AU613986B2

AU613986B2 - Turbine with control device and use of said turbine

Info

Publication number: AU613986B2
Application number: AU26036/88A
Authority: AU
Inventors: Wolfgang Wuhrer
Original assignee: Sulzer AG
Current assignee: Sulzer AG
Priority date: 1987-11-30
Filing date: 1988-11-11
Publication date: 1991-08-15
Anticipated expiration: 2008-11-11
Also published as: AU2603688A

Description

OPI DATE 05/07/89 APPLN, ID 26036 /88 PCI A -E ~~CNME PCT/CH88/00209 INTERNATIONALE ANMELD HI-lk UL H M VRIRAU UBERDIE INTERNATIONALE ZUSAMME% RBtYT D GW~T1I AETEESPT (51) Internationale Patent klIassif ikation 4: (11) Internationale V~eroffentlichungsnummer: WVO 89/ 05402 F03B 15/20, 11/00 Al k43) Internationales N'eroffentlichungsdatum: IS J u ni 1939 (15.06.89) (21) Internationales Aktenzeichen: PCT/CH88/00209 V'eroffentlicht Mit internationalem Recherchenbericht.

(22) Internationales Anmeldedaturn: 11. November 1988 (11.11.88) (31) Prioritatsaktenzeichen: 4664/87-3 (32) Priorititsdatum: 30. November 1987 (30.11.87) (33) Prioritatshind: CH (71) Anmelder (fi~r alle Bestirnmungssaaen ausser US,: GE- BRUDER SULZER, AKTI ENG ESELLSC HAFT [CH/CH]; Z~rcherstr. 9, CH-8401 Winterthur (CH).

(72) Erfinder; und Erfinder/Anmelder (nur fli U.5S WORRER, WVolfgang [AT/DiE]; Staufenstr. 54, D-7980 Ravensburg (DE).

(81) Bestimmungsstaateri: AU. JP. US.

(54) Title. TURBINE WITH CONTROL DEVICE AND USE OF SAID TURBINE (54) Bezeichnung: TURBINE MIT STEUERUNG UND VERWENDUNG DER TURBINE (57) Abstract A turbine ha. .i control and re- 33 gulating device with a pump (31) w~hose 113 pressure v'aries as the square of the vo- C -1 37 lume delivered by the pump or as the2-31 square of the rotational speed (n2) of th~e 3 turbine The hydraulic sequential pis- 2 4 5 1/ ton arrangement comprising a prelimi- 72 L nary control piston (41) and a control piston for regulating the rotation speed of 4 the turbine is supplied by a single pump A compact, space-saving construc- I10- tion is thereby achieved. The turbine is suitable for use as a motor or drive in ap-521L plications other than the generation of5 electricity, for example for cable winches.503 (57) Zusammenfassung __33 -3_ Die Turbine verfi~gt ilber eine Steuer- und Regelanlage. mit eintr Pumpe (3 deren Druck sich proportional zuIm Quadrat des Pumpenf6rderstroms oder zum Quadrat der Drehzahl (n 2 der Turbine andert. Die Hydraulische Folgekolbenanordung mit dem Vorsteuerkolben (41) und dem Steuerkolben fMr die Drehzahlregelung der Turbine, wird von dieser einzigen Pumpe (31) gespeist. was eine besonders kompakte und raumsparende Bauweise erlaubt. Die Turbine ist als Motor bzwv. Antrieb bei Anwendlungen ausserhalb der Stromerzeugung, wie beispielsweise for Seilwinden geeignet.

-2- The invention relates to a turbine with a control and regulating system for adjuisting the nozzle, as well as to the use of such a turbine.

Control and regulating systems for turbines serve to keep the speed constant independent of the load. For turbines, in particular also for water-operated Pelton turbines, for example, so-called needle valves are frequently used, wherein a conical needle moves axially in a tube-like counterpart, so that a greater or lesser quantity of water is let through by which the power output of the turbine can be adapted to the respective requirements.

Regulated turbines of the described type are used mainly as a drive for generators, i.e. for generating electricity. With this application very precise regulation is required, which in the event of changes in the loao i.e. the switching on and off of electrical appliances by consumers, adapts the power output of the turbine practically without changing its speed. In this connection we speak of the statics of the turbine regulating system. The smaller the statics of a turbine regulating system, the more the speed of a turbine will be kept constant during changes in the load. Regulating systems with small statics are complicated and, therefore, expensive to produce.

If a turbine is used to drive, for example, a rope winch, it is also desirable to regulate the speed or power output of the turbine u 3 within certain limits. However, here one can dispense with the P

|L

i B -3small statics which are absolutely essential for generating electricity.

