WO2002025115A1 - Multi-stage screw compressor - Google Patents
Multi-stage screw compressor Download PDFInfo
- Publication number
- WO2002025115A1 WO2002025115A1 PCT/GB2001/004278 GB0104278W WO0225115A1 WO 2002025115 A1 WO2002025115 A1 WO 2002025115A1 GB 0104278 W GB0104278 W GB 0104278W WO 0225115 A1 WO0225115 A1 WO 0225115A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- stage
- compressor
- drive means
- screw compressor
- compression
- Prior art date
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
- F04C28/08—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by varying the rotational speed
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/08—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
- F04C18/12—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
- F04C18/14—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons
- F04C18/16—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
- F04C23/001—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids of similar working principle
Definitions
- OAPI patent BF, BJ CF, CG, CI, CM, GA, GN, GQ, GW, a patent (Rule 4 17(H)) for the following designations AE, ML, MR, NE, SN TD, TG) AG, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, BZ, CA, CH, — of inventors hip (Rule 4 17( ⁇ v)) for US only CN CO, CR, CU, CZ, DE, DK, DM, DZ, EC, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, KG,
- the invention relates to improvements in the drive of a multi-stage screw compressor using independent electric motors with electronic speed control.
- a set of compressor stages may be used, running at different speeds, to give a range of output air flows.
- the speed of all the stages must be increased. Due to the difference in performance characteristics of each stage, the increase in speed of each stage will not be the same.
- the relative speed of the stages may need to be altered depending on the desired final stage delivery pressure or overall pressure ratio.
- the basic parameter that determines the relative speed of the stages is the work done in each stage. To obtain the best efficiency, the work has to be balanced equally in each stage.
- inlet throttling can only be used over a very narrow range of speeds as it effectively increases the pressure ratio across the machine. This again leads to overheating. For this reason multi-stage compressors are usually controlled by total closure of the inlet by a control valve. This provides very coarse pressure or flow control with poor efficiency. Varying the speed of the drive motor has been used to control some machines to improve efficiency at part load. With a fixed ratio of speeds between the stages this leads to an imbalance of work between the stages which may limit the control range. It is an object of the present invention to overcome these disadvantages.
- multi-stage screw compressor comprising at least two stages of compression, each compressor stage comprising a pair of rotors driven to effect gas compression; each compression stage being provided with independent variable speed drive means; and a control unit for controlling the speeds of the independent drive means, the control unit comprising processing means for processing signals generated by a plurality of devices monitoring operating parameters of the compressor, and adjusting the speeds of the drive means to provide a required gas flow delivery rate and pressure, wherein at least one of said monitoring devices monitors the torque and at least one of said monitoring devices monitors the speed of each drive means.
- Fig. 1 is a schematic representation of the operation of a typical prior art screw compressor
- Fig. 2 is a schematic representation of a screw compressor according to the present invention.
- FIG. 1 A typical prior art two-stage compressor 5 is shown in Fig. 1. Although a two-stage, oil-free machine is shown for clarity, the principles are the same where more stages are involved or where the stages have oil or water injection.
- Each of the two compressor stages 10, 11 consists of a pair of contra-rotating, helically cut fluted rotors supported at each end in rolling bearings in a rigid casing. Each casing is attached to a single gearbox 12.
- the drive motor 13 is coupled to the input gear in the gearbox 12, which transfers drive to the stages 10, 11 via a pinion on the shafts 12a, 12b - 4 -
- Air is drawn through an air filter 14 and inlet control valve 15 into the inlet port of the first stage 10 where it is partially compressed.
- the partially compressed air from the first stage 10 passes to an intercooler 16, where its temperature is reduced before the air is passed to the inlet of the second stage 11 for further compression.
- On leaving the second (or final) stage 11 the fully compressed air passes via a check valve 17 to an aftercooler 18 for further cooling, after which it is delivered to the user via air delivery outlet 19.
- FIG. 2 shows a compressor 30 according to the present invention.
- the essential operation is as described above, but differs from the prior art compressor 5 in that independent, variable speed motors 31, 32 drive each stage 10, 11 of the compressor 30 independently, with no mechanical link between the individual motor driven stages 10, 11.
- the characteristics of the motors 31, 32 are matched to the corresponding compressor stages 10, 11.
- the speed of the motors 31, 32 is controlled by an electronic controller 33.
- the basic control parameter is the required final air delivery pressure or delivery air flow rate.
- the speed at which each of the stages 10, 11 is driven is increased to give a greater air flow or is reduced to give a lesser air flow.
