Novel Inverter‐Fed Motor Drive System With Common‐Mode Voltage Suppression and End‐Surge Slew Rate Suppression Function

ABSTRACT Electric locomotives on the horizon will integrate SiC inverters, promising quicker switching and lower losses than traditional setups. However, in addition to the steep rising edge, the inverter‐fed motor drive system faces challenges such as high common‐mode voltage (CMV) and high motor terminal surge voltage swing rate (d v /d t ). To tackle these hurdles, this paper proposes a novel tailored traction control system for three‐phase locomotive motors. This innovative strategy utilises near‐state space vector pulse width modulation (NSVPWM), selectively removing space vectors with high CMV to generate modulation signals. Complemented by a slew rate capacitor configuration, the aim is to reduce CMV while effectively suppressing motor‐side voltage slew rate. To validate this approach, experimental waveforms from on‐site inverter‐fed motor drive systems have been analysed to derive high‐frequency parameters of long‐line cables and variable frequency motors to mimic real locomotive operating conditions better. Through experimental research and comparative simulations against traditional methods, this study reveals a significant 33.3% reduction in CMV compared to traditional systems. Furthermore, it achieves an impressive decrease in the rise/fall slope, down to 86.6%, while ensuring nearly zero electrical power consumption.