Wind turbine power train, wind turbine and method for operating a wind turbine

Abstract

The invention relates to a wind turbine drivetrain, a wind turbine and a method for operating a wind turbine. The invention relates to a wind turbine drivetrain (7) for transmitting torque from a rotor hub (4) to a generator (9), comprising a rotor shaft (11), a low speed lock (21) acting on the rotor hub (4) or the rotor shaft (11), a gearbox (8), a high speed shaft (10), and a high speed lock (20) acting on the high speed shaft (10) or the generator (9), wherein the high speed lock (20) is configured to fix the rotor hub (4) in a plurality of different rotor lock positions, wherein the low speed lock (21) is configured to fix the rotor hub (4) in at most two different rotor positions.

Description

Technical Field

[0001] This invention relates to a wind turbine powertrain for transmitting torque from a rotor to a generator. The invention further relates to a wind turbine including said wind turbine powertrain. The invention further relates to a method for operating a wind turbine. Background Technology

[0002] Wind turbines are increasingly being used to generate electricity. A wind turbine typically consists of a tower and a nacelle mounted on the tower, with a rotor attached to the nacelle. The rotor is connected to a generator via a so-called power drive system. The rotor comprises multiple rotor blades extending from a central rotor hub. The blades are oriented in such a way that wind passing over the blades rotates the rotor and causes the rotor shaft to rotate, thereby driving the generator to produce electricity.

[0003] Wind turbines are constantly evolving due to advancements in technology and energy harvesting. Consequently, the size of newer generations of wind turbines has increased compared to older models. In most modern large wind turbines, a gearbox is positioned between the wind rotor and the generator to reduce the large torque on the rotor side by increasing the speed on the generator side. The powertrain is one of the components that has seen a significant increase in size because the increased rotor torque and power must be transmitted through it.

[0004] During the twenty to thirty-year lifespan of a wind turbine, regular service and maintenance must be performed on many components, such as rotor blades, the blade angle adjustment system (also known as the pitch system) typically mounted inside the rotor hub, and sub-components of the powertrain, such as couplings, bearings, and gearboxes. Due to health and safety requirements, servicing of rotating components can only be performed when the rotating parts are securely locked or fixed relative to the nacelle.

[0005] For this purpose, rotor locks are known at the current level of technology. Due to the increased size of the rotor, rotor locks need to be designed for huge loads, resulting in large and heavy rotor locks that can only be operated with complex procedures and typically hydraulic actuators. Summary of the Invention

[0006] Therefore, the object of this invention is to provide an improved design for the powertrain of a wind turbine that avoids the shortcomings of current manufacturing processes. In particular, the object of this invention is to reduce the size and weight of the wind turbine powertrain and improve its maintainability.

[0007] This is achieved by the wind turbine powertrain according to claim 1, the wind turbine according to claim 9, and the method of operating the wind turbine according to claim 10.

[0008] According to the present invention, a wind turbine power transmission system for transmitting torque from a rotor hub to a generator includes a rotor shaft, a low-speed lock acting on the rotor hub or the rotor shaft, a gearbox, a high-speed shaft, and a high-speed lock acting on the high-speed shaft or the generator. The high-speed lock is configured to secure the rotor hub in a plurality of different rotor lock positions.

[0009] The low-speed lock is configured to fix the rotor hub in at most two different rotor positions, preferably exactly one single rotor lock position.

[0010] The rotor shaft is the input shaft of the gearbox, and the rotor shaft rotates at the same speed as the rotor hub.

[0011] The high-speed shaft is the output shaft of the gearbox, and in a preferred embodiment, the high-speed shaft rotates at the same speed as the generator.

[0012] In one embodiment, fixing the rotating part means establishing a secure connection between the rotating part and the nacelle of the wind turbine, a connection that prevents rotational movement between the rotating part and the nacelle except for elastic deformation of the parts involved in fixing. In a preferred embodiment, fixing means establishing a form-fit or form-locking connection in a lock (which may be a low-speed lock or a high-speed lock), as this is the safest way to secure the rotating part to the nacelle. The terms "fixing the rotating part" and "locking the rotating part" are used synonymously.

[0013] The rotor lock position is the position of the rotor hub as it rotates around its axis of rotation, which is the rotor axis. If, as an example, a rotor blade is named the first rotor blade, this first rotor blade could be in a position between 0 degrees and 360 degrees, depending on the rotor position. In the wind energy industry, a clockwise definition is more common. The 12h position is the vertically upward position of the first rotor blade, and the 6h position is the vertically downward position. Viewed from the windward side of the rotor, the 3h position is the horizontally right-hand position of the first rotor blade, and the 9h position is the horizontally left-hand position.

[0014] During routine service work, securing the rotor in the rotor lock position best suited for performing the planned service work is a significant advantage. For example, if the rotor is secured in a predefined position, it is already easier for service personnel to access the rotor hub. Maintenance work inside the rotor blades is often easiest if the rotor blades are placed in a horizontal position. Service work on pitch system components is also easier when service personnel can stand upright in front of the component to be serviced and if they do not need to work overhead or on the ground.

