CN106884686B

CN106884686B - Power station transmission line

Info

Publication number: CN106884686B
Application number: CN201610940644.8A
Authority: CN
Inventors: M.哈尔德
Original assignee: Voith Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2015-10-22
Filing date: 2016-10-24
Publication date: 2020-07-07
Anticipated expiration: 2036-10-24
Also published as: CN206487512U; CN106884686A; DE102015220618A1

Abstract

The invention relates to a power plant transmission line with a steam turbine and/or a gas turbine operating at a constant rotational speed for driving a generator; a variable-speed pump for conveying and/or compressing a working medium or exhaust gas produced in a process supply or gas turbine of a drive and/or process supply steam turbine and/or gas turbine, wherein the variable-speed pump, in particular a boiler feed water pump, is driven by means of the steam turbine and/or gas turbine, wherein a variable-speed transmission is arranged in the drive connection, comprising at least one inlet, an outlet and a power branch with at least one first power branch and a hydraulic second power branch, wherein the drive power is branched off from the first power branch by means of a hydraulic power branch via a hydrodynamic coupling or a hydrodynamic converter, and the first power branch is rotationally variably re-input on the drive output side by means of a superimposed transmission; wherein the steam turbine and/or the gas turbine are connected to the power transmission device via a connecting device with axial length compensation.

Description

Power station transmission line

Technical Field

The invention relates to a power station transmission line, comprising: a steam turbine and/or a gas turbine operating at a constant rotational speed for driving an electric generator; a variable-speed pump for conveying and/or compressing a working medium for driving and/or process-supplying the steam turbine and/or the gas turbine or for conveying and/or compressing exhaust gases formed in the process supply or the gas turbine, wherein the variable-speed pump, in particular a boiler feed water pump, is driven by means of the steam turbine and/or the gas turbine; and a power transmission device arranged in the drive connection and designed as a speed-adjustable transmission, comprising at least one inlet, an outlet and a power branch with at least one first power branch and a hydraulic second power branch, wherein the drive power is branched off from the first power branch by means of the hydraulic power branch via a hydraulic coupling or a hydraulic converter and is rotationally variably re-input to the first power branch on the drive output side by means of the superimposed transmission.

Background

A power plant transmission line of this type is described in document WO 2011/124322 a 2. The power plant transmission line has a steam turbine and/or a gas turbine for driving an electrical generator, which is driven by one or more steam turbines and/or gas turbines. The steam turbine and/or the gas turbine are operated at a constant rotational speed in order to be able to generate electrical energy with a predetermined number of hertz or frequency by means of the generator. The steam turbine and/or the gas turbine drive a variable-speed pump, which is thus mechanically coupled to the steam turbine or the gas turbine. The variable-speed pump can be designed, for example, for conveying and/or compressing a working medium which drives the steam turbine and/or the gas turbine. In one embodiment, the pump is a boiler feed pump, which feeds the working medium of the steam turbine to the steam generator. In the drive connection (triebverbinding) between a variable-speed pump and a steam turbine and/or a gas turbine which drives the pump, a speed-adjustable transmission is arranged, which comprises a power branch with a mechanical, in particular only mechanical, main branch and a hydraulic auxiliary branch. In this case, the drive power is branched off from the main branch by means of a hydrodynamic auxiliary branch via a hydrodynamic coupling and/or a hydrodynamic converter, and the main branch is reentered on the transmission output side by means of a subsequent superposition transmission. In order to achieve a short overall length of the power plant drive train, the turbine is directly upstream of the speed-adjustable gearbox.

During operation, the turbine is uniformly at operating temperature. This produces heat induced expansion. The operating time of this type of turbine can be as long as several hours, depending on the model and the conditions of use. In this case, mechanical stresses due to the different degrees of thermal expansion of the individual components of the turbine and the connecting element in the power plant drive train, which would lead in particular to impaired operating performance and increased wear of the speed-adjustable transmission directly downstream of the turbine, should not develop. The reduction of the thermal expansion of the turbine and the connecting component and thus the stress applied in the power plant drive train can be achieved in the turbine by a modified material selection of the turbine and the connecting element.

Disclosure of Invention

The object of the present invention is therefore to improve a power plant drivetrain of the type mentioned above such that the drive connection between the turbine and the speed-adjustable transmission on the one hand meets the requirement for compensating for excessive thermal expansions of the components of the turbine and the connecting element while the axial structural length of the power plant drivetrain is low, and furthermore is of very simple and robust design and is distinguished by simpler assembly, lower axial length and lower costs.

The object is achieved by the power plant transmission line described above, according to the invention in that the steam turbine and/or the gas turbine are connected to the power transmission system by a connecting device with axial length compensation.

The power plant drive train has a steam turbine and/or a gas turbine operating at constant rotational speed for driving a generator and a pump with adjustable rotational speed. The speed-adjustable pump is used for conveying and/or compressing a working medium which drives and/or processes the steam turbine and/or the gas turbine, or for conveying and/or compressing exhaust gases formed in the process supply or the turbine. The pump with adjustable rotational speed is driven by means of a steam turbine and/or a gas turbine. A power transmission device designed as a speed-adjustable transmission is arranged in the drive connection of the turbine and the speed-adjustable pump. The power transmission device comprises at least one inlet, an outlet and a power branch with a first power branch and a hydraulic second power branch, wherein the drive power is branched off from the first power branch by means of the hydraulic power branch via a hydrodynamic coupling or hydrodynamic converter and is rotationally speed-adjustably fed back into the first power branch on the transmission output side by means of a superposition transmission. According to the invention, the power plant drive train is characterized in that the steam turbine and/or the gas turbine are connected to the power transmission device via a connecting device with axial length compensation.

