Bearing lubrication of a shaft turbine by means of natural pressure difference

Abstract

The invention relates to a turbine generator device (2) comprising an annular housing (6) with a bearing device (12), an annular generator (15), and a turbine impeller (10) coupled for conjoint rotation to a turbine shaft (14). The bearing device (12) comprises a first axial plain bearing (26), a second axial plain bearing (27) and a first radial plain bearing (28a), wherein a turbine shaft (14) oriented along the axis of rotation (11) of the turbine is mounted by means of the plain bearings (26, 27, 28). A filtering and conveying device (30) for the cooling and lubricating liquid to be fed to the plain bearings (26, 27, 28) is formed at a first axial end face (29) of the bearing device (12). The cooling and lubricating liquid can flow sequentially through a first bearing gap space (31) of the first axial plain bearing (26), thereafter through a second bearing gap space (32) of the second axial plain bearing (27) and thereafter through a third bearing gap space (33) of the first radial plain bearing (28a), wherein the cooling and lubricating liquid is able to flow into a collecting chamber (35) located or mounted downstream of the plain bearings (26, 27, 28) along the flow path (34) of the cooling and lubricating liquid.

Description

[0001] Bearing lubrication of a shaft turbine using natural pressure difference

[0002] The invention relates to a turbine generator device for generating electricity by converting the energy of a discharge between an upstream and downstream watercourse. The turbine generator device comprises a bearing device with plain bearings and a filter and conveying device for the cooling and lubricating fluid to be supplied to the plain bearings. Related documents are known from the prior art.

[0003] EP2250367B 1, for example, shows a tubular turbine generator unit comprising a turbine runner, a drive shaft which is rotationally rigidly connected to the turbine runner, an electric generator with a generator rotor and a generator stator, wherein the generator rotor is driven at least indirectly by the drive shaft, a tubular turbine housing which encloses the electric generator, a bearing arrangement which is arranged within the tubular turbine housing and which serves to support the drive shaft, a floodable spatial area in the interior of the tubular turbine housing which is flooded with water during operation of the tubular turbine generator unit, wherein the generator gap between the generator rotor and the generator stator and the bearing gap of the bearing arrangement are part of the floodable spatial area.

[0004] Furthermore, DE102009021289A1 shows a bearing arrangement, comprising a bearing through which a medium, in particular water, flows, a shaft which is accommodated in the bearing, a filter device which is arranged upstream of the bearing on the inflow side and which removes particles from the medium, wherein the filter device comprises a protective cap and a fine filter, wherein the protective cap is arranged upstream of the fine filter on the inflow side, and a conveying device for the medium which is arranged between the protective cap and the fine filter.

[0005] The designs of bearing arrangements known from the prior art describe only partially satisfactory solutions, particularly for the use of turbine generator devices with a ring generator in a shaft power plant.

[0006] The object of the present invention was to overcome the disadvantages of the prior art and to provide a turbine generator device with a bearing device, by means of which bearing device on the one hand a particularly uniform flow through the plain bearings is ensured and on the other hand the design effort and the necessary auxiliary elements and means of the turbine generator device are reduced.

[0007] This object is achieved by a device according to the claims.

[0008] The turbine generator device according to the invention for generating electricity by converting the energy of an outflow between an upstream water body with an upstream water level and a downstream water body with a downstream water level in a shaft power plant with an intake basin comprises an annular casing with an inlet area and an outlet area, a ring generator, and a turbine runner with a turbine rotation axis. The annular casing comprises, in the inlet area, a pear-shaped bearing device aligned along the turbine rotation axis, wherein the bearing device is fixedly mounted on the annular casing by means of at least one connecting element.The bearing device comprises a first hydrodynamic axial plain bearing, a second hydrodynamic axial plain bearing spaced apart from the first axial plain bearing in the direction of the turbine's rotational axis, and a first hydrodynamic radial plain bearing. A turbine shaft aligned along the turbine's rotational axis is supported by the plain bearings. The turbine impeller is rotationally fixedly coupled to the turbine shaft in the outlet region. At a first axial end of the bearing device or in the inlet region, the bearing device comprises a filter and conveying device for the cooling and lubricating fluid to be supplied to the plain bearings.

[0009] A first bearing gap of the first axial plain bearing, subsequently a second bearing gap of the second axial plain bearing and subsequently a third bearing gap of the first radial plain bearing can be flowed through sequentially, or serially or in series by the cooling and lubricating fluid, wherein the cooling and lubricating fluid can flow into a collecting chamber following or downstream of the plain bearings along the flow path of the cooling and lubricating fluid.

