Towards Grid Code Compliance Testing at Real-Time Speeds: A Workflow to Migrate OEM Black-Box Controller Models from Offline to Real-Time

The rapid integration of inverter-based resources (IBRs) is increasing the demand for grid code compliance with emerging standards such as IEEE 2800. However, many original equipment manufacturers (OEMs)-supplied IBR controller models remain limited to offline electromagnetic transient (EMT) simulation environments as black-box models, where slow runtimes make real-time applications such as controller hardware-in-the-loop testing impractical. This limits the ability of renewable developers and system operators to perform repeatable, standards-based validation. To address the issues, this paper presents a streamlined workflow for migrating black-box controllers to real-time simulation using a standardized interface architecture, based on the IEEE–CIGRÉ B4.82 joint working group’s technical guidelines. This interface preserves OEM’s intellectual property (IP) while supporting platform interoperability. The workflow also includes automated migration of the power circuits, preparation for execution of the models in real-time, and an automated IEEE 2800-based test suite to accelerate compliance efforts. Simulation results demonstrate strong alignment with offline models while achieving a 2× reduction in simulation time. Our approach enables full real-time execution of the IEEE 2800 test suite and supports scalable software- and controller-in-the-loop testing, ensuring grid code compliance validation for OEM controllers while maintaining fidelity comparable to offline EMT simulations. This method enables pre-installation hardware-in-the-loop testing of protective relays, grid support devices, and other hardware to identify performance issues, adverse interactions before deployment.