Direct power control with constant switching frequency for PWM rectifier

In order to overcome the unstable frequency of traditional direct power control switching,a novel and simple direct power control of three-phase pulse-width-modulated rectifiers using space-vector modulation(DPC-SVM) was introduced.The line voltage sensors were replaced by a virtual flux estimator.The instantaneous power theory was applied to calculate the active and reactive power by estimating the virtual flux,the voltage of outer and inner power control mode was adopted and a simulation study was done.The results show that the application of DPC-SVM make the system own the features,like simple structure and algorithm,good dynamic response,high power factor,constant switching frequency and low harmonic.