An improved method of damping of generator oscillations

An improved method of damping of generator oscillations under large disturbances resulting from large hydraulic transients is presented in this paper. The digital controller, which consists of both governor and exciter controllers, is used. The controller operates in real time to improve the generating unit transients through the exciter input, the guide vane position and the runner blade position. The developed digital controller, whose control signals are adjusted using the on-line measurements, offers better damping effects for the generator oscillations under large disturbances than the conventional controller does. Digital simulations of hydroelectric power plant equipped with low-head Kaplan turbine are performed and the comparisons between the digital control and the conventional control are presented. Simulation results show that the improved controller offers better performances than the conventional controllers and the digital governor controller, when the system is subjected to large disturbances.