SG178355A1 - Permanent magnet motor for subsea pump drive - Google Patents
Permanent magnet motor for subsea pump drive Download PDFInfo
- Publication number
- SG178355A1 SG178355A1 SG2012009379A SG2012009379A SG178355A1 SG 178355 A1 SG178355 A1 SG 178355A1 SG 2012009379 A SG2012009379 A SG 2012009379A SG 2012009379 A SG2012009379 A SG 2012009379A SG 178355 A1 SG178355 A1 SG 178355A1
- Authority
- SG
- Singapore
- Prior art keywords
- pump drive
- subsea pump
- motor
- rotor
- drive motor
- Prior art date
Links
- 239000012530 fluid Substances 0.000 claims abstract description 10
- 238000012546 transfer Methods 0.000 claims abstract description 10
- 238000005260 corrosion Methods 0.000 claims abstract description 7
- 230000007797 corrosion Effects 0.000 claims abstract description 7
- 238000001816 cooling Methods 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 13
- 239000012809 cooling fluid Substances 0.000 claims description 11
- 239000013535 sea water Substances 0.000 claims description 7
- 238000010292 electrical insulation Methods 0.000 claims description 2
- 230000004044 response Effects 0.000 claims description 2
- 230000006698 induction Effects 0.000 abstract description 6
- 239000000696 magnetic material Substances 0.000 abstract description 2
- 229910001026 inconel Inorganic materials 0.000 abstract 1
- 238000005086 pumping Methods 0.000 description 10
- 238000013459 approach Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 241000252067 Megalops atlanticus Species 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D13/00—Pumping installations or systems
- F04D13/02—Units comprising pumps and their driving means
- F04D13/06—Units comprising pumps and their driving means the pump being electrically driven
- F04D13/0606—Canned motor pumps
- F04D13/064—Details of the magnetic circuit
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D13/00—Pumping installations or systems
- F04D13/02—Units comprising pumps and their driving means
- F04D13/06—Units comprising pumps and their driving means the pump being electrically driven
- F04D13/08—Units comprising pumps and their driving means the pump being electrically driven for submerged use
- F04D13/086—Units comprising pumps and their driving means the pump being electrically driven for submerged use the pump and drive motor are both submerged
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/58—Cooling; Heating; Diminishing heat transfer
- F04D29/586—Cooling; Heating; Diminishing heat transfer specially adapted for liquid pumps
- F04D29/588—Cooling; Heating; Diminishing heat transfer specially adapted for liquid pumps cooling or heating the machine
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
- Motor Or Generator Frames (AREA)
- Motor Or Generator Cooling System (AREA)
Abstract
A subsea pump drive (10) employs a permanent magnet (PM) motor (12) to drive a subsea pump (40). The PM motor rotor in one embodiment is canned with a non-magnetic material such as inconel that can provide a desired level of corrosion protection The PM motor provides a subsea pump drive that is smaller and more efficient, having a high power factor than a subsea pump drive utilizing a conventional induction motor. The PM motor subsea pump drive eliminates the necessity for a topside storage tank and associated fluid transfer lines when the motor rotor is cooled with processed fluid.
Description
PERMANENT MAGNET MOTOR
FOR
SUBSEA PUMP DRIVE
[0001] The invention relates generally to subsea pumping systems and methods, and more specifically a canned permanent magnet motor fiw a subsea pump drive.
[0002] The need for subsea pumps in the oil and gas industry has been increasing due to increasing energy requirements, and because onshore energy sources are becoming more scarce. These industries must now look for energy sources offshore; and the distance between shore and subsea fields continues lo mncrease.
[0003] Electrical motors have been selected as a standard to drive the subsea pumps due to ease of power transfer over long distances when compared to other drive systems and methods, ncludmg, for example, hydraulic driven pumps.
Conventional systems and methods employ induction motors for driving the aforesmd subsea pumps. Use of mduction type motors has been problematic however, since induction motors are low efficiency and low power factor motors. This low efficiency and low power factor undesirably requure an oversized umbilical connection and variable frequency converter on the topside mm order to provide a large amount of
VAR power to the subsea motor. Both, the oversized umbilical connection and variable frequency converter undesirably increase the cost to the subsea pumping system.
