转速穿越冲击时的发动机转矩形状控制

Engine Torque Shape Control for Engine Speed Pass through Turbine Speed Condition

车辆传动系中不可避免地有齿轮副存在,由于齿面间有间隙,当主从动轮的传动状态发生切换时,便会产生冲击。在配备液力变矩器的车辆中,可以通过发动机转速和涡轮转速发生“转速穿越”的时刻来判断切换时机。控制在转速穿越时的发动机转矩形状可以针对性地优化此冲击,通过对比,整车纵向冲击程度和加速响应时间在ramp、platform、damp三种转矩形状下的表现,得出damp为最佳的发动机转矩控制形状,有效改善了转速穿越时的驾驶感受。

It is inevitable that there is a gear pair in the vehicle transmission system.Due to the clearance between the gear tooth surfaces,when the driving state of the master and slave driven wheels is switched,it will produce impact.In vehicles equipped with torque converter,the timing of switching can be detected by the moment of speed crossing when engine speed passes through turbine speed.The impact can be optimized by controlling the engine torque shape during the speed passage.By comparing the impact degree and acceleration response time obtained by the vehicle longitudinal acceleration signal under the ramp,platform and damp torque shapes,it′s conclude that the damp is the best engine torque control shape.It effectively improves the driving experience during speed crossing.