Research Of Distribution Power Flow Calculation Method Based On Improved Ant Colony Algorithm

As China's economic development and the people's living standards, as well as electricity load of rapid growth, the electricity demand in the community is gradually increasing. The flow calculation is the most widely, basic, and important type electrical calculation in the power system; The changes of power flow data of distribution network affect the accuracy and the rapidity of the electrical power system automation operation; power flow calculation of the distribution is the most basic part in the distribution analysis; it is an important basic to quantitative analysis the rationality, reliability, and economy of the distribution system programming, network reconfiguration and Operation way. Therefore it is necessary to carry out study on distribution network optimal planning and power flow calculation.In this paper, firstly, the character of distribution network to the algorithm is analyzed. Then, the model of the power flow in the distribution network is created. The development of methods for power flow calculation of distribution network at present have been fully analyzed and evaluated in the aspect of convergence, stability, the ability of multi-mesh processing and capacity of more power handling. Finally it is turned out that the node current injection-type Newton algorithm for distribution network has its advantages.According to the node number optimizing impacts the solution speed of the nodal admittance matrix of power flow calculation, this article studies the principle of optimization of the node number and deeply analysis the application of the node numbering scheme in power flow calculation of a simple radial distribution. A new method of node numbering optimization based on the improved ant colony algorithm is researched, which can import the least nonzero elements in order to quicken the process of solving node admittance matrix. Based on the study of the principle and models of ant colony algorithm it makes improvements for its deficiencies. The algorithm that maximum and minimum ant colony system combining adaptive adjustments the pheromone evaporation factor ant colony algorithm is proposed, which incorporated into the node number optimization of distribution network. Through statistics the number of non-zero elements in each row of the nodal admittance matrix and column number to determine connections between nodes, and the logical vector has used to change the initial search node probability when the ants search the notes in distribution network. At last, the optimal node number has been calculated and prepares for the study of flow calculation. On this basis, the node current injection-type Newton method is used to solve power flow calculation of distribution network.This article uses the matlab language to accomplish the programming, and uses IEEE-28 and IEEE-33 node distribution system to verify the correction of the method. Simulation results show that:The method of node number optimization in distribution network based on adaptive max-min ant colony algorithm proposed in this article is effective. Combine node current injection-type Newton method to carry out power flow calculation of distribution network. This method reduce the convergence times of power flow calculation, which has better numerical stability, and satisfy distribution network in terms of demand trend line.