Comparative performance evaluation of WCA-optimised non-integer controller employed with WPG–DSPG–PHEV based isolated two-area interconnected microgrid system

This study endeavours an effective frequency control of renewable-based isolated two-area interconnected microgrid (ICμG) without battery, incorporating wind power generation in area-1, dish-Stirling solar power generation system in area-2 and other common distributed generation systems such as diesel engine driven generator, plug-in hybrid electric vehicle, heat pump and freezer in both the areas. A recently developed heuristic optimisation technique called water cycle algorithm (WCA) is applied to optimally tune the parameters of the non-integer fractional-order proportional-integral-derivative (FOPID) controllers employed with ICμG. Application of WCA-based FOPID controllers in frequency control two-area ICμG without battery is a novel work. The comparative performance analysis of proportional-integral-derivative (PID), PID with filter and non-integer order-based FOPID controller with their gains tuned by particle swarm optimisation (PSO), improved PSO, firefly algorithm and WCA algorithms indicates the superiority of WCA-based FOPID controller's under different case studies (considering different load disturbances, wind speed variation with real data, and solar irradiance) in terms of frequency deviation, tie-line power, and objective function. Furthermore, the sensitivity analysis contemplates that WCA-optimised FOPID controller can withstand ±25% change in synchronising coefficient, +20% change in loading condition and ±25% change in frequency bias constant without resetting the gain values.