By providing a separate connecting device with axial length compensation, stresses due to thermal expansion of the turbine, which would otherwise be introduced into the connection to the speed-adjustable transmission and the speed-adjustable transmission, can be compensated in a simple manner. The connection device can be constructed as a separate component of standard construction specifically adapted to the specific application without additional modification of the turbine and/or the power transmission apparatus.

In a preferred embodiment, the connecting device is designed such that the maximum possible axial length compensation of the connecting device is in the range from 10 to 50cm, preferably from 10 to 30 cm. This range of availability is mainly satisfactory for high power generation equipment.

The coupling device is designed as a tooth coupling, in particular as a circular tooth coupling, which is simple, not susceptible to interference and inexpensive. The coupling device can be designed as a single-tooth coupling or as a double-tooth coupling, in particular as a single-or double-arc tooth coupling, wherein a support element with an axial dimension, preferably in the form of a support cage, is provided, which has at least one toothed region that can be brought into engagement with a region of at least one coupling element with teeth that can be brought into engagement with the teeth. Preferably, a region with two teeth of this type is provided at the respective axial end region of the carrier element, wherein a first region with teeth is operatively connected, i.e. meshes, with a connecting element for connection to the turbine, and a second region with teeth is operatively connected, i.e. meshes, with a connecting element of a transmission with adjustable rotational speed, in particular with a connecting element of an inlet of a power transmission device. The toothing can be an external or internal toothing, depending on the design of the toothing on a connecting element coupled to or formed by the turbine or the speed-adjustable transmission. Preferably, the teeth designed as internal teeth are generally rectilinear, while the external teeth are designed almost spherically. This enables compensation of angular axial misalignment, wherein the special spherical shape allows for higher slip angles. The double toothed coupling offers the advantage that the connection of the turbine to the transmission with adjustable rotational speed is effected only by means of a single connection device in the case of very different connection geometries and dimensions of the turbine and the transmission with adjustable rotational speed. The permissible radial axial offset for a double-tooth coupling is proportional to the distance between the two pairs of teeth.

For a power plant having the desired low axial overall length, a transmission with adjustable rotational speed is preferably used, wherein the first and second power branch lines are arranged eccentrically, preferably parallel to one another. For this purpose, the power branch is coupled via a transfer gear to the input of the speed-adjustable transmission and via a superposition transmission to the output. In principle, different embodiments may differ. In a transmission with a rotational speed which is adjustable and has an eccentrically arranged power branch according to a first embodiment, a fluid coupling is provided in the first power branch, which fluid coupling comprises at least one pump impeller and a turbine impeller. The second power branch comprises a hydrodynamic speed/torque converter with at least one pump impeller, a turbine impeller and a guide wheel. The hydrodynamic speed/torque converter and the hydrodynamic coupling are arranged eccentrically to one another and are each connected to the inlet of the power transmission device via a transfer gear arranged in the housing in order to form a second power branch.

Preferably, the hydrodynamic components are arranged in power branches arranged parallel to one another. This parallel arrangement can be done in the mounting position in a horizontal or vertical plane and in planes offset from each other horizontally and vertically. The parallel arrangement may be accomplished in one axial plane or in multiple axial planes offset from each other. The arrangement of the hydrodynamic component with an offset in the axial direction is advantageous in that an additional functional unit is also integrated in the respective power branch. Additional components of this type may be, for example:

a) a second converter having a different conversion characteristic in the second power leg. The advantage is that the efficiency of the drop in the rotational speed range is increased.

b) An additional brake between the turbine wheel of the fluid coupling and the rotary drive mechanism in the first power branch.

However, it is also possible to integrate the aforementioned additional components axially without any offset in the arrangement of the hydrodynamic components provided in the two power branches.

The eccentric arrangement of the hydrodynamic component offers the advantage that, on the one hand, expensive swivel joints, in particular in a parallel arrangement, can be dispensed with, and, on the other hand, a transmission with adjustable rotational speed and thus a power plant transmission line with an axially compact construction can be provided. Furthermore, the possible integrated transmission ratios determined by the parallel arrangement allow the drive rotational speeds of the individual hydrodynamic components to be varied and converted in a corresponding manner, so that, on the one hand, compact, small hydrodynamic units can be used, and, in addition, a transmission with a variable rotational speed can be retrofitted in existing installations in a simple manner and without additional measures, in particular without a transmission ratio having to be provided. Depending on the design of the transfer case, the speed-adjustable transmission can be adapted to the requirements of the application in a desired manner and method.

Typically, power transmission is achieved in different operating regions through a fluid coupling and a fluid converter. In particular, in order to achieve a soft start and to control/regulate the transmission in the first power branch in a partial region of the total operating range, the hydrodynamic coupling is designed as an adjustable coupling (Regelkupplung) for this purpose. This can be achieved in different ways and methods. In the simplest case, the adjustable coupling has an adjusting device which comprises a dip tube for influencing the amount of operating medium. The dip tube is adjustable. The adjustability may be achieved with a directional component in the radial and/or axial direction. Other possibilities are to actively control the input of the operating medium and/or the output from the working cycle.

