Simulation Research On Smoothing The Wind Power Fluctuation By Using Energy Storage System

Wind power connected to the grid is an important way to develop and utilize wind power in large-scale, response to the challenge of reducing emission of power system. Because of the randomness of wind energy, the output power of wind turbine is fluctuant, which leads to lots of adverse effects on the grid. In order to solve the problem of wind power fluctuation, the method of using storage system to smooth the power fluctuation is taken into account. Due to the high cost of energy storage system, so how to use energy storage system in limited capacity to improve the output power quality of the wind power is becoming an important research subject.Based on the analysis of wind power fluctuation characteristics and combined with the current development status of wind power generators and energy storage technology, this paper presents a kind of flexible wind power generation system which is composed of the double fed wind generators and central battery energy storage system. This kind of flexible wind power generation system can make full use of energy storage capacity.The control strategy for smoothing the wind power fluctuation is designed based on the principle of low-pass filter, and the storage capacity algorithm for meeting energy requirement of smoothing process is also designed.In addition, the indicator for evaluating smooth control effect is built. Through the simulation examples, the validity of control strategy is verified and the relationship between smooth control effect and energy storage capacity is briefly analysed, which can supply references for energy storage system configuration of wind farm.In this paper, because of smoothing the wind power fluctuation depending on the rapid charge and discharge control of battery energy storage system that realized throuth the converter power control, the active and reactive power control method of converter based on feed forward decoupling control is discussed. Based on PSCAD/EMTDC, a simulation platform for the operating control of battery energy storage system is set up. Throuth the operating control simulation examples, the validity of the proposed control method is demonstrated.