Volt-VAR interaction evaluation in bulk power systems

This paper presents a novel method to evaluate the Volt-VAR interactions among the buses using relative gain (RG). Following the viewpoint of a multi-input-multi-output system, the Volt-VAR coupling RG is calculated based on the QV matrix which is extracted from power flow Jacobian matrix to evaluate the Volt-VAR interactions among the buses. The voltage stability weak buses are identified through a modified loading margin, and considered as voltage stability critical buses. The proposed evaluation method has great significance for partitioning Volt-VAR control areas in power systems. New England 39-bus system and Polish power system are used to test the performance of the proposed approach. The simulation results verify the effectiveness of the proposed approach in evaluating the Volt-VAR interactions.