Energy-saving control method and device for pure electric vehicle and vehicle control unit

The invention provides an energy-saving control method and device for a pure electric vehicle and a vehicle control unit, and belongs to the technical field of electric vehicles. The method comprises the steps that when the vehicle is powered on, a cooling fan and a pump body are controlled to run at an idle speed for a target duration and then stop, and safety self-inspection is conducted; and in the vehicle running process, under the condition that the motor water temperature of the main drive motor is determined to reach the lowest starting limit value of a motor cooling water channel based on the water temperature signal, a cooling fan is controlled to be started, and the working rotating speeds of the cooling fan and an electronic water pump are adjusted based on the motor water temperature. According to the invention, the cooling fan and the pump body are controlled to stop after running for the target duration at the idle speed, safety self-inspection is carried out, and the working rotating speeds of