Range extender cold start control method, vehicle control unit, system and electric vehicle

Abstract

The invention discloses a range extender cold start control method, a vehicle control unit, a system and an electric vehicle. The method comprises the steps that the temperature of an engine is obtained; a target rotating speed for starting a range extender is obtained according to the temperature of the engine, and the target rotating speed and a rotating speed mode control instruction are sent to a generator controller, so that the generator controller controls a generator to enter a rotating speed mode and controls the generator to rotate according to the target rotating speed; after the generator rotates at the target rotating speed and drives the engine to run, a torque mode control instruction is sent to the generator controller according to a running signal of the engine, so that the generator controller controls the generator to exit the rotating speed mode and enter the torque mode; and after the engine runs, a heat engine mode control instruction is sent to an engine controller, so that the engine controller adjusts the rotating speed of the engine according to the temperature of the engine until the engine is heated. The problem of overspeed of the engine during cold start of the range extender is solved.

Description

technical field [0001] The invention relates to the technical field of range-extended electric vehicles, in particular to a cold-start control method for a range-extender, a vehicle controller, a system, and an electric vehicle. Background technique [0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art. [0003] The range-extended electric vehicle has the advantages of low vehicle cost, long cruising range, no need for complicated mechanical transmission devices, and cleanliness and high efficiency. The main structural difference between the extended-range electric vehicle and the pure electric vehicle is that the extended-range electric vehicle adds a range extender , The range extender is composed of the engine, the engine controller ECU, the generator and the generator controller GCU. The engine drives the generator to rotate and generate electricity to provide energy for ...

AI Technical Summary

Problems solved by technology

[0004] The starting method of the range extender is different from that of the traditional car. The engine of the traditional car is started by the starter, and the start of the range extender is started by the generator ;Under normal temperature conditions, the engine does not need a warm-up engine, and the generator will start the engine, and the engine will not over-speed. The idle target speed of the engine will increase, and the engine will appear over-speed phenomenon. The over-speed phenomenon refers to the target speed of 1500rpm, and it will reach 3000rpm after over-speed, which will affect the starting comfort and fuel consumption of the whole vehicle.

[0005]The existing technology is to drive the engine to rotate through the generator. During the process of driving the engine by the generator, the generator sets a constant speed, and the engine is rotated according to the gradient of the generator speed. Increase the speed to the required target speed; but this method has the following problems: (1) The control method is an open-loop control, and the actual speed of the engine cannot be adjusted according to the target speed of the generator; (2) During the cold start of the engine, the power generation The target speed of the engine driven by the engine is 1500rpm. Since the engine is in a cold state and the engine enters a hot state, the engine speed requirement is 1800rpm, so the target speed of the engine does not match the actual required speed. The engine is corrected by increasing the amount of air and fuel injection. There will be over-speed phenomenon

Images