Methods of installing a mechanical damper apparatus

It is provided methods of installing a mechanical damper apparatus to an external surface of a tower of a wind turbine, the tower being in an erect state.

The present disclosure relates generally to methods of installing a mechanical damper apparatus to a tower of a wind turbine, and more particularly, to methods of installing a mechanical damper apparatus to a tower of a wind turbine when the tower is in an erect state.

BACKGROUND

Generally, a wind turbine includes a turbine that has a rotor that includes a rotatable hub assembly having multiple blades. The blades transform wind energy into a mechanical rotational torque that drives one or more generators via the rotor. The generators are sometimes, but not always, rotationally coupled to the rotor through a gearbox. The gearbox steps up the inherently low rotational speed of the rotor for the generator to efficiently convert the rotational mechanical energy to electrical energy, which is fed into a utility grid via at least one electrical connection. Gearless direct drive wind turbines also exist. The rotor, generator, gearbox and other components are typically mounted within a housing, or nacelle, that is positioned on top of a base that may be a truss or tubular tower.

Wind turbine towers, in specific contexts, are at risk of vortex-induced vibrations. Vortex-induced vibrations are structural vibrations that can occur due to the shedding of flow vortices when a fluid flow passes around a structure. Increasing rotor height and diameter of wind turbines makes vortex-induced vibrations increasingly important.

Vortex-induced vibrations are important when the tower does not have the rotor-nacelle assembly or a substantial portion thereof, for example, when the tower is stored or transported erect, during installation process before the installation of the rotor-nacelle assembly, or during service such as during retrofits, or maintenance when the rotor-nacelle assembly, or a major portion thereof, is absent. During these times, the tower acts as a beam clamped at one of its ends and subjected to a wind flow. Because of the vortex shedding developing in the tower wake, the tower may start to oscillate.

Mechanical dampers, e.g. tuned mass damper, are used to mitigate vortex-induced vibrations. In the cases where the tower does not have a pre-fitted mechanical damper, one can be installed. Improvements to the practical realization of mechanical dampers, e.g. to the process of fitting a mechanical damper, would create benefit for existing wind turbines, and future wind turbines. For example, if a quick and easy method of installing a mechanical damper is available, then any need for pre-fitted mechanical dampers is even reduced. The subject-matter described herein, is intended to provide improved methods of installing a mechanical damper apparatus to a tower of a wind turbine, and in particular, improved methods of installing a mechanical damper apparatus to a tower of a wind turbine when the tower is in an erect state.

BRIEF DESCRIPTION

According to an aspect, there is provided a method of installing a mechanical damper apparatus to an external surface of a tower of a wind turbine, the tower being in an erect state, the method including: passing a first rope-type guide element through a first receiving opening arranged at a first fixing point on the external surface of the tower, the first fixing point being for mounting the mechanical damper apparatus, at a mounting position, to the external surface of the tower; and while keeping the first rope-type guide element passed through the first receiving opening, performing the following: lowering a first end portion of the first rope-type guide element to a first height position lower than the first fixing point; attaching the first end portion of the first rope-type guide element to a protruding portion of a first connector of the mechanical damper apparatus, the first connector being configured for mating with the first receiving opening; and lifting the mechanical damper apparatus, and mounting the mechanical damper apparatus to the external surface of the tower; wherein mounting the mechanical damper apparatus to the tower includes guiding the protruding portion of the first connector into the first receiving opening by tensioning the first rope-type guide element.

According to a further aspect, there is provided a method of installing a mechanical damper apparatus to an external surface of a tower of a wind turbine, the tower being in an erect state, the method including: passing a first rope-type guide element through a receiving portion of a fourth connector; and while keeping the first rope-type guide element passed through the receiving portion of the fourth connector, performing the following: attaching a first end portion of the first rope-type guide element to a protruding portion of a third connector of the mechanical damper apparatus, the third connector configured for mating with the fourth connector, and attaching the fourth connector to a first rope-type hoist element; lifting the fourth connector, using the first rope-type hoist element, to a first receiving opening arranged at a first fixing point on the external surface of the tower, the first fixing point being for mounting the mechanical damper apparatus, at a mounting position, to the external surface of the tower; fixing the fourth connector to the tower at the first fixing point; and lifting the mechanical damper apparatus, and mounting the mechanical damper apparatus to the external surface of the tower; wherein mounting the mechanical damper apparatus to the tower includes guiding the protruding portion of the third connector into the receiving portion of the fourth connector by tensioning the first rope-type guide element.

