Control method for pure electric starting process of hybrid car

Abstract

The invention discloses a method for controlling a pure electric start-up process of a hybrid electric vehicle. The method comprises the following steps: when a start-up request is recognized, sending a command for starting an auxiliary oil pump to a CAN network to make a clutch work in a half-junction; and when a brake pedal is released, controlling the revolving speed of a power motor to reach the set value, simultaneously controlling the clutch to start to transmit torque, a vehicle beginning start-up from being still, and completing the start-up process when the revolving speed of the clutch and the revolving speed of the motor are synchronous. According to the invention, the torque control PI parameter and the feedforward torque of the clutch are relevant to the electric quantity of the power motor, the torque of the clutch is corrected according to the electric quantity of the motor to prevent overload or runing away; the target revolving speed of the clutch takes the revolving speed of the motor as a reference point, the torque of the clutch is controlled segmentally, open-loop control ensures a rapid rise of the torque, closed-loop control makes the revolving speed of the clutch change by targeting at the target revolving speed in the start-up process, thus the start-up process of the vehicle is guaranteed to be smooth, and the start-up impact is avoided.

Description

technical field [0001] The invention relates to the field of hybrid electric vehicle control, in particular to a method for controlling the pure electric starting process of a hybrid electric vehicle. Background technique [0002] Hybrid vehicles have multiple operating modes such as hybrid, pure electric, drive-start, and park-start. When a hybrid electric vehicle starts purely electric, since the power motor has no idle speed, it can transmit torque to the gearbox at a very low speed. When starting at low speed in pure electric mode, there are auxiliary equipment to pre-fill the clutch with oil to make the clutch work at the half-engagement point, so that it can start quickly when the speed meets the conditions. During low-speed starting, the torque transmitted by the clutch can be adjusted by controlling the pressure of the clutch. At the same time, the torque transmitted by the clutch will in turn affect the speed of the motor. Therefore, it is necessary to precisely co...

AI Technical Summary

Problems solved by technology

In this patent, the control of clutch torque and motor speed during start-up is not involved

Images