Abstract:
This paper presents an impedance shaping technique to reshape the common mode (CM) impedance profile of
three phase common mode choke. The CM impedance offered by
a designed CM choke with specific core area and number of turns
is reshaped using CMIS choke. CM noise in a two level voltage
source inverter (TL-VSI) has dominant frequency components
near inverter switching frequency (Fsw). Attenuation of these
dominant frequency components demand high impedance at Fsw.
A designed CMIS choke offers high CM impedance for Fsw
compared to CCM choke. The proposed three phase CMIS choke
is a passive CM noise attenuation technique that attenuates the
dominant Fsw components. The CM attenuation performance
of passive EMI filter with CMIS choke and CCM choke are
compared for TL-VSI.
