Graph Theoretic Modified Proximity Index Based Approach for Voltage Profile Improvement of Power System

The voltage profile, a critical performance component in any power system, must be contained within a specified tolerance range with regard to the nominal voltage value. Managing reactive power and controlling voltage are crucial factors in electrical power systems. By addressing these issues, it is possible to minimize real power losses as well. Reactive power compensation (RPC) can be done by optimizing size of reactive power sources and optimal location of reactive power sources. There are some graph theoretic indices which determine the location of RPC in order to maximize the effectiveness of these devices in system performance improvement. In this paper, a graph theory based modified proximity index is proposed for voltage control in the power system, and also the voltage profile improvement of power system using this index is compared with that of centrality index. Advantage of proposed modified proximity index is that voltage profile improvement can be achieved by active and reactive load curtailment only unlike addition of reactive power in case of centrality based method. The proposed method is implemented on IEEE 14 bus test system. The proposed method requires a single level of load flow whereas centrality based method requires repeated load flow.