An Extension of FBS Three-Phase Power Flow for Handling PV Nodes in Active Distribution Networks

Forward/backward sweep power flow (FBS) is widely used in distribution network analysis because it is very efficient for radial and weakly meshed networks. In these types of methods, sensitivity-based approaches are commonly used to account for PV nodes in active distribution system; however, the convergence deteriorates as the number of PV nodes increases, and may even diverge for large-branch R/X ratios. We propose an efficient method for handling PV nodes based on loop analysis incorporated in the FBS framework. Here, PV nodes refer to nodes connected by distributed generators with constant voltage control. As an extension of FBS, the proposed method´s convergence remains satisfactory when the number of PV nodes increases for a wide range of branch R/X ratios. Numerical simulations with three-phase models were carried out to quantify the performance of the method.