基于源荷频谱解耦的广域风光中转外送系统长短期储能规划OA

Large-scale development of wind and solar resources in Gobi-desert-barren land areas of Northwest China presents significant challenges to the grid integration of wide-area renewable energy.Supplying flexible resources and realizing bundled delivery via a transit power grid is considered the most practical solution.Focusing on the long-and short-term fluctuations of wide-area wind and solar power and flexibility requirements at different scales,this paper investigates the optimal planning of long-and short-term energy storage.First,a cost-frequency characteristic model for long-and short-term energy storage is established to quantitatively characterize the performance of pumped storage and electrochemical storage and clarify their respective roles.Based on the spectral characteristics of the net load,a source-load spectrum decoupling method is adopted for analysis to distinguish high-frequency and low-frequency ranges and extract typical frequency components.Second,a scenario temporal reconstruction method following source-load spectrum decoupling is proposed.In addition to daily scenarios,a scenario cycle model dominated by low-frequency components is constructed.Third,a system model considering input,delivery cross-section,and transmission channel constraints is established.By incorporating the medium-and long-term demand curves and performance requirements of the receiving-end grid,a multi-timescale operation simulation model for the transit grid is developed,and further an optimal planning model for long-and short-term energy storage is formulated.A case study is conducted on an actual provincial-level system in Northwest China.The results demonstrate that the source-load spectrum decoupling method can effectively identify the core high-and low-frequency components within the net load time-series;long-and short-term energy storage complement each other and are indispensable for mitigating large-scale wind-solar fluctuations;compared with the direct outward delivery of wide-area wind and solar power,the bundled delivery approach via a transit grid yields significantly greater benefits.