High temperature alternator for geothermal applications
Among other things, the present disclosure relates to an alternator for high temperature applications, (i.e., an alternator capable of operating at temperatures greater than approximately 250° C.). The alternator for high temperature applications may include permanent magnets arranged in a topology which may enable the alternator and connected application system to start operating without an external or auxiliary power source. When used in geothermal applications, the alternator may be capable of using drilling fluid as a coolant.
1 . An alternator for high temperature applications, the alternator comprising:
a stator having an interior; and
a rotor comprises a permanent magnet pole embedded within the rotor; wherein:
the rotor is concentrically positioned within the interior of the stator, and
the permanent magnet pole comprises samarium cobalt (SmCo);
the alternator is configured to have a power rating of about 35 kW when the rotor has a speed of about 900 rpm and the alternator is at a temperature of about 350° C.
2 . The alternator of claim 1 , further comprising:
a rotor shaft which is substantially concentric to the stator and the rotor; wherein:
the shaft comprises a hole, and
a fluid is configured to flow through the hole.
3 . The alternator of claim 2 , wherein:
the fluid comprises a drilling fluid.
4 . The alternator of claim 3 , wherein:
the drilling fluid is configured to cool the alternator.
5 . The alternator of claim 1 , wherein:
the alternator is capable of operating at temperatures greater than approximately 200° C.
6 . The alternator of claim 1 , wherein:
the permanent magnet pole comprises a V-type double layer formation,
the V-type double layer formation comprises a first permanent magnet pole and a second permanent magnet pole meeting at an angle, and
the angle comprises greater than approximately 90°.
7 . The alternator of claim 1 , wherein:
the stator comprises greater than 25 slots.
8 . The alternator of claim 7 , wherein:
the stator comprises 27 slots.
9 . The alternator of claim 7 , wherein:
the stator has a double layer winding, and
the stator has a 4 slot span.
10 . The alternator of claim 9 , wherein:
the double layer winding comprises greater than 4 turns.
11 . The alternator of claim 9 , wherein:
the double layer winding comprises 5 turns, and
the double layer winding comprises 10 turns per slot.