Method of operating an electric machine having an integrated coolant level sensor

1. A method of operating an electric machine, the method comprising:

flowing a coolant into an interior portion of a housing of the electric machine; and

sensing a level of coolant in a coolant collection area within the interior portion with a coolant level sensor mounted to a wall of the housing.

2. The method of claim 1 , further comprising: sending a signal indicating a level of coolant in the coolant collection area from the coolant level sensor to a controller.

3. The method of claim 1 , further comprising: controlling the flow of coolant based on the level of coolant in the coolant collection area.

4. The method of claim 1 , further comprising: signaling an alarm if the coolant in the coolant collection area rises above a predetermined level.

5. The method of claim 4 , further comprising: initiating an electric machine shut down if the coolant in the coolant collection area rises above the predetermined level.

6. The method of claim 1 , wherein sensing a level of coolant in the coolant collection area includes sensing a change in capacitance of the coolant level sensor.

7. The method of claim 1 , further comprising: signaling an alarm if the coolant in the coolant collection area falls below a predetermined level.

8. The method of claim 7 , further comprising: shutting down the electric machine if the level of coolant in the coolant collection area falls below the predetermined level.

9. The method of claim 1 , wherein sensing the level of coolant in a coolant collection area includes directly sensing a level of coolant with a coolant level sensor mounted in the housing.

10. The method of claim 1 , wherein sensing a level of coolant in a coolant collection area comprises sensing the level of coolant through a wall of the housing.

11. The method of claim 1 , further comprising: ceasing the flow of coolant if the level of coolant in the coolant collection area contacts moving components of the electric machine.