A modulation method based on finite state machine of five-leg inverter for dual motor drives

Five-leg inverter is a cost-effective solution for dual motor drives. During the operation of the five-leg inverter with conventional PWM method, multiple switching actions occur at the same time in different legs of the five-leg inverter, which causes reverse voltage pulses at the output line voltages and further more results in high frequency harmonic distortion and severe electromagnetic interferences. In order to overcome this drawback, a modulation method based on the finite state machine (FSM) is proposed in this paper, which eliminates multiple switching actions at the same time by optimizing the distribution of voltage vectors. Experimental results show that the independent control of each motor and obvious improvement on the output line voltage quality have been achieved.