Closed loop control of shifting clutch actuators in an automatic speed change transmission

摘要

A method of controlling hydraulic shift clutch actuators in an automatic speed change power transmission of the type having an electronic controller (TCU) for energizing a solenoid operated valve to control each hydraulic clutch actuator. A pressure sensor is disposed to sense the hydraulic pressure (Ps) to each clutch actuator and provides an electrical signal to the TCU which also receives a clutch pressure command signal (Pc) from the vehicle powertrain computer. The TCU computes the differential DeltaP=Pc-Ps and determines the valve energization current IE from known relationships between DeltaP and the percentage of maximum valve current and repeats the process in real time to adjust IE until DeltaP is negligible.