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EP-4741607-A2 - METHOD AND BLADE INSTALLATION DEVICE FOR INSTALLING A BLADE OF AN OFFSHORE WIND TURBINE

EP4741607A2EP 4741607 A2EP4741607 A2EP 4741607A2EP-4741607-A2

Abstract

Installing a blade on a horizontal axis rotational hub of an offshore wind turbine. Use is made of a blade installation device that is temporarily installed on the offshore wind turbine. A mounting part is mounted on the foundation of the offshore wind turbine and/or on a lower portion of the wind turbine mast. A crane mast is erected vertically and is supported by the mounting part. The crane mast is configured to be composed of crane mast segments that are stackable one-by-one onto one another. A crane mast lifting unit is operated to repeatedly perform lifting actions in the process of erecting the crane mast. The blade installation device further comprises a hoist system with a crane boom that is mounted to a top end of the crane mast, a winch, and a winch driven cable.

Inventors

  • WIJNING, DIEDERICK BERNARDUS

Assignees

  • Itrec B.V.

Dates

Publication Date
20260513
Application Date
20230615

Claims (15)

  1. Blade installation device (20) for installing a blade (10) on a horizontal axis rotational hub of an offshore wind turbine, the offshore wind turbine (1) comprising a wind turbine mast (2) that is supported by a foundation, e.g. a floating foundation (3), of the offshore wind turbine and comprising a nacelle (4) with a horizontal axis rotational hub (5) provided on the top end of the wind turbine mast, which blade installation device (20) is adapted to be temporarily installed on the offshore wind turbine (1) for the installation of the one or more blades (10), wherein the blade installation device (20) is configured to be transported, e.g. on a crane vessel (200), to the offshore wind turbine, wherein the blade installation device comprises a mounting part (30) that is configured to be mounted on the foundation (3) of the offshore wind turbine and/or on a lower portion of the wind turbine mast (2,2a), wherein the blade installation device comprises a crane mast (40) that is configured to be erected vertically in an operational position wherein the crane mast is supported by the mounting part (30) and extends parallel and adjacent to the wind turbine mast, e.g. the crane mast having a track (60), wherein the blade installation device comprises a support bracket (71,72) that is configured to be engaged with the wind turbine mast (2) and laterally supports the erected crane mast (40), wherein the blade installation device further comprises a hoist system (80) with a crane boom (81) that is mounted to a top end of the crane mast (40), a winch (82), and a winch driven cable (83), and wherein the blade installation device is configured for lifting of the blade (10) to a blade installation position (bip) by operating the winch of the hoist system, wherein the crane mast is configured to be composed of crane mast segments (40a - f) that are stackable one-by-one onto one another, and wherein the blade installation device further comprises a crane mast lifting unit (45) configured to be operated to repeatedly perform lifting actions in the process of erecting the crane mast (40).
  2. Device according to claim 1, wherein the crane mast segments (40a - f) are embodied as latticed segments having main chords at the corners, e.g. with a square horizontal cross-section, e.g. wherein the horizontal cross-section of the mast segments exceeds 4.00m x 4.00m.
  3. Device according to claim 1 or claim 2, wherein the crane mast segments (40a - f) each have a length/height of at least 15 meters, e.g. of between 15 and 30 meters, e.g. of about 25 meters.
  4. Device according to any one or more of the preceding claims, wherein the crane mast has a length of at least 100 meters and is composed of no more than ten crane mast segments, e.g. of six crane mast segments.
  5. Device according to any one or more of the preceding claims, wherein all crane mast segments (40a - f) are placed on the blade installation device ahead of the device (20) together with the crane mast segments being transferred from a vessel, e.g. the crane vessel (200), to the offshore wind turbine.
  6. Device according to any one or more of the preceding claims, wherein the crane mast segments (40a - f) are arranged in vertical orientation and side by side on the blade installation device, e.g. in an array extending over an arc.
  7. Device according to any one or more of the preceding claims, wherein the blade installation device comprises a magazine in which the crane mast segments (40a - f) are stored, and which magazine is configured to move the crane segments in succession from their respective storage position to the position where the crane mast segment is assembled with the crane mast.
