Abstract

With more inverter based generations the nature of voltage variation during grid events changes requiring new approach to network voltage support. This paper develops an optimal control strategy for grid-forming inverter-based resources (GFM-IBRs) to provide the maximum dynamic voltage support (DVS) to the grid considering the current limitation and thus offering an effective Low Voltage Ride-Through (LVRT) capability. In this paper we look at different current limitation control methods that have been proposed in the literature. A new active current priority and reactive current priority, have been investigated and compared with the existing Optimal dynamic Voltage Support. The results suggest that prioritizing the fault current, does not always give the optimal support if X/R ratio is not taken in to consideration. Despite the IBR reaching its maximum current limit, oDVS (optimal-dynamic voltage support) has been found to be the optimal solution making the inverter provide maximum voltage support at the Point of Common Coupling (PCC) while keeping the phase angle at its optimal value.