[0015] Allowing for multiple different rotor lock positions by fixing the high-speed lock offers several advantages: high-speed locks are significantly smaller than low-speed locks, making them easier for service personnel to handle. Handling smaller locking mechanisms is also much safer than handling larger ones, as the risk of hands or fingers getting stuck is significantly reduced when dealing with small parts. Furthermore, adjusting the position of the high-speed shaft for applying the high-speed lock is much easier than adjusting the rotor hub for applying the low-speed lock. All of this advantageously results in a faster and safer procedure for applying the high-speed lock for routine service work compared to applying the low-speed lock.

[0016] According to the invention, the low-speed lock is configured to secure the rotor hub in at most two different rotor positions, preferably exactly one single rotor lock position. Secured in at most two different rotor positions, the rotor lock hardware is minimized in such a way that locking the rotor hub is only possible in one or two rotor positions. This means, for example, that securing the rotor hub with the low-speed lock is only possible when one blade is pointing vertically downwards (the so-called 6h position). If two positions are possible, then, as an example, a blade may be locked in both vertically downwards and vertically upwards positions (the so-called 6h and 12h), or, in alternative embodiments of the invention, for example, in both horizontally to the right and horizontally to the left positions (the so-called 3h and 9h), or, in another alternative embodiment of the invention, for example, only in the horizontally to the right position (the so-called 3h). A significant advantage of limiting the possible rotor lock positions of the low-speed lock is the significant reduction in hardware used for the low-speed lock, resulting in lighter weight and easier manufacturing. Furthermore, service personnel will use high-speed locks for most routine service work, which are easier and faster to apply and thus save time and money. Only in special service tasks where high-speed locks cannot be used on the powertrain (e.g., maintenance work on load transfer components (e.g., couplings) between the high-speed lock and the rotor hub, or maintenance on the high-speed lock itself) will more complex low-speed locks be used to secure the rotor hub. Therefore, the inventors' achievement is recognizing that in the vast majority of service situations, high-speed locks are a faster, safer, and more economical device for locking the rotor hub, and that for the few cases where high-speed locks cannot be applied, simpler and lighter low-speed locks, allowing only one or two different rotor lock positions, are the easiest and most economical solution.

[0017] Another aspect of the invention relates to a wind turbine comprising a tower (2), a nacelle (3), and a wind turbine power transmission system according to the invention.

[0018] Another aspect of the invention relates to a method of operating a wind turbine, the wind turbine including a wind turbine powertrain comprising a plurality of rotor blades, a rotor hub, a gearbox, a high-speed lock, and a low-speed lock. The low-speed lock is configured to secure the rotor hub in at most two different rotor lock positions, preferably exactly one single rotor lock position. The inventive method includes the steps of: operating the wind turbine for generating electrical energy; servicing the wind turbine using the high-speed lock for locking the rotor hub in the plurality of different rotor lock positions for routine servicing work on the rotor hub or rotor blades; and servicing the wind turbine powertrain using the low-speed lock for securing the rotor hub.

[0019] In the context of this disclosure, the term "service" may be interpreted as or may include at least one of the following: performing optical inspection at or within a component of a wind turbine, testing electrical or electronic components, inspecting or adjusting the position of components, cleaning or lubricating components, or replacing worn components.

[0020] The same definitions and advantages discussed in the above claims apply to the inventive method. This method is advantageous because for frequent, routine service work, a high-speed lock that is easy and safe to use will be used, while for service or maintenance work on the powertrain (which includes risks to service personnel when performed with a high-speed lock), a low-speed lock that is more difficult to apply will be used. In one embodiment, this applies to service or maintenance work on load transfer components (e.g., couplings) between the high-speed lock and the rotor hub and inside the gearbox itself, or to maintenance on the high-speed lock itself. Therefore, the use of the inventive method advantageously results in faster and more efficient service work with less risk to service personnel.

[0021] According to a preferred embodiment of the invention, the low-speed lock includes a rotor lock bolt and a lock hole or sleeve configured to receive the rotor lock bolt. Using a rotor lock bolt and a hole is a simple and reliable way to allow a form-fit connection, which advantageously allows for optimal security of the low-speed lock under high loads. When the low-speed lock is applied, the bolt is received by the hole or sleeve, meaning the bolt passes through the hole or sleeve. Using a sleeve to receive the rotor lock bolt is a good solution that allows for easy repair. If the rotor lock bolt damages the sleeve, it can be easily replaced, which is not the case when using a simple hole solution.

[0022] In a preferred embodiment, the axis of the rotor locking bolt and the hole or sleeve is parallel to the rotor axis. Advantageously, this allows for better load-bearing behavior compared to bolts installed with their axis not parallel to the rotor axis.