- the maximum rotary speeds are limited to predetermined levels based on mechanical considerations. The minimum speeds are either pre-determined or are determined by measuring the delivery temperatures of each stage 10, 11. As the speed of the rotors in any stage slows down, the stage becomes less efficient 5 -
- the speeds of the individual compressor stages 10, 11 are varied to compensate for a variety of factors. These factors include altitude, barometric pressure, ambient temperature and coolant temperature, blocking of filters and wear. Manufacturing variations in the compressor stages 10, 11 are also compensated for.
- This control is achieved by continuously measuring air delivery pressures and temperatures from each stage 10, 11, as well as the input torque and speed to each stage 10, 11. Appropriate measuring devices are used to measure these parameters and transmit signals to the electronic controller 33.
- the motors 31, 32 may have feedback loops directly to the controller 33.
- the controller 33 processes the signals and sets the speed of the stages 10, 11 to achieve the desired delivery air flow and pressure. Then, using the measurements previously described, the controller 33 makes small adjustments to the stage speeds to minimise power consumption, balance the work evenly between the various stages and maintain safe operating temperatures.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Applications Or Details Of Rotary Compressors (AREA)
- Electromagnetic Pumps, Or The Like (AREA)
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP01969980A EP1387961B1 (en) | 2000-09-25 | 2001-09-25 | Multi-stage screw compressor |
DE60117821T DE60117821T2 (en) | 2000-09-25 | 2001-09-25 | MULTI-STAGE SCREW COMPRESSOR |
US10/380,955 US20040101411A1 (en) | 2000-09-25 | 2001-09-25 | Multi-stage screw compressor |
AU2001290100A AU2001290100A1 (en) | 2000-09-25 | 2001-09-25 | Multi-stage screw compressor |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0023456.7 | 2000-09-25 | ||
GB0023456A GB2367332B (en) | 2000-09-25 | 2000-09-25 | Improvements in multi-stage screw compressor drive arrangements |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2002025115A1 true WO2002025115A1 (en) | 2002-03-28 |
Family
ID=9900069
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB2001/004278 WO2002025115A1 (en) | 2000-09-25 | 2001-09-25 | Multi-stage screw compressor |
Country Status (8)
Country | Link |
---|---|
US (1) | US20040101411A1 (en) |
EP (1) | EP1387961B1 (en) |
AT (1) | ATE319932T1 (en) |
AU (1) | AU2001290100A1 (en) |
DE (1) | DE60117821T2 (en) |
ES (1) | ES2260285T3 (en) |
GB (1) | GB2367332B (en) |
WO (1) | WO2002025115A1 (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7481627B2 (en) | 2004-08-30 | 2009-01-27 | Mat Industries Llc | Air compressor tools that communicate with an air compressor |
DE102008021102A1 (en) * | 2008-04-28 | 2009-10-29 | Siemens Aktiengesellschaft | Efficiency monitoring of a compressor |
BE1018096A3 (en) * | 2008-04-14 | 2010-05-04 | Atlas Copco Airpower Nv | Multi-stage compressor controlling method for compressed air system e.g. absorption dryer, involves controlling exhaust temperature of one compressor element or intermediate pressure between two linked compressor elements |
US7789102B2 (en) | 2004-08-30 | 2010-09-07 | Mat Industries Llc | Air compressor having a pneumatic controller for controlling output air pressure |
EP1975415A3 (en) * | 2007-03-30 | 2012-05-23 | Anest Iwata Corporation | Rotary compressor unit and method of controlling operation thereof |
EP3018351A3 (en) * | 2014-11-05 | 2016-08-31 | Mitsubishi Heavy Industries, Ltd. | Two-stage-compression refrigerating cycle apparatus, and device and method for controlling the apparatus |
EP3312423A1 (en) * | 2016-10-24 | 2018-04-25 | Hamilton Sundstrand Corporation | Variable speed multi-stage pump |
WO2020065505A1 (en) * | 2018-09-25 | 2020-04-02 | Atlas Copco Airpower, Naamloze Vennootschap | Oil-injected multistage compressor device and method for controlling such a compressor device |
US11519412B2 (en) | 2018-09-25 | 2022-12-06 | Atlas Copco Airpower. Naamloze Vennootschap | Oil-injected multistage compressor device and method for controlling a compressor device |
Families Citing this family (14)