It is an object of this invention to provide a turbine, the regulating and control of which is adequate foL machines, which machines exclude large electrical power stations which have to be synchronized in phase with an operating electrical network.

According to the invention such a turbine is characterized in that the hydraulic control and regulating system comprises a follow-up piston arrangement with a pilot piston and a control piston, as well as a hydraulic pump which produces a pressure which is dependent on the speed of the turbine, in that the delivery of the pump is passed at least partly through a first branch with the pilot piston and through a parallel, second branch with the control piston of the control and regulating system for the nozzle, o and in that each of the two branches has at least one S orifice plate. The sub-claims refer to advantageous S embodiments of the invention.

The invention permits a particularly simple and, therefore, also economical construction of the turbine drive, and has regulating properties which suffice for .00:0 applications other than the generating of electricity.

Furthermore, the invention permits, for example, the compact construction of a turbine with internal type control valve, O wherein, for example, the needle valve, with the controlled and regulated follow-up piston drive, i.e. the control servo, are arranged in the flow of motive water of the turbine. A control servo of the follow-up piston type permits the construction of B IAS/RCTS:JJC (6/36) pi/

Z

Nor- 4 a practically hysteresis-free regulating and control system, since possible friction influences which could delay the axial displacements can be largely eliminated with this.

*r 0 0 0* 0@ *00* 00 *0 0 00

'A.

0 0 With a small turbine it may be advantageous if the housings of the turbine and pump or gear mechanism are flanged directly together in the compact construction. The wall between the turbine chamber and the pump or gear chamber is in this case touched by water on the turbine side and by air on the other side. In principle, the risk exists that water of condensation could form in the gear or pump chamber. If the wall is constructed as a cooling wall with channels for the oil supplied by the pump, the formation of water of condensation is prevented, because in this case the gear or pump chamber will not have a low temperature zone where water of condensation could form. At the same time the flow of oil supplied by the gear unit or pump is cooled in by giving off its heat in the turbine chamber and, in particular, to the turbine water.

The use of such a turbine as a drive for a winch is particularly advantageous in the mining industry, especially in underground mines. Such a turbine drive is per s6 explosion-proof and does not produce noxious waste gases. The drive medium water is also required elsewhere in the mines, for example for cooling purposes or for washing the mined material. The height of fall of the water resulting from the depth of the shaft, gallery or pit is available as an inexpensive, practically free source of energy for driving the turbine. The available water pressure may amount to between n 5 a few bar to as much as 200 bar or more. The compactness and simplicity of the turbine with the control system also permits its use as a drive or motor for machines used in changing locations. In the mining industry the mechanical equipment, e.g. rope winches for stripping machines, so-called ore scrapers, must from time to time be moved up in the advancing gallery. Under difficult underground conditions even the smallest saving in mass and/or reduction in size of the equipment may already offer significant advantages.

Thus, for example, a turbine drive with the power output from about

*CCC

20 kW to 60 kW may only weigh about one third of the mass of about S 300 kg of an explosion-proof electric motor with the same power output. This provides considerable advantages in the handling of the equipment operated with such turbines, e.g. winches.

In the following the invention and its mode of operation will be explained in greater detail with reference to the examples illustrated in the diagrammatic figures.

Shown are:

CC

Fig. 1 a Pelton turbine with needle valve and hydraulic regulating and control system, Fig. 2 diagrarrm tically in section, a Pelton turbine with flangedon gear or pump housing, with the dividing wall constructed as a cooling wall.

The Pelton turbine 1 with the blades 11 is driven by the water I Y 1 0v l y V^V 'i 1

PP

6 jet 1C; uhich comes out of the nozzle 20 of the needle valve 2.

The control and regulating of the power output or speed of the turbine 1 is ensured by the hydraulic regulating and control system In the example, the needle valve 2 is mounted on the inside.

j pump 31, e.g. a geared pump, is driven by the turbine via a gear unit (not illustrated), and supplies oil from the tank 31 through the system 3, which at point 3334 splits into two -branches 33 and 34. The branch 33 leads to the control piston 5 and the branch 34 (the actual measuring circuit) to the pilot piston 46.

SThe hydraulic oil flows through the return lines 33' and 34', re- S* spectively, which again combine at point 3334', back into the tank 23. In the branch 34, 34' the orifice plates 35 and 36 are provided for the oil flow. In the branch 33, 33' a first orifice plate 37 *s is provided. A second orifice is formed in this branch by the piston rod 41 with the axial bore 40 and the opposite end face 51 of the control piston 5, i.e. by the gap which lies inbetween. In the illustrated example the end of the piston rod 55 is constructed as the nozzle needle 52 of the needle valve 2.

