A toy model to understand subsynchronous resonance and real-time simulation of the model using RTAI-Linux

This paper presents a toy- model to demonstrate the concepts of torsional interactions that occur during the subsynchronous resonance (SSR) problem in power systems.The content of the paper evolves as a tutorial and motivates a novice to take up SSR studies on relatively complex systems such as the IEEE first and second benchmark systems which contain many intricate modal interactions. To show the utility of the model and to impart a realistic touch in the lab environment the complete system is simulated in real-time using real-time application interface (RTAI)-enabled Linux platform. Using a peripheral component interconnect (PCI) card, the real-time simulation results are captured on an oscilloscope and are validated using off-line MATLAB simulations.