一体式电液复合制动系统轮缸压力的精细调节

Wheel cylinder pressure fine regulation for integrated electro-hydraulic brake system

针对基于一体式主缸的电液复合制动系统,进行了轮缸压力的精细调节研究,分析了一体式复合制动系统轮缸压力调节过程及其结构特点.探讨了制动间隙对盘式制动器轮缸压力调节的影响,确定了轮缸压力控制的非线性区及线性区,采用阶梯估算和基本插值数表的方法对轮缸压力进行估计,并考虑了线性区轮缸活塞运动迟滞特性对插值数表的影响,综合上述因素制定了分段阶梯查表的轮缸压力精细调节策略.采用xPC target搭建了硬件在环仿真台架,进行了正弦曲线跟随和与单一增/减压数表法的对比试验.试验结果表明:轮缸压力能够实时跟随目标曲线变化,所提出的结构及控制方法能够满足轮缸压力精细调节的控制需求.

Wheel cylinder pressure fine regulation was studied for electro-hydraulic brake system with an integrated master cylinder.Pressure regulation process and system structural characteristics were analyzed.The impact of brake disc gap on pressure regulation was studied,pressure control dividing point of non-linear and linear region was determined,using the ladder method and interpolation table method to estimate cylinder pressure,also the impact of wheel cylinder piston hysteresis characteristics on linear region was considered,and then the segmented-ladder-lookup fine regulation strategy was developed.Hardware in the loop simulation bench was built using xPC target to verify the pressure regulation performance by sine target pressure test and comparisons of single increase-decrease interpolation table strategy and the proposed one.Test results show that the wheel cylinder pressure could keep up with the target curve,and the proposed system structure and pressure regulation method could meet the pressure control requirements.