Simple Explicit Solution of Finite Control Set Model Predictive Control for Cascaded H-Bridge Inverters

In multilevel converters, finite control set model predictive control (MPC) suffers from high computational costs. This article proposes a simple method to reduce the computational burden by solving the equivalent unconstrained continuous control problem, by constraining the solution, and thus by searching the nearest feasible voltage vector. The proposed technique requires a few simple computations that do not depend on the number of levels. An analysis of the computational complexity of the proposed technique is presented and comparisons with other methodologies are discussed. The proposed technique was implemented on a field programmable gate array (FPGA) and tested on a cascaded H-bridge multilevel static synchronous compensator, evaluating the execution time and verifying the validity of the approach.