These and other aspects, embodiments, examples and advantages of the present invention will become better understood with reference to the following description and appended claims.

DETAILED DESCRIPTION

Reference now will be made in detail to embodiments, one or more examples of which are illustrated in the drawings. Each example is provided for explaining the present disclosure. Features illustrated or described as part of one example or embodiment can be used with another example or embodiment.

As discussed above, the present disclosure relates to methods of installing a mechanical damper apparatus to a tower of a wind turbine, and in particular, improved methods of installing a mechanical damper apparatus to a tower of a wind turbine when the tower is in an erect state.

Accordingly, the present disclosed methods are especially beneficial during periods in which a wind turbine tower temporarily requires protection from undesirable oscillations, e.g. vortex-induced vibrations. Such temporary periods may for example be periods in which a wind turbine tower is stored (e.g. at quay side) or transported erect (e.g. on a ship), periods between the erection of the wind turbine tower and the installation of the nacelle/rotor blades, and periods in which a nacelle/rotor blades are removed (e.g. for maintenance/retrofit).

Even more particularly, the present disclosure relates to methods of installing a mechanical damper apparatus to an external surface of a tower of a wind turbine. Accordingly, a time period during which the wind turbine tower is unprotected from undesirable oscillations, in particular vortex-induced vibrations, can be reduced.

In general, a mechanical damper apparatus as described herein may be understood as a friction damper and/or a tuned mass damper. A mechanical damper apparatus as described herein may be understood as being configured for damping transverse oscillations and/or vortex induced vibrations.

In an example, a mechanical damper apparatus is installed to a tower of a wind turbine, e.g. mounted at a mounting position, for damping a (e.g. first or second) mode of vibration of the tower.

According to an aspect, there is provided a method of installing a mechanical damper apparatus110to an external surface of a tower120of a wind turbine, the tower120being in an erect state, the method including: passing1010a first rope-type guide element130through a first receiving opening140arranged at a first fixing point on the external surface of the tower120, the first fixing point being for mounting the mechanical damper apparatus110, at a mounting position, to the external surface of the tower120; and while keeping the first rope-type guide element130passed through the first receiving opening140, performing the following: lowering1020a first end portion of the first rope-type guide element130to a first height position lower than the first fixing point; attaching1030the first end portion of the first rope-type guide element130to a protruding portion of a first connector150of the mechanical damper apparatus110, the first connector150being configured for mating with the first receiving opening140; and lifting1040the mechanical damper apparatus110, and mounting1050the mechanical damper apparatus110to the external surface of the tower120; wherein mounting1050the mechanical damper apparatus110to the tower120includes guiding the protruding portion of the first connector150into the first receiving opening140by tensioning the first rope-type guide element130.

Installing a mechanical damper apparatus110to an external surface of a tower120of a wind turbine, may be understood as installing the mechanical damper apparatus110such that the mechanical damper apparatus110is fixed to an outside portion of the tower120.

The mechanical damper apparatus110may be understood to be configured to damp oscillations of the tower120, when installed to an external surface of the tower120.

An erect state may be understood as a state where the tower (or a portion of the tower) is in an upright or standing orientation, or the tower (or a portion of the tower) is oriented such that the axis of the tower is substantially parallel to (e.g. within 5 or 10 degrees of) a direction of gravity, either temporarily (e.g. storage, transport, and/or prior to being in service/in operation; or permanently (e.g. constructed, commissioned, ready for service/in operation, and/or in service/in operation).

