Robust and Low Order Power Oscillation Damper Design Through Polynomial Control

The paper presents a method for designing low order robust controllers for stabilizing power system oscillations. The method uses polynomial control techniques. For single-input/single-output systems (SISO), the variability in operating conditions is captured using an interval polynomial. Kharitonov´s theorem is then used to characterize a fixed order robust controller guaranteeing specified damping. This gives bi-linear matrix inequality (BMI) stability conditions which are solved using the BMI solver PENBMI. The effectiveness of the method is demonstrated by designing power oscillation damping (POD) controllers for single-, four-, and 16-machine power system models.