Excitation unit cooling system of motor, electrically excited synchronous motor, driving assembly and vehicle

The invention discloses an excitation unit cooling system of a motor, an electro-magnetic synchronous motor, a driving assembly and a vehicle, and the excitation unit cooling system of the motor comprises a rotor shaft which is internally provided with a main cooling flow path; at least one part of the excitation unit is arranged on the rotor shaft in a sleeving manner; wherein the rotor shaft is provided with a main cooling liquid outlet communicated with the main cooling flow path, and the main cooling liquid outlet is communicated with the excitation unit, so that the cooling liquid in the main cooling flow path can be conveyed to the excitation unit. Therefore, the excitation unit cooling system of the motor directly cools the excitation unit, the cooling speed of the excitation unit can be increased, and the cooling efficiency of the excitation unit can be improved. 本发明公开了一种电机的励磁单元冷却系统、电励磁同步电机、驱动总成和车辆，该电机的励磁单元冷却系统包括：转子轴，转子轴内形成有主冷却流路；励磁单元，励磁单元的至少一部分套设于转子轴；其中，转子轴设有与主冷却流路连通的主冷却液出口，主冷却液出口与励磁单元连通，从而可以将主冷却流路中的