An adaptive control system via a Riccati equation and its application to power systems

The dynamics of power systems contain the nonlinearities such as trigonometric functions and the parameter uncertainties of reactances of transmission lines caused by short circuit faults. Wang et al. proposed an adaptive nonlinear controller for a single generator connected through two parallel transmission lines to an infinite bus. They employed the feedback linearization technique and the linear adaptive control technique. Though they used the power angle, the relative speed of the generator and the active electrical power as feedback signals, the power angle is not usually available. So, we design an adaptive nonlinear controller without the power angle feedback-path for Wang´s power systems model. We employ the adaptive control method with a Riccati equation in designing the power system stabilizer