Generator Grouping and Voltage Corrections for REI Reduction in Power Networks

This work proposes improvements to the Radial Equivalent Independent (REI) reduction approach originally proposed by Dimo. REI equivalency is typically used for reducing external systems, although other uses have been reported. Some early literature suggests that the REI method may offer reduced accuracy compared to the Extended Ward method. The improvements suggested in this work aim to enhance accuracy and are centered on generator grouping and equivalent system voltage correction. These improvements are tested on an example system subject to typical control center applications such as contingency analysis and load change. The results show that the methods proposed offer significant improvements over the original REI approach.