| Abstract |
The Near State PWM (NSPWM) method, which has low common mode voltage and low common mode current, is proposed for three-phase voltage source inverter drives. The method is described and its voltage linearity, output current
ripple, DC bus current ripple, common mode voltage and output line-to-line pulse patterns are thoroughly studied and compared with classical PWM methods. The theory, simulation, and laboratory experiments illustrate that in the high modulation index operating range NSPWM has superior overall performance compared to other methods. NSPWM has low common mode voltage and this results in low common mode current. NSPWM has low switching losses comparable to those of DPWM methods, it has low current ripple compared to the classical methods, and it exhibits no significant overvoltage problems in long cable applications as its pulse pattern involves a sufficient distance between the polarity reversing voltage pulses. |