[0004] I would be both advantageous and beneficial to provide a subsea pumping system that overcomes the problems generally associated with subsea pumping systems that employ induction motors. The subsea pumping system should have an overall efficiency that is greater than known subsea pumping svstems uitlizing induction motors, such that the subsea pumping system could function using a low power rating umbilical. Ht would be further advantageous if the subsea pumping system had a higher power factor than known subsea pumping systems utilizing induction motors, such that the subsea pumping system could function using a tow power rating topside variable frequency converter.
{0005] Briefly, in accordance with one embodiment, a subsea pump drive motor comprises a stator, a rotor comprising a plurality of permanent magnet pole meces, and a non-magnetic can configured to affix the pole pieces to the rotor.
[0006] According to another embodiment, a subsea pump drive sysiem comprises a permanent magnet subsea pump drive motor having a rotor configured with a plurality of permanent magnet pole pieces, the rotor and plurality of pole pieces disposed within a non-magnetic can configured to prevent corrosion of the rotor and plurality of pole pieces. {0007 According to vet another embodiment, a method of controlling a subsea pump comprises: providing a permanent magnet (PM) subsea pump drive motor; and controlling the PM drive motor such that the PM drive motor drives a subsea pump in response fo variable frequency converter signals received by the PM drive motor.
[06008] These and olher features, aspects, and advantages of the present vention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
[0009] Figure 1 illustrates a permanent magnet motor subsea puny drive according to one embodiment of the invention:
[0010] Figure 2 idlustrates the permanent niagnet motor subsea pump drive depicted in Figure 1, but that does nol have a wireless transmitter such as depicted mn
Figure 1; {0011 Figure 3 illustrates in more detail, the rotor portion of the permanent magnet motor depicted in Figures | and 2, according to one embodiment; {0012} Figure 4 1s a cross-sectional view of the permanent magnet motor depicted in Figures 1 and 2, according to ong embodiment: {0013] Figure 5 illustrates a permanent magnet mofor subsea pump drive according to another eyabodiment of the vention; and {0014} Figure ¢ the permanent magnet molor subsea pump drive depicted in
Figure 3, bot thal does not have a wireless transmitter such as depicted in Figure §.
[0015] While the above-denmtified drawing figures set forth aliernative embodiments, other embodiments of the present invention are alse contemplated, as noted in the discussion. In all cases, this disclosure presents Hustrated embodiments of the present invention by wav of representation and not {imitation. Numerous other modifications and embodiments can be devised by those skilled in the art which fall within the scope and spirit of the principles of this invention.
[0016] Figure 1 lustrates a permanent niagnet motor subsea pump drive 10 according to one embodiment of the vention. Subsea pump drive 10 incledes a permanent magnet motor 12 comprising a stator 14 and a rotor 16. Windings 29 are disposed in stator slots. The rotor 16 comprises a plurality of permanent magnet (PM) poles described herein below with reference to Figures 3 and 4. The rotor 16 also includes a non-magnetic can configured to fix the permanent magnets to the rotor 16, also described further herein below with reference to Figure 3. {17 Four sets of blades 22 are disposed on the rotor shaft 24. These blades 22 are configured to pump cooling fwd 26 Jowing through a motor sealing can 28 that encapsulates both the stator 14 and the rotor 16 according to one aspect of the mvention iflustrated in Figures 3 and 6, where both the stator 14 and the rotor 16 are canned Lor corrosion protection when processed fwd is used for cooling. The cooling fluid 26 works to provide cooling of the stator 14, rotor 16. and the associated bearings. In another embodiment lustrated in Figures | and 2, the stator 14 is not canned, and the machine cavity 30 is filled with a clean cooling fluid having a suitable thermal conductivity while also possessing workable electrical insulation characteristics. A heat exchanger 34 operates fo transfer heat from the motor 12 to outside seawater.
[0018] A rotor 16 position signal generated via an encoder 32 is transferred to a vanable frequency converter (VED) 33 via a wireless signal Uransmitier 36 according to one embodiment. In another embodiment depicted in Figure 2, the rotor position signal is transferred to a VED via a suitable conumunication cable (40)
[0019] The encoder 32 is connected to one end of rotor shafl 24 to detector rotor position for proper speadftorque control of the permanent magnet motor 12.
