| Power system is the most complex system in human society so far.In recent years,the structure of China’s power grid has gradually changed with the advancement of the 2030 carbon peak target.With the promotion of the carbon peak target in 2030,the form of China’s power grid has gradually changed,the new installed capacity of traditional units has gradually decreased,the penetration rate of new energy has rapidly increased,the AC and DC hybrid scenarios are increasing,and the topology of the distribution network has become increasingly complex.Its economic,stable and reliable operation will face severe challenges.Therefore,it is urgent to study the evolution analysis method of the power grid structure,tackle the key problems existing in each side of the source load network during the evolution,explore the evolution and development process of the source load network,and provide theoretical basis and data support for the construction and development of the future power grid.This paper summarizes the research status of power supply structure,load form,transmission and distribution network evolution analysis technology at home and abroad,analyzes the shortcomings of current technologies and methods related to the evolution of power source,grid and load sides to locate the key problems.On this basis,systematic research has been carried out on the theoretical framework,system modeling and evolution analysis of China’s power grid evolution towards 2030.The main contents are as follows:(1)Method for analyzing source-load morphological evolution based on adaptive trend analysis.Aiming at the problem that traditional models are difficult to predict the long-term trend of source load structure evolution due to their short prediction period,limited scope of application and strong sample dependence,an automatic gray-scale discrete prediction model is established.The model parameters are optimized by combining heuristic algorithm and improved least square method.By mining the development trend of source load form,the scale analysis and forecast of load demand in China’s provinces from 2021-2030 are realized.It provides a data base for the evolution analysis of transmission network.(2)Morphological evolution analysis method of transmission network based on spatial-temporal correlation characteristics of new energy and carbon flow distribution.In order to solve the problems of complex spatio-temporal correlation characteristics of new energy output and difficulty in quantifying carbon emission cost in the evolution analysis,an improved ATDGM(1,N)model with multi-dimensional feature sequence is proposed.The multi-dimensional feature sequence is introduced to characterize the strong coupling between new energy sources and improves the analysis and prediction ability of new energy output.On this basis,the power flow optimization model considering the development of source-load pattern and the transmission network planning-operation bi-level optimization model considering carbon emission cost are constructed to realize the analysis of transmission network evolution route.(3)Distribution network morphological evolution analysis method based on adaptive generation of typical source-load scenarios.In order to solve the problems of multiple types,strong uncertainty,single scene generation mode and poor convergence of source and load in distribution network,a source and load prediction method of distribution network based on differential integrated moving average autoregressive method and error gradient sampling method is proposed,and a typical source and load scene of distribution network is generated based on reinforcement learning technology.On this basis,taking into account the regional flexible load demand curve,a multi-stage distribution network planning model is established.The typical operation mode of source load in each scenario and the evolutionary configuration scheme of distribution network in each stage are optimized.(4)A first look at the future shape of China’s power grid in 2030.The morphological evolution of China’s power grid in 2030 is preliminarily explored from the perspectives of source load,transmission network and distribution network.Firstly,the concept of the source load ratio of the sending and receiving provinces is proposed.According to the power and load forecast of each province,the source load characteristics of each province are divided.The evolution of the source load form of each province is analyzed on this basis.Secondly,based on the source load forecast and construction cost data,combined with the development trend of China’s future AC/DC power flow,the scale of AC/DC power flow in each region is calculated.The evolution of China’s transmission network form is analyzed.Finally,a typical region is selected to generate a multi type development scenario,taking into account the impact of multiple factors such as the user type,geographical environment and source load demand in the region.The evolution trend of distribution network morphology in typical regions of China is analyzed under different scenarios.Through the research of this paper,a theoretical framework,system modeling and analysis method for future power grid structure evolution is formed.Furthermore,the evolution path of China’s future power grid form in 2030 is explored based on actual data.It is expected to provide a useful reference for the construction of China’s new power system and help achieve the goal of carbon peak and carbon neutralization. |
