Robust Control of Terminal Voltage of an Isolated Electric Power Generating Unit

The performance of an automatic voltage regulator (AVR) system controlled by an optimal linear-quadratic-Gaussian (LQG) controller augmented with an integral action is investigated in this article for maintaining constant output voltage. The aim of this controller is to keep stable terminal voltage of a power system during sudden load variation. To verify its efficacy, a comparison is conducted with some existing controllers for instance the rate feedback stabilizer, proportional-integral-derivative (PID) controller, and linear quadratic regulator (LQR). The comparison is done on the basis of some important transient response characteristics and the proposed control scheme shows strong robustness against voltage variation due to load change.