In a development of the first embodiment, means for engaging or bridging the fluid coupling are provided for mechanical communication between the inlet and the outlet. In the simplest case, the device for connecting or bridging the fluid coupling is designed as a mechanical bridging coupling. The means for switching on and the fluid coupling can be connected at least in parallel. The ability to connect at least the fluid coupling and the switchable coupling in parallel means that each coupling itself is actuated independently and independently of the other couplings. In this case, the force transmission is effected in at least one operating state exclusively via a respective coupling. It is also conceivable that both couplings can be operated in other operating states, wherein the switchable coupling in this state then bridges the still filled fluid coupling, so that no torque is transmitted via the fluid coupling itself, while nevertheless a mechanical connection between the inlet and the outlet is still achieved.

In a particularly preferred embodiment, for the first embodiment in which the power branch is arranged eccentrically, the first and second power branch have no further additional rotational speed and/or torque conversion means, and only one fluid coupling and one converter are provided. In this case, the power transmission device is particularly short.

In the case of a transmission with a speed-adjustable transmission according to the second embodiment, the first power branch line is designed as a mechanical feed-through completely free of hydrodynamic components. A mechanical feedthrough is understood to mean a direct coupling between the output of the transfer case and the input of the superposition transmission without rotational speed and/or torque conversion being possible. In the simplest case, this is a connecting shaft arrangement consisting of one or more shafts connected in a rotationally fixed manner. The second power branch comprises at least one hydraulic speed/torque converter and, in a special embodiment, two hydraulic torque and/or torque conversion devices.

The eccentric arrangement of the hydrodynamic converter and the purely mechanical feedthrough offers the advantage that, on the one hand, expensive swivel joints, in particular in the case of a parallel arrangement, can be dispensed with and, on the other hand, a power transmission device having an axially compact design can be provided. By means of the possible integratable transmission ratios resulting from the parallel arrangement, the drive rotational speeds in the individual power branches can be varied and varied in a corresponding manner and method and can thus be better adapted to the specific operating conditions.

The transfer case for the respective embodiment comprises at least one inlet opening which forms the inlet opening of the power transmission device or is at least indirectly connected in a rotationally fixed manner to the inlet opening of the power transmission device. The transfer case comprises at least two outlets which are arranged eccentrically to one another, wherein the first outlet is connected at least indirectly to the first power branch, in particular to the mechanical feed-through for the second embodiment or to the pump impeller of the hydrodynamic coupling for the first embodiment, and the second outlet is connected at least indirectly to the pump impeller of the hydrodynamic speed/torque converter. This achieves a torque transmission to the individual hydrodynamic components or to the individual power branches.

The specific construction of the transfer case itself has many possibilities in view of the use and construction of the hydrodynamic components and the superimposed transmission. The inlet of the transfer case can be arranged coaxially or eccentrically with respect to the inlet of the respective power branch, wherein the inlet is formed by a pump impeller of one of the hydrodynamic components or the shaft of the mechanical feedthrough. The coaxial arrangement offers the advantage that one of the power branches is directly loaded by the torque applied to the input of the transmission with adjustable rotational speed, while the eccentric arrangement allows a transmission ratio which leads to a deceleration or acceleration to be integrated into the respective power branch, so that it can be better adapted to the particular application in the case of an ideal design of the components.

According to a first embodiment, the transfer gear can be designed to have a reduction-inducing transmission ratio for the first and/or second power branch, while according to a second embodiment, the transfer gear is designed to have an acceleration-inducing transmission ratio for the first and/or second power branch. The basic configuration can thus be adapted to different drive train requirements in a simple manner without further modifications by merely providing hydraulic components and transfer gears.

In an advantageous embodiment, the transfer case comprises at least one spur gear set, wherein the outlet of the transfer case is coupled to or formed by a spur gear in order to drive the outlet in the same direction of rotation.

In particular in the case of hydrodynamic converters which are designed as reversing converters and in particular superposition transmissions with different directions of rotation at the inlet, the transfer case comprises a spur gear set with two or an even number of spur gears, wherein the first outlet of the transfer case is formed by a first spur gear and the second outlet of the transfer case is formed by a second spur gear or another spur gear which is driven in the opposite direction to the direction of rotation of the first spur gear. In contrast, in a power transmission device having a hydrodynamic converter as a converter in the same direction, the transfer case comprises a spur gear set having three or an odd number of spur gears, wherein the first outlet of the transfer case is formed by a first spur gear and the second outlet of the transfer case is formed by a second or further spur gear which is driven in the same direction of rotation as the first spur gear.

In the case of the power plant transmission line according to the first embodiment with a transmission with a variable speed, the transfer case preferably comprises at least one inlet which forms the inlet of the transmission with a variable speed or is connected in a rotationally fixed manner at least indirectly to the inlet of the transmission with a variable speed. The transfer case comprises at least two outlets which are arranged eccentrically with respect to each other, wherein a first outlet is connected at least indirectly to the pump impeller of the hydrodynamic coupling and a second outlet is connected at least indirectly to the pump impeller of the hydrodynamic speed/torque converter. A torque transmission to the individual hydrodynamic component and thus to the power branch is thereby achieved.