According to an embodiment, passing1010a first rope-type guide element130through a first receiving opening140may be understood as threading or sliding, one end (e.g. a first end) of the first rope-type guide element130through the first receiving opening140.

The first receiving opening140can be understood as an opening configured to receive or mate with a protruding portion of a first connector150of the mechanical damper apparatus110.

For example, the first receiving opening140is a through-hole in the tower120configured for receiving the protruding portion of the first connector150. The first connector150and the first receiving opening140can be understood as being configured for mating with each other.

In an example, the first connector150is a pin-type element, and the first receiving opening140is an eyebolt-type element. In a further example, the first connector150may be a male-type connector and the first receiving opening140may be a female-type connector.

As an illustrative example, the first connector150may be a bolt or bolt-type connector, or the protruding portion of the first connector150may be the threaded portion and/or shank portion of a bolt or bolt-type connector.

As a further illustrative example, the first receiving opening140may be a through-hole in the tower, e.g. a wall portion of the tower, having dimension(s) (e.g. diameter, length) for receiving the threaded portion and/or shank portion of a bolt or bolt-type connector.

As can be understood by the skilled person, other connection devices can be used in place of a bolt or bolt-type connector, for example, a clevis pin-type connector (which may be secured by a split pin-type securing device).

According to an embodiment, the first fixing point on the external surface of the tower120for mounting the mechanical damper apparatus110is such that the mechanical damper apparatus110when mounted to the tower120at (at least) the first fixing point, the mechanical damper apparatus is designed or determined to (optimally or maximally) reduce transverse oscillations and/or vortex-induced vibrations.

According to an embodiment, the first rope-type guide element130can be understood to be an element configured for guiding the protruding portion of the first connector150into the first receiving opening140.

According to an embodiment, the first rope-type guide element130is a guide element having a form of a rope, string, cable, cord and/or wire. In an example, the first rope-type guide element130is a rope, a string, a cable, a cord, a chain, a twine, a thread and a wire.

In an example, the first rope-type guide element130has a diameter less than a diameter of the first receiving opening140. In an example, the first rope-type guide element130has a length at least 50% of a height of the tower120, preferably at least 75% of a height of the tower120, or more preferably at least a height of the tower120.

The first height position to which the first end portion of the first rope-type guide element130is lowered1020to may be understood as a position nearer to ground level or sea level, or nearer to a base of the tower120, relative to the first fixing point. In an example, the first height position is a position at a base portion of the tower120or within 10 m of a base of the tower120.

According to an embodiment, attaching1030the first end portion of the first rope-type guide element130to the protruding portion of the first connector150of the mechanical damper apparatus110may be understood as reversibly or non-permanently attaching the first end portion of the first rope-type guide element130to the protruding portion of the first connector150of the mechanical damper apparatus110.

For example, the first end portion of the first rope-type guide element130may include a hook-type end attachment, and the protruding portion of the first connector150of the mechanical damper apparatus110may include an eyebolt-type attachment, such that the hook-type end attachment of the first rope-type guide element130may be reversibly or non-permanently attached to the eyebolt-type attachment of the protruding portion of the first connector150of the mechanical damper apparatus110.

As can be understood by the skilled person, other methods of attachment can be used, for example other reversible/non-permanent attachment methods (e.g. the protruding portion of the first connector150having an eyebolt, and tying/knotting the first end portion of the first rope-type guide element130to the eyebolt of the protruding portion of the first connector150), or permanent attachment methods (e.g. adhesive) or semi-permanent attachment methods (e.g. adhesive tape).

Lifting1040the mechanical damper apparatus110may be understood as a carrying a majority portion of the weight of the mechanical damper apparatus110in an upwards direction, e.g. from a base portion of the tower120towards the first fixing point. In an example, the mechanical damper apparatus110may be lifted using a lifting apparatus, e.g. a crane.

Mounting1050the mechanical damper apparatus110to the external surface of the tower120may be understood as reversibly or non-permanently mounting the mechanical damper apparatus110to the external surface of the tower120. For example, the mechanical damper apparatus110may be bolted onto the external surface of the tower120.

