Model Predictive Control for Quasi-Z Source Inverters with Improved Thermal Performance

The quasi-Z source inverter (qZSI) is one of the most promising power electronics converter topologies suitable for renewable energy applications. However, as a high-order system, its control is challenging. Recently, the model predictive control (MPC) with several advantages has been applied to the qZSI, where the switching behaviors (counts) are not yet optimized. This paper thus exposes a switching-count-reduction scheme for the MPC used in the qZSI. In the proposed scheme, an optimal switching vector is selected through a multi-parameter optimization, which enables reducing switching counts and thus lowering the thermal stress on the power devices. Simulations have been performed to validate the proposal, which is also benchmarked with several conventional MPCs and the PWM-based control.