FR2503269A1 - Control circuit for hydraulic turbine gating - has double-acting servos controlling gates with leakage compensators - Google Patents

Control circuit for hydraulic turbine gating - has double-acting servos controlling gates with leakage compensators Download PDF

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Publication number
FR2503269A1
FR2503269A1 FR8106895A FR8106895A FR2503269A1 FR 2503269 A1 FR2503269 A1 FR 2503269A1 FR 8106895 A FR8106895 A FR 8106895A FR 8106895 A FR8106895 A FR 8106895A FR 2503269 A1 FR2503269 A1 FR 2503269A1
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France
Prior art keywords
oil
winnowing
stages
servomotors
control device
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Granted
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FR8106895A
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French (fr)
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FR2503269B1 (en
Inventor
Severin Casacci
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Neyrpic SA
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Neyrpic SA
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Priority to FR8106895A priority Critical patent/FR2503269A1/en
Publication of FR2503269A1 publication Critical patent/FR2503269A1/en
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Publication of FR2503269B1 publication Critical patent/FR2503269B1/fr
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03B—MACHINES OR ENGINES FOR LIQUIDS
    • F03B15/00—Controlling
    • F03B15/02—Controlling by varying liquid flow
    • F03B15/04—Controlling by varying liquid flow of turbines
    • F03B15/06—Regulating, i.e. acting automatically
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03B—MACHINES OR ENGINES FOR LIQUIDS
    • F03B3/00—Machines or engines of reaction type; Parts or details peculiar thereto
    • F03B3/16—Stators
    • F03B3/18—Stator blades; Guide conduits or vanes, e.g. adjustable
    • F03B3/183—Adjustable vanes, e.g. wicket gates
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/20—Hydro energy

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

The control is for the rotors of a turbine which have gates which can be regulated in two stages. It has a double acting hydraulic servo (10-12) for the gates with the oil fed from one stage to the next in series. There can be compensators (30,31) for oil leaks from the servos each connected to two successive stages and controlled by a signal (V1-V2,V2-V3) proportional to the position of the gates in the two stages.

Description

La présente invention se rapporte à la synchronisation des commandes de vannage des différents étages d'une turbomachine hydraulique multiétages, telle qu'une turbine-pompe multiétages par exemple. The present invention relates to the synchronization of the valve control commands of the different stages of a multi-stage hydraulic turbomachine, such as a multi-stage turbine-pump for example.

Le cercle de vannage d'une turbomachine(turbine hydraulique
FRANCIS par exemple) est manoeuvré classiquement par au moins un servomoteur à huile simple ou double-effet.The valve circle of a turbomachine (hydraulic turbine
FRANCIS for example) is conventionally operated by at least one single or double-acting oil servomotor.

Certaines turbomachines présentent au moins deux vannages c'est le cas des turbine-pompes multiétages à un réglage par étage. Certain turbomachinery have at least two valve winches, this is the case with multi-stage turbine pumps with one adjustment per stage.

Il convient alors de synchroniser au mieux les positions de chaque cercle de vannage ainsi que les vitesses de déplacement de ces mê- mes cercles de vannage.It is then advisable to synchronize as well as possible the positions of each winnowing circle as well as the speeds of movement of these same winnowing circles.

La solution classique pour réaliser cette synchronisation consiste à asservir l'ouverture de chaque cercle de vannage à une me- me consigne d'ouverture par l'intermédiaire de systèmes copiants électro-hydrauliques par exemple. Dans cette solution, la qualité de la synchronisation dépend de la précision statique et de la précision dynamique des systèmes copiants : ces précisions sont fonction de la valeur des efforts de frottement des cercles de vannage; ces efforts sont très variables d'un étage à l'autre. D'autre part en cas de défaillance d'un système copiant, entrainant l'ouverture ou la fermeture intempestive du cercle de vannage correspondant, la répartition des pressions le long de la veine hydraulique de la machine est fortement perturbée, et il existe un risque d'endommagement de la machine. The classic solution for achieving this synchronization consists in slaving the opening of each winnowing circle to the same opening setpoint by means of copying electro-hydraulic systems for example. In this solution, the quality of synchronization depends on the static precision and the dynamic precision of the copying systems: these precisions are a function of the value of the friction forces of the winnowing circles; these efforts are very variable from one floor to another. On the other hand in the event of a failure of a copying system, causing the untimely opening or closing of the corresponding winnowing circle, the distribution of pressures along the hydraulic flow of the machine is greatly disturbed, and there is a risk. damage to the machine.

