Common mode EMI propagation in high voltage DC supplied induction motor drives for electric vehicles application

This paper presents a method for evaluating and predicting the common mode (CM) EMI propagation in high voltage DC-supplied induction motor drives. This configuration represents a typical example of propulsion drive for electric vehicle (EV) applications. In such a drive system the CM currents could have very long transmission routes, leading to radiated EMI noise with potential interference with on board electronic devices. In order to perform an accurate experimental investigations, a new dedicated high voltage (HV) dual DC LISN is disegned and set-up. The CM EMI analysis is performed both in simulation and experimentally. The simulated results are obtained by implementing a high frequency (HF) model of the drive system under study, including the LISN, in a PSpice simulator. The CM currents flowing within the drive system are determined and the CM EMI emissions towards the DC power mains are assessed. Simulated results agree with experimental ones confirming the validity of the proposed modeling of the drive system.