Summary
The functioning of communication and control networks inevitably impacts the reliability of power systems. However, due to the complex cyber‐power interdependencies and the unavailability of a benchmark testbed, developing feasible and effective models that incorporate the impact of cyber system failures on power systems is challenging in reliability studies. In this paper, we propose the framework of a benchmark testbed by extending the IEEE Reliability Test System (RTS) 79 with cyber configurations. A comprehensive methodology to model intra and inter substation malfunctions is also presented to quantitatively compute the impact of cyber failures on composite power system reliability. System‐wide reliability indices, such as the loss of load expectation and the expected energy not supplied, are obtained. Simulation results demonstrate that power system reliability is degraded due to cyber malfunctions. Furthermore, the extension of the IEEE RTS 79 with information and communication technology specifications provides a benchmark tool for researchers in future cyber‐physical reliability studies.