Fast Detection of Voltage Collapse Proximity in Radial Distribution Systems

This paper presents new method for detecting voltage collapse proximity in radial distribution systems. Two indicators for evaluating voltage stability of radial distribution systems were derived. These indicators were based on the reduction of the actual distribution system into two-bus equivalent system. The parameters for the equivalent two-bus system are computed only once at the critical loading at certain bus for a specified power factor. Then the critical loading at this bus at any different power factor can be evaluated using the new indicator. This method is implemented for detecting voltage collapse proximity in some practical radial distribution systems. The results then compared with the results obtained by applying other methods. The comparison showed that the new method gives accurate results despite its simplicity and fastness. This may recommend this method to be applied for investigating voltage stability of radial distribution systems for on-line applications