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arXiv · 2302.09931

An algorithm for DC segmentation of AC power systems to mitigate electromechanical oscillations

Abstract

In the last decades, various events have shown that electromechanical oscillations are a major concern for large interconnected Alternative Current (AC) power systems. DC segmentation - a method that consist in turning large AC grids into a set of asynchronous AC clusters linked by Direct Current (DC) links - is a promising solution to mitigate this and other issues. However, no systematic segmentation procedure for a given AC power system exists so far. This paper aims at filling this gap and proposes an algorithm for DC segmentation for a given AC power system to mitigate electromechanical oscillations. In this proposal, DC segmentation is implemented with High Voltage Direct Current links based on Voltage Source Converters (VSC-HVDC). The algorithm uses small-signal stability techniques and the concept of dominant inter-area oscillation paths to stop the main inter-area mode of the power system. The algorithm will be explained using a six-generator test system and it will then be used on the Nordic 44 test system. The proposed algorithm for DC segmentation has been validated by means of non-linear time-domain simulation and small-signal stability analysis (SSSA).

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Mathieu Robin, Javier Renedo, Juan Carlos Gonzalez-Torres, Aurelio Garcia-Cerrada, Abdelkrim Benchaib, Pablo Garcia-Gonzalez. 2023-02-20. An algorithm for DC segmentation of AC power systems to mitigate electromechanical oscillations. https://arxiv.org/abs/2302.09931

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