Motor compressor unit with magnetic bearings

Patent metadata

Field	Value
Publication number	US-10151316-B2
Application number	US-201515533197-A
Country	US
Kind code	B2
Filing date	Nov 26, 2015
Priority date	Dec 5, 2014
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

A motor-compressor unit for sub-sea applications, including a pressure casing, and an electric motor housed in a motor compartment formed in the pressure casing and a compressor housed in a compressor compartment formed in the pressure casing. A shaft drivingly connects the electric motor and the compressor. At least one magnetic bearing rotatingly supports the shaft and a control system is provided for controlling the magnetic bearing. The control system is housed in a control system compartment structurally connected to and supported by the pressure casing.

First claim

What is claimed is:

1. A motor-compressor unit for subsea applications, the motor-compressor unit comprising:
a pressure casing having a main casing portion and an auxiliary casing portion sealingly connected to one another and having a partition wall therebetween;
an electric motor housed in a motor compartment formed in the pressure casing;
a compressor housed in a compressor compartment formed in the pressure casing;
a shaft drivingly connecting the electric motor and the compressor;
at least one magnetic bearing rotatingly supporting the shaft; and
a control system for controlling the magnetic bearing housed in a control system compartment arranged within the auxiliary casing portion;
wherein the partition wall comprises first electric connectors on a first surface of the partition wall and second electric connectors on a second surface of the partition wall, each of the first electric connectors being electrically coupled to a respective one of the second electric connectors.

2. The motor-compressor unit of claim 1 , wherein the control system compartment is integrated within the pressure casing.

3. The motor-compressor unit of claim 1 , wherein the motor compartment is arranged between the control system compartment and the compressor compartment.

4. The motor-compressor unit of claim 1 , wherein the compressor compartment is arranged between the motor compartment and the control system compartment.

5. The motor-compressor unit claim 1 , wherein wirings electrically connecting the control system and the at least one magnetic bearing are entirely housed within the pressure casing.

6. The motor-compressor unit of claim 1 , wherein the main casing portion houses at least one of the motor compartment and the compressor compartment.

7. The motor-compressor unit of claim 1 , wherein the auxiliary casing portion comprises a connector flange, where through electric power and/or electric signal cables enter the control system compartment.

8. The motor-compressor unit of claim 1 , wherein the main casing portion has a first mounting flange and the auxiliary casing portion has a second mounting flange, the auxiliary casing portion and the main casing portion being connected to one another at the first mounting flange and second mounting flange.

9. The motor-compressor unit of claim 1 , wherein the control system compartment is filled with inert gas.

10. The motor-compressor unit of claim 9 , wherein an inert gas pressure inside the control system compartment is below a pressure inside the pressure casing.

11. The motor-compressor unit of claim 1 , wherein the first surface faces the auxiliary casing portion and the second surface faces the main casing portion.

12. The motor-compressor unit of claim 1 , wherein the main casing portion comprises an inner flange provided with electric connectors configured and arranged for electrically connecting wirings of the magnetic bearing to the second electric connectors of the partition wall.

13. The motor-compressor unit of claim 1 , wherein the partition wall is connected to a cooling medium duct extending therethrough.

14. The motor-compressor unit of claim 13 , wherein the cooling medium duct is fluidly coupled to a cooling medium inlet flange arranged on the pressure casing.

15. The motor-compressor unit of claim 13 , wherein the cooling medium duct is fluidly coupled to the motor compartment, and wherein a cooling medium fan is arranged in the motor compartment.

16. The motor-compressor unit of claim 15 , wherein the cooling medium fan is mounted on the shaft.

17. A method of connecting a control system to at least one magnetic bearing in a motor-compressor unit, the method comprising:
arranging a pressure casing having at least a main casing portion and an auxiliary casing portion and a partition wall therebetween;
mounting at least one magnetic bearing in the main casing portion;
arranging the control system in the auxiliary casing portion;
electrically connecting the control system and the at least one magnetic bearing to one another;
sealingly connecting the auxiliary casing portion and the main casing portion to one another; and
arranging first electric connectors on a first face of the partition wall, and second electric connectors on a second surface of the partition wall; each of the first electric connectors being electrically coupled to a respective one of the second electric connectors.

18. The method of claim 17 , further comprising mounting a compressor in a compressor compartment formed in the main casing portion of the pressure casing and an electric motor in an electric motor compartment formed in the main casing portion, the compressor and the electric motor being drivingly connected by a shaft supported by at least the one magnetic bearing.

19. The method of claim 17 , further comprising arranging the partition wall such that the control system compartment formed in the auxiliary casing portion is separated from an inner volume of the main casing portion.

20. The method of claim 19 , wherein the electrically connecting the control system and the magnetic bearing to one another further comprises:
electrically connecting the control system to the first electric connectors;
electrically connecting the magnetic bearing to the second electric connectors; and
arranging the partition wall between the control system compartment and the inner volume of the main casing portion before sealingly connecting the auxiliary casing portion and the main casing portion to one another, the first surface of the partition wall being oriented towards the control system compartment and the second face being oriented towards the interior of the main casing portion.

21. The method of claim 20 , wherein connecting the magnetic bearings to the second electric connectors comprises:
arranging an inner flange in the main casing portion;
arranging electric connections across the inner flange;
electrically connecting the magnetic bearings to one side of the inner flange; and
electrically connecting the second electric connectors of the partition wall to the other side of the inner flange.

22. A motor-compressor unit comprising:
a pressure casing;
an electric motor housed in a motor compartment formed in the pressure casing;
a compressor housed in a compressor compartment formed in the pressure casing;
a shaft drivingly connecting the electric motor and the compressor;
at least one magnetic bearing rotatingly supporting the shaft; and
a control system for controlling the magnetic bearing;
wherein the control system is housed in a control system compartment structurally connected to and supported by the pressure casing,
wherein the pressure casing comprises a main casing portion and at least an auxiliary casing portion sealingly connected to one another to form at least a part of the pressure casing, and wherein the control system compartment is arranged in the auxiliary casing portion,
a partition wall between the auxiliary casing portion and the main casing portion to sealingly isolate the control system compartment formed in the auxiliary casing portion from an inner volume of the main casing portion; and
wherein the partition wall comprises first electric connectors on a first surface of the partition wall and second electric connectors on a second surface of the partition wall, the first surface facing the auxiliary casing portion and the second face facing the main casing portion, each of the first electric connec

Assignees

• Nuovo Pignone Srl

Inventors

• Camatti Massimo
• Esposito Roberto
• Ortiz Neri Massimiliano
• Bigi Manuele

Classifications

• F04D25/0693

  Details or arrangements of the wiring · CPC title

• F04D25/0686

  specially adapted for submerged use · CPC title

• F04D29/5806

  Cooling the drive system · CPC title

• F04D29/00

  Details, component parts, or accessories (machine elements in general F16) · CPC title

• F04D17/00

  Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps (F04D21/00 takes precedence) · CPC title