Research Article Open Access

AGC in Multi Area Multi Source Deregulated Power Systems with AC & DC Tie

Abstract

A suitable mathematical model of Thermal-Hydro (T-H), Thermal-Hydro-Gas (T-H-G) Automatic Generation Control (AGC) system under deregulated environment was presented in this paper. The variable power consumption as well as intermittent load variation may cause large fluctuations on system frequency. To reduce the system oscillations, HVDC transmission link between two areas which can allow sudden variation of tie line power can be applied. The system transfer function model comprises thermal, hydro and gas power generations with governor models and system load for studying the dynamic response for small load perturbations along with the model of HVDC transmission link. Integral controllers have been considered in both the areas whose optimal values are obtained by minimising the Integral Squared Error (ISE) technique. The particle swarm optimization (PSO) is applied to solve the control problem to achieve the controller parameters and also to optimize the Integral Controllers of two area power system in deregulated environment. The dynamic responses without and with HVDC link are compared. Simulation studies reveal that with the application of the HVDC link, there is an improvement in AGC in terms of peak amplitudes and deviations in frequencies of both the areas.

K. Hari Krishna, K.Chandrasekhar