Transient stability enhancement of power systems via optimal nonlinear state feedback control

In this paper, the transient stabilization of power systems will be enhanced using optimal nonlinear feedback control. To this end, a partial differential equation called Hamilton-Jacobi-Belman (HJB), should be solved, which does not have a closed form solution in general. Nevertheless, there are some approximate solutions to solve HJB equations. In this paper, by using a Taylor Series expansion, a sub-optimal nonlinear control law is obtained. As a result, a transient controller for a single-machine infinite-bus power system is designed. Also, the superiority of the designed nonlinear controller in some grounds like increasing the region of asymptotic stability of the system or in other words, increasing the domain of validity is shown. Simulation results reveal the effectiveness of the proposed approach.