T05.5 - EMI Mitigation in Six-Phase PMSM Drives Using Carrier Phase-Shifted PWM

Electromagnetic interference (EMI) and common-mode voltage (CMV) are persistent challenges in high-speed multiphase motor drives that rely on high-frequency pulse‑width modulation (PWM). This paper studies a six-phase PMSM with 30° inter-winding displacement and demonstrates a software-only mitigation: carrier-phase-shifted sinusoidal PWM (CPS-SPWM) that interleaves the two inverters’ triangular carriers in anti-phase. The interleaving suppresses the dominant switching-frequency group in the conducted-EMI spectrum and delivers a broadband reduction; due to the 30° winding displacement, odd-harmonic components are reduced but not completely canceled. The full paper will incorporate a comparative investigation of SPWM and SVPWM in EMI suppression. The method is experimentally validated on the lab developed AMEBA (A Mechanically Based Antenna) ultra-high-speed PMSM platform. CISPR-style LISN measurements show significant reduction of the switching-frequency peak (5–25 dBμV) over 0.1–1 MHz, achieved without hardware changes or performance penalty.