Static voltage stability margin enhancement using shunt compensating devices

Main factor causing voltage instability is the inability of the power system to maintain a proper balance of reactive power and voltage control. The driving force for the voltage instability is the load. Using the shunt compensating devices, the reactive power balance of the power system can be maintained. This paper compares the performance of shunt capacitor, SVC and STATCOM in the improvement of static voltage stability. Issues related to shunt compensation, namely rating of the compensating device and its location are also considered. The performance measures are compared under different operating system conditions for the IEEE 14 bus test system. The analysis presented in this paper uses the voltage stability index (L - index) of load buses, which includes voltage stability information of normal load flow.