A study on the speed governing strategy of hydraulic torque converter lock-up process

Considering the double demands of power performance and lock-up quality for the lock-up process of hydraulic torque converter, a lock-up control strategy based on engine speed governing was proposed. Through analyzing the effects on lock-up impacts from the sliding-friction moment of lock-up clutch and inertial energy releasing of the engine, lock-up process control was realized by taking the sliding-friction velocity of lock-up clutch, instead of the position of accelerator pedal, as the input excitation of diesel engine speed governing system. The strategy was testified by an actual test with a certain tracked vehicle. The test results indicate that the lock-up control strategy based on engine speed governing can implement a smooth and fast lock-up process without losing power performance of the vehicle.