Method for determining solenoid control current using hysteresis interpolation for transmission clutch control

摘要

A transmission control arrangement controls the generation of a required solenoid control current that is provided to an electro-hydraulic pressure control module to ultimately control clutch pressure. The module includes a linear solenoid, which has an up direction pressure-current (P-I) data table and a down direction pressure-current (P-I) data table associated therewith. For large pressure increase change requests the up P-I table is used. For large pressure decrease change requests the down P-I table is used. An interpolation process uses current values taken from both the up and down P-I data tables for pressure change requests that are neither large increases nor large decreases. The control arrangement also includes a variable gain feature that changes the gain in dependence on the gear state of the transmission.