The use of renewable energy sources has been increasing during the last few years, both to obtain a less impacting energy production, and because of the limited fossil resources. Renewable sources are connected to the grid using inverters, which can be controlled in two main modes, grid-following, and grid-forming. Grid-following inverters (GFLIs) operate connected and synchronized to the grid. GFLIs can be considered as current sources, which adjust their output current to obtain a certain power. Because GFLIs cannot form the grid voltage, they cannot operate in standalone mode. On the other hand, grid-forming inverters (GFMIs) are controlled to form their output voltage by setting the voltage amplitude and frequency.