LADRC of Bridge Crane System Based on Dead Zone Compensation

Abstract

This paper proposes a composite control scheme based on linear active disturbance rejection control (LADRC) and dead zone compensation technique to solve the problem of dead zone behavior and reduce sensitivity to disturbance in industrial bridge crane control systems. The poor control performance caused by dead zone problem in bridge crane system is addressed by constructing a smooth inverse function to approach its inverse so as to remove its bad influences. An extended state observer is developed to estimate the “lumped disturbance” caused by parameters perturbations, external disturbances and unmodeled dynamics in real time, and a linear control law is proposed to attenuate the disturbance and achieve angle and position control based on LADRC. Both simulation and experiment results show that the proposed method not only can compensate the adverse influences caused by dead zone, but also have better steady-state accuracy and anti-disturbance performance.