A New Virtual Synchronous Generator-Based Power Control Method for Enhancing the Frequency Stability Contribution of Grid-Forming Inverters

As the penetration of renewable energy sources increases and the inertia of the power system decreases, frequency instability in the grid is a possibility. Furthermore, power electronic converters can induce various resonance instabilities in the power grid. Recently, research on grid-forming inverters, which emulate the dynamic characteristics of synchronous generators and provide inertia and damping to the power system, is actively being conducted. This paper conducts modeling of a grid-forming inverter for resonance stability analysis and controller design and proposes a novel control strategy that not only emulates the characteristics of synchronous generators but also improves the frequency nadir through faster primary frequency response compared with conventional grid-forming inverters by combining PI and IP controller.