Abstract: The analog signal of the brake pedal has a direct influence on the normal realization of the regenerative braking energy function and the service braking function of electric vehicles. Due to influence of factors as assembly consistency, driving stress alternation and road vibrations etc., the length of the brake pedal ejector pin changes, causing the ejector pin’s stroke to change, resulting in an unusual figure in the brake pedal analog signal value. This paper explains the reasons for the drift of the brake pedal analog signal for electric vehicles from two aspects of mechanical structure and electrical connection. That is, by accurately adjusting the fixed position of the top rod nut, the analog signal value of the brake pedal is always greater than 330; Changing the numerical range of the analog signal value of the vehicle controller is within this range. The study solves the problem of the electric vehicles brake pedal analog signal drift by changing the program of the vehicle control units.

Key words: Pure electric vehicles; Brake pedal; Signal drift; Brake pedal ejector stroke; Ejector nut

摘要： 制动踏板模拟信号对纯电动汽车制动能量回收功能及行车制动功能的正常实现具有直 接影响。由于车辆在行驶过程中受装配一致性、运行交变负荷、道路震动等因素影响，制动 踏板顶杆的长度会发生变化，从而引起制动踏板顶杆行程变化，导致制动踏板模拟信号数值 异常。结合某纯电动汽车制动踏板信号漂移现象展开研究，从机械结构和电气连接两个方面 阐述了导致制动踏板模拟信号漂移的原因和两种基本解决措施，即通过精确调整顶杆螺母固 定位置，从而改变制动踏板顶杆行程的方式，使得制动踏板模拟信号数值始终处于大于 330 的状态；更改整车控制器制动踏板模拟信号数值范围，使得制动踏板模拟信号数值处于该范 围之内。该研究解决了纯电动车辆制动踏板模拟信号漂移问题，为同类结构车辆制动踏板信 号漂移问题的解决提供了参考。

关键词: 纯电动汽车；制动踏板；信号漂移；制动踏板顶杆行程；顶杆螺母