Design of a robust iterative PID controller for power system stabilizer using h2-norm

Abstract EN

In steady-state, the speed deviation of the generators in the power systems is zero or closely zero by the action of the Automatic Voltage Regulator (AVR).

However, in transient-state, the rotor swings and the terminal voltage undergoes oscillations caused by the change in rotor angle.

The Power System Stabilizer (PSS) is usually added in conjunction with the AVR to help damping such oscillations by adding an additional signal that compensates for the voltage oscillations.

The rotor speed is commonly fed as input to the PSS whereas its output is added as a signal to the AVR.

It is a cost- effective method for enhancing stability in any power system.

A lot of types of PSS structure were proposed in the literature.

In this paper, H2-norm is used to design iteratively a PID via LMI technique.

Its effectiveness is shown through a comparison with two types : the first is the conventional lead-lag controller, designed with Genetic Algorithm, and the last is an HS-norm LMI-based robust output feedback controller.

Several tests were carried out namely, regulation and tracking of the terminal voltage and mechanical torque to their respective references, and a wide parameter variation.

The results show the superiority of H2-PID to damp the power system oscillations.