| Abstract:Extended-range electric vehicles are more and more favored by the market because of their long driving range, significant energy-saving and emission reduction effects, simple power structure and other characteristics, but the extended-range power system engine and motor are currently using two sets of independent cooling systems, resulting in heavy structure and high cost. To this end, taking an extended-range light truck as the research object, the engine and motor of the extended-range power system are designed with an integrated cooling system. In the preset operating conditions, the heat dissipation requirements of the range extender and the electric drive system are calculated through tests, and the coolant and cooling water pump are selected and matched. The one-dimensional simulation model of the range extender and the cooling circuit of the electric drive system is established, and the cooling effect and energy consumption of the series and parallel cooling pipes of the electric drive system are compared and analyzed, and the feasibility of the coolant of the drive motor to help the engine cold start is verified. The results show that the electronic water pump can control the coolant flow more efficiently and accurately, and the cooling effect is better. In one-dimensional simulation analysis of the cooling system, the temperature rise curve can directly see that the cooling effect of the parallel cooling pipeline is better, and the solenoid valve in the parallel pipeline can control the opening size according to different working conditions, and the cooling is more efficient than the unified control of the series pipeline coolant flow. Heat is generated quickly when the drive motor is cooled in the parallel cooling pipeline, and thermal interaction with the engine during cold start can help the engine warm up quickly, and improve the problem of poor emissions and weak power of the engine during cold start. |