Review of Conducted EMI by Different PWM Schemes in the EV Inverters

The advent of wide-bandgap (WBG) switching MOSFET devices enables high-frequency operation, allowing for significant reductions in the size of passive components such as inductors and capacitors, and improving the overall efficiency of inverter systems. However, these benefits come with the trade-off of increased electromagnetic interference (EMI), which imposes stringent requirements on filter design. The complexity of designing EMI filters, which depends heavily on switching frequency and applicable EMI standards, presents a significant challenge and can impact development timelines. Carrier wave modulation technique is considered as an effective method for minimizing conducted EMI in traction inverters. This article presents various carrier wave modulation schemes that successfully reduce conducted EMI. The evaluated strategies aim to eliminate noise fluctuations and simplify the design of demanding EMI filters. Additionally, the impact on output voltage, output current, total harmonic distortion, and overall inverter performance has been analyzed. The results demonstrate that the discussed carrier wave modulation techniques can reduce conducted EMI more efficiently than conventional carrier frequency PWM methods.