MODULAR CRYOGENIC PERMANENT MAGNET ELECTRICAL MOTORS AND GENERATORSFOR SUBMERGED MOTOR PUMPS AND TURBINES AND RELATED SYSTEMS AND METHODS

1 . A motor assembly for use with a fluid handling device, comprising:

a motor housing;

a motor comprising a rotor and a stator contained in the motor housing, the motor comprising an alternating current medium voltage synchronous motor;

a first bearing assembly coupled to a first end of the motor housing; and

a second bearing assembly coupled to a second end of the motor housing and positioned at least partially within the motor housing, wherein the second bearing assembly is contained within a portion of the motor housing that is integral with another portion of the motor housing that surrounds the rotor and stator, the portion and the another portion of the motor housing configured to be collectively decoupled and demounted from the fluid handling device.

2 . The motor assembly of claim 1 , wherein the second bearing assembly is contained within a second bearing housing that is coupled to the motor housing to position the second bearing assembly within the motor housing.

3 . The motor assembly of claim 2 , wherein the second bearing housing is positioned within a lower mounting flange of the motor housing.

4 . The motor assembly of claim 3 , wherein the second bearing housing is bolted to the lower mounting flange of the motor housing.

5 . The motor assembly of claim 2 , the second bearing housing is configured to suspend the second bearing assembly within the motor housing by axially and radially supporting the second bearing assembly.

6 . The motor assembly of claim 1 , wherein the first bearing assembly is contained within a first bearing housing that is coupled to the motor housing.

7 . The motor assembly of claim 6 , wherein the first bearing housing is configured to suspend the first bearing assembly within the motor housing by axially and radially supporting the first bearing assembly.

8 . The motor assembly of claim 6 , wherein the first bearing housing is secured by bolting to an upper mounting flange of the motor housing.

9 . The motor assembly of claim 1 , wherein the first bearing assembly comprises a radial guide bearing and the second bearing assembly comprises two or more bearings for supporting a shaft.

10 . The motor assembly of claim 1 , wherein the motor housing, the first bearing assembly, and the second bearing assembly are configured to be collectively installed in and/or removed from a submergible cryogenic pump as a modular unit.

11 . A submergible cryogenic pump comprising:

fluid handling stages comprising impellers mounted to a shaft at least partially encompassed by one or more diffusers; and

a motor assembly for transferring force to and/or receiving force from the fluid handling stages via the shaft, the motor assembly comprising:

a motor housing;

a motor comprising a rotor and a stator contained in the motor housing; and

a bearing assembly for supporting the shaft, wherein the bearing assembly, the motor housing, and the motor contained in the motor housing are configured to be collectively decoupled and demounted from the fluid handling stages.

12 . The submergible cryogenic pump of claim 11 , wherein the motor further comprises an alternating current medium voltage synchronous motor configured to be driven at 1,000 Volts to 15,000 Volts and at a rotational speed between 2,000 RPM and 10,000 RPM.

13 . The submergible cryogenic pump of claim 11 , wherein the bearing assembly is contained within a bearing housing that is coupled to the motor housing to position the bearing assembly within the motor housing within a lower mounting flange of the motor housing.

14 . The submergible cryogenic pump of claim 11 , wherein the shaft is configured to move axially within the motor housing.

15 . A method of providing a modular motor assembly for a fluid handling device, the method comprising:

coupling a motor assembly to a fluid handling device comprising fluid handling stages including impellers mounted to a shaft at least partially encompassed by one or more diffusers, the motor assembly for transferring force to and/or receiving force from the fluid handling stages via the shaft, the motor assembly comprising a motor housing and a motor comprising a rotor and a stator integrally contained in the motor housing;

supporting the shaft with more than one bearing assemblies integrally contained in the motor housing; and

collectively decoupling and demounting the motor assembly including the motor housing and integrally contained components of the rotor, the stator, and the more than one bearing assemblies from the fluid handling device.

16 . The method of claim 15 , further comprising, after servicing at least a portion of the motor assembly, recoupling and remounting the motor assembly including the integrally contained components of the rotor, the stator, and the more than one bearing assemblies to the fluid handling device.

17 . The method of claim 15 , further comprising, after replacing at least a portion of the motor assembly, installing the replacement motor assembly on the fluid handling device.

18 . The method of claim 15 , further comprising positioning the more than one bearing assemblies within at least one bearing housing that is coupled to the motor housing to position and support the more than one bearing assemblies within the motor housing.

19 . The method of claim 18 , further comprising independently removing the at least one bearing housing with the more than one bearing assemblies while other elements of the motor assembly are not disturbed.

20 . The method of claim 18 , further comprising suspending the more than one bearing assemblies within the motor housing by axially and radially supporting the more than one bearing assemblies with the at least one bearing housing.