High performance DPC for PWM converters

In this paper, direct power control (DPC) method for voltage source converters is described, then a high performance constant switching frequency DPC technique for three-phase pulse-width-modulated (PWM) converters is developed. Hysteresis comparators and switching table are replaced by a PWM modulator and the required converter voltage in each sampling period is directly calculated based on reference and measured values of reactive and active powers, system parameters, and the measured voltage of AC source. Then, the reference voltage is synthesized by the PWM block. In addition to a constant switching frequency, this method lets low sampling frequencies. Simulation results validate the superiority of the suggested DPC.