The widespread diffusion of generation units powered by renewable sources is strongly impacting the electricity grid from various points of view. One of the aspects to consider is linked to the reduction of the overall system inertia resulting from the replacement of large systems connected to the grid by synchronous machines with small systems connected by power converters.
The study of new power converter control algorithms and related stability properties is a highly debated topic: the discussion aims to counter this phenomenon and ensure safe and reliable operation of the entire system.
From the analysis of the literature it is evident that the performances of the classic droop control and Virtual Synchronous Machine Control (VSMC) approaches are largely improved by new ones, such as those of Matching Control (MC) and dispatchable Virtual Oscillator Control (dVOC). Under some conditions, these techniques guarantee global stability properties and are, in general, more suitable for formal analyzes for the demonstration of their properties.
The purpose of this activity is to assess the dynamic performance of the control algorithms of the inverters that interface distributed generation to the grid in a simulated environment, focusing on their ability to guarantee operational stability in the event of small or large contingencies. The assessments were conducted considering the performance of the network in the case of co-existence of inverter-based generation and generation based on synchronous machines and in the case of multiple converters regulated with heterogeneous control techniques. The outcomes show that in the case of a network with low inertia the analyzed controls improve the network stability.