La présente invention permet d'améliorer la qualité de la synchronisation et de supprimer le risque d'endommagement de la machine consécutif à une manoeuvre intempestive d'un vannage. Le dispositif de commande des vannages selon l'invention est du type com portant au moins un servomoteur douhle-effet à huile par vannage, et est caractérisé en ce que l'alimentation en huile desdits servomoteurs est effectuée en série d'un étage à l'autre.Par ailleurs, selon une autre caractéristique de l'invention, ledit dispositif de commande des vannages est avantageusement muni d'un ou plusieurs dispositifs de compensation des fuites d'huile dues aux imperfections éventuelles des étanchéités desdits servomoteurs, chacun desdits dispositifs de compensation étant placé entre deux étages successifs et étant commandé par un signal figuratif de l'écart de position entre les vannages de ces deux étages. The present invention improves the quality of synchronization and eliminates the risk of damage to the machine as a result of untimely maneuvering of a winnowing device. The valve control device according to the invention is of the com type carrying at least one douhle-effect oil servomotor by winnowing, and is characterized in that the oil supply to said servomotors is carried out in series from one stage to the next. In addition, according to another characteristic of the invention, said valve control device is advantageously provided with one or more devices for compensating for oil leaks due to possible imperfections in the seals of said servomotors, each of said devices compensation being placed between two successive stages and being controlled by a figurative signal of the position difference between the winnowing of these two stages.

L'invention sera mieux comprise à l'aide de la description suivante d'une commande de vannages pour turbomachine hydraulique à trois étages réglables, en référence aux dessins annexés dans les quels - la figure. 1 est un schéma d'ensemble du dispositif de commande de l'invention - la figure 2 est un schéma d'un des dispositifs de compensation de fuites d'huile équipant le dispositif de commande de la figure 1. The invention will be better understood using the following description of a valve control for a hydraulic turbomachine with three adjustable stages, with reference to the accompanying drawings in which - the figure. 1 is an overall diagram of the control device of the invention - FIG. 2 is a diagram of one of the oil leakage compensation devices fitted to the control device of FIG. 1.

