Damping coefficient compensation of generator by novel nonlinear excitation control

In this paper, a novel nonlinear excitation control scheme has been proposed based on transient energy function and backstepping design method, which can not only compensate the damping coefficient of generator directly, but also guarantee asymptotical stability of the designed control system. For a SMIB (single-machine-infinite-bus) system, from the view of adding damping and enhancing system stability, an extra damping term is introduced into the motion equation, and then the designed system can be viewed as a series of two dynamic equation sets. Based on backstepping method, a transient energy function is constructed and the corresponding nonlinear excitation control law is deduced. In this control law, only two parameters are chosen, i.e. the expected damping coefficient increment and the expected voltage feedback gain. Executable approximations of the controller are also discussed. Simulation results confirm the validity of the controller and show that it is efficient when system operating condition changes