重型拖拉机电液悬挂比例控制器设计

Proportional Controller for Electro-hydraulic Hitch System in Heavy Tractor

设计了一种基于飞思卡尔MC9S12XS128型微处理器的电液悬挂比例控制器。根据重型拖拉机电液悬挂系统控制要求,在分析现有重型拖拉机电液悬挂比例控制器的结构、类型和特点的基础上,确定了比例控制器的整体设计方案,在Code Warrior环境下完成软件程序设计,采用PID控制算法实现对拖拉机作业机组的位控制、牵引力控制和力位综合控制。以重型拖拉机电液悬挂系统为试验平台,对所设计的电液悬挂比例控制器进行了田间试验,牵引力和耕深控制的过渡时间分别为3.89 s和0.81 s。结果表明:比例控制器对重型拖拉机悬挂装置的综合控制具有响应快、精度高、稳定性强等特点,在保证拖拉机平顺性和作业质量的同时,提高了作业效率,降低了拖拉机驾驶员的劳动强度。

A proportional controller for the electro-hydraulic hitch system was developed based on the microprocessor MC9S12XS128 of Freescale. According to the analysis of the structure, type and characteristic of present proportional controllers for the hitch system,the controller architecture was put forward following the control requirements. The software was designed in the environment of Code Warrior,and the PID control algorithm was adopted to realize three control modes including traction,position and mixed control for hitch system. By taking the heavy tractor with electro-hydraulic hitch system as the test platform,the field experiment of the proposed proportional controller was carried out,the response time of traction control was 3. 89 s while 0. 81 s of position control. The results showed that the proportional controller for hitch system comprehensive control in high-power tractor possessed of the features of rapid response,high precision,strong stability,etc. Meanwhile,it can not only improve the field operating efficiency in the guarantee of ride comfort and working quality of tractor,but also can reduce the driver's labor intensity.