Regulating Short-time Wind Power Fluctuation by Variable Speed Pumped Storage Unit

While dynamic regulating effects of pumped storage units have been more and more important in power systems integrated with large-scale wind power, outputs of the conventional reversible pumped storage units still cannot be dynamically adjusted in pumping mode due to the characteristics of pump-turbine. In order to expend the regulating range of reversible pumped storage unit, the variable speed solution is adopted in this paper to realize the dynamic regulating of wind power under the pumping mode. Based on the analysis of pump turbine characteristic curves, the dynamic model and corresponding control strategy of variable speed pumped storage unit are derived. And then, the IEEE 39-bus test system is used to verify wind power regulating performance of variable speed pumped storage unit in pumping mode. The results show that variable speed pumped storage unit has broadened the regulating range of wind power by dynamically adjusting pumping power and effectively reduce the frequency deviation of power system caused by the short-time wind power fluctuation.