Sur la figure 1, les références 1,2 et 3 désignent les cer- cles de vannage relatifs respectivement aux trois étages de la turbomachine et commandant chacun, de manière très classique, l'ouverture et la fermeture des aubes directrices associées à 1 'étage considéré.De manière très classique également, l'ouverture 0 ou la fermeture F des cercles de vannage(1,2,3) est effectuée à l'aide de tiges de commande(4,5,6) accouplées respectivement mécaniquement chacune au'aide des accouplements(7,8,9) à des servomoteurs double-effet(respectivement 10,11,12) à piston (respectivement 13,14,15) et à commande par huile, chacun desdits servomoteurs étant muni d'une entrée amont d'huile (respectivement 16,17,18) destinée à provoquer le déplacement du piston (respectivement 13,14,15) dans le sens 0 entraînant l'ouverture du vannage (respectivement 1,2,3), et d'une entrée d'huile. aval (respectivement 9,20,21) destinée à provoquer le dé- placement du piston dans le sens F entraînant la fermeture du vannage.Les trois servomoteurs(10,11,12) sont dimensionnés en fonction du cercle de vannage associé de manière à ouvrir, pour une même pression différentielle d'huile, chaque vannage(1,2 ou 3) d'une meme quan tité. Dans l'exemple considéré, les vannages(1,2 et 3) sont supposés identiques, et par suite les servomoteurs(10,11,12) sont également identiques. In FIG. 1, the references 1,2 and 3 designate the winnowing circles respectively relating to the three stages of the turbomachine and each controlling, very conventionally, the opening and closing of the guide vanes associated with the stage Considered also very conventionally, the opening 0 or closing F of the winnowing circles (1,2,3) is carried out using control rods (4,5,6) each mechanically coupled to the ' using couplings (7,8,9) to double-acting (respectively 10,11,12) piston actuators (respectively 13,14,15) and oil-controlled, each of said servomotors being provided with an upstream inlet oil (respectively 16,17,18) intended to cause the displacement of the piston (respectively 13,14,15) in direction 0 causing the opening of the valve (respectively 1,2,3), and of an inlet oil. downstream (respectively 9,20,21) intended to cause the displacement of the piston in the direction F leading to the closure of the valve body. The three servomotors (10,11,12) are dimensioned according to the associated valve body so as to open, for the same differential oil pressure, each valve (1,2 or 3) in the same quantity. In the example considered, the winnowing (1,2 and 3) is assumed to be identical, and consequently the servomotors (10,11,12) are also identical.

Conformément à l'invention, et comme on le voit clairement sur le dessin, les trois servomoteurs(10,11,12) sont branchés, en ce qui concerne leurs commandes par huile, en série. En conséquence, l'en- trée amont 16 du premier servomoteur 10 est reliée par une canalisation 22 a l'entrée aval 20 du second servomoteur 11,l'entrée amont 17 du second servomoteur 11 est reliée par une canalisation 23 à l'entrée aval 21 du troisième servomoteur 12, et ltensemble des trois servomoteurs est alimenté en série par l'intermédiaire d'une servovalve à huile 24 dont les deux sorties sont reliées respectivement à l'entrée aval 19 du premier servomoteur 1O par une canalisation 25 et à l'entrée amont 18 du troisième servomoteur 12 par une canalisation 26. According to the invention, and as can be clearly seen in the drawing, the three servomotors (10,11,12) are connected, as regards their oil controls, in series. Consequently, the upstream inlet 16 of the first servomotor 10 is connected by a pipe 22 to the downstream inlet 20 of the second servomotor 11, the upstream inlet 17 of the second servomotor 11 is connected by a pipe 23 to the inlet downstream 21 of the third servomotor 12, and all of the three servomotors are supplied in series via an oil servo valve 24, the two outputs of which are connected respectively to the downstream inlet 19 of the first servo motor 10 via a pipe 25 and to the upstream inlet 18 of the third servomotor 12 via a pipe 26.

Grâce à ce mode d'alimentation, les déplacements des pistons(13,14,15) s'effectuent nécessairement en synchronisme, la synchronisation étant obtenue par transfert d'un même volume d'huile d'un servomoteur à 1 'autre, ce qui supprime les risques qui seraient dus à une manoeuvre intempestive d'un vannage. Thanks to this supply mode, the displacements of the pistons (13, 14, 15) are necessarily carried out in synchronism, synchronization being obtained by transfer of the same volume of oil from one servomotor to another, this which eliminates the risks which would be due to an untimely operation of a winnowing.

Par ailleurs, conformément à une autre caractéristique avantageuse de l'invention, les petites fuites d'huile dues à l'imperfection éventuelle des étanchéités des servomoteurstlO,11,12) sont compensées en permanence et rapidement à l'aide des petites servovalves électro-hydrauliques pilotees chacune par un signal électrique figuratif de l'écart de position entre deux vannages successifs. Furthermore, in accordance with another advantageous characteristic of the invention, the small oil leaks due to the possible imperfection of the seals of the servomotors (11, 12) are compensated continuously and quickly using the small electro-servo valves. each controlled by a figurative electric signal of the position difference between two successive winnowing operations.

