Impact of external elements on the responsibility area of a Transmission System Operator using the influence factor method

In the last years, the electric power systems have been restructured, moving from a vertical integrated model to a market oriented environment. The new paradigms associated with the restructuring of the electricity sector made it critical to develop new efficient and reliable methodologies to study and analyze the security of the power networks. In this paper it is proposed a method to evaluate the impact of external elements on the responsibility area of a Transmission System Operator (TSO) using the influence factor method. This approach offers a concrete support in the determination of the observability area, which at the end remains in the responsibility of the single TSO. The influence factor is a numerical value used to quantify the greatest effect of the outage of an external network component on any internal network branch. The developed methodology was applied to study the IEEE 118 bus test power network. All simulations of the transmission systems of the IEEE 118 bus were performed using the PSS®E software package from Siemens PTI, making the division of the network in two countries (areas). From the simulation results, some conclusions that provide a valuable contribution to understanding the influence factor method are pointed out.