On the Enhancement of Power System Operational Performance Through UPFC: A Topological-Based Approach

This paper focusses on how the operational performance of power system networks can be significantly enhanced based on the topology of the network. This enhancement in the operational performance of the network is achieved through the reactive power injection using the Unified Power Flow Controller (UPFC). The mathematical formulations based on circuit theory are presented. The location for the placement of UPFC is determined using an index termed Network Branch Index (NBI). Based on the suitable locations identified using NBI, the influence of UPFC on the operational performance, such as voltage magnitude at every bus of the network and network transmission loss is investigated. A 6-bus system is used to demonstrate the effectiveness of the approach. The simulations are carried out using Power System Analysis Toolbox (PSAT) in the MATLAB environment. The dynamic behavior of the network is investigated when the identified critical line is subjected to contingency analysis. The results obtained show the capability of the NBI technique and also show that there is a significant enhancement in the voltage profile of the network as well as a significant reduction in the transmission line loss when UPFC is placed based on the location identified by the NBI. The results obtained from this study show the role of the network topology in identifying a suitable location for reactive power injections, through FACTS devices, within power systems.