Frequency control of an isolated power system considering mutual effects of AGC in presence of energy storage units

Automatic generation control (AGC) of an isolated power system is investigated in this paper. Performance analysis is carried out by considering the mutual coupling effect between load frequency control (LFC) and automatic voltage regulator (AVR) control loops by adding one fixed and one variable energy storage systems (ESS). The insertion of storage devices reduces the frequency oscillations for various load changes and also reduces the mutual effect of LFC and AVR. Simultaneous coordinated tuning of secondary controller and variable storage unit with particle swarm optimisation (PSO) and improved particle swarm optimisation (IPSO) is carried out to provide control strategy for the system. The system is simulated both in presence and absence of secondary controller in which IPSO gives better performance results than PSO. The simulation is carried out in MATLAB/Simulink software.