Dynamic Modeling and Controller Design of Distribution Static Compensator in a Microgrid Based on Combination of Fuzzy Set and Galaxy-based Search Algorithm

This paper presents a nonlinear controller for a Distribution Static Compensator (DSTATCOM) of a microgrid incorporating the Distributed Generation (DG) units. The nonlinear control has been designed based on partial feedback linearization theory and Proportional-Integral-Derivative (PID) controllers try to adjust the voltage and trace the output. This paper has proposed a combination of a fuzzy system and Galaxy-based Search Algorithm (GbSA) to optimize the parameters of the PID controllers. The results confirm that the characteristics of the response of the proposed controller (i.e. settling and rise times, the maximum overshoot and the steady-state error of the voltage step response of the DSTATCOM) is significantly improved by finding a high-quality solution. The proposed hybrid tuning method for the Partial Feedback Linearizing (PFL) controller concluded a better DC voltage regulation for the capacitor within the DSTATCOM. Furthermore, in the event of fault the proposed controller tuned by the fuzzy-GbSA method has shown a better performance in comparison with the conventional controller or controllers tuned by Genetic Algorithm (GA) or Particle Swarm Optimization (PSO) methods on both fault duration and after clearing times.