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Network reconfiguration for loss minimization is the determination of switching-options that minimizes the power losses for a particular set of loads on a distribution system. In this paper, a novel method is proposed by formulating an algorithm to reconfigure distribution networks for loss minimization. An efficient technique is used to determine the switching combinations, select the status of the switches, and find the best combination of switches for minimum loss. In the first stage of the proposed algorithm, a limited number of switching combinations is generated and the best switching combination is determined. In the second stage, an extensive search is employed to find out any other switching combination that may give rise to minimum loss compared to the loss obtained in the first stage. The proposed method has been tested on a 33-bus system, and the test results indicate that it is able to determine the appropriate switching-options for optimal (or near optimal) configuration with less computation. The results have been compared with those of established methods reported earlier and a comparative study is presented. With the proposed method, for any input load conditions of the system, the optimum switching configuration can automatically be identified within a reasonable computer time and hence the method can be effectively employed for continuous reconfiguration for loss reduction. The method can be effectively used to plan and design power systems before actually implementing the distribution networks for locating the tieswitches and providing the minimum number of sectionalking switches in the branches to reduce installation and switching costs. Abstract:Network reconfiguration for loss minimization is the determination of switching-options that minimizes the power losses for a particular set of loads on a distribution system. In this paper, a novel method is proposed by formulating an algorithm to reconfigure distribution networks for loss minimization. An efficient technique is used to determine the switching combinations, select the status of the switches, and find the best combination of switches for minimum loss. In the first stage of the proposed algorithm, a limited number of switching combinations is generated and the best switching combination is determined. In the second stage, an extensive search is employed to find out any other switching combination that may give rise to minimum loss compared to the loss obtained in the first stage.The proposed method has been tested on a 33-bus system, and the test results indicate that it is able to determine the appropriate switching-options for optimal (or near optimal) configuration with less computation. The results have been compared with those of established methods reported earlier and a comparative study is presented. With the proposed method, for any input load conditions of the system, the optimum switching configuration can automatically be identified within a reasonable computer time and hence the method can be effectively employ...

Appropriate size and location of distributed generation (DG) play a significant role in minimizing power losses in distribution systems. This paper represents techniques to minimize power losses in a distribution feeder by optimizing DG model in terms of size, location and operating point of DG. Sensitivity analysis for power losses in terms of DG size and DG operating point has been performed. The proposed sensitivity indices can indicate the changes in power losses with respect to DG current injection. The proposed techniques have been developed with considering load characteristics and representing loads with constant impedance and constant current models, separately. The optimal size and location of DG in a distribution feeder can be obtained through the developed techniques, with minimum effort. The proposed techniques have been tested on a practical long radial system and results are reported. Test results have proven that up to eighty-six percent of real power loss can be reduced with a DG of optimal size, located at optimal place in the feeder.

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Network reconfiguration of a power distribution system is an operation to alter the topological structure of distribution feeders by changing opedclosed status of sectionalising and tie switches. By transferring loads from the heavily loaded feeders to the lightly loaded ones, network reconfiguration can balance feeder loads and alleviate overload conditions of a network. The branch load-balancing index and the overall system loadbalancing index are used to determine the loading conditions of the system and maximum system loading capacity. The index value has to be minimum in the optimal configuration of load balancing. For optimal load balancing condition the branch 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 formulation 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 configurations, created by considering branch-exchange type switches. The proposed algorithm, called distance measurement technique (DMT) has been developed based on the two-stage solution methodology. The first stage finds a loop, whch gives the maximum improvement in load balancing in the network. In the second stage, a switching option is determined in that loop to obtain maximum improvement in load balancing. The DMT employs a graphical method in which dlfferent circles are drawn and the distances of various points from the centre of the loop circle are computed to achieve the optimal or near optimal configuration for load balancing. The solution algorithm of the proposed method can identify the most effective branch-exchange operations for load balancing with minimum computational effort. The algorithm has been tested with promising results on a 69-bus radial distribution system. Abstract: Network reconfiguration of a power distribution system is an operation to alter the topological structure of distribution feeders by changing opedclosed status of sectionalising and tie switches. By transferring loads from the heavily loaded feeders to the lightly loaded ones, network reconfiguration can balance feeder loads and alleviate overload conditions of a network. The branch load-balancing index and the overall system load-balancing index are used to determine the loading conditions of the system and maximum system loading capacity. The index value has to be minimum in the optimal configuration of load balancing. For optimal load balancing condition the branch 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 formulation 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 configurations, created by considering branch-exchange type switches. Th...