A flexible loss reduction formulation for simultaneous capacitor placement and network reconfiguration in distribution grids

Abstract

Efficiently reducing power losses involves various strategies such as opening normally closed switches and closing normally open tie-lines in distribution feeders, and optimally placing shunt capacitors in distribution networks. In this process, the accurate modeling of the demand side is crucial in understanding the behavior of electricity consumers appropriately. It is important to note that loads are not constant; they vary with changes in voltage magnitude, which in turn depend on the type of consumer. Each load can be represented by its constant power, current, and impedance components. In this regard, establishing a clear relationship between these components and consumer types can significantly enhance the flexibility of the network switching or capacitor placement strategy. Therefore, this study aims to mathematically formulate the correlation between load components and consumer types, aiming at establishing an efficient reconfiguration and capacitor allocation formulations. This is achieved by transforming polynomial load formulations into quadratic ones, while establishing mathematical relationships between the quadratic and polynomial models for various load types. The accuracy and convergence time of the proposed model was tested through its application to 16- and 33-bus distribution networks, and the results have been compared with the nonlinear metaheuristic approach. The results demonstrated that the proposed framework can efficiently provide optimal solutions within a shorter computational time as compared to the nonlinear and metaheuristic approaches.