Impact of saturation nonlinearities/disturbances on the small-signal stability of power systems: An analytical approach

In this paper, a multi-objective optimization model is presented to estimate the practical stability region and maximum endurable disturbance rejection for a small-signal power system dynamic model with saturation nonlinearities and disturbance rejection. Iterative algorithms are developed to solve for Pareto optimized solutions (POS) of this optimization. Furthermore, as an application of this approach to power systems, a method to analyze the impact of saturation nonlinearities and disturbance rejection on power system small-signal stability is introduced based on the estimated stability region and maximum endurable disturbance rejection. Numerical results of a test power system with detailed saturated PSS controllers are described, indicating the reliability and simplicity of the method.