AMIGO and WC tuning based PID controller design for FESS integrated islanded microgrid

To mitigate frequency deviations occurring in isolated microgrid, this study evaluates proportional-integral-derivative (PID) controller, designed using approximate m-constrained integral gain optimisation (AMIGO) and Wang Cluett (WC) tuning rules. Microgrid model considered for analysis includes both uncontrollable and controllable distributed generation units (DGUs) along with flywheel energy storage (FESS) as energy storing system. Additionally, the first order transfer function of FESS and DGUs, altogether produces a linearised system transfer function. Further for simplifying the analysis of mircrogrid, transfer function is approximated in first order plus time delay (FOPTD) form. The FOPDT model provides system gain, time constant, and delay time. These obtained values are utilised further to derive controller parameters. Tuning rules are implemented to finely tune controller parameters. Frequency analysis and transient response analysis are conducted for AMIGO-based and WC-based PID controllers. The controllers' efficiency and applicability are further clarified by conducting a comparative analysis between AMIGO-based and WC-based PID controllers.