Comme on le voit sur la figure 1, un premier bloc d'asservissement 30 a ses entrées Ul et V2 reliées aux tiges 4 et 5 de commande des cercles de vannage 1 et 2, et sa sortie 32 constituée par une canalisation connectée a la canalisation 22. De même, un second bloc d'asservissement 31, identique au bloc 30, a ses entrées V2 et V3 reliées aux tiges 5 et 6 de commande des cercles de vannage 2 et 3 et sa sortie 33 constituée par une canalisation connectée à la canalisation 23. As can be seen in FIG. 1, a first control block 30 has its inputs Ul and V2 connected to the rods 4 and 5 for controlling the winnowing circles 1 and 2, and its output 32 constituted by a pipe connected to the pipe 22. Likewise, a second servo block 31, identical to block 30, has its inputs V2 and V3 connected to the rods 5 and 6 for controlling the winnowing circles 2 and 3 and its output 33 constituted by a pipe connected to the pipeline 23.

En se reportant maintenant à la figure 2, qui schématise à titre d'exemple le bloc 30, les points V1 et V2 sont accouplés à des capteurs de position 34 et 35 transformant leurs positions en signaux électriques qui sont comparés à l'aide d'un comparateur électronique, ou sommateur différentiel, 36. La différence E entre les positions(V1,V2) des tiges (4,5) liées aux servomoteurs(10,11) est traitée par un régulateur é lectronique 37 qui pilote une servovalve électrohydraulique 38, ellemême connectée à la canalisation 32 ainsi qu'à un réservoir d'huile par son entrée 40. Referring now to FIG. 2, which schematically shows block 30 by way of example, the points V1 and V2 are coupled to position sensors 34 and 35 transforming their positions into electrical signals which are compared using an electronic comparator, or differential adder, 36. The difference E between the positions (V1, V2) of the rods (4,5) linked to the servomotors (10,11) is processed by an electronic regulator 37 which controls an electrohydraulic servovalve 38 , itself connected to the pipe 32 as well as to an oil tank via its inlet 40.

On place avantageusement un diaphragme de limitation de débit (41,42, figure 1) sur chacune des canalisations 32 et 33, pour limiter les débits entrant ou sortant des servovalves telles que 38. Advantageously, a flow limiting diaphragm (41, 42, FIG. 1) is placed on each of the pipes 32 and 33, in order to limit the flows entering or leaving the servovalves such as 38.

Le fonctionement du bloc 30 est le suivant
Lorsque le vannage 2 est trop ouvert par rapport au vannage 1, l'écart
E, positif, pilote, par l'intermédiaire du régulateur 37, la servovalve 38 de manière à ce qu'elle injecte alors dans le canal 22 la quantité d'huile nécessaire aux servomoteurg pour obtenir l'identité des ouvertures de vannage et par suite l'annulation dudit écart E.The operation of block 30 is as follows
When valve 2 is too open compared to valve 1, the gap
E, positive, pilot, via the regulator 37, the servovalve 38 so that it then injects into the channel 22 the quantity of oil necessary for the servomotors to obtain the identity of the valve openings and consequently the cancellation of said deviation E.

Lorsqu'au contraire le vannage 2 est trop fermé par rapport au vannage 1, l'écart E, alors négatif, entraîne la soustraction de la quantité d'huile nécessaire a la synchronisation des positions des deux vannages.  When, on the contrary, the valve 2 is too closed with respect to the valve 1, the difference E, then negative, causes the subtraction of the quantity of oil necessary for the synchronization of the positions of the two valves.

