This paper presents the impact of energy storage on the responses of two-area thermal power systems connected via a tie-line. Improving system parameters such as frequency deviation and tie-line power deviation are key objectives of the analysis. Controller parameters are optimized by genetic algorithm (GA) technique. An enhanced Fuzzy-PID controller is proposed, which delivers better response compared to conventional Integral and PID controllers. In this study energy storage devices such as superconducting magnetic energy storage (SMES) and capacitor energy source (CES) are utilized as tertiary control mechanisms to improve system responses. A detailed comparative analysis is performed for energy storage devices as well as for controllers.

The power system operation needs to keep the harmony among the power generation and demand, failing which will leads to sudden rise and fall of frequency as well as transient tie-line power. AGC is one of the significant control phenomenon in power system, for control of frequency and power in an interconnected system. This paper presents the details of issues related with specific controlling techniques used in AGC at the past and with what control we can rectify those issues in future. This paper also presents a brief review of the controlling methods that has been exercised to automatic generation control (AGC) from the primeval time to the modern day. Review related to literature work of AGC in deregulated environment has been presented.