Pure electric drive start control method for hybrid electric vehicle

The invention relates to a pure electric drive start control method for a hybrid electric vehicle. The method includes the steps that in pure electric start of the whole vehicle, a drive motor is controlled to enter rotating speed closed-loop control, wherein it is required that the rotating speed of the drive motor is kept equal to a target rotating speed; a clutch in a gearbox is controlled to be engaged slowly; the drive motor controls the whole vehicle to start slowly through the gearbox, and then the whole vehicle enters a crawling condition to run; when the system runs in a crawling mode and a driver steps on an accelerator for acceleration, the drive motor is controlled to quit from rotating speed closed-loop control, and torque control is preformed on the drive motor, wherein actuating torque of the drive motor is the superposition of actual torque of the drive motor under the crawling condition and torque needed by the driver. By means of the method, the rotating speed and torque of the drive motor can be well controlled, and joggling of the whole vehicle is prevented.