Traditional control approaches wilizing comnuunication cables are difficult to employ when the VFD 35 1s far away from the motor 12 due to signal attenuation along cables between the motor 12 and the VFD 35. Further, traditional sensorless control approaches alse face challenges due to difficulties associated with accurate measurement of motor terminal voltages through such long distances. {0020} The foregoing challenges associated with tradional control approaches utilizing communication cables are overcome using a wireless signal ranspufter 36, discussed herein above. The rotor position signals are sent to the wireless signal transnutter 36, which then transmits the rotor position signals 0 a topside controller VED 35 that is used to drive the PM motor 12,
[0021] Figure 2 illustrates the permanent magnet motor subsea pump drive depicted in Figure 1. but that does not have a wireless transmitter such as depicted in
Figure {. The rotor position signal is transferred through suttable communication wires 40. This topology ts especially useful when a long cable is not required. i.e. a subsea VFD 38 is emploved and is located in close proximity to the PM motor 12.
[0022] The end of the rotor shaft 24 opposite the end connecled to the encoder 32 1s connected to a sobsea pump 40, such as a multiphase pump. There is a seal 42 between the motor 12 and pump 40 to block motor cooling fluid 26 from Mowing into the pump 40. The fluid pressure mside the motor 12 is normally maintained higher than the fluid pressure mside the pump 40 via a pressunizer typically located subsea beside the motor 12, such as described below with reference to Figures 5 and 6, to prevent any processed thud 44 Dowing nto the motor side from the pump side. Any motor cooling fluid leakage that may pass {rom the motor side into the pump side that occurs during motor-pump set rotation 1s replenished via a {opside flaid tank 46 that is connected to the subsea motor 12 through an umbilical supply lime 48 lo provide cooling fluid as needed. {0023] Figure 3 illustrates in more detail, the rotor 16 portion of the permanent magnet motor 12 depicted in Figures 1 and 2. according to one embodiment. A nonmagnetic can S50 that is constructed from a switable nonmagnetic material such as, without limitation, mconel or alununom, is configured to attach a plurality of magnets 32 to the rotor core or back tron portion 34 of the rotor 16, and to protect each magnet from corrosion. The back ron portion 54 1s constructed from a suitable ferronmagnetic nualerial,
[0024] Figure 4 1s a cross-sectional view of the permanent magnet motor 12 depicted in Figures 1 and 2, according to one embodiment. One portion of the motor shaft 24 15 encapsulated via the rotor core 34. The permanent magnets 32 having north and south poles, are attached to the rotor core 34 via the rotor can 30. Stator laminations 56 having slots 38 surround the rotor can 30.
[0025] Figure 5 illustrates a permanent magnet motor subsea pump drive 100 according to another embodiment of the invention. Pomp drive 100 includes a permanent magnet motor 102 that is cooled using the had 44 processed by the subsea pump 40. Subsea pump drive 100 does not require a topside storage tank or associated umbilical cooling uid supply line such as emploved by pump drive 10 described above with reference fo Figures | and 2.
[0026] A pressasizer 104 is employed lo maintain a positive pressure [rom the motor 12 to the subsea pump 40 under all conditions. An optional bquid storage tank 106 can be used to store processed fluid 44 for motor cooling purposes when the processed (uid is purely gas. {0027} The stator 14 is also encapsulated via a can 108 to prevent any process flaid 44 or gas from entering the stator 14 portion of the permanent magnet molor 102. Ths stator can TOR is Oiled with a clean cooling flutd 26, such as a suitable oil, to cool the stator 14. A heat exchanger 34 can be emploved to exchange heat from the motor 102 to outside seawater.
[0028] Subsea pump drive 100 also employs an encoder 32 that is connected to one end of rotor shaft 24 to detector rotor position for proper speedforque control of the permanent magnet motor 102. A rotor 16 position signal generated via the encoder 32 is transferred to a vanable frequency converter (VED) 33 via a wireless signal transmitter 36 according to one embodiment. In another embodiment depicted in Figure 6. the rotor position signal is transferred to a VFD 38 via a suitable conumunication cable (40) and does not have a wireless transmitter such as depicted in
Figure 5.
[0029] In summary explanation, a subsea pump drive employs a permanent magnet (PM) motor to drive a subsea pump. The PM motor rotor in one embodiment is canned with a non-magnetic material such as weonel, that can provide a desired level of corrosion protection. The PM motor provides a subsea pump drive that is smaller and more efficient, having a high power factor than a subsea pump drive uiifizing a conventional mduction motor. The PM motor subsea pump drive ehounates the necessity Tor a topside storage tank and associated fluid transfer lines when the motor rotor 1s cooled with processed fluid.
