Inertial Response of the Grid-Forming Converter Testing and Validation with the IPLL based Inertial Grid Source

The vast integration of renewable energy systems around the globe has raised some concerns over the loss of inertial support in the grid and its impact on the general grid stability. The penetration of renewable technology based on grid-following inverters in addition to the decrease of conventional generation is leading to a scenario in which the support from renewable energy resources is going to play a vital role in ensuring the stable operation of the whole electrical system. Inertia emulation has been one of the main topics during the last decade, where different approaches have been published throughout the years. However, in order to test that the desired amount of inertia is being provided from the grid-forming converter to the grid, specific parametrization has to be considered. This paper focuses on the implementation of an inertial grid source with adjustable mechanical and electrical parameters, making it capable of providing different grid scenarios for the unit under test. This implementation based on the so-called IPLL is presented, analyzed and validated in a real-time simulation environment.