Gear shifting intervention control method of two-gear drive-by-wire automatic transmission of electric car

Abstract

The invention discloses a gear shifting intervention control method of a two-gear drive-by-wire automatic transmission of an electric car. According to the method, a D gear switching signal, a rotating speed signal n2 of a rotating speed sensor of a transmission output shaft, a rotating speed signal n1 of a rotating speed sensor of a motor and an opening signal alpha of a position sensor of an accelerator pedal are detected by an electronic control unit of the transmission, so that whether a first gear needs to be shifted to a second gear and the second gear needs to be shifted to the first gear is determined, and intervention control over the rotating speed of the motor is performed during gear shifting. For example, when the first gear needs to be shifted to the second gear, the target rotating speed of the motor for shifting the first gear to the second gear is determined according to a target rotating speed function of the motor for shifting the first gear to the second gear, the rotating speed of the motor is controlled to reach the target rotating speed of the motor for shifting the first gear to the second gear by the electronic control unit of the motor, and the intervention control over the upshifting process of the drive-by-wire automatic transmission is performed, so that stable upshifting of the drive-by-wire automatic transmission is realized.

Description

technical field [0001] The invention relates to a control method of an automatic transmission, more precisely, a shift intervention control method for a two-speed wire-controlled automatic transmission of an electric vehicle. Background technique [0002] Automatic transmissions are widely used in various vehicles such as automobiles, electric vehicles, and construction machinery. The existing automatic transmissions mainly include hydromechanical automatic transmission (AT), metal belt continuously variable automatic transmission (CVT), mechanical automatic transmission (AMT) and dual clutch automatic transmission (DCT). [0003] The above-mentioned four types of automatic transmissions all adopt electronically controlled hydraulic servo devices to realize the control of the shifting process, which has complex structure, high cost and increased control difficulty and complexity. In particular, the executive mechanism of DCT includes: oil supply mechanism composed of hydrau...

AI Technical Summary

Problems solved by technology

[0005] In order to realize the power shift of the wire-controlled automatic transmission, that is, the driver does not need to interrupt the power between the electric motor and the wire-controlled automatic transmission during the shifting process. If the intervention control of the motor is not used, the motor speed cannot meet the shifting speed during the shifting process. requirements, causing shift shock and reducing the life of the electric motor and automatic transmission by wire

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