Analysis of split Capacitor based D-STATCOM with LCL filter using Instantaneous Symmetrical Components Theory

Abstract

This paper presents a Four - leg Distribution STATic COMpensator (D-STATCOM) with split capacitor method for a Three-Phase Four-Wire distribution system and a Inductor - Capacitor - Inductor (LCL) filter at the point of common coupling (PCC). In the proposed method, D-STATCOM performs various functions like Reactive Power Compensation, Load balancing, Harmonic mitigation and neutral current compensation with voltage regulation. Interfacing LCL filters between Point of Common Coupling (PCC) and D-STATCOM is employed to attenuate the harmonics in supply currents. Modeling of LCL filter is bestowed and Instantaneous Symmetrical Component Theory (ISCT) is employed for reference source current generation. This method employs sinusoidal pulse width modulation (SPWM) for gating the D-STATCOM. In order to validate the proposed approach, four different cases such as Linear balanced, Non-Linear balanced, Distorted / Varying and Unbalanced loads are considered for simulation. The analysis is validated using MATLAB/Simulink and simpower systems toolbox.