Modularized Model Predictive Control Scheme with Capacitor Voltage Balance Control for Single-Phase Cascaded H-bridge Rectifier

Modularized model predictive control (MPC) with capacitor voltage balance control for single-phase cascaded H-bridge (CHB) rectifier is proposed. The sampling period is divided into equal intervals and the optimization problem for one cell can be solved in each interval so that it can be extended to multi-phase and multi-level CHB rectifier easily including capacitor voltage balance control. The optimized modulation function for SPWM/SVPWM is used to reduce steady-state current error and obtain constant switching frequency. Capacitor voltage balance control is realized through the modulation function of each cell separately by choosing different λ. In addition, instantaneous α-β current component for single-phase CHB rectifier is generated by second-order generalized integrator (SOGI).