Research On Reserve Demand Assessment And Reserve Cross-regional Sharing For High Proportion Renewable Energy Power System

In the context of China’s large-scale renewable energy integration into the power system,the uncertainty and volatility of wind power and photovoltaic power have a significant impact on the peak shaving and frequency regulation of the power system,making the consumption of wind power and photovoltaic power the bottleneck of the development of sustainable renewable energy.To address the problem of grid-connected consumption of renewable energy: on one hand,appropriate reserve resources should be set up in the system to reduce the adverse effects of wind power and photovoltaic fluctuations;on the other hand,a global optimization scheduling model should be established from the perspective of renewable energy cross-regional consumption,enabling stakeholders to consume clean energy in a larger area through the coordinated dispatch and time-space complementation of the cross-regional reserve resources.This paper takes the high-proportion of renewable energy grid connection and uneven distribution of regulating resources as the research background,and researches into the high-proportion of renewable energy power system’s operational reserve demand assessment and reserve cross-region sharing.The main contents are as follows:(1)Investigation of domestic and foreign reserve standard is conducted,including reserve classification systems,configuration standards,and reserve standards of renewable energy power systems;then the fluctuation characteristics and forecast error characteristics of wind,solar,and load are analyzed based on historical data;according to the above analysis result,the limitations of the current deterministic reserve configuration method can be evaluated,and the changing characteristics of reserve demand under the situation of large-scale renewable energy system are propose.This chapter paves the way for the refined evaluation algorithm proposed below for system operation reserve requirements.(2)Considering the impact of the uncertainty of renewable energy on the reserve demand of the power system,based on the data mining of net load forecast error(the difference between load and renewable energy power output),a dynamic assessment method,consisting of "curve clustering + multi-scale analysis + scene matching",is proposed for refined and hierarchical reserve demand.The mathematical morphology filter is adopted to evaluate the flexibility resource demand of the system at each time scale,by decomposing the net load forecast error curve into multiple time scales and extracting the fluctuated characterics at all levels according to confidence intervals.(3)According to the concept of the active and reserve joint dispatching of multi-regional interconnected system,the multi-time scale reserve resource constraints are considerated in the power generation scheduling model,and an interconnected grid scheduling optimization model based on hierarchical reserve balance and cross-regional reserve sharing and its solution algorithm are proposed.The research shows that the establishment of refined hierarchical reserve algorithm can improve the operation safety of large-scale new energy power system.Sharing flexible resources across regions can reduce the operating cost of the system and increase renewable energy consumption.