Riquelme Domínguez, José MiguelGonzalez-Longatt, FranciscoSilva Melo, André FelipeRueda, José LuisPalensky, Peter2025-01-222025-01-222024-03Riquelme-Domínguez, J.M., Gonzalez-Longatt, F., Silva Melo, A.F., Rueda, J.L. y Palensky, P. (2024). Cyber-Physical Testbed Co-Simulation Real-Time: Normal and Abnormal System Frequency Response. IEEE Transactions on Industry Applications, 60 (2), 2643-2652. https://doi.org/10.1109/TIA.2023.3342764.0093-99941939-9367https://hdl.handle.net/11441/167242©2023 The Authors. This work is licensed under a Creative Commons Attribution 4.0 License.Future carbon-neutral power systems impose many challenges; one is the urgent need for a simulation platform that allows replicating the complex systems' actual dynamic performance. This paper shows the results of implementing a cyber-physical testbed co-simulation in real-time to analyse the system frequency response considering primary frequency control and emergency frequency control: under-frequency load-shedding (UFLS) protection schemes. The proposed testbed uses a physical layer of two real-time simulators from different vendors in a closed loop, Opal-RT OP4510 and Typhoon HIL 604, being the first simulator for test system modelling and the remainder used to implement the UFLS protection scheme. Two connections of the real-time simulators are considered: physical connection using wires to exchange analogue signals and cybernetic digital communication using ANSI C37.118 communication protocol. The cybernetic layer of the testbed models a test system, controls the real-time simulation, and implements digital communication between the simulators. A modified version of the P.M. Anderson 9-bus systems is used for testing purposes, including phasor measurement units (PMUs). Results of the real-time simulation show the appropriate performance of the proposed testbed.application/pdf10 p.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/ANSI C37.118Co-simulationhardware-in-the-looplow inertia power systemsreal-timesystem frequency responseinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccesshttps://doi.org/10.1109/TIA.2023.3342764