[0023] Additionally or alternatively, the low-speed lock comprises exactly one or exactly two rotor lock bolts and / or exactly one or exactly two lock holes or sleeves. Using exactly one rotor lock bolt and one hole or sleeve is obviously the simplest and likely advantageous way to design a low-speed lock, as it minimizes the number of components and required hardware. Using exactly two rotor lock bolts is an advantage for load distribution, as the high load from the low-speed lock can be distributed in two spots, thus advantageously, for example, symmetrically distributed on both sides of the nacelle. Furthermore, the use of two bolts reduces the required bolt size and makes the parts easier to handle. Since the size of the rotor lock bolt is critical, using two smaller rotor lock bolts instead of one larger rotor lock bolt can even be a cost advantage. Using more than two rotor lock bolts has proven difficult in the past because it is necessary to ensure that both rotor lock bolts bear the same load. Therefore, they cannot be considered redundant, as if the load were so high that if one bolt cracked, the second bolt would immediately follow suit. Using exactly two lock holes or sleeves provides the same advantages as with two bolts, except that the load will be distributed in two spots on the rotating part. In a preferred embodiment, if the low-speed lock comprises two bolts, two rotor lock bolts are always used, as this is the only way to allow for the full load-bearing capacity and efficient design of the applied low-speed lock, since their size can be advantageously reduced if the bolts are always used simultaneously. Of particular interest are two combinations (one rotor lock bolt and two holes or two sleeves, and two rotor lock bolts and one hole or one sleeve) that advantageously allow for two rotor lock positions. The latter combination will allow for some redundancy, for example, if one of the bolts gets stuck and cannot be applied by, for example, a hydraulic actuator, but the disadvantage is that the cost is significantly higher with two rotor lock bolts. In a first advantageous embodiment of two rotor lock bolts and two holes or two sleeves, the bolts and holes or sleeves are arranged in a straight line through the rotor axis and at the same radial distance along the axis of rotation. This symmetrical 180-degree arrangement allows full utilization of the reduced rotor lock bolt size, since two bolts will be applied simultaneously, and allows for two rotor lock positions, as the rotor hub can rotate approximately 180 degrees to obtain a second rotor lock position, where the low-speed lock can again be applied using two rotor lock bolts.

[0024] In a second advantageous embodiment, with two rotor locking bolts and two holes or two sleeves, the bolts and holes or sleeves are arranged on a straight line that does not intersect the rotor axis. In this embodiment, only a single rotor locking position is possible, where two bolts are applied as needed to achieve the load-bearing capacity of the low-speed lock. This embodiment advantageously allows for a better load path from the high-load rotor locking bolts to the nacelle support structure.

[0025] According to a preferred embodiment of the invention, the rotor lock bolts are attached to the base frame or the shaft housing. Attaching the rotor lock bolts directly or indirectly to the base frame or the shaft housing advantageously allows for a direct load path to support the high loads generated from the low-speed lock. In some embodiments, the base frame is the main frame of the nacelle, and the shaft housing is a bearing housing for the rotor shaft. Attaching the rotor lock bolts to the main frame or bearing housing advantageously results in a very secure attachment of the rotor lock bolts.

[0026] According to a preferred embodiment of the invention, the low-speed lock, or its components, is detachable and is only installed on the wind turbine powertrain when required for necessary service or maintenance work. This advantageously reduces the weight and cost of the powertrain because these detachable components of the low-speed lock must be supplied in limited quantities for the wind turbine fleet, as it is only used as a service tool when needed.

[0027] According to an alternative preferred embodiment of the invention, the low-speed lock is permanently mounted on the powertrain. Permanent mounting means that the low-speed lock, or parts thereof, is not removed from the wind turbine powertrain when not needed for servicing or maintenance work. This advantageously allows for faster and safer application of the low-speed lock, as no preparatory work is required.

[0028] According to a preferred embodiment of the invention, the locking hole or sleeve is arranged in the casting of the rotor hub. In this embodiment, the hole or sleeve is directly implemented in the cast body of the rotor hub or in the flange of the rotor hub. This advantageously allows for the most direct load path for securing the rotor hub and minimizes the required hardware, thus reducing the weight of the powertrain.

[0029] According to a preferred embodiment of the invention, the locking hole or sleeve is arranged in a protrusion, which is part of the rotor shaft flange. By integrating the hole or sleeve into the protrusion, which is a single piece of hardware with the rotor shaft flange, a very simple and lightweight design is achieved. Advantageously, a locking plate mounted on the rotor shaft or rotor hub is not required, saving weight in the powertrain. Additionally, no additional interfaces or connections are needed, improving the reliability of low-speed locking. In a preferred embodiment, the protrusion of the rotor shaft flange is a limited area of ​​the rotor shaft flange in which the outer diameter of the flange increases. Since only one or two protrusions exist on the rotor shaft flange, the transport dimensions are significantly reduced compared to conventional locking plates with a larger number of locking holes attached to the rotor shaft. In a preferred embodiment, the protrusion and the rotor shaft flange are integrally cast, welded, or forged. Casting the protrusion and rotor shaft flange as a single part allows for a very economical production process, especially for mass production. Welding the protrusion to the rotor shaft flange allows for easy implementation of the solution even on existing rotor shafts. Forging the protrusion and rotor shaft flange into a single piece advantageously allows for a very robust and reliable low-speed lock.