  8. Device according to any one or more of the preceding claims, wherein the crane mast is configured so that stacking of crane mast segments (40a - f) onto one another is done from below, wherein the lifting unit (45) is configured to remain stationary and connected to the mounting part (30) in a crane mast assembly phase, with the crane mast (40) being lengthened in upward direction from the lifting unit.
  9. Device according to any one or more of the preceding claims, wherein the hoist system comprises a hoisting unit comprising the crane boom and the winch mounted to a hoisting unit base, e.g. having a slew bearing, which hoisting unit is mounted on a first crane mast segment and is moved up along the wind turbine mast in the process of assembly of the crane mast.
  10. Device according to any one or more of the preceding claims, wherein the crane boom (81) is a pivotal boom having its inner end pivotal about a horizontal pivot axis with a corresponding pivoting actuator assembly, e.g. with hydraulic actuators, for example wherein the crane boom is a single segment rigid boom (81) having its inner end pivoted to a base that is connected to the crane mast, e.g. a slewable base, and having its outer end provided with one or more departure sheaves from which one or more winch driven cables depend.
  11. Device according to any one or more of the preceding claims, wherein the device comprises a spreader structure (90) configured to extend along the length of the blade, e.g. above the blade, from an inner end thereof that is at or near the root of the blade to an outer end that is beyond the centre of gravity of the blade, wherein, preferably, the spreader structure (90) is configured to hold the blade at two locations that are inwardly and outwardly remote from the actual COG of the blade, e.g. wherein the spreader is equipped with a guide device at its inner end that is configured to engage on the crane mast, e.g. on a track fitted on the crane mast, so as to guide the inner end relative to the crane mast.
  12. Method for installing a blade (10) on a horizontal axis rotational hub (5) of an offshore wind turbine, the offshore wind turbine (1) comprising a wind turbine mast (2) that is supported by a foundation, e.g. a floating foundation (3), of the offshore wind turbine and comprising a nacelle (4) with a horizontal axis rotational hub (5) provided on the top end of the wind turbine mast, wherein use is made of the blade installation device (20) according to any one or more of the claims 1 - 11, wherein the blade installation device (20) is transported, e.g. on a crane vessel (200), to the offshore wind turbine, wherein a crane (220,240) of a vessel is used for the temporary installation of the blade installation device (20) on the offshore wind turbine, and wherein the crane mast is composed of crane mast segments (40a - f) that are stacked one-by-one onto one another, and wherein the crane mast lifting unit (45) is operated to repeatedly perform lifting actions in the process of erecting the crane mast (40), e.g. wherein the stacking of crane mast segments (40a - f) onto one another is done from below, e.g. wherein the crane mast segments (40a - f) each have a length/height of at least 15 meters, e.g. of between 15 and 30 meters, e.g. of about 25 meters.
  13. Method according to claim 12, wherein all crane mast segments (40a - f) are placed on the blade installation device (20) ahead of the device together with the crane mast segments (40a - f) being transferred from a vessel, e.g. the crane vessel (200), to the offshore wind turbine.
  14. Method according to claim 12 or 13, wherein the crane mast segments (40a - f) are arranged in vertical orientation and side by side on the blade installation device, e.g. in an array extending over an arc, e.g. wherein the blade installation device comprises a magazine in which the crane mast segments are stored, and which magazine is configured to move the crane segments in succession from their respective storage position to the position where the crane mast segment is assembled with the crane mast.
  15. Method according to any one or more of claims 12 - 14, wherein a separate manipulator device for the root end of the blade is installed first at the top end of the wind turbine mast, e.g. fitted to the top end of the mast or to the nacelle, or wherein use is made of the blade installation device according to claim 11 and the manipulator device for the root end of the blade is integrated into the inner end of the spreader.