[0030] The PM subsea pump drive motor achieves iis high efficiency due to the permanent magnetic flux on the rotor hnking the stator so that the PM motor can achieve higher efficiency due to absence of rotor current. {0031} The PM subsea pump drive motor further has an increased power factor due to the absence of exciting current. {0032} The PM subsea pump drive motor employs lower power umbilical features due to the aforesaid high power factor and high motor efficiency. {0033] The PM subsea pump drive motor emplovs a lower power topside variable frequency converter due to the aforesaid high power factor and high motor efficiency.
[0034] While only certain features of the invention have been illustrated and described herein, many modifications and changes will ccewr to those skilled in the art. tis, therefore, to be understood that the appended claims are inlended to cover all such modifications and changes as {all within the true spint of the invention.
Claims (1)
- CLAIMS:I. A subsea pump drive motor comprising: a staan; a rotor comprising a plurality of permanent magnet pole pleces; and a non-magnetic can configured to affix the pole pieces to the rotor.2. The subsea pump drive motor according to claim 1, further comprising a stator can enveloping the stator and configured to receive a stator cooling fhad3. The subsea pump drive motor according to clam 2, further comprising a heat exchanger configured to transfer heat from the stator cooling fluid to seawater surrounding the pump drive motor.4. The subsea pump drive motor according to claim 1, wherein the motor is configured to be cooled via a fluid processed via a subsea pump.5. The subsea pump drive molor according to claim 1, wherein motor 1s configured to be cooled via a desired cooling fluid baving desired thermal transfer and electrical insulation characteristics.6. The subsea pump drive motor according to claim §, further comprising a heat exchanger configured to transfer heat from the motor cooling fluid to seawater surrounding the pump drive motor.7. The subsea pump drive motor according fo claim 1, further comprising a rotor shalt seal configured to prevent motor cooling fwd from exiting the subsea pump drive motor.8. The subsea pump drive motor according to claim 1, further compnising an encoder affixed to one end of the rotor shafl to detect the position of the rotor.9 The subsea pump drive motor according to claim 8, further comprising a wireless signal transmitter configered {0 receive rotor position signals generated via the encoder and transmit the signals to a desired variable frequency converler controller. 1}, A subsea pump drive svstem comprising a permanent magnet (PM) subsea pump drive motor having a rotor configured with a plurality of permanent magnet pole pieces, the rotor and phuality of pole pieces disposed within a non- magnetic can configured to prevent corrosion of the rotor and plurality of pole pieces.11. The subsea purap dnve system according to claim 10, wherein the PM drive motor further comprises a stator can enveloping the stator and configured to receive a stator cooling Quid.12. The subsea pump drive svstem according to claim 11, further comprising a heat exchanger configured to transfer heat from the stator cooling fwd to seawater surrounding the PM pump drive motor.13. The subsea pump drive system according to claim 10, wherein the PM motor is further configured to be cooled via a fluid processed via a subsea pump.14. The subsea punip drive system according to claim 10, wherein the PM motor is further configured to be cooled via a cooling fluid having desired thermal transfer and electrical wsulation characteristics.15. The subsea pump drive system according to claim 14, further corpprising a heat exchanger configured to transfer heat from the motor cooling fluid to seawater surrounding the PM pump drive motor,16. The subsea pump drive system according to claim 10, further comprising a rolor shall seal configured to prevent PM motor cooling fwd from exiting the subsea pump drive PM motor.17. The subsea pump drive system according to claim {0, further comprising an encoder affixed to one end of the rotor shaft to detect the position of the rotor.15. The subsea pump drive systems according to claim 17, further comprising a wireless signal transmitter configured to receive rotor position signals generated via the encoder and {ransmit the signals to a desired variable frequency converter controller. 