Common Mode Noise Cancellation by Two Opposite-Phase-Operating Inverters for Motor Drive

In motor drive inverters, the switching operations associated with rapid voltage potential change, and flows through parasitic capacitors may cause serious conducted common noise problems. The conducted noise emission introduces interference to other circuits, and therefore should be reduced. In this paper, a technique to suppress common-mode conducted noise is proposed that two inverters are operated in opposite phase. They generate opposite phase common-mode noise, and therefore the noise can be cancelled. The effectiveness of the proposed method is verified by experiments and simulations.