Control Method Of Energy Storage Participating In Fast Frequency Regulation Based On Double-Layer Fuzzy Control

With the rapid growth of new energy power generation,in order to meet the growing demand for electricity,due to its own weak inertia and vulnerable to external factors and other characteristics,when its large-scale grid-connected to the power system has brought a series of hazards,affecting the safe and stable operation of the power grid.Thermal power units with low climbing speed and slow response can no longer meet the frequency regulation needs of the system at the present stage.A new frequency regulation method is urgently needed to improve the frequency regulation performance of the power grid.In recent years,the energy storage power technology represented by lithium battery has developed rapidly.In terms of cost and technical factors,it is feasible to participate in frequency regulation.Since the energy storage power supply has the advantages of accurate tracking and quick response,it can significantly improve the frequency regulation capability of the system to assist the traditional frequency regulation unit to participate in the rapid frequency regulation of the power grid.On the basis of systematically summarizing the research status of energy storage power participating in power grid quick frequency regulation and clarifying the main existing problems,this paper focuses on the research of energy storage power participating in power grid quick frequency regulation in four aspects,including control mode,energy storage type selection,equivalent model and control strategy.This paper analyzes the development status of new energy power generation and the impact of new energy large-scale grid-connection on the power system,demonstrates the necessity and feasibility of energy storage power participating in power grid frequency regulation,and summarizes the existing problems based on the current research status of energy storage frequency regulation,so as to determine the research content and technical route of this paper.Based on the frequency regulation principle of power system,this paper expounds the frequency characteristics of load and power supply,analyzes the meaning of primary,secondary and tertiary frequency regulation of power system and the specific implementation mode,studies the advantages and disadvantages of virtual inertia and virtual droop control modes adopted in the fast frequency regulation of energy storage power supply and power grid.Based on several kinds of energy storage power sources that can be used in powergrid frequency regulation,the comprehensive weight method is adopted to evaluate each type of energy storage from the economic and technical aspects,so as to determine the optimal type of energy storage frequency regulation.Based on the study of the existing energy storage equivalent simulation model,a reasonable simplified model is proposed to meet the requirements of rapid frequency regulation of power grid,and then a regional power grid load frequency response model with battery energy storage system is constructed.In view of the shortcomings of the existing energy storage participating in the power grid rapid frequency regulation control strategy.Based on fuzzy control theory.The frequency regulation requirements of power system at the present stage and the next stage are comprehensively considered,and the frequency regulation capability of energy storage itself is also taken into account.According to the fuzzy control rules of stored-energy response power and respondable power,the double-layer fuzzy controller is designed to reasonably control the real-time output of stored-energy,so as to construct the integrated control strategy of stored-energy power participating in power grid’s fast frequency regulation.The rationality and effectiveness of the proposed control strategy are simulated under typical continuous disturbance conditions.