Multiphase power flow and state estimation for power distribution systems

A multiphase power flow model and state estimation for distribution systems are formulated and solution methods are presented. The multiphase power flow model is based on fully asymmetric modeling of the power distribution system. The state estimation uses this model in conjunction with synchronized measurements. The method provides an estimate of the total electric load for each distribution circuit without the requirement of knowledge of the individual loads along the circuit. The paper addresses the following issues: (a) modeling; (b) implementation; (c) observability; and (d) performance. The overall performance of the method is described in terms of confidence level versus error. The concepts are illustrated with a simplified distribution system.