Research On The Improved Dynamic Differential Evolution Algorithm In Distribution Network Reconfiguration

Distribution network is an important part of power system, is also one of the most important aspects of the supply power directly to users, its power supply quality directly affects the normal operation of the whole power system. Distribution network reconfiguration is a discrete binary optimization problem, by changing the switch of the open circuit state to adjust the network topology to achieve the purpose of reducing network loss and improving the quality of voltage. So the studies of distribution network reconfiguration and find an optimization algorithm can effectively deal with discrete binary problem ha ve an important practical significance. Differential evolution algorithm is a random search in the continuous space using floating vector encoding optimization algorithm, it is widely used in the field of continuous space problems since its birth. Given the widespread application of differential evolution algorithm in continuous space, so handle a discrete binary optimization problem of the improved differential evolution algorithm also has the vital significance. This article mainly aims at the problems of the improvement of the differential evolution algorithm and distribution network reconfiguration for related research.On the basis of dynamic differential evolution algorithm, two new binary differential evolution algorithms are proposed. By combining the advantages of the two binary differential evolution algorithms, a modified binary dynamic differential evolution algorithm is proposed, which is combined with the time variant linear optimization of the contraction factor and the crossover probability constant. The improved algorithm is tested with 6 classic 0-1 knapsack problems. The experiment shows that the improved algorithm has some advantages in dealing with discrete binary optimization problems.This paper gives a distribution network node layered method, and through the forward and backward method to calculate the power flow. The mathematical model of distribution network reconfiguration is established, which is based on the system active power loss and the minimum node voltage as the comprehensive objective function. A "broken ring" method is proposed, which can eliminate the infeasible solutions produced in the process of reconstruction. Finally, the improved dynamic binary differential evolution algorithm is applied in the distribution network reconfiguration and tested by IEEE33 nodes system and PG&E69 nodes system. Experimental results show that the distribution network reconfiguration can effectively reduce the system network loss and improve voltage quality and the improved dynamic binary differential evolution algorithm in dealing with the problem of distribution network reconfiguration is superior.A variety of distributed generation and the node type of the grid connected interface are introduced. The processing methods of various types of nodes in the power flow calculation of distribution network with distributed generation are presented. A method to calculate the flow of distribution network with distributed generation by forward and backward method is proposed. The mathematical model of distribution network reconfiguration with distributed generation is established with the minimum active power loss as the objective function. Finally, the improved dynamic binary differential evolution algorithm is applied in the distribution network reconfiguration with distributed generation and tested by IEEE33 nodes system with several examples. Experiments show that the distributed generation can effectively reduce the system loss, improved dynamic binary differential evolution algorithm can effectively deal with distribution network reconfiguration with distributed generation problem, also prove that the distributed power supply incorporated into the position of distribution network reconfiguration results have important implications.