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GB2452287B (en) * | 2007-08-29 | 2012-03-07 | Gardner Denver Gmbh | Improvements in compressors control |
US10941770B2 (en) | 2010-07-20 | 2021-03-09 | Trane International Inc. | Variable capacity screw compressor and method |
TWI397634B (en) * | 2010-12-06 | 2013-06-01 | China Steel Corp | On-line monitor method of multi-stage compressor |
US10443603B2 (en) | 2012-10-03 | 2019-10-15 | Praxair Technology, Inc. | Method for compressing an incoming feed air stream in a cryogenic air separation plant |
US10385861B2 (en) | 2012-10-03 | 2019-08-20 | Praxair Technology, Inc. | Method for compressing an incoming feed air stream in a cryogenic air separation plant |
US20160053764A1 (en) * | 2012-10-03 | 2016-02-25 | Ahmed F. Abdelwahab | Method for controlling the compression of an incoming feed air stream to a cryogenic air separation plant |
DE102014107126A1 (en) * | 2014-05-20 | 2015-11-26 | Harald Wenzel | Multi-stage compressor system for generating a compressed gas |
JP6491982B2 (en) * | 2015-08-28 | 2019-03-27 | 株式会社神戸製鋼所 | Two-stage screw compressor and operating method thereof |
DE102017107601B4 (en) | 2017-04-10 | 2019-11-07 | Gardner Denver Deutschland Gmbh | Method for controlling a screw compressor |
DE102017107599A1 (en) | 2017-04-10 | 2018-10-11 | Gardner Denver Deutschland Gmbh | Pulsation silencer for compressors |
DE102017107602B3 (en) | 2017-04-10 | 2018-09-20 | Gardner Denver Deutschland Gmbh | Compressor system with internal air-water cooling |
DE102019102387A1 (en) | 2019-01-30 | 2020-07-30 | Gardner Denver Deutschland Gmbh | Cooling arrangement and method for cooling an at least two-stage compressed air generator |
DE102020103384A1 (en) | 2020-02-11 | 2021-08-12 | Gardner Denver Deutschland Gmbh | Screw compressor with rotors mounted on one side |
CN115126695A (en) * | 2021-03-25 | 2022-09-30 | 开利公司 | Two-stage screw compressor and air conditioning system |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0570114A1 (en) * | 1992-05-12 | 1993-11-18 | Ingersoll-Rand Company | Control system for prime driver of compressor and method |
JPH07158576A (en) * | 1993-12-03 | 1995-06-20 | Kobe Steel Ltd | Two-stage type oil free screw compressor |
EP0658730A1 (en) * | 1993-12-14 | 1995-06-21 | Carrier Corporation | Economizer control for two-stage compressor systems |
WO2001031202A1 (en) * | 1999-10-26 | 2001-05-03 | Atlas Copco Airpower, Naamloze Vennootschap | Multistage compressor unit and method for regulating such multistage compressor unit |
DE10003869A1 (en) * | 2000-01-28 | 2001-08-16 | Aerzener Maschf Gmbh | Compressing fluid conveying mediums using at least two compressor units so that the outlet of the respective series connected compressor unit is in communication |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2909675C3 (en) * | 1979-03-12 | 1981-11-19 | M.A.N. Maschinenfabrik Augsburg-Nürnberg AG, 4200 Oberhausen | Process for condensate-free intermediate cooling of compressed gases |
DE3032002C2 (en) * | 1980-08-25 | 1986-01-16 | M.A.N. Maschinenfabrik Augsburg-Nürnberg AG, 4200 Oberhausen | Device for regulating the flow rate of a single or multi-stage compressor arrangement, in particular for screw compressors |
JPS5885062A (en) * | 1981-11-16 | 1983-05-21 | 株式会社デンソー | Air conditioner for automobile |
US4787211A (en) * | 1984-07-30 | 1988-11-29 | Copeland Corporation | Refrigeration system |
EP0209499A3 (en) * | 1985-06-10 | 1987-08-12 | Institut Cerac S.A. | A compressor plant |
JPS62243982A (en) * | 1986-04-14 | 1987-10-24 | Hitachi Ltd | 2-stage vacuum pump and operating method thereof |
DE4318707A1 (en) * | 1993-06-04 | 1994-12-08 | Sihi Gmbh & Co Kg | Displacement machine with electronic motor synchronization |
US5797729A (en) * | 1996-02-16 | 1998-08-25 | Aspen Systems, Inc. | Controlling multiple variable speed compressors |
JPH1082391A (en) * | 1996-07-19 | 1998-03-31 | Ishikawajima Harima Heavy Ind Co Ltd | Control device of two-stage screw compressor |
KR20000068244A (en) * | 1996-08-19 | 2000-11-25 | 이노우에 노리유끼 | Synchronous motor driving method. compressor driving method, device for the methods, and brushless dc motor driving device |
JP3767052B2 (en) * | 1996-11-30 | 2006-04-19 | アイシン精機株式会社 | Multistage vacuum pump |
