Optimal Planning & Partitioning Of Urban Distribution Networks Based On GIS

An optimal planning scheme of urban distribution networks is presented. An urban distribution network is firstly divided into several distribution sections, and then a Minimum-Cost Spanning Tree(MCST) based approach is adopted in each distribution section to obtain a radial grid, at last the sectionalizing switches and loop switches are planned. The main achievements are as follows:A heuristic method to optimally divide an urban distribution network into several distribution sections is put forward. A street division is considered as the minimum unit. The core street division is selected. The index of load balance in the distribution sections is used. The limitation of supplying radius is introduced as a constraint. The main procedure of partitioning of distribution network is merging the adjacent street division and making adjustment on the results. The load in each distribution section is guaranteed to be close. Consequently, the reserve capacity of electrical apparatus can be decreased.An improved Minimum-Cost Spanning Tree based algorithms for distribution network planning is investigated. The load points are regarded as vertexes. The routes, along which, feeder lines might be implanted are regarded as edges. The summation of construction cost and operational cost of each feeder is defined as the weight of the corresponding edge. Based on the preliminary planning results of basic MCST algorithm, by adjusting the weights of each edge dynamically and implanting an iteration method, the optimal planning result of the minimum total cost is obtained. Cross points are well dealt with. A street map is designed to help implanting lines. The relation between the load points, the cross points and source points is found out to complete implanting lines.The principle of installing sectionalizing switches and loop lines is presented. The feeder is divided to three sections to average the feeder load. Find the shortest path between the ends of two feeders and take it as loop line.Based on the algorithms noted above, a practical program is written out in VC++ language. The program could aid people in making plans of urban distribution networks directly on the map with the help of GIS. An example is given showing the feasibility of the proposed methods and program.