abstract |
In an electric machine, there may be lubrication and cooling needs, such as lubricating bearings and cooling coils of the electric machine. When lubricant is used for both, it is desirable to prioritize the lubrication to the bearings. By providing check valves between a pressurized oil manifold and the cooling coils, lubricant is diverted to the coils only when pressure in the system is sufficient to satisfy both lubrication and cooling. In some embodiments, an oil gallery is provided on an outside surface of a back iron of the stator of the electric machine and orifices are provided in the back iron so that oil drips onto the coils of the electric motor. In some embodiments, the current commanded to the electric motor is based on whether or not lubricant (or other coolant) is being provided to the coils. |