Description

The present invention relates to a method and a blade installation device for installing a blade of an offshore wind turbine having a nacelle with a horizontal axis rotational hub that is arranged on top of a wind turbine mast. The device can also be used for de-installation of the blade and possibly for other hoisting jobs related to an offshore wind turbine. Offshore wind turbines are in often mounted on a soil-bound foundation, e.g. on a monopile foundation, a jacket type foundation, etc. Installation of the blades, and potentially also of other components of the wind turbine, can be done using a crane on a vessel in floating condition or on a so-called jack-up type vessel. In the wind industry, floating foundations of offshore wind turbines are seen as most promising for the future demand of wind generated electrical power. Herein the installation and/or de-installation of blades is more complex to be performed at the offshore location. In particular, at sea the installation of a blade is challenging, taking into account that nowadays wind turbine blades having a length of more than 60 meters have become prominent. Blade lengths of 100 meters and more are also envisaged, e.g. for wind turbines of more than 10 MW, e.g. 15 MW or even 20 MW as currently being designed. For example, the Vestas V236-15.0 MW wind turbine has blade of about 115 metres. The hub height of such large capacity wind turbines is also very significant, e.g. over 120 meters. A horizontal axis rotational hub of a sizable offshore wind turbine, e.g. of several megawatts, commonly has three blade mounting structures. Each blade mounting structure commonly includes a bearing allowing for variation of the pitch angle of the blade. The bearing commonly has a ring, e.g. an outer ring, attached to the hub body and a ring, e.g. an inner ring, to be attached to a root end of the rotor blade. In the industry a bolted connection between the root end of the blade and the blade mounting structure, e.g. the inner ring of the bearing, is the common standard. Nowadays a T-bolt fastening arrangement is often employed. The bolted connection commonly involves a circular array of long bolts extending from a stern face of the root end of the blade, with the blade mounting structure having a corresponding array of bolt holes in which the bolts are to be received. A nut is then commonly tightened on each bolt. Introducing the multitude of bolts simultaneously into the bolt holes requires an accurate alignment of the wind turbine blade relative to the blade mounting structure, which is already challenging due to the size and weight of the blade, wind effects, etc. Also, at sea, the nacelle and its hub can be subject to motion, e.g. due to waves and/or waves acting on the wind turbine. In the industry it is commonly known to use a jack-up vessel with a major crane that is used to install the blades of the offshore wind turbine having a soil bound foundation. For example, reference is made to WO2014/125461. WO2012/002809 discloses a jack-up vessel equipped with a lifting device that is configured to autonomously position a wind turbine blade in such a way that it can be mounted on a wind turbine tower. The lifting device comprises a pivotal boom structure and a positioning device which can be displaced along the boom. WO2020/085902 discloses a vessel that is to be used in floating condition when installing a blade on an offshore wind turbine. The vessel is equipped with a lifting device for the blade that is dedicated to the six-o'clock installation of a wind turbine blade on the horizontal axis rotational hub. The lifting device has a pivotal boom and a wind turbine blade root end spatial orienting and support device with multiple actuators allowing multiple degrees of freedom of the movable blade root end retainer. Using this lifting device wind turbine blade is brought in a generally vertical orientation and underneath the blade mounting structure of the hub. in said six-o'clock position. The challenge is further increased when the wind turbine is installed using a vessel in floating condition, so subject to sea-induced motion during the installation. Floating foundations are envisaged e.g. in deeper water, where also the vessel will be floating as the depth is too much for a jack-up type vessel. In a floating foundation situation, the wind turbine mast may be significantly affected by the sea state during blade installation, e.g. depending on the actual design of the foundation. A known approach for installation of floating foundation offshore wind turbines is to perform the entire installation not at sea where the offshore turbine is to be moored, but in a sheltered location, e.g. in a port, estuary, fjord. Reference is made to the Hywind project, wherein complete installation was done in a fjord in Norway. Here the mast and nacelle were erected on shore and the blades were attached using land-based cranes. Then the entire assembly was lifted by a major cr