With an advanced foreign hydraulic automatic transmission as the objective,an analytical method for the gear-shifting schedule is proposed.First the demanded maximum gradient of test is estimated.Then a test scheme an...With an advanced foreign hydraulic automatic transmission as the objective,an analytical method for the gear-shifting schedule is proposed.First the demanded maximum gradient of test is estimated.Then a test scheme and analytical procedure is formulated by initial test and hypothetical shift parameters.Finally through gear-shifting tests under different road conditions,load,accelerator pedal position limitation,throttle opening and output shaft speed are found to be the gear-shifting parameters.Under a common road condition,the gear-shifting schedule is a double-parameter schedule.Based on the driver＇s demands on braking and dynamic performance,different shift schedules are made under downhill,uphill and quick releasing acceleration pedal conditions.The operation criteria of down-shift schedule on abrupt grade are proposed.展开更多
The performance of electric vehicles is affected by the shift quality of multi-gear transmission.The realization of dual-target tracking control requires the transmission control unit(TCU)to accurately measure and pro...The performance of electric vehicles is affected by the shift quality of multi-gear transmission.The realization of dual-target tracking control requires the transmission control unit(TCU)to accurately measure and process the input signals of the gear-shifting control system and precisely control the drive motor torque and the position of shift motors.An electric-vehicle-dedicated TCU was designed to meet the above design requirements.Its function modules included a single-chip control circuit,shift position signal sampling circuit,signal conditioning circuit of the rotational speed and angle,controller area network communication circuit,and shift motor drive circuit.A hardware-in-the-loop simulation test system showed that the TCU design scheme met measurement accuracy requirements and coordinated the actions of the shift actuator and motor control unit to achieve fast and smooth shifting before the road test.The power interruption time of the shifting process was within 350 ms.The reliability of the TCU design was further verified in a 150,000-km vehicle road test.展开更多
基金Supported by the National High Technology Research and Development Program of China(863 Program)(2012AA112101)
文摘With an advanced foreign hydraulic automatic transmission as the objective,an analytical method for the gear-shifting schedule is proposed.First the demanded maximum gradient of test is estimated.Then a test scheme and analytical procedure is formulated by initial test and hypothetical shift parameters.Finally through gear-shifting tests under different road conditions,load,accelerator pedal position limitation,throttle opening and output shaft speed are found to be the gear-shifting parameters.Under a common road condition,the gear-shifting schedule is a double-parameter schedule.Based on the driver＇s demands on braking and dynamic performance,different shift schedules are made under downhill,uphill and quick releasing acceleration pedal conditions.The operation criteria of down-shift schedule on abrupt grade are proposed.
基金This work was supported by the National Natural Science Foundation of China(51775291)Provincial-College Cooperation Project(2019YFSY0008)Sichuan Science and Technology Project(Grant No.2019JDRC0002).
文摘The performance of electric vehicles is affected by the shift quality of multi-gear transmission.The realization of dual-target tracking control requires the transmission control unit(TCU)to accurately measure and process the input signals of the gear-shifting control system and precisely control the drive motor torque and the position of shift motors.An electric-vehicle-dedicated TCU was designed to meet the above design requirements.Its function modules included a single-chip control circuit,shift position signal sampling circuit,signal conditioning circuit of the rotational speed and angle,controller area network communication circuit,and shift motor drive circuit.A hardware-in-the-loop simulation test system showed that the TCU design scheme met measurement accuracy requirements and coordinated the actions of the shift actuator and motor control unit to achieve fast and smooth shifting before the road test.The power interruption time of the shifting process was within 350 ms.The reliability of the TCU design was further verified in a 150,000-km vehicle road test.