[0030] According to a preferred embodiment of the invention, the high-speed lock is configured to lock the rotor hub in at least three different positions. The at least three different positions include a first locking position in which the first rotor blades point vertically downwards, a second locking position in which the first rotor blades point horizontally, and a third locking position in which the second rotor blades point horizontally. As in conventional wind turbine gearboxes, where the gear ratio is greater than ten, and one revolution on the high-speed shaft is less than one-tenth the length of one revolution on the rotor hub, a simple high-speed lock with one locking position on the high-speed shaft allows for at least ten rotor locking positions on the rotor hub.

[0031] During routine service work, different rotor positions allow for easier maintenance. Locking the rotor hub with a high-speed lock is the easiest and fastest way to lock the hub in the preferred position. In various situations, the rotor lock position, 6h position, or also known as the rabbit-ear position, where the first rotor blade points vertically downwards, is advantageous. First, it allows for easy external inspection using a work platform suspended from cables or ropes attached to the rotor hub, tower, or nacelle. Furthermore, this is the optimal position when a helicopter approaches the nacelle (e.g., to hoist replacement parts or service personnel into the nacelle), as the two upward-pointing rotor blades in the rabbit-ear or Y position minimize interference to the approaching helicopter. The position where the first rotor blade points horizontally is advantageous for inspecting the first rotor blade from the inside, as service personnel can walk effortlessly inside the blade. The position where the second rotor blade points horizontally is advantageous for inspecting the second rotor blade from the inside.

[0032] According to a preferred embodiment of the invention, a high-speed lock is configured to securely lock the rotor hub up to a first design wind speed, and a low-speed lock is configured to securely lock the rotor hub up to a second design wind speed, wherein the first and second design wind speeds are different from each other. Typically, the rotor lock is only designed to securely hold the rotor up to a certain wind speed because at very high wind speeds, releasing the rotor to idle is often preferred, as this results in lower loads on the rotor blades and the entire wind turbine. On the other hand, an advantage is that maintenance work can also be performed at high wind speeds to avoid service personnel having to wait until favorable weather conditions occur. Because the high-speed lock acts on the rotor hub with a gearbox multiplier effect, the torque that must be supported by the high-speed lock is typically 10 to more than 100 times lower than the torque that needs to be supported by the low-speed lock. For this reason, the low-speed lock, designed for a lower design wind speed than the high-speed lock, saves significant amounts of material, weight, and cost. For that reason, in a preferred embodiment of the invention, the design wind speed for the low-speed lock is lower than the design wind speed for the high-speed lock.

[0033] On the other hand, routine service work (e.g., rotor hub and rotor blade inspection) is much easier to plan and schedule than unplanned maintenance work (e.g., gearbox replacement after gearbox failure). Therefore, in an alternative preferred embodiment, the design wind speed for the high-speed lock is lower than that for the low-speed lock. This advantageously allows the rotor hub to be securely locked using the low-speed lock at high wind speeds following an unpredictable gearbox failure.

[0034] According to a preferred embodiment of the method for operating a wind turbine, the steps of servicing a wind turbine for routine service work include: moving service personnel inside the rotor hub, and performing service work inside the rotor hub or inside one of the rotor blades, as discussed above. Applying high-speed locks for these routine service operations is advantageous because they are easier, safer, and faster to apply.

[0035] According to a preferred embodiment of the invention, the steps of servicing a wind turbine for routine servicing work include at least two of the following steps: rotating the rotor hub to a position where the first rotor blade is positioned vertically downward or horizontally; performing servicing work inside or outside the first rotor blade; rotating the rotor hub to a position where the second rotor blade is positioned vertically downward or horizontally; or performing servicing work inside or outside the second rotor blade. As mentioned above, for a given servicing operation, it is preferable to position the rotor hub in a predetermined position (e.g., where the rotor blade to be serviced is placed in a horizontal position), as this is particularly advantageous for servicing work performed from the inside or when the rotor blade to be serviced is placed in a vertically downward pointing position (6h position), as this allows for the easiest access from the outside using a work platform or even a rope climber. Locking the rotor hub in these routine servicing rotor lock positions using a high-speed lock instead of a low-speed lock is particularly easy and safe. Preferably, at least three of the steps mentioned above are performed in the method, and most preferably all four steps, thereby advantageously allowing service operations to be performed on two, preferably all, rotor blades of the wind turbine in a simple and efficient manner.

