Short-term voltage stability analysis for power system with single-phase motor load

Power system simulation tools have been found insufficient to capture the Fault Induced Delayed Voltage Recovery (FIDVR) phenomena. It is widely believed that this problem is the result of inaccurate load modeling of air conditioner (A/C) loads in the local network. A method is proposed to study the influence of single-phase A/C motor loads on voltage recovery after a transmission line fault. The proposed solution replaces the grid level equivalent load model with detailed single-phase equipment level models of distribution networks in a typical positive sequence power system simulation tool. Local networks with different percentage of A/C compressor loads were built in simulation to study their effects on short-term voltage stability. The FIDVR phenomenon was reproduced successfully in some test cases. The proposed method has been found to be very useful in investigating the actual effect of single-phase motor load on the greater power system voltage stability.