Extended fast decoupled power flow for reconfiguration networks in distribution systems

This study proposes a power flow methodology focused on the need for reconfiguration analysis in modern distribution networks. The proposal is based on the extended fast decoupled Newton-Raphson method, which uses the information of the network switching equipment status (open or closed). To deal with eventual islanding during a reconfiguration procedure, a numerical observability technique used in state estimation analysis has been adapted for topological processing when network segments are disconnected from voltage references. A complex per unit normalisation technique is employed so that the power flow calculation by the fast decoupled approach is viable, even for networks having high R/X ratio lines. Simulation results considering two distribution feeders, one of large size, with different topological conditions are presented. The performance of the proposed methodology qualifies it as a relevant computational tool to support network reconfiguration studies involving emergent distribution systems.