[0010] The turbine shaft has, at least in sections, at least one flow channel oriented substantially parallel to the turbine rotation axis. The flow channel can be fluidically coupled to the operating medium flowing through the turbine generator device in the outlet region of the turbine generator device or in the region of the coupling of the turbine shaft to the turbine runner, so that the cooling and lubricating fluid, viewed in the flow direction through the turbine generator device, is transferred from the turbine runner to the outflow of the shaft power plant. For this purpose, the turbine shaft has a connecting channel that can be fluidically coupled to the flow channel and the collecting chamber, allowing the cooling and lubricating fluid to flow through the bearing device.

[0011] This allows the bearing device, or all of the bearing device's plain bearings, to be permeated by cooling and lubricating fluid. The cooling and lubricating fluid can be directed through the bearing gaps of the plain bearings due to the pressure difference between the inlet and outlet areas, either naturally occurring or caused by the design of the shaft power plant and the turbine-generator system. The advantage here is that utilizing the natural pressure difference between the inlet and outlet areas, or between upstream and downstream of the turbine-generator system, enables a simple design of the bearing device, thus avoiding the need for additional auxiliary units to provide the cooling and lubricating fluid.In addition to the obvious economic advantages in the manufacture and operation of the turbine generator device, the simplified structural design also improves the service life and stability of the turbine generator device.

[0012] Furthermore, it may be advantageous for the flow channel to be designed along the turbine's rotational axis and rotationally symmetrical to the turbine's rotational axis. Furthermore, it may be advantageous for several connecting channels to be provided distributed around the circumference of the turbine shaft. This allows the turbine shaft to be designed as a hollow shaft, at least in sections, to centrally drain the cooling and lubricating fluid from the collecting chamber. This enables the most homogeneous pressure distribution of the cooling and lubricating fluid in the bearing gaps in the circumferential direction, which leads to an improved service life and wear resistance of the plain bearings.

[0013] Furthermore, it can be provided that the flow channel in the outlet area includes a throttle element and / or a diffuser element. If the turbine generator device is used with essentially the same design for different head heights or flow rates at, for example, different locations, a counterpressure can be adjusted in the flow channel using the throttle element and / or the diffuser element, so that the pressure difference of the cooling and lubricating fluid between the filter and conveying device and the flow channel can be adjusted to achieve advantageous cooling and sufficient lubrication of the plain bearings.

[0014] Furthermore, it can be provided that several connecting channels are arranged distributed in the circumferential direction, each of which can be fluidically coupled to the flow channel. This allows the pressure distribution in the bearing gap spaces to be homogenized, since the circumferentially distributed connecting channels promote a uniform outflow of the coolant and lubricant from the collecting space into the flow channel.

[0015] Also advantageous is a configuration in which several flow channels are formed distributed in the circumferential direction, and several connecting channels are formed distributed in the circumferential direction, each of which can be fluidically coupled to a flow channel. In other words, a configuration is conceivable in which not one central flow channel is provided, but in which several flow channels can be provided, each of these flow channels having a connecting channel to the collecting chamber. As a result, the turbine shaft does not have to be designed in sections as a hollow shaft with a central flow channel; instead, the individual flow channels distributed in the circumferential direction can be produced as individual bores.This can positively influence the strength of the turbine shaft and, if necessary, allow the turbine shaft to have a smaller maximum outer diameter than with a hollow shaft design. At the same time, the circumferentially distributed flow channels and their associated connecting channels promote a uniform outflow of coolant and lubricant from the collection chamber.

[0016] According to a further development, it is possible for the bearing device to comprise a second hydrodynamic radial plain bearing axially spaced from the first radial plain bearing in the flow direction, wherein the second radial plain bearing comprises a fourth bearing gap, wherein the cooling and lubricating fluid can flow into a collecting chamber following or downstream of the plain bearings along the flow path of the cooling and lubricating fluid. By providing a second radial plain bearing, which is arranged axially spaced from the first radial plain bearing, the deflection of the turbine shaft can be reduced, which leads to a more homogeneous flow of cooling and lubricating fluid through the bearing gaps of all plain bearings. This, in turn, increases the service life and the maintenance intervals of the turbine-generator device.

[0017] Furthermore, it may be expedient if a second cooling and lubricating fluid inlet is formed in the region of the coupling of the turbine shaft to the turbine impeller, wherein the fourth bearing gap space can be fluidly coupled to the second cooling and lubricating fluid inlet and the collecting chamber, such that the fourth bearing gap space can be flowed through by means of the second cooling and lubricating fluid inlet with cooling and lubricating fluid taken from the operating medium flowing through the turbine generator device during operation. It is advantageous in this case that, in particular if the natural pressure difference between the inlet and outlet regions is too low or if the throttling effect of the first, second and third bearing gap spaces is too high, the second radial plain bearing can be supplied with cooling and lubricating fluid by means of the second cooling and lubricating fluid inlet independently of the remaining plain bearings.This allows the plain bearings of the bearing device to be operated in an advantageous and gentle manner, particularly when the turbine generator device is used at low head heights.

