Effect of high penetrated reactive power support based Inverter-Based-Resources on the power stability of microgrid distribution system during faults.

As the penetration level of inverter-based resources (IBRs) in a distribution system has been increasing, the development of the IBRs control scheme becomes mandatory, mainly to make the distribution systems more resilient to the disturbance. Most of the IBRs that have been integrated into the distributed systems operate in power factor correction mode. This control scheme focus on optimizing their electricity production. Given this context, this control scheme might deteriorate the fault-ride through (FRT) capabilities during and after the fault. In a bigger picture, this might cause the system to collapse when the IBRs penetration is getting higher. This paper proposes a novel control scheme of a photovoltaic (PV) power plant with enhanced FRT and fault restoration capabilities. To achieve this, the reactive current is injected into the system whenever it senses a fault. After the fault being cleared, the operation of control scheme changes to provide reactive power support to the system. The proposed method is verified using IEEE 13-bus system, which simulated using PSCAD simulator. The results show that the inclusion of the proposed scheme in a PV power plant would help the system to secure its resiliency for a severe network fault by supporting voltage stability during the fault and post fault condition.