CDFLOW: A Practical Tool for Tracing Stationary Behaviors of General Distribution Networks

The widespread use of distributed generations (DGs) in utility distribution feeders is a trend, and it brings about several challenges to the operation, planning, and design of general distribution networks. In this paper, a comprehensive tool, Continuation Distribution Power Flow (CDFLOW), is presented and evaluated. CDFLOW can be used for tracing steady-state stationary behaviors of general unbalanced distribution systems due to various types of power injection variations, including high penetration of DGs. The major computation engine behind CDFLOW is the continuation method. Major components, either balanced or unbalanced, grounded or ungrounded, are well modeled in CDFLOW. A detailed description of CDFLOW and its implementation regarding the predictor, corrector, adaptive step-size control and parameterizations are presented. For illustrative purposes, CDFLOW was applied to the IEEE 8500-node test system and a practical 1103-node distribution networks with promising results.