[0018] Furthermore, it can be provided that the fourth bearing gap of the second radial plain bearing can be flowed through sequentially or in series or serially following the third bearing gap by the cooling and lubricating fluid, which can be extracted from the operating medium of the turbine-generator device by means of the filter and conveying device. It is advantageous in this case that the entire quantity of cooling and lubricating fluid is provided by the filter and conveying device, and thus possible contamination of the cooling and lubricating fluid can be influenced centrally at a component or in an area of ​​the turbine-generator device. With careful design of the filter and conveying device, the service life and maintenance intervals of the turbine-generator device and also the service life of the plain bearings can be significantly improved.

[0019] Furthermore, it can be provided that the filter and conveying device comprises a cover plate that is coupled to the turbine shaft in a rotationally fixed manner, wherein a first cooling and lubricating fluid inlet is formed between the cover plate and the bearing device, and wherein the cover plate and / or the bearing device has, in the region of the cover plate, at least one groove, a channel, a wiper, a rubber lip or a similar guide element in the first cooling and lubricating fluid inlet, starting from a first radial distance in the direction of a second radial distance that is greater than the first radial distance. It can therefore be advantageous if, for example, a recess is provided on the cover plate or on the bearing device in the region of the cover plate in the region of the first cooling and lubricating fluid inlet, which recess extends from the inside to the outside in the radial direction relative to the turbine rotation axis.If the cover plate is rotatably coupled to the turbine shaft, a centrifugal force directed radially outwards relative to the turbine rotation axis is created in the recess or, for example, when a wiper is used, which removes sediments or other contaminants of the operating medium or the cooling and lubricating fluid from the first cooling and lubricating fluid inlet.

[0020] According to a special embodiment, it is possible for the bearing gaps to have flushing grooves, with a first gap width of the first cooling and lubricating fluid inlet being smaller than the depth of the flushing grooves. This makes it easy to prevent clogging of the bearing gaps, which in turn leads to an improved service life of the plain bearings and thus of the entire turbine-generator system. At the same time, this measure is also economically advantageous compared to potentially complex filtration of the cooling and lubricating fluid.

[0021] According to an advantageous development, the filter and conveying device can comprise a conveying element that is rotationally coupled to the turbine shaft, wherein the cooling and lubricating fluid to be supplied to the plain bearings can be conveyed to the first bearing gap. It is also conceivable for the conveying element to be hydraulically coupled to the turbine shaft. The provision of a conveying element has the advantage that the pressure level of the cooling and lubricating fluid to be supplied to the plain bearings can be easily increased. At the same time, the rotationally or hydraulic coupling of the conveying element to the turbine shaft means that no additional auxiliary units are required to provide the required conveying capacity, which improves the economic efficiency of the turbine-generator device.

[0022] In particular, it may be advantageous if the turbine generator device comprises a flow guide device with guide elements, wherein the flow guide device is arranged in the flow direction between the at least one connecting element and the ring generator, wherein the guide elements are each mounted on the one hand on the bearing device by means of a plain bearing, wherein the flow guide device is provided by means of a first adjusting device for actively controlling the flow to the turbine impeller.

[0023] This allows for simpler rotor blade or turbine runner geometries with regard to the hydraulic design of the turbine runner, since the flow guidance device, in conjunction with the turbine runner, enables a hydraulically advantageous design of the hydraulic components. As a result, the design of the turbine generator device can be made more compact with respect to its axial extent, which in turn brings with it various advantages with respect to loads, deflections, and also with respect to the necessary strength of the individual components of the turbine generator device. With respect to the bearing device, the deflections of the turbine shaft can thus be reduced, which subsequently leads to an increased service life of the plain bearings and to the associated advantages already described.

[0024] Furthermore, it can be provided that the turbine-generator unit can be accommodated entirely in the intake basin of the shaft power plant. It is advantageous that the entire turbine-generator unit is surrounded by the operating medium, thus ensuring a sufficient supply of cooling and lubricating fluid to the cooling and lubricating fluid inlets at all times during operation of the turbine-generator unit.

