Assessment of Total Transfer Capability for simultaneous transactions in decentralized multi-areas power systems
With the liberalization of the electricity market, the cross-boarder transactions have become more common but set up new problems due to the non-existence of a global interconnected network operator which would have a whole knowledge of such electrical system. This article considers simultaneous transactions over multi-areas power systems, which are operated by different Transmission System Operators (TSOs), to assess a reliable value of Total Transfer Capability (TTC), in a decentralized manner. It is assumed that the TSOs have the will to cooperate each others, which leads us to use a decentralized power flow to get the Power Transfer Distribution Factors (PTDFs) for each area over the whole network. This approach also gives us the opportunity to review what are the shared information in a multi-areas power system. A simple model of the information exchanged between neighboring areas is provided to shows out it is a key point for running the decentralized algorithm. In the same time, the concept of simultaneous TTC is introduced. Then, each TSO uses the right PTDFs corresponding to its own area and computes the multiple TTC's by solving an integrated Linear Programming problem. These values are then used to assess the ultimate multiple TTC's using an appropriate cooperation among adjacent areas. The numerical results for a four-area test system demonstrates the performance of the proposed model.