Research on direct power control strategy

High performance control strategies in the PWM converter, main have 2 kinds currently: VOC and DPC. In this paper The principle of PWM rectifier DPC of three-phase PWM rectifiers is analyzed and each part of three-phase control system is also demonstrated in detail. The instantaneous active and reactive power is directly controlled by the hysteresis controller from the appropriate voltage vector selection. The PWM switching signal can be directly obtained through the switching table. It is shown that DPC exhibits several advantages, particularly has no separate PWM voltage modulation block and no current regulation loops, and decoupled active and reactive power control compared to VOC. The simulation results show that unity power factor is achieved and the proposed method has the advantages of low harmonic distortion of current, excellent dynamic-steady state performances, active power and reactive power and also has excellent robustness.