Research And Application Of Comprehensive Evaluation Method For Distribution Network Planning Based On Grid

Distribution network planning is an important guideline for the development of the power grid and a key link in the construction of the power grid.The planning of the distribution network must not only meet the intelligent and refined trend in the development and construction of the power grid,but also meet the needs of users for reliable electricity.The quality of the planning scheme has an important impact on the power supply capacity,operation level,reliability and economy of the power grid.Based on the current background that power supply companies are vigorously pursuing grid planning for distribution networks,comprehensively evaluate grid planning schemes by establishing a scientific and effective comprehensive evaluation system for the distribution network,then it has important practical significance in analyzing the weak links in the operation of the distribution network and determining the effectiveness of the distribution network planning.so as to comprehensively and effectively evaluate the grid planning scheme of the urban distribution network,this paper conducts a fishbone diagram of five important influencing factors,including the power supply capacity of the urban distribution network,grid structure,power supply quality,equipment level,and investment benefits.According to the objects and index levels involved in the evaluation and follow the construction principles of the index system,a comprehensive evaluation index system for grid planning of distribution grids is established,which is scientific,complete and well-defined,and the index definition and calculation methods are introduced.Considering the fuzziness,subjectivity and hierarchy in the comprehensive evaluation process of grid planning of distribution network,a fuzzy comprehensive evaluation model of grid planning based on subjective and objective combination weighting method is adopted.The subjective and objective weights of the indicators are calculated separately through the analytic hierarchy process and the reform entropy weight method,and then the game theory is used to realize the combination of the objectivity of data information and the subjectivity of expert preference.Finally,a fuzzy comprehensive evaluation model is established to uniformly quantify the indicator data,obtain the various indicators of each grid and the overall scoring status.Based on various grid indicators and overall scores,a comprehensive analysis of the current years and planning effectiveness of different grids is carried out,the evaluation results can accurately reflect the weaknesses of the current grid and the planned effectiveness of the distribution network in the target year,also clarify the direction for the planning,construction and transformation of urban power grids.Aiming at the fact that fuzzy evaluation methods cannot solve the problem of duplication of evaluation information and super-fuzzy phenomena caused by correlation between indicators,this paper introduces the gray correlation degree in the TOPSIS method,and combines the Euclidean distance and gray correlation degree to establish a comprehensive evaluation of the grid planning of the distribution network.Compared with the fuzzy comprehensive evaluation method,the TOPSIS method is further improved by using the gray correlation degree.It is possible to calculate the matching degree of each grid before and after planning,and to sort the results to compare the current year and post-planning of different grids.The degree of effectiveness provides theoretical decision-making basis for priority issues of grid construction and transformation and evaluation of planning effectiveness.This evaluation method makes up for the shortcomings of the fuzzy comprehensive evaluation method,and the calculation process is simple,the evaluation results are verified by examples and the fuzzy comprehensive evaluation results are consistent.It can be well used in the evaluation of the distribution network planning and evaluation for the urban distribution network planning.Related research provides more theoretical references.