Claims (3)

REVENDICATIONS 1. Dispositif de commande des vannages(1,2,3) d'une turbomachine hydraulique multiétages, ladite machine étant munie de vannages réglables sur au moins deux de ses étages, ledit dispositif de commande comportant au moins un servomoteur double-effet à huile(10,11,12) par vannage, caractérisé en ce que l'alimentation en huile desdits servomoteurs est effectuée en série d'un étage à l'autre.1. A control device for winnowing (1,2,3) of a multi-stage hydraulic turbomachine, said machine being provided with adjustable winnowing over at least two of its stages, said control device comprising at least one double-acting oil servomotor (10,11,12) by winnowing, characterized in that the supply of oil to said servomotors is carried out in series from one stage to another. 2. Dispositif de commande selon la revendication 1, caractérisé en ce qu'il est muni d'un ou plusieurs dispositifs(30,31) de compensation des fuites d'huile desdits servomoteurs, chacun desdits dispositifs de compensation étant branché entre deux étages successifs et étant commandé par un signal (vl-v2 ,v2-v3) figuratif de l'écart de position entre les vannages de ces deux étages.2. Control device according to claim 1, characterized in that it is provided with one or more devices (30,31) for compensating for oil leaks from said servomotors, each of said compensation devices being connected between two successive stages and being controlled by a signal (vl-v2, v2-v3) figurative of the position difference between the winnowing of these two stages. 3. Dispositif de commande selon la revendication 2, caractérisé en ce que chacun desdits dispositifs(30,31) de compensation des fuites d'huile comporte successivement (figure 2): - deux capteurs de position(34,35) fournissant chacun un signal figuratif de la position(V1,V2) de chacun des deux vannages(1,2) - un comparateur(36)fournissant à sa sortie un signal différentiel (E) figuratif de la différence des signaux issus desdits capteurs de position T un régulateur 37 pilotant une servovalve à huile(38) de manière à lui faire injecter ou soustraire, dans le circuit d'huile des servomoteurs(10,11) des deux étages considérés, la quantité d'huile entrai- nant l'annulation du signal différentiel(E). 3. Control device according to claim 2, characterized in that each of said devices (30,31) for compensating for oil leaks successively comprises (FIG. 2): - two position sensors (34,35) each supplying a signal figurative of the position (V1, V2) of each of the two winnowing (1,2) - a comparator (36) supplying at its output a differential signal (E) figurative of the difference of the signals coming from said position sensors T a regulator 37 controlling an oil servovalve (38) so as to cause it to inject or subtract, in the oil circuit of the servomotors (10,11) of the two stages considered, the quantity of oil causing the cancellation of the differential signal ( E).
FR8106895A 1981-03-31 1981-03-31 Control circuit for hydraulic turbine gating - has double-acting servos controlling gates with leakage compensators Granted FR2503269A1 (en)

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FR8106895A FR2503269A1 (en) 1981-03-31 1981-03-31 Control circuit for hydraulic turbine gating - has double-acting servos controlling gates with leakage compensators

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FR8106895A FR2503269A1 (en) 1981-03-31 1981-03-31 Control circuit for hydraulic turbine gating - has double-acting servos controlling gates with leakage compensators

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FR2503269A1 true FR2503269A1 (en) 1982-10-08
FR2503269B1 FR2503269B1 (en) 1983-05-06

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE712890C (en) * 1939-09-30 1941-10-27 Arno Fischer Turbine or pump unit
DE2424493A1 (en) * 1973-05-23 1974-12-05 Fuji Electric Co Ltd METHOD AND DEVICE FOR CONTROLLING THE SPEED OF A WATER WHEEL
US4137004A (en) * 1976-05-07 1979-01-30 Hitachi, Ltd. Operation-control method for hydraulic machine

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE712890C (en) * 1939-09-30 1941-10-27 Arno Fischer Turbine or pump unit
DE2424493A1 (en) * 1973-05-23 1974-12-05 Fuji Electric Co Ltd METHOD AND DEVICE FOR CONTROLLING THE SPEED OF A WATER WHEEL
US4137004A (en) * 1976-05-07 1979-01-30 Hitachi, Ltd. Operation-control method for hydraulic machine

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