Dead-time elimination and zero common mode voltage operation of neutral-point-clamped inverter

This paper presents the dead-time elimination scheme for modulating neutral-point-clamped inverter. Unlike the dead-time compensation methods reported for mitigating negative effects induced by dead-time insertion, the proposed scheme simply separates each pair of switches by treating every switch independently and triggers the corresponding switches per phase according to the judged current direction. The removal of dead-time interval, together with the introduction of an appropriate modulation scheme, can then help mitigate switching common mode voltage, even without those narrow alternating spikes generated by common dead-time insertion in traditional pulsewidth modulation (PWM) techniques.