According to one development, the inlet of the speed-adjustable transmission and the first outlet of the transfer case are arranged coaxially with respect to one another, wherein preferably the first outlet is coupled to a hydrodynamic speed/torque converter which can thus be loaded with the same rotational speed as the inlet. The fluid coupling is then connected to an outlet arranged eccentrically with respect to the inlet of the transfer case, wherein the coupling between the inlet and the outlet is preferably realized by a transmission ratio which leads to a reduction in speed. This avoids excessively high circumferential speeds at the switch-on device or at the ring gear of the rotary drive. Embodiments in which the inlet and the individual power branches are arranged eccentrically are likewise conceivable.

In an advantageous development, the inlet of the transfer case, which at the same time forms the inlet of the speed-adjustable transmission, is preferably arranged eccentrically with respect to the two power branches. The connection to the power branch is made via a transmission ratio which leads to an acceleration.

There are many possibilities for the design of the transfer gear itself. Preferably, the transfer case is designed as a spur gear set with an odd number of spur gears.

In a first embodiment of the variable-speed transmission having two eccentrically arranged power branches, the pump impeller of the hydrodynamic coupling is connected at least indirectly, preferably directly or via a further transmission device, to the inlet of the variable-speed transmission, in this case to the spur gear set, and the turbine impeller is connected at least indirectly to the outlet of the variable-speed transmission, in this case via the superposition transmission. The pump impeller of the hydrodynamic speed/torque converter is coupled at least indirectly to the inlet of the speed-adjustable transmission, and the turbine impeller is coupled at least indirectly to the outlet via the superposition transmission.

As a type of converter used in both implementations, a co-rotating converter with an adjustable pump impeller and/or guide wheel is preferably used. In the case of a reversing converter, the transfer case can be reduced to an even number of spur gears, and in particular an embodiment with two spur gears is sufficient.

According to a particularly advantageous embodiment, the superposition transmission is arranged coaxially with respect to a common shaft of the two power branches, in particular with respect to a common shaft of the two hydrodynamic components in the first embodiment. Preferably, the arrangement according to the first embodiment is realized coaxially with respect to the first power branch, i.e. coaxially with respect to the mechanical feedthrough or the fluid coupling, in particular coaxially with respect to the turbine wheel of the fluid coupling. The coupling to the hydrodynamic speed/torque converter, which is arranged eccentrically with respect to the hydrodynamic coupling, in particular to the turbine wheel, is in the simplest case realized by a single-stage spur gear. Other embodiments are also contemplated.

According to a second alternative embodiment, it is conceivable that the superposition transmission is arranged coaxially with respect to the second power branch, in particular coaxially with respect to the hydrodynamic rotational speed/torque converter.

The individual arrangement possibilities are primarily relevant here for the design of the superposition transmission. In the simplest case, the superposition transmission comprises only one planetary gear train, which comprises at least one first element in the form of a ring gear, a second element in the form of a planet carrier and a third element in the form of a sun gear, wherein the sun gear is coupled to or forms the outlet of the power transmission device. The first variant is particularly advantageous, in particular in the case of a hydrodynamic coupling coupled with a ring gear, since the coupling with the ring gear can be realized in a simple manner and method, while at the same time the connection of the hydrodynamic speed/torque converter to the carrier can be realized by means of a single-stage spur gear.

In an alternative embodiment with a coaxial arrangement with respect to the hydrodynamic speed/torque converter, the drive can also be realized with the ring gear by only one respective transmission ratio, although here again a single-stage connection of the planet carrier is realized.

If the superposition transmission comprises at least one planetary gear train with a first element which is connected at least indirectly to the turbine wheel of the hydrodynamic coupling, a second element which is coupled at least indirectly to the turbine wheel of the hydrodynamic speed/torque converter, and a third element which is connected at least indirectly to or forms the outlet of the speed-adjustable transmission, then in a particularly advantageous arrangement the first element of the planetary gear train is formed by the ring gear of the planetary gear train, the second element by the planet carrier of the planetary gear train, and the third element by the sun gear of the planetary gear train.

In a particularly advantageous embodiment of this embodiment, it is provided that the braking device is arranged downstream of the hydrodynamic speed/torque converter and upstream of the superposition transmission in the force flow between the inlet and the outlet. This makes it possible to mount the elements when the superimposed transmission is designed as a planetary gear. In the first embodiment, the braking is in particular active when the switching device is open and the converter is empty, i.e. in the adjustment region of the coupling.

The braking device used in the first embodiment can be implemented in different types. The brake device functions as a stopping device. The shut-off device is advantageously designed as a hydraulic brake device. The braking device comprises a rotor which can be coupled to the turbine wheel of the converter, and a stator which is mounted on a stationary component, in particular a housing. This embodiment allows frictionless braking and also allows the use of the same operating medium supply system as in the converter and/or the fluid coupling. Hydrodynamic braking devices also offer the advantage of a low overall size.

An alternative embodiment is that the braking device is designed as a mechanical braking device, in particular as a disc braking device, for example as a disc friction brake. The operation of the braking device may be achieved mechanically, hydraulically, pneumatically, electrically or by a combination of the above. In hydraulic operation, the operating medium of the hydraulic element is used as pressure medium. Other embodiments of the braking device are also conceivable.

In an advantageous development, preferably in addition to the above-mentioned measures, a securing device is provided between the superimposed transmission and the braking device, which securing device comprises a locking device for overcoming the rotational lock. In the simplest case, this is designed as a mechanical locking device which stops the shaft relative to a fixed component, for example a housing.

