Research On Energy Storage Battery Participating In Primary Frequency Control Strategy Of Power System

As global energy demand increases,fossil energy that people rely on is continuously mined and consumed,and now faces energy shortages.At the same time,increasingly serious environmental pollution pro blems have made renewable energy into the people's field of vision.However,the incorporation of a large amount of renewable energy into the power system has also created new problems,and the stability of frequency has become one of the concerns.When energy storage technology develops,the advantages of energy storage are increasingly recognized,and its role in grid frequency stability has gradually been used in practice.How to control the storage energy to play a greater value in the primary frequency regulation of the power grid is particularly important.Based on the research status of energy storage participating in frequency modulation,this paper focuses on the problems of control strategy in energy storage participation in primary frequency modulation,and studies on these issues.Firstly,based on the basic principle and simulation model of power system primary frequency modulation,an equivalent model of energy storage battery suitable for primary frequency modulation is established.Finally,th e energy storage participation in the grid primary frequency equivalent model is established.Two control methods are used to construct energy storage.On the basis of participating in the FM transfer function,the advantages and disadvantages of the two a re compared and analyzed: the energy storage using virtual inertia control plays a role in the frequency change process,which not only suppresses the frequency deterioration but also hinders the frequency recovery.In steady state,the energy storage can not play a supporting role.The energy storage with virtual droop control can play a role in both frequency transient and steady state,and has no shortcomings that hinder the frequency recovery.It can fully utilize the energy storage response speed and a ccuracy.Control and other advantages;analyze the problems existing in the current research from two aspects of FM demand and recovery demand.Secondly,the characteristics of ultra-short-term load forecasting and its application in frequency modulation are expounded.The fuzzy control method is used to obtain the recovery criterion of energy storage state to reduce the influence of prediction error.Consider the energy storage battery SOC design energy storage.Under the premise of considering ultra-short-term load forecasting,combined with FM demand and recovery demand,it is proposed that when the frequency is outside the frequency dead zone,the energy storage is only frequency-modulated,and the internal energy storage is restored.The energy storage and conventional unit coordinated control are proposed.Strategy;and the typical regional power grid as an example,the proposed strategy and the conventional control strategy are simulated under two typical conditions,which proves that the proposed stra tegy can coordinate the energy storage with the traditional unit for SOC recovery during the recovery period.The control strategy has an advantage over its improved frequency modulation and energy storage battery SOC retention.Finally,the relationship between the climbing rate of the traditional generator set and the system frequency is analyzed from the two aspects of energy and power,and then the system frequency enters the frequency dead zone,the system frequency is not in the frequency dead zone,but the traditional generator climbing rate tends to zero.In this paper,the recovery timing of energy storage SOC is studied.The energy storage frequency modulation strategy based on fuzzy control and the energy storage SOC adaptive recovery strategy considering energy storage capacity limitation are established.A storage energy frequency modulation synthesis considering traditional unit climbing rate is proposed.Control Strategy.The proposed strategy and the traditional control strategy are simulated under typical conditions,and the superiority of the strategy is verified.