A robust adaptive modulation controller design based on backstepping for thyristor controlled series capacitor

Based on a nonlinear third-order model for a single-machine infinite-bus system with thyristor controlled series capacitor(TCSC), two kinds of nonlinear controller were designed using backstepping methods. With backstepping, the origin nonlinear system doesn't need to be linearized and the closed-loop error system is guaranteed to be asymptotically stable. When damping coefficients is measured inaccurately, a dynamic feedback controller can be designed using adaptive backstepping containing the real-time estimation of uncertainty parameter. The design procedure reveals that the controller designed by backstepping possesses good performances.