A Comparison of the Impact of Current Priority Modes of Inverter-Based Resources on the Performance of Grid Protective Relays

The dynamic response of inverter-based resources (IBRs) during fault-ride-though condition is driven by their control system, and it can be greatly different from that of synchronous generators (SGs). To standardize the fault response of IBRs, the recently published IEEE Std. 2800-2022 has defined two different current control modes during abnormal voltage conditions, i.e. reactive current priority mode and active current priority mode. This paper compares these control modes based on their impacts on the grid protective relays. To do so, the reference currents generator of IBR is designed so as to utilize the maximum current capability of the IBR while complying with the requirements of the mentioned standard. Followed by modeling an IBR with its complete closed-loop control system, simulation studies are carried out on a test power system in the PSCAD/EMTDC software. The obtained results indicate that the reactive current priority mode is superior for the correct operation of grid protective relays. Whereas, the active current priority mode may lead to malfunction of some conventional protective relays.