Guiding the protruding portion of the first connector150to the first receiving opening140by tensioning the first rope-type guide element130may be understood to effect a (pulling) force on the protruding portion of the first connector150towards the first receiving opening140.

It may be understood that during mounting1050of the mechanical damper apparatus110to the tower120, an alignment of the first connector150of the mechanical damper apparatus110and the first receiving opening140is provided by a combination of a tension of the first rope-type guide element130, and the first rope-type guide element130being in a state of passed through the first receiving opening140, and the first rope-type guide element130being attached at the first end portion of the first rope-type guide element130to the protruding portion of the first connector150.

Accordingly, the protruding portion of the first connector150may be guided into the first receiving opening140, by an operator, easily, e.g. when view is partially or fully obstructed (e.g. without direct line of sight), and/or when the operator and mechanical damper apparatus are distant or remote from each other. Further, the mounting operation may be carried out remotely, e.g. from the ground and/or from inside the tower. Thus, an improved method of installation is provided.

According to an embodiment, the method includes, after guiding the portion of the first connector150into the first receiving opening140, securing the first connector150to the tower120from inside the tower120.

For example, the first connector150may extend through a wall of the tower120such that an operator on the inside of the tower120may secure the first connector150to the tower120.

In a further example, the first receiving opening140, and/or the first connector150after being guided into the first receiving opening140, may be accessible from an operator on the inside of the tower120, e.g. via an access opening in the tower120, such as a window or door within the tower120.

According to an embodiment, mounting1050the mechanical damper apparatus110to the tower120includes securing the protruding portion of the first connector150within the first receiving opening140.

For example, where the protruding portion of the first connector150is a bolt-type connector, an operator may secure the first connector150to the tower120using a nut-type securing device.

In a further example, where the protruding portion of the first connector150is a clevis pin-type connector, an operator may secure the first connector150to the tower120using a split pin-type securing device.

According to an embodiment, tensioning the first rope-type guide element130includes pulling on a second end portion of the first rope-type guide element130, thereby increasing a tension of the first rope-type guide element130.

It may be understood that a (guiding) force on the protruding portion of the first connector150effected by tension of the first rope-type guide element130is in the direction of the first receiving opening140.

According to an embodiment, lowering1020the first end portion of the first rope-type guide element130to a first height position lower than the first fixing point includes letting out the first rope-type guide element130from inside the tower120.

In an example, an operator inside the tower120may lower1020the first end portion of the first rope-type guide element130to the first height position.

In a further example, the first end portion of the first rope-type guide element130is lowered1020to the first height while keeping the first rope-type guide element130passed through the first receiving opening140.

It may be understood that lowering1020the first end portion of the first rope-type guide element130, facilitates a positioning of the first end portion of the first rope-type guide element130for being (easily) attached to the protruding portion of the first connector150, e.g. positions the first end portion of the first rope-type guide element130in proximity to the mechanical damper apparatus110, e.g. at a base area of the tower120, e.g. at substantially ground level or sea level.

According to an embodiment, the mechanical damper apparatus110includes a plurality of connectors150,350. According to an embodiment, there are a plurality of rope-type guide elements130,330for guiding a plurality of connectors150,350into a plurality of receiving openings140,340.

According to an embodiment, the mechanical damper apparatus110includes a second connector350configured for mating with a second receiving opening340. According to an embodiment, the second receiving opening340is arranged at a second fixing point, the second fixing point being for mounting the mechanical damper apparatus110, at the mounting position, to the external surface of the tower120.

According to an embodiment, a method provided includes passing a second rope-type guide element330through the second receiving opening340; and while keeping the second rope-type guide element330passed through the second receiving opening340, and prior to the lifting1040of the mechanical damper apparatus110, and prior to the mounting1050of the mechanical damper apparatus110to the tower120, performing the following: lowering a first end portion of the second rope-type guide element330to a second height position lower than the second fixing point; and attaching the first end portion of the second rope-type guide element330to a protruding portion of the second connector350; wherein mounting1050the mechanical damper apparatus110to the tower120includes: while guiding the protruding portion of the first connector150into the first receiving opening140, guiding the protruding portion of the second connector350into the second receiving opening340by tensioning the second rope-type guide element330.

