Adaptive Active Damper for Improving the Stability of Grid-Connected Inverters: Review

A weak grid might cause instability in a system that uses a grid-connected inverter. The point of common coupling (PCC) can be coupled to an adaptive active damper, which will automatically adjust a virtual resistor to the critical value in order to stabilise the system. Additionally, a harmonic current reference compensation approach is employed to control the virtual resistor simulation throughout a broad frequency range. This study presents the use of the harmonic current reference compensation approach for the three phase adaptive active damper controlled by the decoupled synchronous d-q frame, synchronous α−β frame, and stationary α−β frame. This technique allows the adaptive active damper to directly regulate both reactive and active power while simultaneously enhancing the stability of the grid-connected inverters in the event of a weak grid.