In an embodiment, it is conceivable for the two basic embodiments to provide a second converter with different converter characteristics in the second power branch. The advantage is that the efficiency of the first converter, which is reduced in the speed range, is increased.

Drawings

The technical solution according to the present invention is explained below with reference to the accompanying drawings. The specific formula is as follows:

fig. 1 is a schematic, simplified, partial illustration of a power plant drive train having a speed-adjustable transmission with two eccentrically arranged power branches according to a first embodiment;

FIG. 2 is an extension of FIG. 1;

FIG. 3 is a schematic, simplified, partial illustration of a power plant drive train having a speed-adjustable transmission with two eccentrically arranged power branches according to a second embodiment;

fig. 4 is an example of an advantageous design of a gear coupling in the form of a double gear coupling.

Detailed Description

Fig. 1 to 3 each show in a schematic simplified illustration a detail of a power plant drive train 1 in the form of a so-called main turbine drive for driving a variable-speed pump 4, in particular a boiler feed water pump, having two embodiments in the form of a speed-adjustable transmission 5 arranged in a power train between a turbine and the variable-speed pump 4. The power plant drive train 1 comprises at least one turbine, in particular a steam turbine 2 and/or a gas turbine, which is operated at a constant rotational speed and which can be connected or connected to an electrical machine, in particular a generator 3. In the drive connection between the turbine and the variable-speed pump 4, a power transmission device is arranged which is designed as a variable-speed transmission 5 comprising at least one inlet E, an outlet a and a power branch with at least one first power branch 6, also referred to as the main branch, and a hydraulic second power branch 7, wherein the drive power is branched off from the first power branch 6 by means of the hydraulic power branch 7 and is rotationally variably re-input to the second power branch 7 on the drive output side by means of a superposition transmission 8.

The variable speed pump 4 is connected at least indirectly, i.e. directly or via a transmission element, such as a coupling, to the outlet a of the variable speed transmission 5. The connection between the turbine, in this case the steam turbine 2, and the variable-speed transmission 5 is designed with an axial length compensation 10. For this purpose, a connecting device 9 with an axial length compensation 10 is provided in the connecting section. The preset length offset 10 amounts to a range of 10 to 50cm, preferably 10 to 30 cm. The coupling device 9 is designed as a tooth coupling 11, in particular as a circular-arc tooth coupling. A particularly advantageous and simple embodiment of the toothed coupling 11 and which is robust for the conditions of use is shown in fig. 4 in the form of a double-toothed coupling. The toothed coupling can be installed in any connection between the turbine and the speed-adjustable gearbox 5. The tooth coupling 11 comprises a central support, in particular a support cage 12. Which in the mounted position extends in the longitudinal direction of the power station drive line 1. For coupling to the connecting elements, in particular the steam turbine 2 and the speed-adjustable transmission 5,

regions

13, 14 with gears are provided on the support bell 12, which regions are designed as flanges in the illustrated case, which are formed integrally with the support bell 12. Said regions are each arranged in an axial end region of the bearing shell 12. The flange has a toothing on the outer diameter, which is designed as a cylindrical toothing in the illustrated case. The individual toothed elements extend axially and parallel to a central axis M of the bearing shell 12, which in the installed position coincides with the axis of rotation of the bearing shell 12. The counter-element or connecting element which can be brought into engagement with the toothing of the

toothed regions

13, 14 and which has the toothing can be formed either directly by the inlet E of the turbine or the speed-adjustable transmission 5 or by a connecting element which can be connected to this region and which has the toothing. In the case shown, the respective connecting elements are each formed, for example, by a connecting

flange

15 and 16 with a spherical internal toothing.

The power plant transmission line 1 shown in fig. 1 and 2 comprises a rotationally adjustable transmission 5, which transmission 5 has two eccentrically arranged

power branches

6, 7 according to a first embodiment. A hydrodynamic coupling 17 and a hydrodynamic speed/torque converter (hereinafter simply referred to as converter 18) are arranged between the inlet E and the outlet a of the speed-adjustable transmission 5. A fluid coupling 17 is arranged in the first power branch 6 and a converter 18 is arranged in the second power branch. The

respective power branch

6, 7 is connected via a transfer case 20 to the inlet E of the speed-adjustable transmission 5. The

power branches

6, 7 merge via a superposition transmission 8. The transfer case 20, the superposition transmission 8 and the two

power branches

6, 7 are arranged in the housing 19.

The fluid coupling 17 comprises at least one pump impeller P₁₇And a turbine wheel T₁₇. The fluid coupling 17 is equipped with means for engaging or bridging the fluid coupling 17. This device can in the simplest case be a so-called shunt coupling K1. However, the bridging may also be implemented in other ways. The bridging can be provided directly between the pump wheel and the turbine wheel or by means of a component which connects the pump wheel and the turbine wheel in a rotationally fixed manner.

The hydrodynamic converter 18 comprises at least one pump impeller P₁₈Turbine wheel T₁₈And at least one guide wheel L₁₈. The hydrodynamic converter 18 is used here for speed and torque conversion, while the hydrodynamic coupling 17 has the function of a speed converter only. The power transmission via the two

power branches

6, 7 can in this case be carried out independently of one of the

power branches

6, 7 or in a power branch via both power branches.

