Small-signal Stability Analysis of Power Systems with Inclusion of Periodic Time-Varying Delays

The paper presents a systematic numerical approach to estimate the small-signal stability of power systems with inclusion of periodic time-varying delays. With this aim, the paper first provides the mathematical background of the proposed approach and then discusses the numerical implementation of three types of periodic delays, namely, sinusoidal, sawtooth and square wave. The case study is based on the IEEE 14-bus system with inclusion of a power system stabilizer, whose input signal is assumed to be obtained through a wide-area measurements system. Small-signal stability analysis and time-domain simulation following a large disturbance of the system are presented and discussed.