L-Index Sensitivity Based Voltage Stability Enhancement

Voltage stability is a long standing issue in power systems. Due to the requirements of on-line monitoring and high computation efficiency, L-index is used as voltage stability metric in this paper. We propose a novel L-index sensitivity based control algorithm for voltage stability enhancement. The proposed method uses both outputs of wind generators and additional reactive power compensators as control variables. The sensitivities between L-index and control variables are introduced. Based on these sensitivities, the control algorithm can minimise all the control efforts, while satisfying the predetermined L-index value. This paper then verifies the proposed voltage stability enhancement method using real load and wind generation data in the IEEE 14 bus system. The simulation results prove the effectiveness of proposed methodology in enhancement of voltage stability.