Pump impeller P of the respective fluid coupling 17₁₇And a pump impeller P of the hydraulic power converter 18₁₈At least indirectly, i.e. directly or via a transmission element, is coupled to the inlet E of the speed-adjustable transmission 5. The coupling here represents a functional connection which can be established from the inlet E of the power transmission device to the pump impeller P of the respective hydrodynamic coupling₁₇Or the pump impeller P of a hydrodynamic converter₁₈The rotationally fixed connection between the two elements is formed either by an intermediate transmission element with or without rotational speed/torque conversion. In order to couple the two hydraulic elements to the inlet E, a transfer case 20 is provided, which is arranged upstream of the two

hydraulic elements

17 and 18, viewed in the force flow between the inlet and the outlet E, A. The transfer case 20 comprises at least one inlet 21, which inlet 21 can be formed by an inlet of the speed-adjustable transmission 5 or can also be coupled to an inlet of the speed-adjustable transmission. The transfer case 20 furthermore comprises at least two outlets, a first outlet 22 connected to the hydrodynamic coupling 17 and a second outlet connected at least indirectly to the hydrodynamic converter 18A second outlet 23. Turbine wheel T of fluid coupling 17₁₇Or turbine wheel T of the hydrodynamic converter 18₁₈The coupling to the output a of the speed-adjustable transmission 5 is effected by a superposition transmission 8. For this purpose, the superposition transmission comprises two

inlets

24 and 25, of which the first inlet 24 is connected to the turbine wheel T of the hydrodynamic coupling 17₁₇And the second inlet 25 is connected to the turbine wheel T of the hydrodynamic converter 18₁₈Are connected. The superposition transmission 8 furthermore comprises at least one outlet 26, which is either formed by the outlet a of the speed-adjustable transmission 5 or is an outlet of the speed-adjustable transmission, or is connected to the outlet of the speed-adjustable transmission, i.e. at least indirectly or directly.

The fluid coupling 17 is designed as an adjustable coupling. The adjustable coupling is provided with an adjustment device 28. Depending on the embodiment of the coupling, it may also relate to an adjustable dip tube, for example.

In the case shown, the transfer case 20 is designed, for example, as a spur gear drive, which comprises an even number of spur gears in order to achieve rotational isotropy between the power branches and a reversal of the rotational direction between the inlet E and the power branches. The outlet a of the speed-adjustable transmission 5 is arranged coaxially with respect to one of the hydrodynamic elements, in the illustrated case with respect to the hydrodynamic coupling 17, in particular the turbine wheel T of the hydrodynamic coupling 17₁₇Are arranged coaxially.

The superposition transmission 8 comprises at least one planetary gear train or planetary gear train 27. The first element 29 of the planetary gear train is here connected to the turbine wheel T of the hydrodynamic coupling 17₁₇The coupling is preferably connected directly in a rotationally fixed manner. Other embodiments are also contemplated. The other second element 30 of the planetary gear 27 is at least indirectly connected to the turbine wheel T of the hydrodynamic converter 18₁₈Connected to one another, and the third element 31 of the planetary gear 27 is connected to or directly forms the outlet a of the speed-adjustable transmission 5. In the case shown, the first element 29 of the planetary gear 27 is formed by a ring gear, while the second element 30 is formed by a planet carrier and the third element 31 is formed by a sun gear. The ring gear and the planet carrier form a

superpositionThe inlets

24 and 25 of the transmission 8 are either directly connected to the

inlets

24 and 25 of the superimposed transmission, while the sun wheel forms the outlet 26 of the superimposed transmission 13. The coupling of the planet carrier to the second power branch 7 is effected here by connecting the transmission 32, in the simplest case by a single-stage spur gear which implements the turbine wheel T of the hydrodynamic converter 18₁₈And the direction of rotation between the inlet 25 is reversed.

The fluid coupling 17 and the device, in particular the branching coupling K1 and the adjusting device 28, form a so-called starting unit and/or adjusting unit. The filling of the fluid coupling 17 is performed for starting and/or adjustment. The turbine wheel T can be adjusted by the adjusting device 28₁₇The output rotational speed of (1). When a specific rotational speed, in particular a synchronous rotational speed, is reached, the device K1 for the shift and thus for the mechanical feedthrough is connected between the inlet E and the superposition transmission 8. A constant torque is thus transmitted purely mechanically via the power branch 6 containing the hydrodynamic coupling 17. The power fraction guided by the hydrodynamic converter 18 is fed to the superposition transmission 8 via the coupling transmission 32. As with the transducer 18, the slave pump impeller P is typically formed₁₈Passing at least one guide wheel L₁₈To the turbine wheel T₁₈The working medium stream of (2). In parallel therewith, power is transferred mechanically from the input shaft E via the transfer case 20 and the direct coupling by the device K1. The two

power branches

6, 7 are then recombined via the planetary gear train 27 of the superposition transmission 8 and fed into the outlet a.

In order to ensure the support of the planet carrier of the summation transmission 8 in the operating region in which the converter 18 is emptied, a brake device 33 is arranged downstream of the converter 6, which brake device 33 is preferably designed as a hydraulic brake device. The braking device comprises a stator S mounted on a stationary component, in particular a housing 19, and a turbine wheel T₁₈A rotor R connected in a rotationally fixed manner.

