A Three Phase Power Flow Algorithm for Distribution Network Incorporating the Impact of Distributed Generation Models

The significant penetration of Distributed Generation(DG) systems in electrical power industry is mainly driven by the ever increasing demand for electrical power and growing environmental concerns. Power Flow Studies play a vital role in planning the future expansion of power system as well as for deciding the optimum operation of the existing power system. The ill conditioned nature of distribution system as well as unbalanced nature of DG sources demand unbalanced power flow studies for analysing the DG integrated distribution system. For the power flow studies, DGs can be modelled as either PQ or PV nodes based on the type and interconnection method to the grid. The paper presents an unbalanced power flow algorithm based on the current summation method for the distribution system with the DGs modelled either as PQ or PV node. Handling of PV nodes is done with the help of the sensitivity impedance matrix. The proposed algorithm is validated with IEEE 13 bus distribution feeder