EP0223208B1 - Procédé et dispositif de réglage de turbocompresseurs - Google Patents

Procédé et dispositif de réglage de turbocompresseurs Download PDF

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Publication number
EP0223208B1
EP0223208B1 EP86115792A EP86115792A EP0223208B1 EP 0223208 B1 EP0223208 B1 EP 0223208B1 EP 86115792 A EP86115792 A EP 86115792A EP 86115792 A EP86115792 A EP 86115792A EP 0223208 B1 EP0223208 B1 EP 0223208B1
Authority
EP
European Patent Office
Prior art keywords
blow
controller
variable
curve
reference variable
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP86115792A
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German (de)
English (en)
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EP0223208A3 (en
EP0223208A2 (fr
Inventor
Wilfried Dipl.-Ing. Blotenberg
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
MAN Gutehoffnungshutte GmbH
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MAN Gutehoffnungshutte GmbH
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Application filed by MAN Gutehoffnungshutte GmbH filed Critical MAN Gutehoffnungshutte GmbH
Publication of EP0223208A2 publication Critical patent/EP0223208A2/fr
Publication of EP0223208A3 publication Critical patent/EP0223208A3/de
Application granted granted Critical
Publication of EP0223208B1 publication Critical patent/EP0223208B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
    • F04D27/02—Surge control
    • F04D27/0207—Surge control by bleeding, bypassing or recycling fluids

