Vehicle starting control method and system and vehicle

Abstract

The invention provides a vehicle starting control method and system and a vehicle, and the method comprises the steps that when it is detected that the vehicle has a starting demand, a whole vehicle power control unit PCU controls a power source torque and a clutch torque slope, and the power source torque, a clutch reference torque and a clutch offset torque act together to control the starting demand of the vehicle; finely the target transmission torque of the clutch is adjusted in real time according to the actual rotating speed of the power source, and the power source end rotating speed is guided to rise to the target rotating speed along with the guiding rotating speed until the power source rotating speed is synchronous with the gearbox input shaft rotating speed. According to the method, the power source end and the clutch load end are controlled, the fluctuation of the rotating speed of the power source end is weakened through the combined action of the clutch reference torque and the clutch offset torque, the stable torque output is ensured, and the good starting smoothness and dynamic property of the vehicle are obtained. Due to the fact that complex calculation is not needed, power assembly torque output and clutch transmission torque are determined, rotating speed fluctuation caused by PID closed-loop control is weakened, different stages of rotating speed rising do not need to be refined, and therefore control and calibration are easier.

Description

technical field [0001] The invention belongs to a control method in the field of vehicle power, in particular to all vehicle start control methods that control power transmission through clutch cut-off, engagement and slip friction. Background technique [0002] At present, vehicles that control power transmission through clutch cut-off, engagement and slip friction all start in a slip friction mode. Dry and wet clutches start with different slips, and wet clutches mostly use larger slips and local constant speed control. Through the speed closed loop, PID plays the main control role, and it is necessary to refine the speed rising stage, and most of the starting process has drivability problems such as sloshing and impact to varying degrees. The speed of clutch engagement and the smoothness of torque transmission directly determine the quality of the vehicle's starting drivability. Moreover, the PID value under a single working condition cannot adapt to complex and changea...

AI Technical Summary

Problems solved by technology

And the PID value under a single working condition cannot adapt to complex and changeable environmental working conditions, such as normal temperature and low temperature working conditions, different control methods will be adopted

If the moment of inertia of the power source is calculated as feed-forward, it cannot directly reflect the starting drivability of the vehicle, especially for starting with a wet clutch, and it is necessary to increase the role of PID adjustment, which brings complicated calibration and faces the above-mentioned PID adjustment. bring about problems

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