Triangular Fuzzy Number Improved Analytic Hierarchy Process To Evaluate The Voltage Level Of DC Distribution Network

Throughout the development of the power grid,AC transmission and distribution networks have always occupied a dominant position in the entire power system.However,in the long-term development process,the AC network presents problems such as large line losses,high failure rates,tight power supply corridors,voltage fluctuations,and harmonics.With the rapid social and economic development,the energy revolution and the continuous breakthrough of power electronics technology and new materials,as well as the high-quality demand for the future power grid's acceptance of new energy sources for power supply capacity,equipment reliability and high penetration rate,The advantages of DC distribution networks have gradually become apparent.As a major trend in the development of future power grids,the DC distribution network is still in the theoretical research stage,and the study of DC power grid voltage levels is the basis of DC grid planning and the foundation of DC system construction.At this stage,the development of China's large power grid is in the exploration phase of the development of AC and DC hybrid distribution networks.In the future,it may even be possible to achieve the development of DC-based distribution networks.Therefore,this paper is based on the basic principles of the voltage level of the distribution network,and in accordance with the basic laws and constraints,combined with the future development scale of the DC distribution network,establishes a physical model of power supply,combines case analysis,and analyzes the economics of different DC distribution network medium-voltage levels For comparison,it is recommended to choose the medium voltage level that has the most advantages in terms of economy.Based on the economic research,the triangular fuzzy number improved analytic hierarchy process is used to determine the weights of the three indicators of economics,adaptability,and reliability,and the evaluation results are processed using the method to comprehensively evaluate and evaluate the advantages and disadvantages of alternative medium voltage voltage levels.Secondly,based on the load type of the distribution network and the voltage level of the DC power supply system that has been formed,focusing on the applicability,a sequence of recommended low voltage levels for the DC distribution network is given.Finally,the DC power distribution network hierarchy sequence covering medium and low voltage is constructed and the topology structure diagram is constructed,which provides valuable reference for the development of China's DC power distribution network.