Model Predictive Control based Discontinuous PWM Algorithm for 3L-NPC Inverter

This paper proposes a novel model predictive control based discontinuous PWM strategy for 3L-NPC inverter. Through the model predictive control principle and special output level sequence arrangement, the optimal voltage vector and zero sequence voltage are selected, so that the neutral point voltage can be controlled on the basis of discontinuous modulation strategy, thus achieve the purpose of balancing the neutral point voltage and reducing the switching loss. Because there are most three elements in the control set, the calculation of this method is quite simple. Compared with carrier based PWM and space vector PWM, it does not need vector synthesis and complex zero sequence voltage calculation, so it is easy to implement. Experimental results verify the validity of the method.