Definitions

  • the invention relates to a method for regulating turbo compressors for preventing pumping, of the type specified in the preamble of claim 1, and a device for carrying out the method
  • pumps are the intermittent or periodic backflow of the medium from the pressure to the suction side. This condition occurs e.g. if the final pressure or final pressure / suction pressure ratio and / or the throughput are too low.
  • a surge limit line can therefore be clearly defined in the map, which divides the map into the stable and unstable area.
  • the surge line is usually curved, i.e. it has different slopes in different areas of the map. In the frequently used map display with throughput and pressure as coordinates, for example, the surge line is flatter with increasing pressure. The same applies to other possible characteristic diagram representations with guide vane position, speed, head of the compressor or the like.
  • a blow-off line is defined at a safety distance parallel to the surge line, and when the current operating point approaches the blow-off line, a blow-off valve is opened more or less so that the actual value of a controlled variable, in particular the throughput, is based on the Blow-off line and the reference variable, especially the final pressure, do not exceed the setpoint.
  • a controlled variable in particular the throughput
  • the throughput serves as a reference variable for forming the setpoint and the final pressure is the controlled variable to be regulated to the setpoint.
  • the result of the curved course of the blow-off line is that a predetermined change in the command variable at different points on the blow-off line results in changes in the desired value for the controlled variable of different sizes. This affects the strengthening of the control loop to different degrees.
  • Pump limit controllers are safety controllers and are usually activated so that they work close to the stability limit in order to ensure the best possible compressor protection.
  • the position of the stability limit is very much influenced by the overall gain of the control loop. A high overall gain is most likely to lead to instability.
  • the gain factor of the actual controller is therefore set in such a way that, together with the gain resulting from the slope of the blow-off line, it leads to an overall gain within the stability limit.
  • the area of the blow-off line in which the highest gain is effective must be used. In other areas of the blow-off line, which may also include the most common arberite areas, the control loop is then not optimally adjusted.
  • the strongly curved course of the blow-off line therefore has the consequence that a surge limit controller with fixed control parameters is not optimally adjusted in wide working areas.
  • a method of the type mentioned is known from FR-A-2 352 970.
  • the gain of the controller can be changed as a function of the control difference, in such a way that the gain factor is increased when the control difference takes a negative value. This can ensure that the control loop reacts quickly when the current operating point crosses the blow-off line towards the surge limit line. Since the gain is only a function of the control difference, it is independent of the course of the blow-off line, and the different slope of the blow-off line in the map has a corresponding effect on the overall loop gain.
  • the object of the invention is to provide a method of the type mentioned at the outset and a device for carrying it out, with which an adaptation of the control behavior to the requirements in the different areas of the characteristic diagram is possible.
  • the invention is based on the basic idea of compensating for the effects of the slope of the curved blow-off line, which changes according to the command variable, on the overall gain of the control loop by a correspondingly opposite change in the gain factor of the controller, so that there is a largely constant overall gain of the control loop in the entire working range.
  • This basic principle can also be approximated by switching between two or a few different values of the gain factor of the controller.
  • the pressure in front of and behind a throttle orifice is measured in the suction port 1 of a compressor K by means of sensors 3.5, from which a transmitter 7 forms the actual value for the compressor throughput V on the suction side.
  • a sensor 9 detects the actual value of the final pressure P, which is entered into a computer 13 via a transmitter 11.
  • the computer 13 is connected to a memory 15 in which the course of the blow-off line A is stored in the compressor map given by P and V.
  • the computer 13 determines a setpoint for the through from the actual value of P and the blow-off line Set V.
  • a differential element 17 Actual and setpoint are compared in a differential element 17 and the difference is fed as an input signal to a controller 19, which can have a proportional-integral and / or differential behavior and whose Aussenassignal is a manipulated variable for a relief valve 21 branching off from the compressor outlet or for Return nozzle return blow valve delivers.
  • the steep lower course of the blow-off line A corresponds to a small gain and the flat upper course to a high gain. If, on the other hand, what is also known is reversed, the role of the command variable and the controlled variable and the throughput V is used as the command variable for determining a desired value of the final pressure P, the conditions are reversed and the gain is large and flat in the steep part of the blow-off line Part small.
  • the total gain of the control loop is the sum of the gain resulting from the slope of the blow-off line and the gain factor of the controller 19 plus the so-called system gain, i.e. the gain factors specified by the controlled system, in particular the compressor and the relief valve.
  • the gain factor in the controller 19 is therefore changed according to the invention.
  • the course of the slope S of the blow-off line A is also specified as a function in the memory 15.
  • the computer 13 determines the associated value of the slope of the blow-off line and generates a corresponding control signal which is fed to a control input of the controller 19 and there causes a corresponding change in the gain factor of the controller 19.
  • the computer 13 can also calculate its slope from the values of the blow-off line A belonging to different values of P.
  • the actual value of P is not supplied to a computer, but rather to a simple function generator 23, which permanently assigns a desired value for V to each actual value of P in accordance with a predetermined relationship corresponding to the blow-off line.
  • the actual value of P is fed to a second function generator 25, which permanently assigns a corresponding value for the slope of the blow-off line to each actual value of P, which is then fed as a control signal to controller 19 for controlling the amplification factor.
  • the actual value of P is likewise fed to the function generator 23 and also to a comparator 27 which compares the actual value of P with predetermined upper and lower limit values Pmax, P min. As long as the actual value of P is within this limit, the gain factor of the controller 19 remains unchanged. If P max is exceeded or Pmin is undershot, the gain factor of controller 19 is increased or decreased by a fixed, predetermined value. This corresponds to an approximation of the curved course of the blow-off line through three straight sections with different slopes, the middle straight section running between the limit values Pmin, Pmax. In an even simpler embodiment, which corresponds to an approximation of the blow-off line by only two straight sections, the gain factor is switched between two values depending on whether a single limit value is exceeded or not reached.
  • blow-off line in the memory 15 can also not be predetermined by a table of values but by a mathematical function.
  • a course of the blow-off line approximated by two or more straight line sections can be predetermined in the function generator 25.
  • the described mode of operation is not tied to the selected map display with the coordinates final pressure and volume flow, but can also be adapted to any other map display familiar to a person skilled in the art.

Claims (7)

