Robust Stabilization of Slip Control System for Torque Converter Lock-up Clutch Using H-Infinity Control Theory (2nd Report, Evaluation Test on Vehicle)

Abstract

In previous paper, H-infinity control theory was applied in order to establish high reliability of a torque converter lock-up clutch slip control system. In this paper, evaluation test on vehicle is done after the controller is transformed so as to maintain the designed characteristics for implementation into an onboard ECU. As a result it is confirmed that robust stability against large variation under vehicle operating conditions and variation induced by aging deterioration is ensured. However it is found that there is a limit of improvement in performance with the controller adopting fixed gain because of the large variation in the system. So we propose characteristic variation compensating which compensates for the variation with only a few parameters in order that the characteristics of plant realized by feedback controller become invariant, so that the high performance can be achieved. The result in the system shows that the proposed filter makes the performance improve several times.