Impact of wind-battery hybrid generation on isolated power system stability

Due to wind fluctuation and load disturbance, energy storage system is required for power stability maintenance in isolated power system. Sodium sulfur (NAS) battery has many virtues which make it attractive for this application. The NAS battery is integrated into wind-battery hybrid generation system through power conditioning system (PCS), which can exchange active and reactive power on both sides for power smoothing. In this paper, the features of NAS battery are investigated and the operation of PCS is introduced. The proposed wind-battery hybrid generation system is modeled and simulated based on PSCAD/EMTDC. Simulation results show that the hybrid generation system can keep the voltage and frequency stability at desired level under the condition of wind variation and induction motor start/stop.