1. Procédé pour réguler un turbocompresseur en évitant le pompage, dans lequel on détecte en continu les valeurs réelles d'une grandeur pilote, notamment de la pression de sortie, et d'une grandeur réglée, notamment du débit, qui définissent conjointement la position du point de fonctionnement dans le diagramme caractéristique du compresseur, on forme une valeur de consigne de la grandeur réglée à partir de la grandeur pilote et d'une ligne de purge prédéterminée dans le diagramme caractéristique, un signal de manoeuvre d'une soupape de purge étant produit par un régulateur en se référant à la valeur de consigne et à la valeur réelle, le facteur d'amplification du régulateur pouvant varier, caractérisé en ce qu'on fait varier le facteur d'amplification en fonction de la valeur réelle de la grandeur pilote, et en ce qu'on compense, au moins approximativement l'influence de la pente, variable en fonction de la grandeur pilote, de la ligne de purge sur l'amplification d'ensemble du circuit de réglage.
2. Procédé selon la revendication 1, caractérisé en ce qu'on commande le facteur d'amplification du régulateur de façon, au moins approximativement, inversement proportionnelle à la valeur de la pente de la ligne de purge correspondant à chaque valeur réelle de la grandeur pilote.
3. Procédé selon la revendication 1, caractérisé en ce que lors de l'approximation de la ligne de purge par des segments de droite, on commute le facteur d'amplification du régulateur entre des valeurs discrètes différentes quand la valeur réelle de la grandeur pilote franchit des valeurs limites prédéterminées vers le haut ou vers le bas.
4. Dispositif pour la mise en pratique du procédé selon l'une des revendications 1 à 3, comportant des capteurs pour la grandeur pilote et la grandeur réglée, un générateur de fonction sollicité par la grandeur pilote et contenant des données prédéterminées de la ligne de purge pour produire la valeur de consigne de la grandeur réglée, un élément sous- tracteur sollicité par la valeur réelle et la valeur de consigne de la grandeur réglée, un régulateur sollicité par le signal de sortie correspondant et une soupape de purge commandée par le régulateur, le régulateur (19) comportant une entrée de commande pour faire varier son facteur d'amplification, caractérisé en ce que le capteur (9) pour la grandeur pilote est raccordé à un générateur de signaux (13, 25, 27) muni de données prédéterminées et associées à la pente de la ligne de purge, et en ce que la sortie du générateur de signaux (13, 25, 27) est reliée à l'entrée de commande du régulateur (19).
5. Dispositif selon la revendication 4, caractérisé en ce que dans le générateur de signaux (13, 15) est prédéterminée une suite de valeurs donnant la pente de la ligne de purge en fonction de la grandeur pilote.
6. Dispositif selon la revendication 4, caractérisé en ce que des valeurs limites Pmax, Pmin de la grandeur pilote sont prédéterminées dans le générateur de signaux (27) et en ce que le générateur de signaux (27) produit des signaux de commutation pour faire varier par étages le facteur de réglage du régulateur (19) lors du franchissement des valeurs limites vers le haut et vers le bas.
7. Dispositif selon la revendication 1, caractérisé en ce que le facteur d'amplification du régulateur peut être commandé par branchement sélectif d'un amplificateur raccordé devant l'entrée du régulateur et en ce que le signal de sortie du générateur de signaux commande le branchement de l'amplificateur.
EP86115792A 1985-11-13 1986-11-13 Procédé et dispositif de réglage de turbocompresseurs Expired - Lifetime EP0223208B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853540285 DE3540285A1 (de) 1985-11-13 1985-11-13 Verfahren und einrichtung zum regeln von turbokompressoren
DE3540285 1985-11-13

Publications (3)

Publication Number Publication Date
EP0223208A2 EP0223208A2 (fr) 1987-05-27
EP0223208A3 EP0223208A3 (en) 1988-01-13
EP0223208B1 true EP0223208B1 (fr) 1990-10-03

Family

ID=6285904

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86115792A Expired - Lifetime EP0223208B1 (fr) 1985-11-13 1986-11-13 Procédé et dispositif de réglage de turbocompresseurs

Country Status (4)

Country Link
US (1) US4789298A (fr)
EP (1) EP0223208B1 (fr)
JP (1) JPS62113891A (fr)
DE (2) DE3540285A1 (fr)

