Relationship between Finite Control Set Model Predictive Control and Direct Current Control with Duty Ratio Optimization for Power Converters

Among various predictive control methods, finite control set model predictive control (FCSMPC) is famous for its accurate calculating model. Direct current control (DCC) calculates less and thus shortens the processing time. In conventional FCSMPC and DCC, only one voltage vector is applied during one control period, which presents relatively high power ripples. Introducing a zero vector in combination with nonzero vector during one control period can improve the steady-state performance of both approaches. This paper investigates the advantages and limitations of each method with optimal duty cycle control, furthermore, discussing deeply the relationship between two approaches which in some cases they are totally the same. Both simulation and experimental results from a two-level voltage source PWM rectifier (VSR) are confirming the theoretical analysis.