Effective Strategies for Distribution Systems Reconfiguration Considering Loads Voltage Dependence

The distribution losses significantly affect the system's operational costs and voltage profile that can be reduced by network reconfiguration. However, load power is not constant and can be changed by voltage fluctuation of network buses, in which reconfiguring the topology of distribution systems impacts the magnitude of bus voltages. Accordingly, alteration of nodal voltages affects load amount and subsequent power losses. Still, most of the research works associated with distribution systems reconfiguration have not included load power dependency to nodal voltages in their proposed formulations. Only a few articles have considered voltage-dependent loads in their reconfiguration models but introduced nonlinear formulations or highly approximated linear approaches. While nonlinear models can be solved by metaheuristic algorithms without guaranteeing the optimality of solutions or may be implemented by commercial nonlinear solvers, they require intensive and time-consuming computations. Moreover, linearized models are highly approximated by piecewise linear functions with many unknown parameters. Thus, this paper presents the effective design of the reconfiguration problems, including voltage dependency of loads, which can be solved using commercial linear solvers. The proposed models are precise enough to find accurate results for the reconfiguration problem and are adequately fast to converge to optimal solutions. The results show that the proposed solutions not only reduce active power losses significantly but increase the minimum voltage of the system effectively. Nevertheless, the second strategy presents a better efficiency over smaller networks and provides higher voltage levels.