JPH1137053A (en) * | 1997-07-23 | 1999-02-09 | Ishikawajima Harima Heavy Ind Co Ltd | Control method for inverter drive multistage compressor |
-
2000
- 2000-09-25 GB GB0023456A patent/GB2367332B/en not_active Expired - Fee Related
-
2001
- 2001-09-25 US US10/380,955 patent/US20040101411A1/en not_active Abandoned
- 2001-09-25 AU AU2001290100A patent/AU2001290100A1/en not_active Abandoned
- 2001-09-25 ES ES01969980T patent/ES2260285T3/en not_active Expired - Lifetime
- 2001-09-25 WO PCT/GB2001/004278 patent/WO2002025115A1/en active IP Right Grant
- 2001-09-25 EP EP01969980A patent/EP1387961B1/en not_active Expired - Lifetime
- 2001-09-25 AT AT01969980T patent/ATE319932T1/en not_active IP Right Cessation
- 2001-09-25 DE DE60117821T patent/DE60117821T2/en not_active Expired - Fee Related
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0570114A1 (en) * | 1992-05-12 | 1993-11-18 | Ingersoll-Rand Company | Control system for prime driver of compressor and method |
JPH07158576A (en) * | 1993-12-03 | 1995-06-20 | Kobe Steel Ltd | Two-stage type oil free screw compressor |
EP0658730A1 (en) * | 1993-12-14 | 1995-06-21 | Carrier Corporation | Economizer control for two-stage compressor systems |
WO2001031202A1 (en) * | 1999-10-26 | 2001-05-03 | Atlas Copco Airpower, Naamloze Vennootschap | Multistage compressor unit and method for regulating such multistage compressor unit |
DE10003869A1 (en) * | 2000-01-28 | 2001-08-16 | Aerzener Maschf Gmbh | Compressing fluid conveying mediums using at least two compressor units so that the outlet of the respective series connected compressor unit is in communication |
Non-Patent Citations (1)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 1995, no. 09 31 October 1995 (1995-10-31) * |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7481627B2 (en) | 2004-08-30 | 2009-01-27 | Mat Industries Llc | Air compressor tools that communicate with an air compressor |
US7789102B2 (en) | 2004-08-30 | 2010-09-07 | Mat Industries Llc | Air compressor having a pneumatic controller for controlling output air pressure |
EP1975415A3 (en) * | 2007-03-30 | 2012-05-23 | Anest Iwata Corporation | Rotary compressor unit and method of controlling operation thereof |
BE1018096A3 (en) * | 2008-04-14 | 2010-05-04 | Atlas Copco Airpower Nv | Multi-stage compressor controlling method for compressed air system e.g. absorption dryer, involves controlling exhaust temperature of one compressor element or intermediate pressure between two linked compressor elements |
DE102008021102A1 (en) * | 2008-04-28 | 2009-10-29 | Siemens Aktiengesellschaft | Efficiency monitoring of a compressor |
CN102027348B (en) * | 2008-04-28 | 2015-05-20 | 西门子公司 | Efficiency monitoring of a compressor |
EP3018351A3 (en) * | 2014-11-05 | 2016-08-31 | Mitsubishi Heavy Industries, Ltd. | Two-stage-compression refrigerating cycle apparatus, and device and method for controlling the apparatus |
EP3312423A1 (en) * | 2016-10-24 | 2018-04-25 | Hamilton Sundstrand Corporation | Variable speed multi-stage pump |
US10428816B2 (en) | 2016-10-24 | 2019-10-01 | Hamilton Sundstrand Corporation | Variable speed multi-stage pump |
WO2020065505A1 (en) * | 2018-09-25 | 2020-04-02 | Atlas Copco Airpower, Naamloze Vennootschap | Oil-injected multistage compressor device and method for controlling such a compressor device |
BE1026652B1 (en) * | 2018-09-25 | 2020-04-28 | Atlas Copco Airpower Nv | Oil-injected multi-stage compressor device and method for controlling such a compressor device |
US11371507B2 (en) | 2018-09-25 | 2022-06-28 | Atlas Copco Airpower, Naamloze Vennootschap | Oil-injected multistage compressor device and method for controlling such a compressor device |
US11519412B2 (en) | 2018-09-25 | 2022-12-06 | Atlas Copco Airpower. Naamloze Vennootschap | Oil-injected multistage compressor device and method for controlling a compressor device |
Also Published As
Publication number | Publication date |
---|---|
DE60117821T2 (en) | 2006-11-02 |
US20040101411A1 (en) | 2004-05-27 |
AU2001290100A1 (en) | 2002-04-02 |
GB2367332B (en) | 2003-12-03 |
DE60117821D1 (en) | 2006-05-04 |
EP1387961B1 (en) | 2006-03-08 |
GB0023456D0 (en) | 2000-11-08 |
ES2260285T3 (en) | 2006-11-01 |
GB2367332A (en) | 2002-04-03 |
ATE319932T1 (en) | 2006-03-15 |
EP1387961A1 (en) | 2004-02-11 |
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