A Joint Source-Storage-Network Planning Method To Deal With Insufficient Flexibility And Transmission Congestion

Vigorously developing wind power generation is an important measure to promote the low-carbon transformation of energy and achieve the dual carbon goal.In the rapid development of wind power,the issue of wind abandonment has been troubling the healthy development of wind power.Wind abandonment is mainly caused by insufficient peak shaving capacity(flexibility)of the power system and insufficient transmission capacity of the transmission channel outside the wind power base.To completely solve the problem of wind abandonment,it is necessary to simultaneously solve the problem of insufficient peak shaving and transmission congestion in the system.As a flexible resource,energy storage can reduce peak load and valley load,reduce the installed capacity of conventional power supplies,and increase system flexibility;It can also reduce peak wind power,relax the dependence of wind power on transmission capacity,and alleviate transmission congestion.Therefore,how to efficiently and comprehensively plan conventional power sources,energy storage,and transmission networks is of great significance for the healthy development of wind power generation and the smooth achievement of the dual carbon goal.In this paper,aiming at the problems of insufficient peaking capacity(flexibility)of power system and insufficient capacity of transmission channel outside wind power base,a series of methods are studied,such as optimal allocation of energy storage and coordinated allocation of large-scale wind power transmission capacity,energy storage in response to insufficient flexibility and transmission congestion,and the joint planning method of source-storage-network considering the coupling relationship of wind curtailment events.From the perspective of energy storage time-sharing multiplexing,the coupling relationship between wind curtailment events is used to solve the problems of insufficient system flexibility and excessive or insufficient transmission configuration faced by large-scale wind power grid-connected transmission network planning,which effectively improves the economy and flexibility of the system.The main work of this paper is as follows:Aiming at the problem of increasing wind power penetration year by year and insufficient flexibility of power system source side,an optimal configuration method of energy storage is proposed to deal with the lack of flexibility of power system source side.Firstly,the mathematical model of flexible resource output is constructed.Secondly,the quantitative analysis of the lack of flexibility of the power system is carried out,and the changes of net load and abandoned wind with the increase of permeability are analyzed.Then the energy storage optimization principle to deal with the lack of flexibility is analyzed.Finally,an energy storage optimization model is constructed to deal with the lack of flexibility.It is verified by an example that the configuration of energy storage can not only improve the system ’s ability to accept wind power,but also improve the economy of system operation.For large-scale wind power transmission capacity is difficult to accurately configure,and the utilization rate of transmission channel is low,and the economy is poor.This paper studies the joint optimization of large-scale wind power transmission capacity and energy storage,reveals the mechanism of energy storage to reduce the power fluctuation of the wind power base and reduce the demand for transmission,analyzes the multi-function cost allocation mode of energy storage,improves the efficiency of energy storage cost recovery,constructs the coordinated and optimized configuration model of large-scale wind power base transmission capacity and energy storage,and realizes the coordinated optimization of transmission capacity and energy storage.Finally,the effectiveness of the method is verified by an example.Aiming at the problem of wind curtailment caused by large-scale wind power integration,a source-storage-network joint planning method considering the coupling relationship of wind curtailment events is proposed.Firstly,from the perspective of time-sharing reuse of energy storage,this chapter constructs a joint planning model of source-storage-network considering the coupling relationship of wind curtailment events,aiming at directly reducing the total wind curtailment of system coupling when configuring energy storage.Secondly,the solution idea and solution steps of the model are given,that is,by modifying the boundary of wind power grid connection point and the feasible region of conventional power installed capacity,the coordinated optimization of thermal power installed capacity,energy storage and expansion of transmission lines is realized,so as to achieve the minimum comprehensive cost.Finally,the effectiveness of the proposed method is verified by comparing and analyzing the planning results of the example system through three methods,which can simultaneously solve the problems of insufficient system flexibility and excessive and insufficient transmission configuration faced by large-scale wind power grid-connected transmission network planning.