Optimal network reconfiguration helps with the reduction of total real power losses and the improvement of bus voltages. Several optimal network reconfiguration approaches are available in literature. However, as shown by a very recent study on the IEEE 33-bus radial distribution system, these approaches fail to attain the least total real power losses. Despite that, the recent study did not consider multiple test systems and load variations. Consequently, this article addresses those unexplored areas by introducing an optimal network reconfiguration approach that minimizes the total real power losses in the standard IEEE 33- and 69-bus radial distribution systems under nominal (100%) and heavy (160%) load conditions. The developed approach, which is based on Sparrow Search Algorithm, intelligently searches for the optimum tie and sectionalizing branches that have to be switched on and off, respectively, in order to minimize the systems’ total real power losses. The search for the optimum tie and sectionalizing branches is performed in the permutations of loops created by the radial distribution systems’ tie and sectionalizing branches. For the considered two test systems,  the developed approach gave the least total real power losses and the best bus voltage than the referenced approaches.

This article reports on the development and evaluation of a proposed optimal network reconfiguration approach for total real power losses reduction in radial distribution systems. The proposed approach was developed in MATLAB and the IEEE 33-bus radial distribution system was used in evaluating its performance. Application of the developed approach on the IEEE 33-bus radial distribution system helped to reduce the total real power losses of the system by 76.31%, from 202.68 kW to 48.02 kW, whereas the best approaches reported in literature reduced the losses by 31.15%, from 202.68 kW to 139.55 kW. These results suggest that the approaches reported in literature fail to find the global optimum combination of tie and sectionalizing branches whose corresponding switches have to be closed and opened, respectively, in order to minimize the total real power losses in the system. Consequently, due to its significant reduction of the system’s total real power losses, the developed approach proves to be a potentially reliable tool for power system operators to adopt and use when solving the radial tribution systems’ optimal network reconfiguration problem for real power losses reduction.

The installation of shunt capacitors in radial distribution systems leads to reduced branch power flows, branch currents, branch power losses and voltage drops. Consequently, this results in improved voltage profiles and voltage stability margins. However, for efficient attainment of the stated benefits, the shunt capacitors ought to be installed in an optimal manner, that is, optimally sized shunt capacitors need to be installed at the optimum buses of an electrical system. This article proposes a novel approach for optimizing the placement and sizing of shunt capacitors in radial distribution systems with a focus on minimizing the cost of active power losses and shunt capacitors' purchase, installation, operation and maintenance. To reduce the search space, hence the computation time, the prroposed approach starts the search process by arranging the buses of the radial distribution system under consideration in pairs. Thereafter, these pairs influence each other to determine the optimum total number of buses to be compensated. The proposed approach was tested on the 34- and 85-bus radial distribution systems and when the simulation results were compared with those obtained by other approaches, it was established that the developed approach was a better option because it gave the least cost.