A comparison of voltage collapse proximity indicators

This paper reviews some important voltage stability indices and presents a new classification of them. These indices can be divided into two categories. The one which is based on the load flow Jacobian matrix can be used to predict the voltage collapse point. The indices in the second category use the elements of the admittance matrix and some system variables such as bus voltages and power flow through lines. These indices require less amount of computing time and are suitable for a fast diagnosis of system condition and contingency ranking, but can not predict the voltage collapse point. The performance of the studied indices is analyzed in IEEE 14-bus test system.