[0036] According to a preferred embodiment of the method for operating a wind turbine, the steps of servicing the wind turbine powertrain include at least one of the following steps: performing servicing work on the connection between the rotor shaft and the gearbox, performing servicing work on a high-speed lock, performing servicing work inside the gearbox, removing gearbox components, or removing the entire gearbox. Servicing a powertrain that includes one of the aforementioned steps cannot be performed using a high-speed lock, or can only be performed using a high-speed lock under highly risky conditions, because even with a high-speed lock applied, it cannot be ruled out that the components to be serviced are under considerable load, thus also endangering service personnel working on these components. However, the inventors have recognized that for these servicing activities, the rotor position in which the rotor hub is locked is less important. Therefore, a significant advantage of the present invention is that these powertrain servicing operations are performed using a simpler low-speed lock, as is known in current technology, to lock the rotor hub, because this simpler low-speed lock advantageously allows the same level of safety to be achieved without the need for complex low-speed locks that allow for more than one or two rotor positions.

[0037] According to a preferred embodiment of a method for operating a wind turbine, particularly an offshore wind turbine, further particularly a floating offshore wind turbine, and / or for feeding electrical and / or chemical energy into an electric and / or chemical power grid, the method comprises the steps of: generating electrical power and / or electrical energy from the wind turbine, and particularly at least partially generating chemical energy from the electrical energy, further particularly converting the electrical energy into hydrogen gas through electrolysis to generate chemical energy in the form of a gas or liquid, particularly in the form of hydrogen gas; transferring at least partially the electrical power, electrical energy, and / or chemical energy to an energy receiving arrangement, particularly wherein the receiving arrangement is not located in international waters, but on land and / or within a 12-mile zone of a corresponding sovereign state, which has jurisdiction over the 12-mile zone; and supplying at least partially the electrical power, electrical energy, and / or chemical energy to an electric and / or chemical utility power grid, particularly to an onshore electric and / or chemical utility power grid and / or chemical / electric storage device.

[0038] According to a preferred embodiment of a method for operating a wind turbine, particularly an offshore wind turbine, further particularly a floating offshore wind turbine, and / or for feeding electrical and / or chemical energy into an electric and / or chemical power grid, the method includes the steps of: operating a power transmission system; generating electrical power and / or electrical energy from the wind turbine, and particularly at least partially generating chemical energy from the electrical energy, further particularly generating chemical energy by electrolysis of the electrical energy into hydrogen, the chemical energy being in the form of a gas or liquid, particularly in the form of hydrogen; transferring at least partially the electrical power, electrical energy, and / or chemical energy to an energy receiving arrangement, particularly wherein the receiving arrangement is not located in international waters, but on land and / or within a 12-mile zone of a corresponding sovereign state, the corresponding state having jurisdiction over the 12-mile zone; and supplying at least partially the electrical power, electrical energy, and / or chemical energy to an electric and / or chemical utility grid, particularly to an onshore electric and / or chemical utility grid and / or chemical / electric storage device.

[0039] Additionally and / or alternatively, other aspects are disclosed, and / or particularly as an embodiment of one of the foregoing aspects and / or embodiments, namely, a method for operating a wind turbine, particularly an offshore wind turbine, further particularly a floating offshore wind turbine, and / or for feeding electrical and / or chemical energy into an electric and / or chemical power grid, the method comprising the following steps: Performing steps of one embodiment or a combination of embodiments of the methods disclosed above, and / or operating embodiments of the apparatus disclosed above; The wind turbine generates electrical power and / or electrical energy, and in particular at least partially generates chemical energy from electrical energy, and further particularly generates chemical energy by electrolysis of electrical energy into hydrogen gas, which is in the form of gas or liquid, especially in the form of hydrogen gas. At least partially, electrical power, electrical energy, and / or chemical energy are transferred to an energy receiving arrangement, particularly wherein the receiving arrangement is not located in international waters, but on land and / or within a 12-mile zone of a sovereign state having jurisdiction over that 12-mile zone; and At least in part, electrical power, electrical energy and / or chemical energy are supplied to electrical and / or chemical utility grids, particularly to onshore electrical and / or chemical utility grids and / or chemical / electric storage devices.

[0040] The term "chemical energy" includes devices for storing energy in chemical substances, such as hydrogen. A chemical energy network can be, for example, a hydrogen supply network and / or a storage device.

[0041] It must be noted that embodiments of the invention have been described with reference to various subject matter. In particular, some embodiments have been described with reference to device-type subject matter (such as a wind turbine powertrain for transmitting torque from a rotor hub to a generator), while other embodiments have been described with reference to method-type subject matter (such as a method of operating a wind turbine). However, those skilled in the art will infer from the foregoing and following description that, unless otherwise notified, any combination of features related to different subject matter (particularly between features of device-type claims and features of method-type claims) is also considered to be disclosed with this application, except for any combination of features belonging to one type of subject matter. Attached Figure Description

[0042] To facilitate understanding of the features of the invention and as part of this specification, accompanying drawings have been provided, in which the following are indicated by illustrative but non-limiting characters: Figure 1 A wind turbine is shown, having a wind turbine power transmission system according to the invention for transmitting torque from a wind turbine rotor to a generator.

