Design of adaptive continuous barrier function finite time stabilizer for TLP systems in floating offshore wind turbines

Abstract

This essay discusses the finite-time stabilization of Tension Leg Platforms (TLP), one of the most considerable offshore floating wind turbine systems. The most critical issue in installing such turbines is controlling and balancing them on the water. In order to stabilize the TLP systems in floating offshore wind turbines, an adaptive terminal sliding mode controller is designed. Because the discontinuous signal function is one of the most important disadvantages of common sliding mode controllers, which causes an undesirable chattering phenomenon in the control law, the suggested approach introduces a new Lyapunov candidate function based on the adaptive continuous barrier function technique, so that the planned control law on TLP systems is obtained continuously and smoothly. The mentioned improved control method uses Lyapunov's stability theory and satisfies the convergence of states around the switching surface in a finite time. In this way, the proposed method removes the chattering phenomenon and operates with higher accuracy than the conventional controllers. In addition, the unknown bound of external disturbance is estimated using the adaptive control scheme. Finally, based on the simulation results, it can be seen that all the state variables of the TLP system are asymptotically stable in the presence of external disturbance and converge to zero, which indicates the efficiency of the proposed technique for stabilizing the tension leg platforms in offshore floating wind turbines.