[0025] Furthermore, it can be provided that at least three connecting elements are formed, wherein the bearing device is fixedly mounted on the annular housing by means of the at least three connecting elements. This allows for a particularly stable positioning of the bearing device relative to the annular housing, whereby vibrations induced, in particular, by the turbine impeller or other hydraulic components can be absorbed and damped in an improved manner. With regard to the bearing device, this measure, in turn, improves the service life of the turbine-generator device.

[0026] Another advantageous embodiment is one in which the ring generator of the turbine generator device is designed as a synchronous generator, with permanent-magnetic poles and / or a brushless exciter provided in the ring generator rotor as excitation. This makes the design of the turbine generator device more compact, and the ring generator rotor has a reduced weight, which protects the plain bearings while reducing deflection of the turbine shaft. According to a further development, it is possible for the ring generator to be designed with speed control by means of an electronic control device.Due to the controllability of the speed of the turbine generator device, the turbine generator device can be made more compact in its design due to the simplified hydraulic design of the turbine generator device, which also results in a reduced weight, which protects the plain bearings with less deflection of the turbine shaft.

[0027] Furthermore, it may be expedient for the turbine impeller to have rotatably mounted turbine blades, with the turbine blades being mounted on the ring generator rotor on the one hand and on the bearing device on the other, with the turbine blades being rotatable by means of a second adjusting device. This improves the controllability of the turbine generator device over a wider operating range, which in turn can result in a simplified hydraulic design of the turbine generator device and thus provides or expands the aforementioned advantages.

[0028] Furthermore, the annular housing can be provided with a support device in the inlet area, whereby the turbine generator device can be supported on a floor of the inlet basin by means of the support device. This increases the stability of the turbine generator device, which can have a particularly advantageous effect on the service life of the plain bearings.

[0029] For a better understanding of the invention, it is explained in more detail using the following figures.

[0030] They show in a highly simplified, schematic representation:

[0031] Fig. 1 shows a shaft power plant with a first embodiment of a turbine generator device;

[0032] Fig. 2 Sectional view of the turbine generator device with a possible design of the bearing device.

[0033] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations. The disclosures contained throughout the description can be applied analogously to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and these positional information must be applied analogously to the new position in the event of a change in position.

[0034] Fig. 1 shows a shaft power plant 1 with a possibly independent first embodiment of a turbine generator device 2. The turbine generator device 2 can be designed to generate electricity by converting the energy of an outflow between an upstream water level 3 and a downstream water level 4. The turbine generator device 2 can be arranged in an inlet basin 5 of the shaft power plant 1. The turbine generator device 2 can comprise an annular casing 6 with an inlet region 7 and an outlet region 8, wherein the outflow between the upstream water level 3 or from the inlet basin 5 of the shaft power plant 1 to the downstream water level 4 can be guided in the flow direction 9 through the annular casing 6 and thus through the turbine generator device 2.

[0035] Furthermore, the turbine generator device 2 can comprise a turbine runner 10 with a turbine rotation axis 11. The annular housing 6 can also have a drop-shaped or bevel-shaped bearing device 12 aligned along the turbine rotation axis 11 in the inlet region 7, wherein the bearing device 12 is fixedly connected or held to the annular housing 6 by means of at least one connecting element 13 or preferably four connecting elements 13. The turbine runner 10 can be rotationally fixedly coupled to a turbine shaft 14 aligned along the turbine rotation axis 11, wherein the turbine shaft 14 can be mounted by means of the bearing device 12.

[0036] Furthermore, the turbine generator device 2 can comprise a ring generator 15 with a ring generator stator 16 and a ring generator rotor 17. The ring generator stator 16 can be rotationally fixedly coupled to the ring housing 6 in the outlet region 8, and the ring generator rotor 17 can be rotationally fixedly coupled to the turbine runner 10 at an outer diameter, or to individual rotor blades of the turbine runner 10 at an outer diameter of the turbine runner 10 that is radially spaced from the turbine rotation axis 11, so that the ring generator rotor 17 undergoes a rotation about the turbine rotation axis 11 relative to the ring generator stator 16 during operation of the turbine generator device 2 upon rotation of the turbine runner 10. With regard to the turbine runner 10, it is conceivable that it can have rotatably mounted turbine blades, wherein the turbine blades can be rotatably mounted on the ring generator rotor 17 and on a hub coupled to the turbine shaft 14.

[0037] Furthermore, the ring generator 15 can be designed as a synchronous generator, wherein the ring generator rotor 17 can comprise permanent-magnetic poles and / or a brushless exciter as excitation. Furthermore, the ring generator 15 can be designed to be speed-controlled by means of an electronic control device.

