Research On Wind Power Stabilization Based On Fuzzy Adaptive Control

Under the background of energy crisis and energy conservation and environmental protection,the new energy power generation industry represented by wind power is developing rapidly.The global total installed capacity of wind power is increasing year by year,and the penetration rate of wind power in power system is increasing.However,due to the randomness and unpredictability of wind energy,it has a huge impact on the safety and stable operation of power system after grid connection.The phenomenon of power restriction and wind abandonment is very serious.Therefore,it is of great practical significance to study how to reduce the fluctuation of wind power output and connect to the grid safely and stably.This thesis takes doubly fed generator as the research object.A hybrid energy storage system composed of battery and super capacitor is selected to stabilize the wind power.Through the improved particle swarm optimization,hybrid energy storage capacity is configured.Based on the frequency division coordination control strategy,fuzzy algorithm is added.According to the reference power and the state of charge of storage battery,the optimal distribution of the throughput power of the whole energy storage system is completed among different energy storage devices,and the coordinated control between the energy storage system and the wind power generation system is realized.The wind power is suppressed and the service life of the battery is improved.The details are as follows:1.The operation principle and topological structure of the doubly fed generator are analyzed systematically,and the mathematical model of the doubly PWM converters are established.The grid voltage directional control strategy and stator voltage directional control strategy are designed to realize the control of grid side and rotor side converters.Through the simulation platform,the step wind speed and the random wind speed are respectively given to verify the correctness of the doubly fed generator model and the control strategy.2.Based on the hybrid energy storage system framework composed of battery and super capacitor,the mathematical model of grid connected energy storage inverter is established,and PQ control is used to realize the flow of energy between AC bus and energy storage system.In order to improve the economy of hybrid energy storage,particle swarm optimization(PSO)is improved to optimize the capacity allocation of hybrid energy storage system.According to the performance characteristics of the battery and the super capacitor,a coordinated control strategy is designed.The low frequency part is suppressed by the battery,and the high frequency part is suppressed by the super capacitor,and the voltage and current double closed-loop control is adopted.The simulation results show that the power fluctuation of wind power generation is effectively suppressed.3.Based on the frequency division coordinated control strategy,an adaptive fuzzy control based on feedback of state of charge of battery is proposed.The fuzzy controller is designed to optimize power distribution according to reference power and state of charge of battery.The simulation results show that,the proposed controller can effectively suppress the power fluctuation,improve the state of charge of battery,ensure the safe operation of the battery,and extend its service life.