[0043] Figure 2 The wind turbine power transmission system according to the present invention is schematically shown.

[0044] Figure 3 An embodiment of a rotor shaft as known in the prior art is shown.

[0045] Figure 4 An embodiment of the rotor shaft according to the present invention is shown.

[0046] Figure 5 A front view of an embodiment of a rotor shaft with a bearing platform according to the present invention is shown. Detailed Implementation

[0047] Figure 1 A wind turbine 1 with a tower 2 and a nacelle 3 is shown, the nacelle including a wind turbine powertrain 7. Rotarily attached to the nacelle 3 is a wind turbine rotor with a rotor hub 4 having multiple rotor blades 5. Torque generated by the wind turbine rotor is transmitted to a gearbox 8 via a rotor shaft 11. The rotor shaft 11 rotates about a rotor axis 15. The output torque of the gearbox 8 is transmitted to a generator 9 via a high-speed shaft 10 to generate electricity. The powertrain 7 is supported by a base frame 16, which is rotatably attached to the tower 2.

[0048] Figure 2A wind turbine powertrain 7 is shown, comprising a rotor shaft 11, a low-speed lock 21, a gearbox 8, a high-speed shaft 10, and a high-speed lock 20. In the illustrated embodiment, the low-speed lock 21 acts on a lock plate 22 attached to the rotor shaft 11 via rotor lock bolts 25. In other embodiments, the rotor lock bolts 25 act directly on the rotor hub 4 or on the lock plate 22 attached to the rotor hub 4. The low-speed lock 21 is configured to secure the rotor hub 4 in exactly one or exactly two rotor lock positions, thus securing it in at most two different rotor lock positions, meaning it is in two different angular positions of the rotor hub 4 about the rotor axis 15. In the illustrated embodiment, the low-speed lock 21 includes exactly one rotor lock bolt 25; in other embodiments, it includes exactly two rotor lock bolts 25. The lock plate 22 includes exactly one lock hole 24 (not visible), or in other embodiments, it includes exactly two lock holes 24 for receiving the rotor lock bolts 25. The high-speed lock 20 includes rotor lock bolts 25 acting on a lock plate 22, which, in the illustrated embodiment, is attached to the high-speed shaft 10. In other embodiments, the high-speed lock 20 may act directly on the generator 9. The high-speed lock is configured to lock the rotor hub 4 in multiple different rotor lock positions. According to the invention, it is envisioned to operate the wind turbine 1 using the wind turbine powertrain 7 for generating electrical energy. For routine service work on the wind turbine rotor including the rotor hub 4 and rotor blades 5, the high-speed rotor lock 20 is applied to secure the rotor hub 4 in the most suitable rotor lock position. For a particular service work, this might be as follows: Figure 2 The rotor lock position is shown, with the first rotor blade 5 pointing vertically downwards. If servicing work on the first rotor blade 5 is completed, the high-speed lock 20 will be released and the rotor hub 4 will be repositioned so that the second rotor blade 5 points vertically downwards. The high-speed lock 20 will be applied again, and servicing work can be performed on the second rotor blade 5. On a wind turbine 1 with three rotor blades 5, the same process will be performed on the third rotor blade 5. Afterwards, the high-speed lock 20 will be released, and the wind turbine 1 will be operated again to generate electricity.

[0049] For other service work, it would be advantageous to use the high-speed lock 20 to secure the rotor hub 4 with the rotor blades 5 pointing horizontally, using the same method as just described. For servicing the wind turbine powertrain 7, a low-speed lock 21 will be applied. This more complex procedure is required, for example, for performing service work on the connection between the rotor shaft 11 and the gearbox 8, on the high-speed lock 20, within the gearbox 8, or for removing parts of the gearbox 8 or the entire gearbox 8. If it can be easily done in… Figure 2As seen, all these service and maintenance tasks are performed on components located in the load path between the rotor hub 4 and the high-speed lock 20. Therefore, work on these components would put service personnel at risk, because if the rotor hub 4 is secured with the high-speed lock 20, the load from the rotor blades 5 would be transmitted through the components, thus posing a safety hazard to service personnel. Since the safety of service personnel is ensured regardless of the rotor position when the rotor hub 4 is secured with the low-speed lock 21, the present invention advantageously improves upon the wind turbine powertrain 7 and the method for operating the wind turbine 1 as known in current technology.

[0050] Figure 3 A rotor shaft 11 as known in the prior art is shown. Attached to the rotor shaft 11 is a rotor lock plate 22 comprising three parts. The rotor lock plate 22 includes a total of six locking holes 24, thereby allowing the rotor hub 4 to be locked in multiple different rotor lock positions. The large rotor lock plate 22 adds a significant weight to the wind turbine powertrain 7 and requires numerous bolts to be secured to the rotor shaft 11 in order to transfer heavy loads from the low-speed lock 21 to the rotor shaft 11.

