Application of DSTATCOM for power quality improvement using isolated zig-zag/star transformer under varying consumer load

The demand of non-linear and dynamic load is increasing day-to-day causing severe power quality issues. This paper presents a novel control strategy by employing distributed static compensator (DSTATCOM) to mitigate power quality problems. The proposed controller is a combination of a DSTACOM consisting voltage source converter with zig-zag/star transformer for optimizing DC link voltage. The DSTATCOM is realized by using IGBT based current controlled voltage source converter, which inject the reactive power. The neutral point for consumer load is provided by zig-zag/star transformer which mitigates the harmonic current, provide the path for zero sequence current, provide isolation for power electronics devices and optimize the DC link voltage of DSTATCOM. Power balance theory (PBT) is employed for generating gating pulse of DSTATCOM under varying consumer load. This concept is demonstrated with various MATLAB/Simulink simulation studies. Finally a comparative analysis is carried out to show the effectivity of the proposed controller.