Research On Control Strategy And Capacity Optimization About Hybrid Energy Storage System For Suppressing Wind Power Ramp

With large-scale wind power connected with the grid,potential wind power ramp events will lead to imbalance of power supply and affect the security of power system.Hybrid energy storage system is used to suppressing wind power ramp.For the complex wind power ramping evevts,the strategy of scenarios switching adjustment based on the feedback of SOC of battery is proposed.And PSO algorithm is used to optimized the capacity of hybrid storage system.This paper mainly completed the following work:First,characteristics of battery and supercapacitor are compared and studied.Establish the equivalent model of bidirectional AC/DC converter based on SVPWM.A typical model of energy storage unit(storage battery and super capacitor)is completed.Then simulate the model.Secondly,characteristics of the prediction and control methods of the ramping events are analyzed.Based on the prediction,the hybrid energy storage system is used to control the wind power ramp events.The strategy of scenarios switching adjustment based on the feedback of SOC of battery is proposed to ease the complex wind power ramp scenarios.The scene coefficient k is introduced and updated by the method of fuzzy control to not only meet the output power requirements of wind power fluctuation,and can limit the over discharge phenomenon of battery.Then simulate the model to verify the effectiveness of the control strategy.Then,considering the Life Cycle Cost(LCC)and the cost of the operation of wind power ramp control,the overall evaluation model of the energy storage system is established.Based on the control strategy of scenarios switching adjustment,establish multi-objective function of maximum the wind power utilization and minimum the cost.Using PSO algorithm to solve it.The system of energy storage capacity needs smaller.Optimal system economy and the wind power utilization.At last,the whole experiment system is designed and the RT-LAB semi physical real-time simulation platform is built.The effectiveness of the proposed control strategy of wind power generation system and hybrid energy storage system is verified by experiments.