Line independency-based network modelling for backward/forward load flow analysis of electrical power distribution systems

Abstract

In this paper a straightforward method for line independency-based modelling of electrical power distributionsystems is proposed. The proposed method can determine the backward and forward sweeping routes of distributionsystems for calculating line currents and bus voltages. To do that, the method identifies the independent lines inconsecutive steps. An independent line is a line in the distribution system whose current does not depend on the currentof other lines in the system. The proposed line independency-based network modelling is required to be performed onlyonce and prior to the load flow analysis. The output of the proposed method, which is suitable for backward/forwardload flow analysis, includes matrices which determine the steps, the order of lines, and the start and end points in thesystem for hierarchical calculation of currents and voltages. In this paper, the forward/backward approach is used as theload-flow algorithm since it is suitable for radial distribution systems with unbalanced loads. The proposed methodologyis applied on two IEEE distribution systems and the results show its efficiency in load flow analysis.