AVOA-based PID+IDF controller for frequency control of isolated hybrid thermal power system

Abstract

This paper presents a load frequency controller (LFC) of an isolated hybrid thermal power system (IhTPS) integrated with a distributed generation unit to reduce frequency deviations (FD) that appeared after adding the load demand and wind power fluctuations. A proportional-integral-derivative plus integral-derivative filter (PID+IDF) controller is proposed as an LFC or a secondary controller in the frequency control area to eliminate the FD and steady-state error of the IhTPS response. To obtain an optimistic result of IhTPS, a recently developed African Vultures optimization algorithm (AVOA) is used for proper tuning of the controller gains by minimizing the integral of time multiplied absolute error criterion. The efficacy of the optimized PID+IDF controller performance is examined by considering different case studies. It is observed from simulated system results that the proposed AOVA-optimized PID+IDF controller delivers better performance in terms of fewer oscillations, lower peak under/overshoots, and settling time of FD. Further, the sensitivity analysis is performed to validate the robustness of the proposed controller in the presence of random wind speed and parameter uncertainties.