Feature analysis of power flows based on the allocations of phase shifting transformers

Summary form only given. This paper proposes a novel approach to identify the deviations of power flows, which are controlled by multiple phase shifting transformers (PSTs). In order to control the power flows of each loop independently, at the first, the minimum need of PST sets is determined as the number of co-tree to the entire network. For the reason of the co-tree patterns are not unique, there are many PSTs allocations existing and can be found as the co-tree patterns. Continuously, characterizing the sensitivity of power flow deviations to PSTs control angles into a matrix. By which, the features of the controllable area of power flows corresponding to all PSTs allocation candidates can be extracted by the eigenanalysis of the matrix. Finally, judging from the power flow profiles, the optimal allocation to the specific control target can be found. From the viewpoint of the flexible power flow control in an open access network, it is contributed to find out the optimal PSTs allocation for power flow control. The effectiveness of the proposed method is confirmed by the simulation studies of two model systems.