High frequency modeling of PMSM connected to long cable

In this paper, the impact of suddenly applied dc pulse voltages to the cable-inverter combination is investigated from transient resonance point of view. Irrespective of the rise time, the analysis and simulation ensure the over voltage problem with long cables. A model for cable and Permanent Magnet Synchronous Motor (PMSM) to deal with high frequency emissions from inverter system is proposed and analyzed. The model permits study of the common mode and differential mode effects separately in the rotor reference frame. The experimental measurements show that the motor differential mode stray capacitors are functions of rotor position while the motor common mode stray capacitors are not affected by rotor magnet positions. The simulation results of the proposed common mode and differential mode circuits show that the level of the ElectroMagnetic Interference (EMI) noise currents increased with the cable length. The flow of some differential mode currents in the motor stator windings contribute to torque pulsation which require EMI noise filters to be used.