Identification of the weakest bus in a distribution system with load uncertainties using reactive power margin

Recently, establishing reliable index to assess voltage stability condition of a stressed multi-node power transmission and distribution system is getting lot of attention. With the integration of renewable energy in power system the subject of voltage stability in distribution system is getting more interest. In this study, reactive power margin has been used as a stability index which appears as a reliable index to determine critical or weak node while considering the influence of load uncertainties. Effectiveness of reactive power margin index has been proved using a modified 16 bus primary distribution system. Some important results are presented in this paper.