| Currently, urban distribution network planning and reformation are proceeding in china, which involve distribution network modeled connection as an important project. It is not only economic, reliable and easy to realize automation, but also significant to the whole electric power industry and customer development. To guide the design of distribution network modeled connection, a series of optimal planning methods are suggested. The main achievements are as follows:The criteria to identify the optimal path of tie lines are investigated. As for a looped grid of "hand in hand", the best planning of tie line is along the shortest route between the tip sections of the two corresponding feeders. The optimal path of a tie line between two sub-sections is the shortest route between the enter points of them.An optimal planning method of tie lines for looped grid of "hand in hand" connection model is presented. Each candidate feeder is regarded as a node of the complementation sub-assembles in a bi-graph. The edges of the bi-graph are established to reflect the possible connections. The construction cost of the shortest route between two nodes is used as the weight of the corresponding edge. The optimal planning result with the minimum total cost can be obtained by using the minimum-weight-matching algorithm. Consequently, the amount of calculation is small.A hybrid method based on genetic algorithm and the minimum weight match algorithm is proposed to reach the optimum planning of the grid with multi-segmentations and multi-connections, in which, the nodes of the two rows of the bi-graph are changed by crossover and mutation operations. Minimizing the summation of the tie line construction cost is defined as the index. The limitation of total investment, the capacity of the electrical equipment and the desired voltage quality are introduced as constraints. In the process, the chromosome is coded with the randomly selected sub-section numbers. Based on the proposed algorithms, the application software is programmed on the platform of VC++, the feasibility of which is tested by practical examples. |
