INFLUENCE OF FACTS DEVICES ON ELECTRICAL TRANSMISSION SYSTEM

This report contains the study of Flexible AC Transmission System (FACTS) equipment operation in transmission systems. In the present scenario the demand for electrical energy has increased manifold. This has led to the facing of power transmission limitation crisis by energy transmission systems. The limitations occur due to maintaining a balance between supplying the allowed level of voltage and maintaining stability of the system. Due to the power crisis the FACTS devices play a crucial role in the present scenario. In energy transmission systems FACTS are effective equipments on power control. They help facilitating the improvement in power transmission capability while minimising the transmission losses and impact on the environment. They also aid in the improvement of power quality while maintaining the stability of the system.The principal operating modes and applications of FACTS equipment in transmission and distribution system such as Static Var Compensator (SVC), Static Synchronous Compensator (STATCOM), Thyristor controlled series capacitor (TCSC), Static Synchronous Series Compensator (SSSC) and Unified Power Flow Controller (UPFC) is discussed in this report. The characteristics of FC-TCR and UPFC were studied and their models were simulated in Matlab using simulink. In Fixed capacitor Thyristor Controlled Reactor the regulation of power flow was done by changing the firing angle of the thyristor. The compensation obtained was better than that of a normal transmission line. In case of Unified Power Flow Controller the injected voltage and the injected current were the control parameters. The power flow can be regulated by changing the magnitude or phase of the injected voltage while for the injected current the value of the injected current and the shunt resistance are varied for regulating power flow