Application of current control on RV multilevel static compensator for sag mitigation

Abstract

This paper proposes the application of a current mode control on a static compensator (STATCOM). The proposed method uses constant switching frequency. Hence, dominant switching harmonics are filtered easily. This approach is also simple and does not need complex calculations. As a result, it will be an ideal candidate for the implementation of controllers or FPGAs. It should be noted that a single-phase five level reversing voltage (RV) inverter is selected for the STATCOM. The topology has superiorities over conventional multilevel topologies in terms of the control circuit, switching frequency, and the number of components. The simulation results by MATLAB/Simulink prove successful mitigation of voltage sag by the proposed approach. A prototype based on the proposed method is also developed and examined successfully to evaluate voltage sag mitigation. The harmonic spectrum of the STATCOM is also presented to illustrate the equipment compatibility with IEEE 519 harmonic standard.