Hybrid EMI Filter for Common Mode Noise Reduction at VSI output

A hybrid EMI filter has been designed to show their effectiveness at improving inverter common mode output noise. The filter has been constructed using the TI TPSF12C1 active EMI filter and the minimal size and amount of passive filter components. Performance tests with and without the active filter enabled show that there is a significant increase in filter performance in the range from 150 kHz to 1 MHz. Additional limit tests of the active filter show that the TPSF12C1 can also effectively be used outside of the manufacturer's recommended parameters. The active filter is still effective when its output is clipping slightly and when a 400 Hz main frequency is used.