Improved Grid-Connected Inverter Control for Enhanced Protection in Distribution Systems with High Penetration of Inverter-Based Resources

This paper addresses the challenges faced by protection systems in modern distribution networks with a significant presence of inverter-based resources (IBRs). It proposes an adaptable current-limiting control strategy for grid-following (GFL) inverters that incorporates dynamic voltage support for positive as well as negative sequence components. The control scheme ensures sufficient current contributions during symmetrical and also asymmetrical faults, enabling reliable operation of protection relays. The proposed method was evaluated on a modified IEEE 123-node test feeder. Results demonstrate the control strategy's ability to improve the reliability of protection relays under varying fault conditions, facilitating seamless integration of IBRs in distribution systems.