FVSI Based Meta-heuristic Algorithm for Optimal Load Shedding to Improve Voltage Stability

When a disruption, increase in load demand, or change in system circumstances occurs, a system goes into the state of voltage instability. In this paper, an integrated and effective framework for voltage stability assessment based on Voltage Stability Indices(VSI) and voltage stability improvement using optimal load-shedding is proposed. Several VSIs have been utilised to compute proximity to voltage collapse, maximum loading capability and identification of weak buses/lines. Load-shedding is used as a control method to stabilize the system if the load on the weak buses increases. The proposed approach employs Fast Voltage Stability Index (FVSI) to identify the weak buses in the system subjected to different loading scenarios. The FVSI based optimal load shedding is then proposed using Particle Swarm Optimization (PSO) and Grey Wolf Optimization (GWO) meta-heuristic algorithms. The technique has been tested successfully on the standard IEEE 30 bus test system.