A Classification of Grid-Forming Converter Control and its Application to Improve Power System Stability and Resilience

Over the last decade, different methods of grid-forming control have been formulated, all aiming to emulate the basic behavior of synchronous generators. Comparative studies show that some of these methods have similar or even identical characteristics if parameterized in an adequate way. Focusing on the power control loop, one important difference is whether the grid-forming control will react to disturbances in the grid frequency and voltage amplitude based on the rate of change or based on the deviation from nominal. In terms of active power control, this correlates to the inverter contributing only to inertia, only to the frequency containment reserve or both. This article provides a comparison and classification of existing grid-forming control methods and illustrates the application in a simulative case study and experimental field test.