S

S The pilot piston and control piston are guided and arranged in the houding 5. The housing 5 is provided on the outside with, for example, 3 webs 53 (only two are shown) by which the housing 4 is positioned and held in this position in the needle valve housing in the flow of motive water. The hydraulic lines may, for example, pass through these webs. One coil spring each, 54 and 45, press the control piston and the pilot piston 4, respectively, towards the rear into their starting position.

le A I'i" I I WMMEOMMM;r 7 The control and regulating system for regulating the turbine speed operates as follows: At a specific speed the pump 31 produces a pressure in the hydraulic circuit which is proportional to the second power of the speed n In the branches of the hydraulic system 3 there occurs on the whole a drop in pressure of the same magnitude. The orifice plate or throttle 35 in the branch 341, 34' ensures that, seen in the direction of flow, a pressure builds up in front thereof.

.4 In the same way, pressure also builds up in front of the orifice plate 36. The pair of orifice plates 35, 36 in the branch 34, 34' act as a pressure divider, and thus determine the magnitude of o the pressure which in the piston chamber 46 acts on the end face Sof the piston 41.

In the branch 33, 33' the orifice plate or throttle 37 and the annular orifice which is formed by the end face 51 and the piston rod 41 with the bore 40 open on the side of the end face, act as

S*

a pressure divider.

o* As the speed n of the turbine 1 increases, the pressure (measuring pressure) in the piston chamber 46 increases and presses and moves the pilot piston 4 by way of the pilot piston rod 41 against the pressure or the force of the spring 45 in the direction of the control piston 5, so that the gap of the annular orifice becomes smaller. Now the pressure in the piston chamber 50 increases and the control piston is moved in the direction of the nozzle 20 against 0

J'

the pressure of the spring 54 and the axial forces exerted by the motive water on thle piston rod 55. As a result thereof the open cross-section of the nozzle 20 is reduced, the driving water jet becomes smaller and the speed n of the turbine 1 also drops.

This again causes the pressure in the piston chamber 46 of the pilot piston to drop, and thle pilot piston with the pilot piston rod 4l moves away from the control piston into a new equilibrium position. As a result thereof the annular orifice between the piston chamber 50 and the bore 40 becomes larger, which causes a drop .in pressure in the piston chamber 50, and the piston 5 follows the pilot piston 41. Due to this, the cross-sec tiost of the nozzle open for the motive water becomes larger, which now causes an increase in the speed n of the turbine 1. Every load or speed change of the turbine 1 immediately results in such a regulating operation, wherein for every speed n of the turbine 1 at a specific load and a spring with a specific spring constant, the needle 52 finally *assumes a very specific equilibrium posi tion, or the needle is regulated to this position.

By dimensioning measures which are known to the expert, it is easily possible to dimension the control and regulating system in such a way that this does not oscillate. The spring constant of the springs 45 and 54, for example, determine to a large extent the statics of the regulation. The regulating properties may, for example, also be improved when the flow, i.e. the throughflow in the branch 34, 34' of the pilot piston 4, is chosen greater than the flow in the branch 33, ~'of the control piston S.

i 9 To practically eliminate axial forces of the hydraulic liquid in the branch 33, 33' on the piston rod 41 of the pilot piston, the bore 40 in the piston rod 41 may taper down towards the inside, e.g. conically, or may be provided with a step, and on the outside in the piston chamber 50 the piston rod 41 may have a cylindrical shape.

In the arrangement described in the foregoing the turbine 1, at a givwn pressure of the motive water, is designed for a specific 4 speed n. The adjusting and changing of the nominal speed at the 4 same pressure of the motive water can be effected very easily by means of a third branch 7, a bypass with valve 71 in the hydraulic pump circuit. Depending on the regulating accuracy, it is also possibly to supply the lubrication of the turbine 1 and of the non-i'lustrated gear unit with the pump 31 of the control and regulating system, by way of a lubricating branch. Such measures aid a compact construction of the turbine 1 with control and regulating system. The use of two orifice plates in each branch of the hydraulic control and regulating circuit ensures good regulating properties.

However, there are also cases where a sufficiently good regulation I can already be obtained with just one orifice plate in each branch.

With Pel.ton turbines 1 which reach speeds of several thousands of revolutions per minute it is necessary to reduce the speed on the driven side by means of a gear unit. If the gear unit must be cooled, provision may be made to pass the oil in the hydraulic circuit through a cooler which is not illustrated here. The oil

I

10 in the control and regulating circuit may, if required, also be passed through and cooled by this cooler. Although the example relates to a Pelton turbine with needle valve for the nozzle, the patent; is not limited to this application, but also covers other turbine types and their control systems.

