Prediction of voltage collapse in power systems using a reduced system model

The problem of voltage instability in power systems is a growing problem. Fast techniques are needed to predict the onset of voltage collapse so as to avoid any potential widespread loss of power supply. The authors present a new technique for predicting the occurrence of voltage collapse in a power system. Firstly, the mathematical condition for voltage instability is established. A technique for reducing a given power system to a single line equivalent is also described. It is then shown that the parameters of this single line equivalent can be obtained from the results summary of any loadflow study. Finally the authors show how the techniques developed could be used for the practical on-line monitoring of power system voltage stability