[0051] Figure 4 A rotor shaft 11 according to the invention is shown. Two protrusions 23 are cast directly onto the rotor shaft flange 12. In the illustrated embodiment, the rotor shaft 11, rotor shaft flange 12, and two protrusions 23 are cast or forged as a single piece. In other embodiments, the protrusions 23 may be welded to the rotor shaft flange 12. In some embodiments, the rotor shaft 11 and rotor shaft flange 12 may be two parts joined together. When compared... Figure 3 and Figure 4 At that time, it was obvious that, with Figure 3 Compared with existing technologies, Figure 4 Its inventive design avoids significant weight and complexity. Furthermore, Figure 4 The transport size ratio of the inventive embodiment shown Figure 3 The existing technology shown is much easier to handle.

[0052] Figure 5The previous view shows a rotor shaft 11 including a shaft base 17. A rotor shaft flange 12, including two rows of bolt holes for connection to a rotor hub 4 (not shown), has protrusions 23 with locking holes 24 on the left and right sides. In the illustrated embodiment, the two protrusions 23 are cast directly with the rotor shaft flange 12. In other embodiments, the protrusions 23 may be cast directly with the flange of the rotor hub 4, or the locking holes 24 or sleeves may be directly integrated into the rotor hub 4. Two rotor locking bolts 25 are visible inside the two locking holes 24. Therefore, the illustrated embodiment has exactly two locking holes 24 and exactly two rotor locking bolts 25. The axes of the rotor locking bolts 25 and the axes of the locking holes 24 are parallel to the rotor axis 25. As in the illustrated embodiment, the straight line through the locking holes 24 does not intersect the rotor axis 15, and the locking holes 24 are not arranged in a 180-degree position on the rotor shaft flange 12. Because two rotor bolts 25 are required to securely fasten the rotor hub 4, the illustrated embodiment allows only exactly one rotor locking position. In other embodiments, the two locking holes 24 can be arranged at a 180-degree angle on the rotor shaft flange 12, thus allowing exactly two rotor lock positions. Compared to a symmetrical 180-degree arrangement, the locking holes 24 are arranged downwardly offset, which advantageously results in a better load path to the base frame 16 (not shown), to which the shaft mount 17 will be attached. In the illustrated embodiment, both rotor lock bolts 25 are attached to the shaft mount 17. In other embodiments, the rotor lock bolts 25 will be arranged directly on the base frame 16. The protrusions 24 and rotor lock bolts 25 are not designed for easy removal, therefore they are permanently mounted on the wind turbine powertrain 7 to allow for easy and quick application of the low-speed lock 21 when needed.

[0053] While specific embodiments have been disclosed herein, various changes and modifications can be made without departing from the scope of the invention. These embodiments are to be considered illustrative and non-limiting in all respects, and all changes are intended to be covered therein within the meaning and scope of the appended claims.

[0054] List of reference numerals 1. Wind turbine 2 towers 3 Cabin 4 Rotor hub 5 Rotor blades 7. Wind turbine power transmission system 8 Gearbox 9. Generator 10 High-speed shaft 11 Rotor shaft 12 Rotor shaft flange 15. Rotor shaft 16. Base Frame 17-axis platform 20 High-speed locks 21 Low-speed lock 22 Locking Plate 23. Protrusion 24 keyholes 25 Rotor locking bolts

Claims

1. A wind turbine power transmission system (7) for transmitting torque from a rotor hub (4) to a generator (9), the wind turbine power transmission system comprising: Rotor shaft (11), low-speed lock (21) acting on the rotor hub (4) or the rotor shaft (11), gearbox (8), high-speed shaft (10), and high-speed lock (20) acting on the high-speed shaft (10) or the generator (9). The high-speed lock (20) is configured to fix the rotor hub (4) in multiple different rotor lock positions. The low-speed lock (21) is configured to fix the rotor hub (4) in at most two different rotor positions, preferably in a single rotor lock position.

2. The wind turbine power transmission system (7) according to the preceding claim. in, The low-speed lock (21) includes a rotor lock bolt (25) and a lock hole (24) or sleeve configured to receive the rotor lock bolt (25), and / or The low-speed lock (21) includes exactly one or exactly two rotor lock bolts (25), and / or The low-speed lock (21) includes exactly one or exactly two lock holes (24) or sleeves.

3. The wind turbine power transmission system (7) according to the preceding claim, wherein, The rotor locking bolt (25) is attached to the base frame (16) or the shaft stand (15).

4. The wind turbine power transmission system (7) according to claims 2 to 3, wherein, The lock hole (24) or the sleeve is arranged in the casting of the rotor hub (4).

5. The wind turbine power transmission system (7) according to claims 2 to 3, wherein, The locking hole (24) or the sleeve is arranged in the protrusion (23), wherein the protrusion (23) is a component of the rotor shaft flange (12), wherein, in particular, the protrusion (23) and the rotor shaft flange (12) are integrally cast, welded or forged.

6. The wind turbine power transmission system (7) according to any one of the preceding claims, wherein, The low-speed lock (21) is permanently installed on the power transmission system (7).