[0038] Furthermore, the turbine generator device 2 can comprise a support element 18 with a connection surface 19. The support element 18 can be arranged downstream of the ring generator stator 16 or the ring generator 15 in the flow direction 9 and can be coupled to the ring generator stator 16 in a rotationally fixed manner. The turbine generator device 2 can thus be mounted on the support element 18. The turbine generator device 2 can be displaceable at least between a maintenance position and an operating position, wherein the turbine generator device 2 is preferably positioned above the underwater level 4 when positioned in the maintenance position, and the turbine generator device 2 is positioned in such a way when positioned in the operating position that the outflow between the upstream and downstream water can be fluidically coupled to the downstream water through the turbine generator device 2 using a suction pipe 20 or a flow channel.When positioning the turbine generator device 2 in the operating position, the support element 18 can be designed such that the connection surface 19 comes into contact with or is pressed against a counter connection surface 21 located, for example, on the structural structure of the shaft power plant 1 or on a wall section of the inlet basin 5 facing the underwater area.

[0039] Furthermore, it can be provided that the turbine generator device 2 comprises a flow guiding device 22 with individual guide elements 23 or with individual guide vanes. The flow guiding device 22 can be arranged downstream of the at least one connecting element 13 or the connecting elements 13 in the flow direction 9. It can be provided that the guide elements 23 extend from the surface of the bearing device 12 to an inner surface of the annular housing 6, wherein the guide elements 23 can be cantilevered on the bearing device 12 and can be mounted on the annular housing 6. The flow guiding device 22 can comprise an adjusting device, such as a regulating ring, by means of which adjusting device the guide elements 23 can be adjusted in order to ensure or enable active control of the flow to the turbine impeller 10.

[0040] It can also be provided that the turbine generator device 2 or the annular housing 6 comprises a support device 24 in the inlet area 7, wherein the turbine generator device 2 can be supported by means of the support device 24 on the bottom 25 of the inlet basin 5.

[0041] Fig. 2 shows a sectional view of the turbine generator device 2 with a possible embodiment of the bearing device 12, wherein the same reference numerals or component designations are used for the same parts as in the previous Fig. 1. To avoid unnecessary repetition, reference is made to the detailed description in the previous Fig. 1.

[0042] As shown in Fig. 2, the bearing device 12 of the turbine-generator device 2 can comprise a first hydrodynamic axial plain bearing 26, a second hydrodynamic axial plain bearing 27, and a first hydrodynamic radial plain bearing 28a. The second axial plain bearing 27 can be arranged at a distance from the first axial plain bearing 26 in the direction of the turbine rotation axis 11. The turbine shaft 14 is supported by the plain bearings 26, 27, 28. The turbine impeller 10 can be rotationally fixedly coupled to the turbine shaft 14.

[0043] Furthermore, the bearing device 12 of the turbine-generator device 2 can comprise a filter and conveying device 30 in the inlet region 7 at a first axial end 29. The filter and conveying device 30 can be configured to extract cooling and lubricating fluid from the operating medium flowing through the turbine-generator device 2 in order to supply this cooling and lubricating fluid to the plain bearings 26, 27, 28. For this purpose, the filter and conveying device 30 can comprise a cover plate 38 that is non-rotatably coupled to the turbine shaft 14, wherein a first cooling and lubricating fluid inlet 39 is formed between the cover plate 38 and the bearing device 12, by means of which cooling and lubricating fluid can be extracted from the operating medium flowing through the turbine-generator device 2 during operation.It can be provided that the cover plate comprises at least one groove, notch, recess, a rubber lip, a wiper or a similar guide element running radially from the inside to the outside with respect to the turbine rotation axis 11, wherein this guide element is formed in the first cooling and lubricating fluid inlet 39 or is formed in such a way that the flow pattern in the first cooling and lubricating fluid inlet 39 can be influenced thereby.

[0044] As can be seen from Fig. 2, the plain bearings 26, 27, 28 can be arranged such that, starting from the filter and conveying device 30, cooling and lubricating fluid flows sequentially or in series through first a first bearing gap 31 of the first axial plain bearing 26, followed by a second bearing gap 32 of the second axial plain bearing 27 and followed by a third bearing gap 33 of the first radial plain bearing 28a.It can be provided that the bearing gap spaces 31, 32, 33 each comprise at least one groove, notch, recess, a rubber lip, a wiper or a similar flushing element, wherein the respective flushing element limits or widens the cross section of the respective bearing gap space 31, 32 or 33 at the formation point of the flushing element in such a way that a first gap width of the first cooling and lubricating fluid inlet 39 is smaller than a cross-sectional dimension in the radial direction of the respective bearing gap space 31, 32 or 33 at the formation point of the flushing element.