Fig. 2 furthermore shows a further hydrodynamic converter 34 in the second power branch 7. The other hydraulic converter comprises at least one pump impeller P₃₄Turbine wheel T₃₄And a guide wheel L₃₄. Second hydraulic force in the second power branch 7The converter 34 is designed such that it has a different conversion characteristic than the first converter 18. This has the advantage that the efficiency of the first converter 18, which is reduced in the rotational speed range, is increased. The second converter 34 is arranged coaxially with respect to the first converter 18 for this purpose, and the pump impeller P₃₄Is coupled at least indirectly to the inlet E. Preferably, the pump impeller P of the first converter 18₁₈And the pump impeller P of the second converter 34₃₄Are arranged on a common shaft. The pump impeller passing through the corresponding turbine wheel T₁₈Or T₃₄Is guided by the connecting shaft. Preferably, the turbine wheels are non-rotatably connected to a common shaft 36.

Furthermore, a device 36 for braking and/or locking the inlet 15 of the superposition transmission 13, which can be connected to the fluid coupling 4, is arranged downstream of the fluid coupling 17 in the first power branch 6, as seen in the force flow from the inlet E to the outlet a, for example. An additional brake 36 is arranged in the first power branch 6 at the turbine wheel T of the hydrodynamic coupling 17₁₇And the superposition transmission 8, and is only schematically shown here. The stopper 36 may be variously formed. Hydraulic brakes or mechanical braking devices are conceivable.

Fig. 3 shows an embodiment according to a second embodiment in a schematic simplified diagram, wherein the power branch 6 is designed as a purely mechanical power branch with a mechanical feedthrough. In this power branch line, the fluid coupling according to fig. 1 and 2 in the first power branch line 6 is not present, and the braking device 33 is not present in the second power branch line. Otherwise the basic structure is comparable to the embodiment in fig. 1 and 2, and therefore the same reference numerals are used for the same elements.

The embodiment according to fig. 1 and 2 has a gear ratio which leads to acceleration, and the embodiment according to fig. 3 has a gear ratio which leads to deceleration, in particular at a drive speed of 3000 rpm. In other applications, it is also conceivable to provide a gear ratio which leads to a deceleration for the respective embodiment according to fig. 1 and 2 and an acceleration for the embodiment according to fig. 3. In addition, in other applications for the embodiment according to fig. 1 and 2, the inlet of the transfer case can also be arranged coaxially with respect to one of the two power branches.

In all the embodiments shown, the connecting device 9 is preferably designed as a tooth coupling, in particular as a double tooth coupling.

Claims

1. A power station transmission line with

-a steam turbine (2) and/or a gas turbine operating at a constant rotational speed for driving an electric generator (3);

-a variable-speed pump for conveying and/or compressing a working medium for driving and/or process-supplying the steam turbine (2) and/or the gas turbine or for conveying and/or compressing an exhaust gas formed in the process-supplying or the gas turbine, wherein the variable-speed pump is driven by means of the steam turbine (2) and/or the gas turbine, and

-arranging a power transmission device designed as a speed-adjustable transmission (5) in the drive connection, which power transmission device comprises at least one inlet (E), an outlet (a) and a power branch with at least one first power branch (6) and a hydraulic second power branch (7), wherein the drive power is branched off from the first power branch (6) by means of the hydraulic power branch (7) via a hydrodynamic coupling or hydrodynamic converter (18) and is input into the first power branch (6) in a variable speed ratio on the drive output side by means of the superposition transmission (8);

characterized in that the steam turbine (2) and/or the gas turbine is connected to the power transmission system via a connecting device (9) having an axial length compensation (10).

2. The power plant transmission line (1) according to claim 1, characterized in that the axial length compensation (10) of the connecting device (9) amounts to the range of 10 to 50 cm.

3. The power plant transmission line (1) according to claim 1 or 2, characterized in that the connecting device (9) is configured as a tooth coupling (11).

4. The power plant drive line (1) according to claim 3, characterized in that the tooth coupling (11) comprises a support element (12) having a dimension in the axial direction, which in the first configuration has at least one toothed region (13), which at least one toothed region (13) meshes with at least one tooth on a connecting element, which is coupled to or formed by a turbine (2) and/or a speed-adjustable transmission (5), or which is coupled to or formed by a turbine and/or a speed-adjustable transmission

The toothed coupling (11) is designed as a double-toothed coupling comprising a carrier element (12) having an axial dimension, which has two toothed regions (13, 14), which are each arranged in a respective axial end region of the carrier element (12), wherein the teeth each mesh with a toothing on a connecting element that is coupled to or formed by a turbine (2) or a transmission (5) with a variable speed.

5. The power plant transmission line (1) according to claim 1,

-the first and second power branches (6, 7) are arranged parallel or eccentric to each other;

-the first and second power branch (6, 7) are each connected to the inlet (E) of the speed-adjustable transmission (5) via a transfer case (20) arranged in the housing (19);

-the first power branch (6) is configured as a mechanical feed-through without hydraulic components;

-the second power branch (7) comprises in the first configuration only one hydraulic speed/torque converter (18) with at least one pump impeller (P)₁₈) Turbine wheel (T)₁₈) And a guide wheel (L)₁₈) Or is or

In addition to having at least one pump impeller (P) in the second configuration₁₈) Turbine wheel (T)₁₈) And a guide wheel (L)₁₈) In addition to the first hydraulic speed/torque converter (18), also comprises-including a further second hydraulic speed/torque converter (34), which second hydraulic speed/torque converter (34) is arranged coaxially with respect to the first hydraulic speed/torque converter (18), wherein the second hydraulic speed/torque converter (34) has a different conversion characteristic than the first hydraulic speed/torque converter (18);

-each speed/torque converter (18, 34) can be applied in a different operating region.

