Pulsewidth modulation method to balance the loss distribution of dual inverter to drive open-end winding motor

A pulsewidth modulation method is proposed to balance the distribution of semiconductor losses in a dual inverter to drive an open-end winding motor. This method can mitigate an unbalanced loss distribution between the upper and lower switch modules by adjusting the allocation of the voltage references to each of the sub-inverters, which are split from the voltage references of the motor. While the reference allocation is explained with splitting space vectors, the proposed method can be easily implemented with carrier waves. In addition, a method to utilize the reference allocation for balancing the loss distribution is discussed. First, the feasibility of the proposed method is examined with simulation results obtained from the entire range of the first-quadrant operation for a target motor. Experimental results are then presented and assessed to evaluate the effectiveness of the proposed method. As a result, the maximum temperature rise of a switch module under power conversion can be reduced by 18.1% under one of the worst conditions.