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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...

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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...

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Prolonging the network lifetime is one of the vital challenges in wireless sensor networks (WSNs). Typically, the lifespan of WSNs can be increased by a technique called clustering, which plays a significant role in simplifying intra-domain routing. The clustering method accounts only a small number of nodes, which are randomly selected as cluster heads (CHs). The main responsibility of CHs is to receive collected data or information from its member nodes and to aggregate the received data and convey the received data to the sink (Sk) or base station (BSn). In this paper, we have proposed a method namely ''reliability-based enhanced technique for the ordering of preference by similarity ideal solution (RE-TOPSIS)'' combining with fuzzy logic which uses multi-criteria decision making (MCDM) approach aiding in the effective and reliable selection of CHs. It also uses the conventional LEACH protocol to enable one-time CH selection or scheduling in each cluster based on RE-TOPSIS rank index value. This process completely eliminates the need of CH selection process in each round of LEACH's setup state cycle. We have accounted for various criteria such as 1) residual energy; 2) distances between adjacent nodes; 3) energy utilization rates; 4) availability of neighboring nodes; 5) distances between the sink and CHs as well as distances between CHs to member nodes; and 6) the reliability index for completely devising the new scheme. The simulations are accomplished to assess or suggest the performances of the proposed RE-TOPSIS and to compare its performances with the performances of the existing protocols. The results show that the proposed scheme enhances the network lifespan, conserves energy, and introduces a considerable reduction in the frequency of CH selection per cycle by about 20%-25% as compared with the contemporary fuzzy-TOPSIS and LEACH protocols and finally the metrics of the proposed RE-TOPSIS are highlighted.

STATCOM is one of the shunt type FACTS controllers which can supply reactive power and improve bus voltage. STATCOM, a controlling device used on alternating current transmission networks, has advantages like transient free switching and smooth variation of reactive power. This paper proposes a cascaded multilevel inverter type DSTATCOM and DVR to compensate voltage sag in utilities in power distribution network. The proposed DSTATCOM is implemented using multilevel topology with isolated dc energy storage and reduced number of switches. A DVR injects a voltage in series with the system voltage and a D-STATCOM implant a current into the system to correct the voltage sag, swell and interruption. The phase shifter PWM technique is described to generate firing pulse to cascaded inverter. The proposed neuro-fuzzy controller follow itself to the sag and provides effective means of mitigation .The voltage sag with the minimum harmonic at the efficacy end. The proposed technique is simulated using MATLAB/Simulink.