Automatic generation control of single area power system with multi-source power generation

Abstract

In the current paper, automatic generation control (AGC) of a more realistic single area power system with multi-source power generation is studied. The system transfer function model comprises hydro, thermal, and gas power generations with speed governor models and system load for studying the dynamic response for small load disturbances. A proportional plus integral load frequency control scheme is applied only to thermal and gas power generations and hydro is allowed to operate at its scheduled generation level with only speed governor control. Genetic algorithm (GA) is used to optimize the conventional proportional—integral controller gains. Integral squared error (ISE) and integral time absolute error (ITAE) performance indices are used to obtain optimal AGC parameters. The effects on transient performance of the system are investigated for common and individual AGC controller gains of thermal and gas power generations. It is shown that the optimum values of the AGC controller parameters for a single area power system obtained by assuming single source plant dynamics (hydro or thermal) are considerably different than that of a multi-source single area system. The study is also conducted by considering generation rate constraint (GRC) on thermal and hydro generating units. Finally, transient responses are shown for different scheduled loading conditions.