Adaptive friction compensation for large diameter electro-hydraulic proportional valve cores based on LuGre

This paper presents an adaptive friction compensation method based on LuGre model for large diameter electric-hydraulic proportional valves in which the valve core contains friction. A mathematic model of the electric-hydraulic proportional valve is established, and the friction characteristics are described based on the LuGre model. The global asymptotic stability of the control system with the adaptive friction compensation controller is guaranteed over Lyapunov theorem. The adaptive compensation of the friction on LuGre friction model is verified by simulation and experiment. The steady-state error is about [-4.23×10-5 m, 5.91×10-5 m] and [-2.5×10-4 m, 2.6×10-4 m] on simulation and experiment, the position tracking accuracy is higher, and the lag time of the main valve through the dead zone is shorter. The result proves that the adaptive friction compensation method can effectively compensate for the negative effects of nonlinear friction. Copyright © by HIGH TECHNOLOGY LETTERS PRESS.