Unbalanced Power Flow Calculation in Active Distribution Networks Based on Improved Sequence Components

Abstract

Phase components approach is not suitable for parallel computing of fast simulation in active distribution networks(ADN). A improved sequence components method is proposed. It can be efficiently applied to parallel computing of three-phase power flow in ADN. Firstly, the paper builds sequence components models of ADN components based on compensation method. And adds virtual line to simplify sequence components of the open phase that have been difficult to handle in distribution networks, it can build unified sequence components models for entire distribution networks line. Secondly, unbalanced distribution networks is decomposed into three sequence networks and compensation parts. Positive sequence power flow are the same as those used by any single phase power flow algorithm, the negative sequence and zero sequence networks are calculated by nodal voltage equations. Parallel computing can be used for three decoupled networks to achieve higher computational speed. Finally, the simulation results of test examples are provided to demonstrate the correctness and effectiveness of the proposed method.