液压轮毂马达辅助驱动系统控制策略实车验证

Verification of control strategy of hydraulic hub-motor auxiliary system on actual vehicle

摘要:

为充分提升重型牵引车辆通过不良路面的能力,对国内某款重型牵引车在传统结构的基础上加装了前轴液压轮毂马达辅助驱动系统,并针对该混合动力系统,开发了工程化的控制策略,实现分时全驱控制. 该策略通过对两套动力系统的工作状态和驾驶意图的识别保证系统模式的平稳切换,控制液压系统适时介入与退出,在各模式下对泵排量进行合理的控制,助力模式下实现轮速良好跟随. 采用该控制策略的实车试验结果表明:驾驶员操作意图识别准确,模式切换和换挡平顺性好；两系统工作协调且互不干扰,行驶安全性得以保证；各模式下变量泵排量响应合理,轮速跟随方法有效. 实车试验验证了轮毂液压混合动力系统实际应用的可行性和所提策略的合理性.

Abstract:

To improve the pass ability of heavy-duty tractors, a hydraulic hybrid heavy-duty tractor is equipped with a hydraulic hub motor auxiliary drive system on front axle based on the traditional structure. On this basis, an engineering control strategy is developed to achieve time-sharing all-wheel-drive control. The strategy ensures the smooth switching of the system mode by identifying the working states of the two sets of power systems and the driving intention, and the controlling of hydraulic system to intervene and exit at the right time. In each mode, the pump displacement is controlled rationally, and a good wheel speed tracking in the assist mode is achieved. The actual vehicle test results of the control strategy show that the driver's operation intention is accurately identified, the mode switching and shift smoothness are good. The two systems work in harmony and do not interfere with each other, and the driving safety is guaranteed. The variable pump displacement response reasonably in each mode, and the wheel speed tracking method is effective. The actual vehicle test verifies the feasibility of the hub hydraulic hybrid system and the rationality of the strategy proposed.