[0045] The filter and conveying device 30 can also comprise a conveying element 40 which is coupled to the turbine shaft 14 in terms of rotational energy and / or hydraulically in order to increase the pressure level of the cooling and lubricating fluid received by the first cooling and lubricating fluid inlet 39 and / or to supply the cooling and lubricating fluid to the plain bearings 26, 27, 28 or initially to the first bearing gap 31 and subsequently to the other bearing gaps.

[0046] Furthermore, the bearing device 12 of the turbine-generator device 2 can comprise a collecting chamber 35 for the cooling and lubricating fluid. The collecting chamber 35 can be arranged downstream of the plain bearings 26, 27, 28 with respect to the flow path 34 of the cooling and lubricating fluid. At least one flow channel 36 can be formed in the turbine shaft 14, wherein the at least one flow channel 36 is designed to run substantially in the direction of the turbine rotation axis 11. Furthermore, the flow channel 36 can be formed at least in sections in the turbine shaft 14, wherein the flow channel 36 has an opening 41 at least in the outlet region 8 of the turbine-generator device 2, such that the flow channel 36 can be fluidically coupled to the outlet region 8. Furthermore, a connecting channel 37 can be formed in the turbine shaft 14, wherein the collecting space 35 and the flow channel 36 can be fluidically coupled by means of the connecting channel 37.

[0047] A design form of the turbine-generator device 2 is conceivable in which the turbine shaft 14 comprises a plurality of flow channels 36 which are formed in the turbine shaft 14 essentially parallel to the turbine rotation axis 11, and a connecting channel 37 for each flow channel 36, wherein the flow channels 36 and the respectively associated connecting channels 37 are distributed in the circumferential direction of the turbine shaft 14. A further design form of the turbine-generator device 2 is likewise conceivable in which the turbine shaft 14 comprises a flow channel 36 which is arranged centrally in the turbine shaft 14, so that the turbine shaft 14 is designed as a hollow shaft, at least in sections. This possible further design form is shown in Fig. 2. In any case, in the described design forms of the turbine-generator device 2 orThe possible designs of the bearing device 12 ensure that a natural pressure difference between the inlet area 7 and the outlet area 8 can be used as the main driving force for flushing the plain bearings 26, 27, 28 with cooling and lubricating fluid taken from the operating medium of the turbine generator device 2.

[0048] In the area of ​​the opening 41, the flow channel 36 can also comprise a throttle element 42 and / or a diffuser element 43 in order to be able to influence the natural pressure difference between the inlet area 7 and the outlet area 8 for flushing the plain bearings 26, 27, 28. This can be advantageous, for example, if an identical turbine generator device 2 is used for different fall cavities and flow rates in order to be able to fine-tune the usable pressure difference for flushing the plain bearings 26, 27, 28 according to the different framework conditions or installation requirements by means of the throttle element 42 and / or the diffuser element 43.

[0049] As shown in Fig. 2, the bearing device 12 can comprise a second hydrodynamic radial plain bearing 28b with a fourth bearing gap 45. The collecting chamber 35 can, as already described, be arranged such that the plain bearings 26, 27, 28, i.e. also the second radial plain bearing 28b, can be sequentially or in series through which the cooling and lubricating fluid can flow, and the cooling and lubricating fluid can be received in the collecting chamber 35 in order to be discharged into the outlet region 8 via the connecting channel 37 and the flow channel 36.

[0050] However, as shown in Fig. 2, an embodiment is also possible in which a second cooling and lubricating fluid inlet 44 is provided, wherein the second cooling and lubricating fluid inlet 44 can in turn receive cooling and lubricating fluid from the operating medium flowing through the turbine generator device 2 during operation. The fourth bearing gap space 45 can thus be supplied with cooling and lubricating fluid by means of the second cooling and lubricating fluid inlet 44, wherein the cooling and lubricating fluid, as before and as shown in Fig. 2, can flow into the collecting space 35 following or downstream of the plain bearings 26, 27, 28 along the flow path 34 of the cooling and lubricating fluid, in order to be able to be discharged into the outlet region 8 via the connecting channel 37 and the flow channel 36.

[0051] The embodiments show possible embodiments, whereby it should be noted at this point that the invention is not limited to the specifically illustrated embodiments thereof, but rather various combinations of the individual embodiments with each other are also possible and this possibility of variation lies within the skill of the person skilled in the art in this technical field due to the teaching of technical action by means of the objective invention.

[0052] The scope of protection is determined by the claims. However, the description and drawings must be used to interpret the claims. Individual features or combinations of features from the various embodiments shown and described may represent independent inventive solutions. The problem underlying these independent inventive solutions can be derived from the description.

