Variable-Weight Model Predictive Modulation Strategy for A Si-SiC Cascaded H-Bridge Inverter

A Si-SiC cascaded H-bridge (CHB) inverter, due to the redundancy of switching states, can operate with different switching of Si and SiC cells. Therefore, apart from considering the power quality and efficiency of inverters, it also brings the problem of switching between Si and SiC cells. For this, a variable-weight Model Predictive Control (MPC) method is designed to select the overall switch state and assign the switching of cells. A five-level Si-SiC CHB inverter device is built. Compared with fixed weight MPC, the output current THD can be reduced by 1.89% or the device efficiency can be improved by 0.1396%.