A development of a single-phase synchronous inverter for grid resilience and stabilization

This paper provides a control methodology for a single-phase synchronous inverter which enables the inverter to implement dynamic characteristic of synchronous machines directly. As one of solutions for the power system instability due to penetration of renewable energy sources, a concept of virtual inertia has been proposed. Many previous researches on this field employed the voltage and current feedback controller to realize ideal behavior based on theoretical mass model of synchronous machines. However, a controller including the multiple feedback loops has difficulty in optimizing control parameters. The non-optimized controller with lead or lag at frequency of the rotational mass cannot achieve the designed dynamic characteristic. We develop a controller that realizes direct implementation of a swing equation as well as protection of the inverter from the overcurrent. The numerical simulation demonstrates that the proposed controller does not disturb the dynamic characteristic of the synchronous inverter and enhances the grid stability.