6. The power plant transmission line (1) according to claim 4,

-arranging in the first power branch (6) at least one pump impeller (P)₁₇) Turbine wheel (T)₁₇) And a fluid coupling (17) for a bridging device (K1);

-arranging at least one pump impeller (P) in the second power branch₁₈) Turbine wheel (T)₁₈) And a guide wheel (L)₁₈) Wherein the two power branches (6, 7) can be connected to the outlet (A) via a superposition transmission (8);

the hydrodynamic rotational speed/torque converter (18) and the hydrodynamic coupling (17) are arranged eccentrically to one another, parallel to one another, and can each be connected to the inlet (E) of the speed-adjustable transmission (5) via a transfer case (20) arranged in the housing (19) in such a way that two power branches (6, 7) are formed.

7. The power plant drive line (1) according to claim 5 or 6, characterized in that the superposition transmission (8) is arranged coaxially in the first or second power branch (6, 7) and the respective other power branch (7, 6) is coupled to the superposition transmission (8) by means of a connecting transmission (32).

8. The power plant transmission line (1) according to claim 7,

-the superposition transmission (8) comprises at least one planetary gear train (27);

-the planetary gear train (27) comprises a first element (29) which is arranged coaxially in the first power branch (6) with respect to and connected to a torque-transmitting component, i.e. a turbine wheel (T17) of the fluid coupling (17) or a shaft in the purely mechanical through-going case;

-the planetary gear train (27) comprises a second element (30) at least indirectly associated with a turbine wheel (T) of a hydrodynamic speed/torque converter (18)₁₈) Is coupled in the second power branch (7);

-the planetary gear (27) comprises a third element (31) which is at least indirectly connected to or constitutes an outlet (a) of the adjustable speed transmission (5).

9. The power plant drive line (1) according to claim 6, characterized in that a further second hydrodynamic speed/torque converter (34) is provided in the second power branch (7), which second hydrodynamic speed/torque converter is arranged coaxially with respect to the first hydrodynamic speed/torque converter (18), wherein the second hydrodynamic speed/torque converter (34) has a different conversion characteristic than the first hydrodynamic speed/torque converter (18) and each speed/torque converter (18, 34) can be applied to a different operating region.

10. The power plant transmission line (1) according to claim 5 or 9, characterized in that the first and second hydrodynamic speed/torque converters (18, 34) each comprise at least one pump impeller (P)₁₈、P₃₄) Turbine wheel (T)₁₈、T₃₄) And a guide wheel (L)₁₈、L₃₄) Wherein the turbine wheels (T) of the first and second hydrodynamic speed/torque converters (18, 34)₁₈、T₃₄) Are connected to each other by a hollow shaft (36), and the hollow shaft (36) is connected to the superimposed transmission (8) by a connecting transmission (32)) Is connected to or forms the inlet (25) of the superposition transmission (8).

11. The power station transmission line (1) according to claim 6, characterized in that a braking device (33) for braking/locking the turbine wheel of the converter (18) is provided in the second power branch (7).

12. The power plant transmission line (1) as claimed in claim 1, characterized in that the transfer case (20) comprises at least one inlet (21) which forms or is at least indirectly connected in a rotationally fixed manner to an inlet (E) of the speed-adjustable transmission (5), and the transfer case (20) comprises at least two outlets (22, 23) which are arranged eccentrically to one another, wherein a first outlet (22) can be connected at least indirectly to the first power branch (6) and a second outlet (23) can be connected to a pump impeller (P) of the hydrodynamic speed/torque converter (18)₁₈) At least indirectly, wherein the inlet (21) of the transfer case (20) is arranged coaxially or eccentrically with respect to the inlet of one of the power branches (6, 7).

13. The power plant transmission line (1) according to claim 1, characterized in that the transfer gear (20) is designed with a speed-reducing transmission ratio or a speed-accelerating transmission ratio for the first and/or second power branch (6, 7).

14. The power plant transmission line (1) according to claim 1, characterized in that the hydrodynamic converter (18) is designed as a reversing converter and the transfer case (20) comprises a spur gear set with two or an even number of spur gears, wherein the first outlet (22) of the transfer case (20) is formed by a first spur gear and the second outlet (23) of the transfer case (20) is formed by a second spur gear or other spur gear which is driven in the opposite direction to the direction of rotation of the first spur gear.

15. The power plant transmission line (1) according to claim 1, characterized in that the hydrodynamic converter (18) is designed as a converter in the same direction and the transfer case (20) comprises a spur gear set with three or an odd number of spur gears, wherein the first outlet (22) of the transfer case (20) is formed by a first spur gear and the second outlet (23) of the transfer case (20) is formed by a second or further spur gear which is driven in the same direction of rotation as the first spur gear.

16. The power plant transmission line (1) according to claim 1, characterized in that the variable speed pump is a boiler feed water pump.

17. The power plant transmission line (1) according to claim 1, characterized in that the axial length compensation (10) of the connecting device (9) amounts to the range of 10 to 30 cm.

18. The power plant transmission line (1) according to claim 1 or 2, characterized in that the tooth coupling (11) is a circular arc tooth coupling.