某自动挡车型制动前窜故障分析与改进

Malfunction Analysis and Improvement of Engine Speed Sharp Fluctuation at Braking of a Car with Automatic Transmission

针对某自主品牌自动挡车型出现的制动前窜故障,采用CAN网关、发动机ECU参数标定等技术手段对故障原因进行全面分析,发现引起该故障的主要原因为ECU与TCU的扭矩匹配问题。据此对ECU的部分扭矩控制参数进行更改和优化,同时对TCU的相关控制策略进行更改。对优化后的车辆在城市道路和高原环境中进行大量实车验证,结果表明,优化方案能有效解决制动前窜故障,且不会造成其他不良影响。

In order to solve the problem of engine speed sharp fluctuation at braking of a self-developed brand car with automatic transmission, technical means like CAN gateway and engine ECU parameter calibration etc are used to analyze the cause of this problem. It is found that torque adaptation between ECU and TCU are blamed for the problem. Accordingly, some torque control parameters of ECU are modified and optimized, and related control strategy of TCU is also modified. A large number of vehicle tests on both urban and highland driving conditions show that the solutions mentioned above are proved to be effective without adverse effect.