摘要：A brake-by-wire system is considered the best solution to realize advanced functions in electric vehicles/hybrid electric vehicles and intelligent vehicles. In this article, a novel electro-hydraulic brake system is proposed. The main issues in the development of the proposed electro-hydraulic brake system focus on hydraulic loop design and pressure tracking control. Instead of an accumulator, a large displacement piston pump coupled to a high-power motor is applied to meet the demand of pressure boost. A passive pedal feel simulator is designed to decouple the brake pedal and the wheel cylinders. The high pressure in the wheel cylinders is controlled by de/activating the motor and valves to track the reference pressure. To minimize the pressure instability observed in previous proportional–integral–derivative controller tests, a self-tuning generalized predictive controller is applied. Models of each system’s dynamic process are derived, and the parameters are identified through test data. A sliding mode differentiator is used to filter the sensor signals and improve the pressure boost performance in hard brake maneuvers. A rapid control prototype test environment based on dSPACE is built to verify and adjust the controller. The simulation results using MATLAB/Simulink and bench tests are presented and analyzed. Tracking performances show that compared to a proportional–integral–derivative controller, the proposed controller has a better effect in lowering pressure overshoots and start–stop frequency.
关键词：Electro-hydraulic braking system; system identification; Levant differentiator; generalized predictive control; rapid control prototype
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