Phase Shifting Transformer Application with Considering the Economic and Reliable Operation of the Grid

It is widely accepted that the Flexible AC Transmission Systems (FACTS) such as phase shifting transformer (PST) can be a long-term solution in order to address the transmission congestion. In order to guarantee the good performance of the PSTs, this paper proposes a new two-stage methodology to find the optimal locations for PSTs. In the first stage, some candidate locations are selected aiming to minimize the overall system operation cost and investment costs considering N-1 contingency security criterion. In the second stage, the multi-attribute decision making (MADM) technique has been devised to evaluate and then rank the candidate locations based on some important system performance indices. The speculated indices suitably represent the power system security and reliability, transmission congestion, and power transfer capability. The outcome is the best locations to site the PSTs with regards to both technical and economic aspects.