[0053] All information on value ranges in this description is to be understood as including any and all sub-ranges thereof, e.g. the information 1 to 10 is to be understood as including all sub-ranges, starting from the lower limit of 1 and the upper limit of 10, ie all sub-ranges begin with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10. For the sake of clarity, it should be pointed out that in order to improve understanding of the structure, some elements have been shown out of scale and / or enlarged and / or reduced.

[0054] Reference symbol list

[0055] Shaft power plant 30 filter and conveying device

[0056] T urbine generator device 31 first bearing gap

[0057] Headwater level 32 second bearing gap space

[0058] Underwater level 33 third bearing gap space

[0059] Inlet basin 34 Flow path of the cooling and

[0060] Ring housing lubricating fluid

[0061] Inlet area 35 collection room

[0062] Outlet area 36 flow channel

[0063] Flow direction 37 Connecting channel

[0064] T urbine runner 38 cover plate

[0065] Turbine rotation axis 39 first cooling and lubricating liquid

[0066] Storage device speed inlet

[0067] Connecting element 40 conveyor element

[0068] Turbine shaft 41 opening

[0069] Ring generator 42 throttle element

[0070] Ring generator stator 43 diffuser element

[0071] Ring generator rotor 44 second cooling and lubricating fluid

[0072] Supporting element speed inlet

[0073] Connection surface 45 fourth bearing gap

[0074] intake manifold

[0075] Counter connection surface

[0076] Flow guide device

[0077] guiding elements

[0078] From support device

[0079] Bottom first axial plain bearing second axial plain bearing

[0080] Radial plain bearings

[0081] forehead end

Claims

Patent claims 1. Turbine-generator unit (2) for generating electricity by converting the energy of a flow between an upstream water level (3) and a downstream water level (4) in a shaft power plant (1) with an intake basin (5), the turbine-generator unit (2) comprising a ring casing (6) with an inlet area (7) and an outlet area (8), a ring generator (15), and a turbine runner (10) with a turbine axis of rotation (11), — wherein the ring housing (6) comprises a pear-shaped bearing device (12) aligned along the turbine axis of rotation (11) in the inlet area (7), — wherein the bearing device (12) is fixedly held in position on the ring housing (6) by means of at least one connecting element (13), — wherein the bearing arrangement (12) comprises a first hydrodynamic axial sliding bearing (26), a second hydrodynamic axial sliding bearing (27) spaced apart from the first axial sliding bearing (26) in the direction of the turbine axis of rotation (11), and a first hydrodynamic radial sliding bearing (28a), wherein a turbine shaft (14) aligned along the turbine axis of rotation (11) is supported by means of the sliding bearings (26, 27, 28), wherein the turbine impeller (10) is rotationally fixedly coupled to the turbine shaft (14) in the outlet region (8), and — wherein in the inlet area (7) a filter and conveying device (30) for the cooling and lubricating fluid to be supplied to the sliding bearings (26, 27, 28) is formed at a first axial end (29) of the bearing device (12), characterized in that — a first bearing gap (31) of the first axial sliding bearing (26), followed by a second bearing gap (32) of the second axial sliding bearing (27) and followed by a third bearing gap (33) of the first radial sliding bearing (28a) are sequentially through which the cooling and lubricating fluid can flow, — wherein the cooling and lubricating fluid can flow into a collection chamber (35) following or downstream of the sliding bearings (26, 27, 28) along the flow path (34) of the cooling and lubricating fluid, and — the turbine shaft (14) has in sections a flow channel (36) that is oriented essentially parallel to the turbine axis of rotation (11), — wherein the flow channel (36) is located in the outlet area (8) of the turbine-generator unit (2) or in the area of ​​the coupling of the turbine shaft (14) with the turbine impeller (10) with the operating medium flowing through the turbine generator unit (2) can be fluidically coupled, and — the turbine shaft (14) has a connecting channel (37) that can be fluidically coupled to the flow channel (36) and the collection chamber (35), so that the bearing device (12) can be permeated by the cooling and lubricating fluid.

2. Turbine generator device (2) according to one of the preceding claims, characterized in that the flow channel (36) is designed along the turbine axis of rotation (11) and rotationally symmetrical to the turbine axis of rotation (11).

3. Turbine generator device (2) according to one of the preceding claims, characterized in that the flow channel (36) in the outlet area (8) comprises a throttle element (42) and / or a diffuser element (43).

4. Turbine generator device (2) according to one of the preceding claims, characterized in that several connecting channels (37) are arranged distributed in the circumferential direction and can each be fluidically coupled to the flow channel (36).

