Hydraulic anti-lock braking control using the hybrid sliding-mode pulse width modulation pressure control method

This study integrates the discrete on-off operation of hydraulic high-speed solenoid valves and the pulse width modulation (PWM) method to achieve a quasi-continuous braking pressure control. Sliding-mode control is applied here due to the non-linear nature of the solenoid valve. The hybrid compensating method presented here compensates for the mechanical and electrical delay of solenoid valves, obtaining more precise control results and keeping the robustness of the sliding controller. Following verification of the braking pressure controller on a test stand, an anti-lock braking controller of a passenger car is designed by use of tyre tangential deceleration feedback. This anti-lock braking controller is also verified on a dynamic test stand. Braking experiments on both dry and wet road surfaces are simulated.