Analysis of VF-DPC PWM converter based STATCOM

Abstract

The use of STATCOM is a practical method for improving quality of power in distribution systems. In this paper direct power control of three-phase pulse width modulated converter based STATCOM without line voltage sensors is presented. This system is based on virtual flux estimation. Theoretical principles of this method are presented along with simulation results. Advantages of VFDPC-SVM over other DPC techniques presented. The main advantages of DPC-SVM are its simple algorithm, good dynamic response and constant switching frequency operation. This paper compares VFDPC with lookup table and VFDPC with SVM approaches applied to PWM voltage source converters. DPC strategies use lookup table SVM, predictive vector selection or combination of more than one approach for generation of PWM pattern. Power calculations can be done using phase variables or instantaneous power theory. Analysis of VFDPC SVM pulse width modulated converter based STATCOM have been done in MATLAB/Simulink environment. Simulation results are presented. PWM pulses are generated and fed to Converter so as to maintain the power factor of the source at unity. Total harmonic distortion is calculated both in inverter output voltage and source current.