5. Turbine generator device (2) according to claim 1, characterized in that several flow channels (36) are arranged distributed in the circumferential direction and several connecting channels (37) are arranged distributed in the circumferential direction and can each be fluidically coupled to a flow channel (36).

6. Turbine generator device (2) according to one of the preceding claims, characterized in that the bearing device (12) comprises a second hydrodynamic radial sliding bearing (28b) axially spaced from the first radial sliding bearing (28a) in the flow direction (9), wherein the second radial sliding bearing (28b) comprises a fourth bearing gap space (45), wherein the cooling and lubricating fluid can flow into a collection space (35) following or downstream of the sliding bearings (26, 27, 28) along the flow path (34) of the cooling and lubricating fluid.

7. Turbine generator device (2) according to claim 6, characterized in that a second cooling and lubricating fluid inlet (44) is formed in the area of ​​the coupling of the turbine shaft (14) with the turbine impeller (10), wherein the fourth bearing gap space (45) can be fluidically coupled to the second cooling and lubricating fluid inlet (44) and the collecting space (35), so that the fourth bearing gap space (45) can be supplied with cooling and lubricating fluid taken from the operating medium flowing through the turbine generator device (2) by means of the second cooling and lubricating fluid inlet (44).

8. Turbine generator device (2) according to claim 6, characterized in that the fourth bearing gap space (45) of the second radial sliding bearing (28b) is sequentially or in series through which the cooling and lubricating fluid, which can be extracted from the operating medium of the turbine generator device (2) by means of the filter and conveying device (30), can flow following the third bearing gap space (33).

9. Turbine generator device (2) according to one of the preceding claims, characterized in that the filter and conveying device (30) comprises a cover disk (38) rotationally fixed to the turbine shaft (14), wherein a first cooling and lubricating fluid inlet (39) is formed between the cover disk (38) and the bearing device (12), and wherein the cover disk (38) and / or the bearing device (12) has, in the area of ​​the cover disk (38), at least a groove, a channel, a scraper, a rubber lip or a similar guide element in the first cooling and lubricating fluid inlet (39) extending from a first radial distance towards a second radial distance larger relative to the first radial distance.

10. Turbine generator device (2) according to claim 9, characterized in that the bearing gap spaces (31, 32, 33) have flushing grooves, wherein a first gap width of the first cooling and lubricating fluid inlet (39) is smaller than a depth of the flushing grooves.

11. Turbine generator device (2) according to one of the preceding claims, characterized in that the filter and conveying device (30) comprises a conveying element (40) rotationally coupled to the turbine shaft (14), wherein the sliding bearings (26, 27, 28) cooling and lubricating fluid to be supplied to the first bearing gap space (31) is conveyable.

12. Turbine generator device (2) according to one of the preceding claims, characterized in that the turbine generator device (2) comprises a flow guide device (22) with guide elements (23), wherein the flow guide device (22) is arranged in the flow direction (9) between the at least one connecting element (13) and the ring generator (15), wherein the guide elements are each mounted on the bearing device (12) by means of a sliding bearing, wherein the flow guide device (22) is provided by means of a first actuating device for actively controlling the flow to the turbine impeller (10).

13. Turbine generator assembly (2) according to one of the preceding claims, characterized in that the turbine generator assembly (2) can be completely accommodated in the inlet basin (5) of the shaft power plant (1).

14. Turbine generator device (2) according to one of the preceding claims, characterized in that at least three connecting elements (13) are formed, wherein the bearing device (12) is held in a positionally fixed position on the ring housing (6) by means of the at least three connecting elements (13).

15. Turbine generator device (2) according to one of the preceding claims, characterized in that the ring generator (15) of the turbine generator device (2) is designed as a synchronous generator, wherein permanent magnetic poles and / or a brushless excitation machine are / are provided in the ring generator rotor (17) as excitation.

16. Turbine generator device (2) according to claim 14, characterized in that the ring generator (15) is designed to be speed-controlled by means of an electronic control device.

17. Turbine generator device (1) according to one of the preceding claims, characterized in that the turbine impeller (10) has rotatably mounted turbine blades has, wherein the turbine blades are mounted on the ring generator rotor (17) on one side and on the other side on the bearing device (12), wherein the turbine blades are rotatable in the bearing device (12) by means of a second adjusting device.

18. Turbine generator assembly (1) according to one of the preceding claims, characterized in that the ring housing (6) has a support device (24) in the inlet area (7), wherein the turbine generator assembly (1) can be supported on a bottom (25) of the inlet basin (7) by means of the support device (24).

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