14, A method of controlling a subsea pump, the method comprising: providing a permanent magnet {PM) subsea pump drive motor: and driving a subsea pump via the PM drive motor.24. The method according to claim 19, wherein providing a PM subsea pump drive motor comprises providing an encoder affixed to one end of the PM subsea pump drive motor rotor shaft to detect the position of the PM motor rotor.21. The method according to claim 20, further comprising. providing a wireless signal transmitter configured to receive rotor position signals generated via the encoder and fransmit the signals to a desired variable frequency converter controller; and controlling speed and torque characteristics of the PM motor in response to the rotor position signals generated via the encoder.22. The method according to claim 19, wherein providing a PM subsea pump drive motor comprises providing a rotor configured with a pluraluy of permanent magnet pole pieces, the rotor and plurality of pole pieces disposed within a non~magnetic can configured to prevent corrosion of the rotor and plurality of pole pieces.23. The method according to claim 22, wherein providing a PM subsea pump drive motor further comprises providing a stator and a stator can enveloping the stator and configured to receive a stator cooling fluid.24. The method according to claim 23, further comprising: providing a heat exchanger; and ransferrmyg heat from the stator cooling uid to the seawater surrounding the pump drive motor via the heat exchanger.25. The method according to claim 19, further comprising cooling the PM drive motor via a fluid processed via the subsea pump while the PM drive niolor is driving the subsea pump.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/US2009/053366 WO2011019334A1 (en) | 2009-08-11 | 2009-08-11 | Permanent magnet motor for subsea pump drive |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| SG178355A1 true SG178355A1 (en) | 2012-03-29 |
Family
ID=41828303
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| SG2012009379A SG178355A1 (en) | 2009-08-11 | 2009-08-11 | Permanent magnet motor for subsea pump drive |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP2464875A1 (en) |
| CN (1) | CN102472286A (en) |
| SG (1) | SG178355A1 (en) |
| WO (1) | WO2011019334A1 (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NO20110786A1 (en) | 2011-05-31 | 2012-12-03 | Fmc Kongsberg Subsea As | Subsea compressor directly driven by a permanent magnet motor with a stator and rotor immersed in liquid |
| CN103187829A (en) * | 2011-12-30 | 2013-07-03 | 哈米尔顿森德斯特兰德空间系统国际有限公司 | Cooling of permanent magnet motor |
| DE102013201778A1 (en) * | 2013-02-04 | 2014-08-07 | Siemens Aktiengesellschaft | Electric machine with stand direct cooling |
| WO2015178887A1 (en) * | 2014-05-19 | 2015-11-26 | Ge Oil Gas Esp, Inc. | Optimized cooling for electric motor in artificial lift |
| AU2015330672B2 (en) * | 2014-10-09 | 2018-10-04 | Direct Drive Systems, Inc. | Permanent magnet motor control for electric subsea pump |
| DE102018214555B4 (en) * | 2018-08-28 | 2022-09-08 | Hawe Hydraulik Se | Modular motor pump unit |
| EP3763943B1 (en) | 2019-07-10 | 2024-09-04 | Grundfos Holding A/S | Method for manufacturing a can |
| US11808268B2 (en) | 2020-10-19 | 2023-11-07 | Milwaukee Electric Tool Corporation | Stick pump assembly |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2556435A (en) * | 1950-04-27 | 1951-06-12 | Layne & Bowler Inc | Means for cooling lubricating oil in submerged motors |
| DE1030441B (en) * | 1956-04-07 | 1958-05-22 | Ritz & Schweizer Geb | Liquid cooling of the electric drive motor of a submersible motor pump |
| IT8420754A0 (en) * | 1984-05-02 | 1984-05-02 | Pompe Ing Calella S P A | COMPACT AGGREGATE FOR FULLY SUBMERGED CENTRIFUGAL PUMP/ELECTRIC MOTOR FOR PUMPING AGGRESSIVE LIQUIDS AND/OR CONTAINING SOLID SUBSTANCES. |
| US5795135A (en) * | 1995-12-05 | 1998-08-18 | Westinghouse Electric Corp. | Sub-sea pumping system and an associated method including pressure compensating arrangement for cooling and lubricating fluid |
| GB0314553D0 (en) * | 2003-06-21 | 2003-07-30 | Weatherford Lamb | Electric submersible pumps |
| US7508101B2 (en) * | 2006-02-24 | 2009-03-24 | General Electric Company | Methods and apparatus for using an electrical machine to transport fluids through a pipeline |
| WO2007110271A1 (en) * | 2006-03-24 | 2007-10-04 | Siemens Aktiengesellschaft | Compressor unit and use of a cooling medium |
| US7709988B2 (en) * | 2006-04-07 | 2010-05-04 | General Electric Company | Methods and apparatus for using an electrical machine to transport fluids through a pipeline |
-
2009
- 2009-08-11 CN CN2009801609461A patent/CN102472286A/en active Pending
- 2009-08-11 SG SG2012009379A patent/SG178355A1/en unknown
- 2009-08-11 WO PCT/US2009/053366 patent/WO2011019334A1/en active Application Filing
- 2009-08-11 EP EP09791362A patent/EP2464875A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| CN102472286A (en) | 2012-05-23 |
| WO2011019334A1 (en) | 2011-02-17 |
| EP2464875A1 (en) | 2012-06-20 |
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