chose to compensate the main noise in inverter.This paper also discusses the factors which influence the high-frequency compensation issues and gives effective solutions.Simulative and experimental results approved good effects of these cancellation techniques.