A model for power shift system is built for dynamically analyzing the torque phase in up shift process of automatic transmission. Aiming at the problem of shift shock with traditional control strategy, an ideal control objective for torque phase is proposed based on the requirements of improving shift smoothness. A varying torque changing rate is adopted to replace the constant one in traditional control strategy and an open-loop adaptive control strategy is formulated. A model reference adaptive controller is designed to reduce the disturbance caused by the changes of temperature and loading, and an adaptive correction is made on the parameters of open-loop control with the changing rate of the rotation speed difference in off-going clutch as feedback variable. The results of real vehicle test verify that the control strategy proposed can effectively reduce the shift shock in automatic transmission.%为动态分析自动变速器换挡过程中的转矩相,建立了动力换挡系统模型.针对传统控制策略所产生的换挡冲击问题,基于改善换挡平顺性的要求提出理想转矩相的控制目标,以变化的转矩变化率代替传统控制策略固定的转矩变化率.为减小油温、载荷等工况的变化对转矩相控制过程的扰动,设计了模型参考自适应控制器,并以待分离离合器速差的变化率作为反馈变量对开环控制参数进行自适应修正.实车试验验证了所提出的控制策略可有效减小自动变速器的换挡冲击.
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