Analysis On Influence Of Distributed Resource Aggregation And Energy Storage Configuration On System Regulation Capacity

With the development of large-scale centralized new energy and distributed energy with large quantity and wide range,the peak-valley difference of load keeps widening,the power grid presents significant "bilateral randomness" characteristics,and the flexibility of the system becomes increasingly prominent.By optimizing the integration of sourceside,network-side and load-side resource,"source-grid-load-storage" interaction becomes an important technical means to cope with the lack of flexibility in high proportion of new energy power systems,and the allocation of flexible resources such as energy storage and flexible loads can alleviate the increasing mismatch between supply and demand of system flexibility.Therefore,in the context of "source-grid-load-storage" friendly interaction,it is important to quantitatively analyze the impact of distributed flexibility resource aggregation and energy storage configuration on improving system regulation capacity to achieve lean flexibility resource allocation.Firstly,for the collaborative optimization problem of distributed flexible resource aggregation and distribution network planning,the reliability requirements of N-1 calibration of main transformer and load secondary transfer of overload main transformer in distributed new energy high-permeability distribution network were considered,and we consider the constraints of distributed flexible resource aggregation on alleviating the influence of regional and seasonal power flow overload,the consumption demand of new energy,and the operation characteristics of distributed resources,a distribution network optimization planning model of collaborative distributed flexible resource efficient aggregation was constructed,and the second-order cone relaxation method was used to solve the model.Secondly,at the transmission grid level,we further analyze the impact of the equivalent flexible load formed by the distributed resources aggregated in the distribution network on the regulating capacity of the system,and establish a three-dimensional domain interval calculation model to quantify the regulating interval of flexible load,energy storage and other diversified flexible resources and the fluctuation range of new energy that can be consumed by the system based on the source-load-storage friendly interactive economic dispatch.The model adopts the pairwise theory to generate a cut-plane constraint excluding infeasible points,and maps the linkage between the regulation interval of energy storage,flexible load and the fluctuation range of the new energy consumable by the system,so as to visually portray the influence of distributed resource aggregation and energy storage configuration on the regulation capacity of the system.Finally,the simulation results of the distribution network case show that considering the aggregation of distributed flexible resources such as distributed energy storage and flexible load,the main substation capacity and inter-station contact structure can be optimized to effectively alleviate the expansion demand of the distribution network expansion plan and improve the support capability of the distribution network for the aggregation of distributed resources;the simulation of the main network case analyzes the spatial distribution of energy storage,new energy,flexible load and the capacity ratio relationship on the system.The main network simulation analyzes the impact of the spatial distribution and capacity ratio between energy storage,new energy and flexible load on the ability of the system to cope with random changes in new energy output,which is conducive to improving the economy of flexible resource allocation planning.