Research On Medium Voltage Substation And Distributed Power Source Location And Capacity Planning Based On Improved Genetic Algorithm

Distribution network planning is an important part of the strategic development planning of power companies.How to carry out scientific and rational medium-voltage distribution network substation site selection and capacity,and build a reliable and economical distribution network.With the widespread growth of distributed generation technology,due to its numerous operational and planning benefits and the penetration of renewable energy,distributed power generation is inevitably included in the distribution network planning model,greatly increasing the complexity of the optimization process.The specific research contents of are as follows:Firstly,the general guidelines for medium voltage distribution network planning are analyzed,and the typical wiring modes of medium voltage distribution networks are compared.The principles followed by the medium-voltage distribution network substation location and capacity are given.calculating the capacity and quantity of substation in the planning level year by calculating the load ratio of the transformer and the simultaneous load of the planned area;summarizing the typical distributed power types and characteristics,introducing the voltage offset of the distributed power supply distribution network The effects of voltage fluctuation,power flow distribution,network loss and reliability result in the positive and negative impacts of distributed power supply optimization on distribution network planning and system reliability,which provides a theoretical basis for subsequent distribution network planning.Secondly,it briefly introduces the genetic algorithm used in the distribution network planning model;then analyzes the coding scheme of the genome in the genetic algorithm.The specific improvement strategy for genetic algorithm;then through the repair of the population and adaptive genetic operators,improve the search ability of the algorithm,so that the decision variables of the chromosome satisfy the constraints while ensuring that the diversity of the population evolves into a planning problem.Finally,the improved genetic algorithm is tested by Schaffer function and Griewank function.The process of search optimization is analyzed.The composition and search characteristics are analyzed.The advantages of improved genetic algorithm for solving distribution network planning problems are obtained.It provides good performance algorithm support for the following medium voltage distribution network substation and distributed power supply location and constant volume optimization planning.Then,establish the optimal site and quantity of the medium voltage distribution substation with the minimum investment and operating costs as the objective function.And the target static annual planning model of the distribution network with the selected transformer capacity;and the improved PRIM algorithm is used to calculate the line path between the feeder line between the high-voltage substation and the medium-voltage substation and the medium-voltage substation to the load center and the load line between the load centers to ensure The radial structure of the distribution network,avoiding the loops in the network and the power supply situation of the isolated islands;through the simulation of MATLAB,the proposed distribution network planning method based on improved genetic algorithm and PRIM algorithm is obtained on the test network.The optimal layout planning scheme of the pressure feeder line adopts the pre-pushback generation method to verify the practicability and effectiveness of the power flow calculation verification plan,and obtains the medium voltage distribution network substation planning method with both economy and reliability.Finally,by analyzing the distributed power supply access network node type and processing method,select the appropriate power flow calculation method;establish a mathematical model of distributed power supply access network location and volume planning considering various constraints;The improved genetic algorithm is used to optimize the distributed power supply access network location and capacity planning.The IEEE33 distribution network node system is used to obtain the planning result through the simulation experiment of MATLAB.The pre-pushing generation power flow calculation method is used to compare and analyze.Before and after the distributed power supply is connected to the distribution network,the parameters of the distribution network are changed.The distributed power supply location and volume planning visualization system based on MATLAB-GUI module is built.The system includes data import,node topology and optimization calculation module.The planning results include distributed power position and capacity information,relevant parameters of the pre-planning and post-planning power distribution system,and realize the basic functions of distributed power source location and capacity planning;through analysis and comparison,the distributed power supply is connected to the distribution network.