A basic study on inverter output filter for radiative noise suppression

Power electronic technology enables high efficient motor driving and it will continue to expand. When the use of more high speed switching device will expand, increase in the emission level of radiated electromagnetic interference (EMI) may become a problem. This paper deals with radiated EMI generated by power electronic equipment. A noise evaluation model, which is made on the supposition of an AC motor drive, has been used for measurement of the noise spectrum in a radio semi-anechoic chamber. Comparison between the experimental results and the simulation results confirms validity of the simulations using an electromagnetic analysis software. Electromagnetic field simulation results using conventional countermeasures against EMI for noise evaluation model are shown, a new radiative noise filter is proposed, and noise suppression effect of the proposed filter is confirmed by electromagnetic field simulations.