Study on Hybrid Vector and Sector Optimization of FCS-MPC for PWM Converter

Finite control set model predictive control (FCS-MPC) strategy for power converter system outputs single optimal vector by vector ergodic optimization algorithm, with flaws of low vector control accuracy, unfixed switching frequency and high computational burden for microprocessor. In this paper, a hybrid vector and sector model predictive control (HVS-MPC) strategy is proposed for medium and small power converter systems with high control frequency to improve system performance on three aspects. First, a sector optimization algorithm is adopted to reduce computational burden according to radiation range of basic vector and sector location of target vector. Second, a vector synthesis algorithm is adopted in linear modulation area to improve vector control accuracy with fixed switching frequency by vector operation time calculation and sequence setting. Third, in order to improve system performance in over modulation area without extra computational burden, the hybrid vector modulation algorithm is proposed based on target vector length and modulation area. Finally, the proposed strategy is verified through experiment and simulation.