Network reconfiguration for load balancing in distribution networks

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 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...

Power Losses Reduction via Simultaneous Optimal Distributed Generation Output and Reconfiguration using ABC Optimization

“…In the process, switches would be turned on/off to minimize the line loss. Meanwhile, Kashem [2] had proposed an efficient method of identifying the optimum configuration to minimize the power loss. The authors used the combination of tie-switch and sectionalizing for obtaining the best configuration for distribution network.…”

“…Other well-known approaches are through finding optimal DG output and network reconfiguration. For instance, researchers in [1][2][3][4][5][6][7] used reconfiguration approach to improve overall network performance. Meanwhile, researchers in [8][9][10][11][12] minimise power loss by finding optimal location and output of DG units.…”

Study of Network Reconfiguration in Distribution Systems Using an Adaptive Modified Firefly Algorithm

“…In [10], an expert system based on heuristic search was proposed to obtain utilization of the DFR technique in order to reduce the active power losses. In [11], a discrete measurement was proposed to first find a loop in the system (through closing some of the tie switches) and find the best switching scheme to make the system radial. In [12], the DFR technique was applied, to increase the system load balance and service restoration simultaneously.…”

Emergency reconfiguration and distribution system planning under the Single-Contingency Policy

“…By switching on and off lines among substations, load can be transferred from the substation where a transformer fails to its adjacent substations. The concept of emergency reconfiguration was raised decades ago [2], and has been recently implemented in many places with the development of switch technologies [3][4][5]. Therefore, it is interesting to study how emergency reconfiguration affects decisions in distribution system planning and what benefits we can obtain by taking such decisions.…”

“…In spite of many studies on distribution system planning and on operation strategies of emergency reconfiguration [3][4][5][6][7], few of them have considered the two topics together. [1] and [8] consider emergency reconfiguration in substation capacity planning, but they do not further explore the planning decisions' differences nor quantify the benefits induced.…”