7. The wind turbine power transmission system (7) according to any one of the preceding claims, wherein, The high-speed lock (20) is configured to lock the rotor hub (4) in at least three different positions, wherein the at least three different positions include a first locking position in which the first rotor blade (5) points in a vertically downward direction, a second locking position in which the first rotor blade (5) points in a horizontal direction, and a third locking position in which the second rotor blade (5) points in a horizontal direction.

8. The wind turbine power transmission system (7) according to any one of the preceding claims, wherein, The high-speed lock (20) is configured to securely lock the rotor hub (4) up to a first design wind speed and the low-speed lock (21) is configured to securely lock the rotor hub (4) up to a second design wind speed, wherein the first design wind speed and the second design wind speed are different from each other.

9. A wind turbine (1) comprising a tower (2), a nacelle (3) and a power transmission system (7) according to any one of the preceding claims.

10. A method of operating a wind turbine (1), particularly a wind turbine according to the preceding claim, the wind turbine (1) comprising a wind turbine power transmission system (7), the wind turbine power transmission system comprising a plurality of rotor blades (5), a rotor hub (4), a gearbox (8), a high-speed lock (20) and a low-speed lock (21), wherein, The low-speed lock (21) is configured to fix the rotor hub (4) in at most two different rotor lock positions, preferably exactly one single rotor lock position, the method comprising the following steps: The wind turbine (1) is operated to generate electrical energy; The wind turbine (1) is serviced using high-speed locks (20) for locking the rotor hub (4) in multiple different rotor lock positions to perform routine servicing work on the rotor hub (4) or on the rotor blades (5), and The low-speed lock (21) is used to serve the wind turbine powertrain (7).

11. The method of operating a wind turbine (1) according to the preceding claim, wherein, The steps for servicing the wind turbine (1) for routine service work include the following: The service personnel were transferred to the interior of the rotor hub (4), and The service work is performed inside the rotor hub (4) or inside one of the rotor blades (5).

12. The method of operating a wind turbine (1) according to claim 10 or 11, wherein, The steps of servicing the wind turbine (1) for routine service work include at least two of the following steps: Rotate the rotor hub (4) to a position where the first rotor blade (5) is positioned vertically downward or horizontally. Service work is performed inside the first rotor blade or on the outside of the first rotor blade (5). Rotate the rotor hub (4) to position the second rotor blade (5) in a vertically downward or horizontal position, or The service work is performed inside the second rotor blade or on the outside of the second rotor blade (5).

13. The method of operating a wind turbine (1) according to claims 10 to 12, wherein, The steps of servicing the wind turbine powertrain (7) include at least one of the following steps: Perform service work on the connection between the rotor shaft (11) and the gearbox (8). Perform service work on the high-speed lock (20), Service work is performed inside the gearbox (8). Remove the components of the gearbox (8), or Remove the entire gearbox (8).

14. A method for operating a wind turbine (1) according to any one of claims 1 to 9, particularly an offshore wind turbine, further particularly a floating offshore wind turbine, and / or for feeding electrical and / or chemical energy into an electric and / or chemical power grid, the method comprising the steps of: The wind turbine (1) generates electrical power and / or electrical energy, and in particular at least partially generates chemical energy from the electrical energy, and further particularly generates chemical energy by converting the electrical energy into hydrogen through electrolysis, the chemical energy being in the form of a gas or liquid, particularly in the form of hydrogen. At least partially, the electrical power, the electrical energy, and / or the chemical energy are transferred to an energy receiving arrangement, particularly wherein the receiving arrangement is not located in international waters, but on land and / or within a 12-mile zone of a sovereign state over which the sovereign state has jurisdiction; and The electrical power, electrical energy, and / or chemical energy are supplied at least in part to the electrical and / or chemical utility grid, particularly to the onshore electrical and / or chemical utility grid and / or chemical / electric storage device.

15. A method for operating a wind turbine (1), particularly an offshore wind turbine, further particularly a floating offshore wind turbine, and / or for feeding electrical and / or chemical energy into an electric and / or chemical power grid, said method comprising the steps of: The method according to any one of claims 10 to 13 is used to operate the wind turbine. The wind turbine (1) generates electrical power and / or electrical energy, and in particular at least partially generates chemical energy from the electrical energy, and further particularly generates chemical energy by converting the electrical energy into hydrogen through electrolysis, the chemical energy being in the form of a gas or liquid, particularly in the form of hydrogen. At least partially, the electrical power, the electrical energy, and / or the chemical energy are transferred to an energy receiving arrangement, particularly wherein the receiving arrangement is not located in international waters, but on land and / or within a 12-mile zone of a sovereign state over which the sovereign state has jurisdiction; and The electrical power, electrical energy, and / or chemical energy are supplied at least in part to the electrical and / or chemical utility grid, particularly to the onshore electrical and / or chemical utility grid and / or chemical / electric storage device.

Images