Simple Algorithm with Fast Dynamics for Cascaded H-bridge Multilevel Inverter based on Model Predictive Control

Model predictive control (MPC) method with finite control set needs calculations according to the total number of voltage vectors made by multi-level converters. This operating principle of the MPC tends dramatically to increase the computational load and number of calculations when the level of cascaded H-bridge (CHB) inverters is increased. A new MPC algorithm is proposed in this paper for decreasing the number of calculation in multi-level CHB inverters, in which only three voltage vectors are evaluated to determine optimal vectors regardless of the level of CHB inverters. As a result, the proposed MPC method needs fewer calculations and decreases the computational load compared to the conventional MPC method for CHB inverters, without affecting the performance and dynamic response of 5-level CHB inverter.