A new fuzzy-based current control strategy with fixed switching frequency for improving D-STATCOM performance

In this study, a novel strategy for current control of distribution static compensator (D-STATCOM) based on fuzzy inference system (FIS) is proposed. The D-STATCOM is utilized for compensating a non-linear load drawbacks in power system by injecting compensating currents. The D-STATCOM is connected between the non-linear load and sinusoidal power source. The control system of the D-STATCOM is designed based on the instantaneous power theory. In addition, two other current control strategies consisting of hysteresis current control (HCC) and adaptive hysteresis current control (AHCC), are investigated and implemented. The results of the HCC and the AHCC are compared with the proposed strategy. Comparison between the obtained results showed that the proposed current control strategy is drastically superior to other strategies due to its less harmonic distortion, lower and constant switching frequency, lower transient current peak and more successful reactive power compensation. The effectiveness of the proposed strategy is verified by extensive simulations in MATLAB/Simulink environment.