In the last years, the generation of energy by renewable sources has experienced a significant push. At the same time, the consumer loads have been increasing on a daily basis (electric vehicles and heat pump). The increasing of both generation and demand have an important impact onto the power quality grid, which in turn has various effects, such as harmonics, voltage variations, overloading components, bidirectional power flow and so on. One possible solution to mitigate these effects would be to replace the AC lines in some parts of the grid by a flexible AC-DC line (FLINK). It consists of connecting different AC grids by a flexible link, which can operate in AC or DC via Power electronic elements (two converters, a rectifier and an inverter). As we will see further, switching from AC to DC may provide different benefits so as to maintain balance in the grid. It would be important to know when it is better to use either type of connection and at which point we should shift. Another goal would be to successfully implement this system, as simplified as possible, so that a distribution network operator may be able to handle it. The main goal on the project has been to give support to the research conducted in the Smart Grid Lab at TU/e by a team from the Department of EES. The research consisted on the study of the interactions between two independent electrical networks connected to each other at one point by the FLINK. In order to study the behaviour of the FLINK when operating in AC or DC mode, different unbalance conditions have been set for each network, evaluating then the FLINK efficiency to isolate both networks against ancillary services (voltage dips, harmonics…), while enabling only a stable transmission of active power. In addition, another aim has been to demonstrate the fact that when FLINK operates in AC there is a larger capacity gain than when it does in DC. My personal addition to the experiment could be summed up with the following points: an appropriate comprehension of the FLINK research (project scope, design or operational aspects and practical applicability); a study of each and every device used in the experiment in a controlled environment, setting operating conditions for the tests; preparation of the experiment physical layout in the laboratory by both following the team’s specifications and finding ways to improve; assistance in the actual experiment, by configuring and running device monitoring and recording data collected by power analysers; discussion of the obtained results and contributing with my own thoughts to future research and laboratory upgrades. This report collects the main aspects of the experiment preparation: First, explanation of FLINK fundamentals, operation modes and its practical applicability (specially in the Dutch Network); then, detailing pre-existing work, analysing the functionality for each device and proposing conditions for the tests; next, description of the experiment and tested conditions; discussion of results; And finally, conclusions from the obtained data and thoughts for future experiments.
