Comparison of Transmission Technologies with Regard to their Contribution to Power System Stability

Abstract

The amount of power to be transmitted is increasing worldwide. Hence, a considerable number of bulk power transmission projects are going to be realized (e.g. [1]). Taking into account the recent technical development, three technologies are available for bulk power transmission: Direct current applications with voltage sourced or line commutated converters as well as the high-voltage AC technology up to 1200 kV. To select the most suitable technology for a particular project is often anything but trivial for the transmission system operator. Amongst other criteria, the influence on the electromechanical behavior of the power system is a decisive factor for network improvements that should be considered within the decision-making process. This paper aims at categorizing and analyzing this rather abstract term as a major criterion. The goal is to provide an indication, which factors are needed to be evaluated in advance of the well-considered choice. For that reason, several categories are introduced and thoroughly investigated within the scope of a theoretical approach. Where reasonable, simulation results are presented in order to enable the practical assessment of the impact on the electromechanical system behavior. As a conclusion, it is recommended to perform concise ex-ante studies with regard to the electromechanical dynamics as a decision-making basis to identify the most suitable transmission technology for a particular project.