A two-phase power attracting law based discrete-time control

In this paper, a novel two-phase power attracting law based control scheme is proposed for a class of uncertain discrete-time systems. In the design of the attracting law, the convergence process of the tracking error is divided into two different stages, such that the amplitude of each convergence step and the error convergence speed can be both improved. An extend state observer is constructed to effectively compensate for system disturbances, and a discrete-time controller with two-phase power is presented to improve the system robustness and reduce the steady-state error. In addition, the steady-state error band, the attractive layer and the maximum step size of the tracking error converging into the steady-state error band are respectively derived to characterize both the steady-state and transient performance. Finally, simulation results show effectiveness of the proposed scheme. Copyright ©2022 Control and Decision.