Development of voltage stability index for power system analysis.

Interruption in power delivery is mainly caused by overloading condition in a system and considerably a serious problem. This issue has been a progressing issue in the power engineering community which subsequently motivated further research in the field in order to maintain a secure power delivery. Conventionally, the study of voltage stability utilizes various indices referred to a line or a bus. This paper presents the development of a novel Fast Voltage Stability Index (FVSI) referred to a line. This index is used for analyzing the voltage stability condition of a power system which then helps to predict the occurrence of voltage collapse in the system. The line which gives index value closest to 1.00 will be considered as the most critical line referred to a bus. FVSI is also able to determine the voltage stability limit of a load bus. It was successfully tested and verified on the IEEE 6-bus and 14- bus systems. Results showed that the formulated index is indicative in predicting the occurrence of system violation hence necessary action can be taken to avoid such incident.