With the turbine 6 with the Pelton wheel 61 in the turbine-housing chamber 60 in the turbine housing 62, illustrated in the diagrammatic section of Fig. 2, the gear and/or pump housing is fastened directly 0* to the wall 67 of the turbine 6. The plate 8 with the channels 80 and the wall 67 of the turbine housing form a cooler for the liquid delivered by a pump, which is not illustrated here, and/or 0O 'bo of a gear unit in the gear housing or pump housing chamber

C

As a result thereof the gear housing or pump housing chamber does not have a zone with a considerably lower temperature, which is greatly cooled by the turbine water and in which water of condensation could form. The surface of the heat exchanger 67, 8, facing the pump housing or gear housing chamber 70 is adequately 04 heated by the to be cooled flow of warm liquid.

c This heat exchanger could, of course, also be designed as part of one of the housings 6 or 7. Whatever construction is chosen, all that is important is that during operation no low temperature zone is formed in the gear housing or pump housing chamber where water of condensation can form.

f)]

Claims

1. A hydraulic turbine with control and regulating system for adjusting the speed of the turbine, characterized in that the control and regulating system comprises a follow-up piston arrangement with a pilot piston and a control piston, as well as a hydraulic pump which produces a pressure which is dependent on the speed of the turbine, in that the delivery of the pump passes at least partly through a first branch with the pilot piston and through a parallel, second branch with the control piston of the control and regulating system for a nozzle, and in that each of the two branches is provided with at least one orifice plate.

2. A turbine according to Claim 1, characterized in that the piston rod of the pilot piston directed towards the control piston is designed as an annular orifice in the hydraulic branch of the control piston.

3. A turbine according to Claim 1 or 2, characterized in that the piston rod of the control piston is designed as the nozzle needle of a needle valve of the turbine control system.

4. A turbine according to Claim 2 or 3, characterized in that the piston rod of the pilot piston has an axial bore which tapers down towards the inside of the piston, which bore forms part of af'annular orifice. A 'turbine according to one of Claims 1 to 4, characterized in that the pump produces a pressure which is proportional to the second power of the speed, or its delivery is proportional to the second powez of the speed of the turbine.

IAS/RCTS:JJC (6/36) 'I0 i i. r_ I i.. 12

6. A turbine according to one of Claims 1 to characterized in that the pump is pump which has a flow linearly proportional to pump speed and independent of counterpressure.

7. A turbine according to one of Claims 1 to characterized in that the pilot piston of the control an regulating system, on which -4he- measuring pressure acts, is loaded by a spring with an elective spring constant.

8. A turbine according to one of Claims 1 to 6, Ga.. characterized in that each of the parallel hydraulic S branches is provided with at least two orifice plates.

9. A turbine according to one of claims 1 to 8, characterized in that the hydraulic pump is a gear pump. a .e A turbine according to one of Claims 1 to 9, characterized in that the turbine has a lubricating branch for a gear unit provided after the turbine, which lubricating branch is fed by the hydraulic pump.

S

11. A turbine according to one of Claims 1 to q, S. Scharacterized in that at least part of the housing of the turbine is designed at least as part of a cooler for the S flow supplied by the pump and/or a gear unit.

12. A turbine according to Claim 11, characterized in that the cooler is formed by part of the housing of the turbine and a sealing plate with channels thereon provided for a circulating flow.

13. A turbine according to Claim 11 or 12, characterized in that, in the area of the cooler, a pump and/or gear housing is fastened to the housin of the turbine. IAS/RCTS:JJC (6/36) -M m -13-

14. A turbine according to claim 13, characterised in that there is a wall between turbine housing and gear housing which is in contact with splash water at the turbine side and which is constructed as a cooler for a flow of gear lubricant and/or for a flow from a hydraulic pump.

Use of a turbine as claimed in any one of the preceding claims as a drive for a rope winch.

16. Use of a turbine as claimed in claim 15 for the mining industry, especially in underground mines.

17. A turbine as claimed in claim 1, substantially as hereinbefore described with reference to the accompanying drawings. DATED this 21st day of May, .991. SULZER BROTHERS LIMITED 0 0 0000 0 0000 00 f 0 0 0000 0 0 00 0 WATERMARK PATENT ATTORNEYS 2ND FLOOR "THE ATRIUM", 290 BURWOOD ROAD, HAWTHORN, VIC. 3122. AUSTRALIA Melb Disk 10/1.51 MG