H/sup ∞/ control design for torque-converter-clutch slip system

Abstract

This paper describes the development of a robust feedback controller for the torque-converter-clutch slip control system mounted in the Toyota A245E automatic trans-axle. H/sup /spl infin// control theory was applied as a systematic design method in order to ensure robust stability against large variation in characteristics under vehicle operating conditions and variation in friction characteristics of the clutch induced by aging deterioration. This theory enables a detailed design in the frequency domain. As a result, the control system achieves high levels of response and reliability, which contribute to a large-scale reduction of fuel consumption.