Research On Risk Assessment And Planning Of Distribution Networks Integrating Large-scale Distributed Photovoltaics

The rational planning of large-scale distributed photovoltaics in the distribution network is one of the important factors to ensure the reliable and economic operation of the distribution network.The operational risks of the distribution network have a crucial impact on the planning of photovoltaics.Therefore,this paper conducts detailed research and analysis on the risk assessment and planning of large-scale distributed photovoltaics access distribution network.The main work is as follows:The random models of system components are established in this paper,including the probability models of photovoltaic output and load.The Copula function is used to consider the correlation between photovoltaic output and load to obtain more accurate probability flow calculation information.A risk indicator system of distribution network integrating large-scale distributed photovoltaics is established.The off-limit probability and severity indicator are calculate from the node voltage over-limit and branch flow over-limit respectively to obtain the risk value.The entropy weight method is used to calculate the comprehensive risk indicator.The risk of distribution network operation is more comprehensively and reasonably evaluated.Based on the accurate description of the risk indicator system,the impact of load fluctuations and the different number,capacity and location of distributed photovoltaics on the risk value are studied.The relationship between the above factors and the risk value is qualitatively and quantitatively analyzed.To a certain extent,it provides theoretical value for reducing the risk of distribution network.Finally,based on the risk assessment,considering the penalty cost of the risk of node voltage over-limit and branch power over-limit,with the goal of maximum comprehensive income,a large-scale photovoltaic planning model is established.The improved adaptive genetic algorithm is used to solve the planning model to achieve the optimal planning of large-scale photovoltaics in the distribution network.System simulation analysis based on MATLAB verifies the feasibility and effectiveness of the above risk assessment methods and planning models.