A DISTRIBUTED POWER FLOW CALCULATION FOR AC/DC INTERCONNECTED SYSTEM BASED ON ASYNCHRONOUS ITERATION

摘要

The contradiction between AC/DC interconnected power grid and the independent calculation mode adopted by regional control centers brings in various drawbacks to the analysis and monitoring of power network. To solve these questions, a distributed power flow algorithm for AC/DC interconnected power grid is proposed, which is based on asynchronous iteration mode. The algorithm is suitable for two-terminal HVDC transmission system as tie-lines which are modeled at two subsystems. Sequential method for AC/DC power flow calculation is as interior iteration. During the exterior iteration, DC system is equivalent to AC line which is used to construct fix point iteration about boundary state variable; equivalent injection power on the boundary buses is modified gradually in order to obtain a power flow result consistent with that for whole system. The experimental results of IEEE standard systems and the real-life interconnected system which are extended to AC/DC power system indicate that the algorithm is accurate.