Comparison of Series and Shunt Type FACTS Controller For Voltage Stability Improvement

In recent years, much attention has been attracted to the problems of voltage quality for the electrical power systems. Because of continuous increase of power demands and large scale system interaction as well as the consideration of both the economic benefit and the environment protection, modern power system are operated more and more close to the their maximum operating conditions. As a consequence, some transmission lines are heavily loaded and the system stability becomes a power transfer-limiting factor. In these days, voltage of the system can be control in many ways and the latest technology by using power electronic device that we call as FACTS-devices. Flexible Ac Transmission System (FACTS) devices are the option to mitigate voltage instability by reactive power flow and voltage control criteria. It has lot of configuration like series, shunt etc. TCSC is series type and STATCOM is shunt type controller. In this paper both the devices are compared for voltage stability enhancement.