Network reconfiguration for load balancing in distribution networks

Network reconfiguration of a power distribution system is an operation to a lter the topological structure of distribution feeders by changing open/clo sed status of sectionalising and tie switches. By transferring loads from t he heavily loaded feeders to the lightly loaded ones, network reconfigurati on can balance feeder loads and alleviate overload conditions of a network. The branch load-balancing index and the overall system load-balancing inde x are used to determine the loading conditions of the system and maximum sy stem loading capacity. The index value has to be minimum in the optimal con figuration of load balancing. For optimal load balancing condition the bran ch load-balancing indices in the network are to be more or less equal, and also approximately equal to the system load-balancing index. A general form ulation of the network reconfiguration for load balancing is given for the optimal balancing of loads in distribution network and a solution approach is presented. The solution employs a search over different radial configura tions, created by considering branch-exchange type switches. The proposed a lgorithm, called distance measurement technique (DMT) has been developed ba sed on the two-stage solution methodology. The first stage finds a loop, wh ich gives the maximum improvement in load balancing in the network. In the second stage, a switching option is determined in that loop to obtain maxim um improvement in load balancing. The DMT employs a graphical method in whi ch different circles are drawn and the distances of various points from the centre of the loop circle are computed to achieve the optimal or near opti mal configuration for load balancing. The solution algorithm of the propose d method can identify the most effective branch-exchange operations for loa d balancing with minimum computational effort. The algorithm has been teste d with promising results on a 69-bus radial distribution system.