Application of Fuzzy Maximal Tree Clustering for Weak Voltage Buses Grouping

A practical buses grouping method for weak voltage areas based on a fuzzy maximal tree clustering is proposed. Firstly, V-lambda curves of all buses are calculated by continuation power flow method. Then voltage magnitude variation is adopted to find weak voltage buses at the same load variation rate. After sorting the normalized DeltaV in a descending order, the bigger ones are chosen as weak voltage buses. For the voltage magnitude cannot reflect the weakness of the buses, we use the rate of voltage magnitude variation as grouping standard instead and present two indices (in time domain and frequency domain) for weak voltage buses group similarity. After the similarities of the weak voltage buses are calculated, a fuzzy maximal tree is constructed to group the weak voltage buses, while the practical geographic factors are taken into consideration at the same time. Finally, the simulations on IEEE 118 bus system show our configuration method is effective