A control method, system and device for smooth shifting of a hybrid electric vehicle

Abstract

The invention discloses a control method, system and device for smooth shifting of a hybrid electric vehicle. The hybrid electric vehicle includes an engine, a motor and a dual-clutch gearbox. The method includes: receiving a shift request when the vehicle is in a preset working condition; Acquire the first output torque and the target output torque of the motor according to the gear shift request; control the combination of the engine and the dual-clutch gearbox, and at the same time unload the output torque of the motor from the first output torque to zero; calculate the first slope; based on the first slope The output torque of the control engine is loaded from zero to the second output torque; the output torque of the motor is controlled from zero to the target output torque, and the output torque of the engine is unloaded from the second output torque to zero based on the first slope. The invention controls the change of the output torque of the engine according to the change of the motor torque, maintains the smooth deceleration feeling of the whole vehicle, reduces the acceleration fluctuation caused by torque loss during gear shifting, and further improves the smoothness of gear shifting.

Description

technical field [0001] The invention relates to the technical field of automobiles, in particular to a control method, system and device for smooth shifting of a hybrid electric vehicle. Background technique [0002] With the improvement of living standards, the number of car ownership is increasing. Under the background of new energy constraints and environmental pollution, new energy vehicles represented by electric vehicles stand out and become the first choice of many people. [0003] Electric vehicles are driven by electric energy. However, during the braking process of the vehicle, the kinetic energy of the vehicle will be converted into heat through friction and consumed, resulting in a large amount of energy being wasted. According to relevant research data, under several typical urban working conditions, the energy consumed by friction braking during braking accounts for about 50% of the total driving energy of the vehicle. Electric vehicle braking energy recovery...

AI Technical Summary

Problems solved by technology

[0004] For reasons such as environmental protection and energy saving, hybrid vehicles have been more and more widely recognized and used by countries all over the world. In the prior art, due to the physical characteristics of traditional transmissions, the transmission ratio of the engine changes during gear shifting, resulting in gear shifting. During the process, the torque transmitted to the wheel ends decreases, resulting in fluctuations in acceleration

Especially when shifting gears in low gear, the transmission ratio changes greatly, and the corresponding wheel end torque loss is also large, resulting in uneven gear shifting, which in turn affects the driving stability of hybrid electric vehicles; traditional hybrid electric vehicles have a variety of hybrid structures , P2.5 structure hybrid vehicles are widely used, but when P2.5 structure hybrid vehicles are in the state of pure electric coasting, the motor recovers part of the kinetic energy to control the vehicle deceleration, but if the motor shifts gears, the motor torque needs to be first Unload to zero and then reload. At this time, the whole vehicle will lose the feeling of deceleration, and the illusion of sudden acceleration will appear.

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