PERMANENT MAGNET ELECTRIC MACHINE HAVING AN INTEGRATED MAGNETIC FLUX SENSOR
A permanent magnet electric machine that includes a housing, a stator mounted within the housing, a rotor assembly, a plurality of permanent magnets mounted within the rotor assembly, and a magnetic flux sensor arranged within the housing. The magnetic flux sensor includes a sensing surface configured and disposed to detect magnetic flux leaking from the rotor assembly.
1 . A permanent magnet electric machine comprising:
a housing;
a stator mounted within the housing;
a rotor assembly rotatably mounted within the housing relative to the stator;
a plurality of permanent magnets mounted within the rotor assembly; and
a magnetic flux sensor arranged within the housing, the magnetic flux sensor including a sensing surface configured and disposed to detect magnetic flux leaking from the rotor assembly.
2 . The permanent magnet electric machine according to claim 1 , wherein the magnetic flux sensor is a non-contact temperature sensor.
3 . The permanent magnet electric machine according to claim 2 , wherein the non-contact temperature sensor is a Hall effect sensor.
4 . The permanent magnet electric machine according to claim 2 , wherein the non-contact temperature sensor is a search coil.
5 . The permanent magnet electric machine according to claim 1 , wherein the magnetic flux sensor is aligned with the plurality of permanent magnets.
6 . The permanent magnet electric machine according to claim 1 , further comprising: a coolant system configured and disposed to direct a flow of coolant to the electric machine.
7 . The permanent magnet electric machine according to claim 6 , further comprising: a water jacket extending about the housing.
8 . The permanent magnet electric machine according to claim 6 , wherein the coolant system directs the flow of coolant through the water jacket.
9 . The permanent magnet electric machine according to claim 6 , further comprising: a controller configured and disposed to deliver the flow of coolant through the housing based on magnetic flux sensed by the magnetic flux sensor.
10 . The permanent magnet electric machine according to claim 9 , wherein the controller is configured and disposed to determine a temperature of the plurality of permanent magnets based on the magnetic flux sensed by the magnetic flux sensor.
11 . The permanent magnet electric machine according to claim 1 , wherein the rotor assembly includes a plurality of laminations, the magnetic flux sensor being configured and disposed to detect magnetic flux leaking from the plurality of laminations.
12 . The permanent magnet electric machine according to claim 1 , wherein the magnetic flux sensor is configured and disposed to detect magnetic flux leaking from the plurality of permanent magnets.
13 . A method of operating a permanent magnet electric machine, the method comprising:
rotating a rotor assembly relative to a stator;
sensing magnetic flux leaking from the rotor assembly; and
controlling a parameter of the electric machine based on the magnetic flux leaking from the rotor assembly.
14 . The method of claim 13 , wherein controlling the parameter of the electric machine comprises controlling a flow of coolant through the electric machine.
15 . The method of claim 13 , wherein controlling the parameter of the electric machine comprises controlling output power of the electric machine.
16 . The method of claim 13 , wherein controlling the parameter of the electric machine comprises controlling rotational speed of the electric machine.
17 . The method of claim 13 , wherein controlling the parameter of the electric machine comprises controlling output torque of the electric machine.
18 . The method of claim 13 , wherein sensing magnetic flux leaking from the rotor assembly comprises sensing magnetic flux leaking from a plurality of laminations of the rotor assembly.
19 . The method of claim 18 , wherein sensing magnetic flux leaking from the rotor assembly comprises sensing magnetic flux leaking from permanent magnets of the rotor assembly.
20 . The method of claim 19 , further comprising: determining a temperature of one or more of the permanent magnets in the rotor assembly based on the magnetic flux.