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3805119A1 (de) * 1988-02-18 1989-08-31 Gutehoffnungshuette Man Verfahren und einrichtung zum regeln von turbokompressoren
DE3809070A1 (de) * 1988-03-18 1989-10-26 Gutehoffnungshuette Man Verfahren zum sicheren betreiben von turbo-kompressoren
DE3809881A1 (de) * 1988-03-24 1989-10-12 Gutehoffnungshuette Man Regelverfahren zur vermeidung des pumpens eines turbokompressors
DE3810717A1 (de) * 1988-03-30 1989-10-19 Gutehoffnungshuette Man Verfahren zur vermeidung des pumpens eines turboverdichters mittels abblaseregelung
DE3811230A1 (de) * 1988-04-02 1989-10-26 Gutehoffnungshuette Man Verfahren zum schuetzen eines turboverdichters vor pumpen mittels abblasens ueber ein abblaseventil sowie vorrichtung zur durchfuehrung des verfahrens
DE3811232A1 (de) * 1988-04-02 1989-10-26 Gutehoffnungshuette Man Regelverfahren zum vermeiden des pumpens eines turboverdichters mittels bedarfsweisen abblasens
FR2666854B1 (fr) * 1990-09-19 1992-12-18 Framatome Sa Dispositif de commande de moyens d'antipompage d'un compresseur.
US5306116A (en) * 1992-04-10 1994-04-26 Ingersoll-Rand Company Surge control and recovery for a centrifugal compressor
DE19528253C2 (de) * 1995-08-01 1997-10-16 Gutehoffnungshuette Man Verfahren und Vorrichtung zur Vermeidung von Reglerinstabilitäten bei Pumpgrenzregelungen beim Betrieb von Strömungsmaschinen mit Reglern hoher Prportionalverstärkung
DE19541192C2 (de) * 1995-11-04 1999-02-04 Ghh Borsig Turbomaschinen Gmbh Verfahren zum Schutz eines Turbokompressors vor Betrieb im instabilen Arbeitsbereich mittels einer Abblaseeinrichtung
DE19726547A1 (de) * 1997-06-23 1999-01-28 Babcock Bsh Gmbh Verfahren zur Bestimmung des Betriebspunktes eines Ventilators und Ventilator
DE10001365A1 (de) 2000-01-14 2001-07-19 Man Turbomasch Ag Ghh Borsig Verfahren und Einrichtung zum Regeln eines Turbokompressors zur Verhinderung des Pumpens
JP4069675B2 (ja) 2002-05-22 2008-04-02 株式会社日立プラントテクノロジー ターボ圧縮機およびその容量制御方法

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3797233A (en) * 1973-06-28 1974-03-19 United Aircraft Corp Integrated control for a turbopropulsion system
DE2623899B2 (de) * 1976-05-28 1979-11-29 Gutehoffnungshuette Sterkrade Ag, 4200 Oberhausen Verfahren zum Betreiben von Turboverdichtern in der Nähe der Pumpgrenze
US4139328A (en) * 1977-05-25 1979-02-13 Gutehoffnungshitte Sterkrade Ag Method of operating large turbo compressors
DE2735246C2 (de) * 1977-08-04 1985-07-18 Siemens AG, 1000 Berlin und 8000 München Regeleinrichtung für einen Turboverdichter
DE2739229C3 (de) * 1977-08-31 1980-07-10 Siemens Ag, 1000 Berlin Und 8000 Muenchen Regeleinrichtung für einen Turboverdichter
DE2852717C2 (de) * 1978-12-06 1982-02-11 M.A.N. Maschinenfabrik Augsburg-Nürnberg AG, 4200 Oberhausen Verfahren zur Enddruckbegrenzung für Turbo-Verdichter mittels Abblaseregelung
US4640665A (en) * 1982-09-15 1987-02-03 Compressor Controls Corp. Method for controlling a multicompressor station
US4560319A (en) * 1983-08-01 1985-12-24 MAN Maschinenfabrik Unternehmensbereich GHH Sterkrade Method and apparatus for controlling at least two parallel-connected turbocompressors
US4562531A (en) * 1983-10-07 1985-12-31 The Babcock & Wilcox Company Integrated control of output and surge for a dynamic compressor control system
US4627788A (en) * 1984-08-20 1986-12-09 The Babcock & Wilcox Company Adaptive gain compressor surge control system
US4586870A (en) * 1984-05-11 1986-05-06 Elliott Turbomachinery Co., Inc. Method and apparatus for regulating power consumption while controlling surge in a centrifugal compressor

Also Published As

Publication number Publication date
DE3540285A1 (de) 1987-05-14
US4789298A (en) 1988-12-06
EP0223208A3 (en) 1988-01-13
EP0223208A2 (fr) 1987-05-27
DE3674724D1 (de) 1990-11-08
JPS62113891A (ja) 1987-05-25

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