Coordinated control of SSSC and SMES in competitive electricity market for load frequency control

This paper presents the Automatic Generation Control (AGC) of an interconnected two-area multiple-units hydrothermal system in a competitive electricity market. In the present competitive electricity market, various kinds of apparatus with large capacity and fast power consumption may cause a serious problem of frequency oscillation. The oscillation of system frequency may sustain and grow to cause a serious frequency stability problem if no adequate damping is available. Moreover, the larger amount of the steam stored in steam chest and reheater of thermal power plant and non minimum phase characteristic of hydraulic turbine delays the control valve motion to increase the mechanical power output after the load perturbation. So in order to stabilize the system, impacts of Static Synchronous Series Compensator (SSSC) in series with tie-line and Superconducting Magnetic Energy Storage system (SMES) at the terminal of area have been investigated. Integral gains of AGC loop and the parameters of SSCS and SMES controllers are optimized through craziness-based particle swarm optimization algorithm in order to have an optimal transient response of the system under different transaction in competitive electricity market.