分析了三相电压型PWM整流器直接功率控制策略原理,结合整流器直接功率控制的特点,对主电路参数进行了设计和选取。根据PWM整流器在同步旋转dq坐标系中的数学模型,建立了其功率控制模型,并对直流电压外环PI控制器进行了设计。针对传统开关矢量表过多地采用零矢量而导致瞬时功率波动较大和电流波形差的问题,引入优化的开关矢量表。仿真结果表明,优化的开关矢量表克服了传统开关矢量表对瞬时功率控制上的不足,可以获得更好的稳态和动态控制效果。
Analysis was made to the principle of three-phase voltage source pulse width modulation(PWM) rectifier with direct power control strategy.Combining with the characteristics of direct power control rectifier,this paper designed and selected the power circuit parameters.The power control model of PWM rectifier was established according to the mathematical model of PWM rectifier in synchronous dq coordinate,the PI controller of DC voltage outer loop designed.An optimal switching vector table was introduced to solve the problem of larger instantaneous power fluctuations and poor current waveform caused by traditional switching vector because of too much zero vectors.The simulation results indicate that the weakness of traditional switching table for control of instantaneous power is overcome by the optimal switching vector table.Better static and dynamic control effect can be obtained.