ELECTRIC DRIVE SYSTEM, POWERTRAIN, HEATING METHOD, AND ELECTRIC VEHICLE

An electric drive system and a heating method. The electric drive system includes an inverter circuit, a direct current-direct current conversion circuit, and a controller. An input end of the inverter circuit is connected to an input end of the electric drive system, and an output end of the inverter circuit is connected to three-phase motor windings of an electric excitation synchronous motor. An input end of the direct current-direct current conversion circuit is connected to the input end of the electric drive system, and an output end of the direct current-direct current conversion circuit is connected to an excitation winding of the electric excitation synchronous motor. In this solution, a heating apparatus does not need to be disposed when the power battery pack is heated, thereby reducing costs and saving space.