High-power multiphase electric machine with reduced mutual inductance interaction
Six-phase permanent magnet-type electric machines are disclosed. The electric machine includes a stator and a rotor configured to operate as a first three-phase electric machine and a second three-phase electric machine. The first and second three-phase electric machines are coupled with each other via a fractional slot combination with concentrated windings such that a mechanical separation between the first and second three-phase electric machines is at least 60 mechanical degrees.
1 . A six-phase electric machine comprising:
a stator and a rotor configured to operate as a first three-phase electric machine and a second three-phase electric machine,
the first and second three-phase electric machines coupled with each other via a fractional slot combination with concentrated windings,
the rotor comprising a plurality of V-shaped magnets, the number of V-shaped magnets equal to a number of poles in the six-phase electric machine, wherein each of the V-shaped magnets includes five (5) axially segmented components that are in a skewed orientation with respect to each other, wherein the skewed orientation defines a skew angle of 25 electrical degrees.
2 . The six-phase electric machine of claim 1 , the six-phase electric machine having a 10-pole configuration.
3 . The six-phase electric machine of claim 1 , wherein the six-phase electric machine has a winding factor of at least 95% and a slot harmonic distortion of less than 50%.
4 . The six-phase electric machine of claim 1 , wherein each leg of the V-shaped magnets comprises at least two separate segments of magnet.
5 . The six-phase electric machine of claim 1 , wherein a torque ripple resulting from an open fault of one of the first and second three-phase electric machines is less than 20%.
6 . The six-phase electric machine of claim 1 , wherein the six-phase electric machine is a medium duty motor with a power rating of between about 150 kW and 250 kW.
7 . The six-phase electric machine of claim 1 , wherein the six-phase electric machine is a heavy duty motor with a power rating of at least about 250 kW.
8 . The six-phase electric machine of claim 7 , wherein the power rating of the heavy duty motor is between about 250 kW and about 500 kW.
9 . The six-phase electric machine of claim 1 , wherein the first and second three-phase electric machines share a common neutral.
10 . The six-phase electric machine of claim 1 , wherein an electrical separation between the first and second three-phase electric machines is 15 electrical degrees.
11 . A vehicle comprising:
a motor controller; and
a six-phase electric motor electrically coupled with the motor controller and comprising:
a stator and a rotor configured to operate, by the motor controller, as a first three-phase electric motor and a second three-phase electric motor,
the first and second three-phase electric motors coupled with each other via a fractional slot combination with concentrated windings,
the rotor comprising a plurality of V-shaped magnets, the number of V-shaped magnets equal to a number of poles in the six-phase electric motor, wherein each of the V-shaped magnets includes five (5) axially segmented components that are in a skewed orientation with respect to each other, wherein the skewed orientation defines a skew angle of 25 electrical degrees.
12 . The vehicle of claim 11 , the six phase electric motor having a 10-pole configuration.
13 . The vehicle of claim 11 , wherein the six-phase electric motor has a winding factor of at least 95% and a slot harmonic distortion of less than 50%.
14 . The vehicle of claim 11 , wherein each leg of the V-shaped magnets comprises at least two separate segments of magnet.
15 . The vehicle of claim 11 , wherein a torque ripple resulting from an open fault of one of the first and second three-phase electric motors is less than 20%.
16 . The vehicle of claim 11 , wherein the six-phase electric motor is a medium duty motor with a power rating of between about 150 kW and 250 kW.
17 . The vehicle of claim 11 , wherein the six-phase electric motor is a heavy duty motor with a power rating of at least about 250 kW.
18 . The vehicle of claim 11 , wherein an electrical separation between the first and second three-phase electric motors is 15 electrical degrees.
19 . A six-phase electric machine comprising:
a stator and a rotor configured to operate as a first three-phase electric machine and a second three-phase electric machine, the first and second three-phase electric machines coupled with each other via a fractional slot combination with concentrated windings,
wherein an electrical separation between the first and second three-phase electric machines is 15 electrical degrees,
wherein the rotor includes a plurality of V-shaped magnets, the number of V-shaped magnets is equal to a number of poles in the six-phase electric machine, and each of the V-shaped magnets includes five (5) axially segmented components that are in a skewed orientation with respect to each other, wherein the skewed orientation defines a skew angle of 25 electrical degrees, and
wherein having the electrical separation of 15 electrical degrees facilitates a winding factor of at least 80% and a slot harmonic distortion of less than 50% for the six-phase electric machine.