The embodiments/examples relating to the first connector150as described herein, may be understood to apply, mutatis mutandis, to the second connector350.

The second connector350may be understood to be arranged proximate to the first connector150. The second connector350may be understood to be provided on (the same side of) the mechanical damper apparatus110as the first connector150.

The embodiments/examples relating to the first receiving opening140as described herein, may be understood to apply, mutatis mutandis, to the second receiving opening340.

The second receiving opening340may be understood to be arranged proximate to the first receiving opening140. The second receiving opening340may be understood to be provided on (the same side of) the tower120as the first receiving opening140.

The embodiments/examples relating to the first fixing point as described herein, may be understood to apply, mutatis mutandis, to the second fixing point.

The second fixing point may be understood to be arranged proximate to the first fixing point. The second fixing point may be understood to be provided on (the same side of) the tower120as the first fixing point.

The embodiments/examples relating to the first rope-type guide element130as described herein, may be understood to apply, mutatis mutandis, to the second rope-type guide element330. The second rope-type guide element330may be understood to be arranged proximate to the first rope-type guide element130.

According to an embodiment, lowering the first end portion of the second rope-type guide element330to a second height position lower than the second fixing point includes letting out the second rope-type guide element330from inside the tower120.

In an example, an operator inside the tower120may lower the first end portion of the second rope-type guide element330to the second height position.

In a further example, the first end portion of the second rope-type guide element330is lowered to the second height while keeping the second rope-type guide element330passed through the second receiving opening340.

It may be understood that lowering the first end portion of the second rope-type guide element330, facilitates a positioning of the first end portion of the second rope-type guide element330for being (easily) attached to the protruding portion of the second connector350.

For example, lowering the first end portion of the second rope-type guide element330positions the first end portion of the first rope-type guide element130in proximity to the mechanical damper apparatus110, e.g. at a base area of the tower120, e.g. at substantially ground level or sea level.

The second height position may be understood to be substantially the same as the first height position.

According to an embodiment, attaching the first end portion of the second rope-type guide element330to the protruding portion of the second connector350of the mechanical damper apparatus110may be understood as reversibly or non-permanently attaching the first end portion of the second rope-type guide element330to the protruding portion of the second connector350of the mechanical damper apparatus110.

For example, the first end portion of the second rope-type guide element330may include a hook-type end attachment, and the protruding portion of the second connector350of the mechanical damper apparatus110may include an eyebolt-type attachment, such that the hook-type end attachment of the second rope-type guide element330may be reversibly or non-permanently attached to the eyebolt-type attachment of the protruding portion of the second connector350of the mechanical damper apparatus110.

As can be understood by the skilled person, other methods of attachment can be used, for example other reversible/non-permanent attachment methods (e.g. the protruding portion of the second connector350having an eyebolt, and tying/knotting the first end portion of the second rope-type guide element330to the eyebolt of the protruding portion of the second connector350, or permanent attachment methods (e.g. adhesive or semi-permanent attachment methods (e.g. adhesive tape).

Guiding the protruding portion of the second connector350to the second receiving opening340by tensioning the second rope-type guide element330may be understood to effect a (pulling force on the protruding portion of the second connector350towards the second receiving opening340.

It may be understood that during mounting1050of the mechanical damper apparatus110to the tower120, an alignment of the second connector350of the mechanical damper apparatus110and the second receiving opening340is provided by a combination of a tension of the second rope-type guide element330, and the second rope-type guide element330being in a state of passed through the second receiving opening340, and the second rope-type guide element330being attached at the first end portion of the second rope-type guide element330to the protruding portion of the second connector350.

Accordingly, the protruding portion of the second connector350may be guided into the second receiving opening340, by an operator, easily, e.g. when view is partially or fully obstructed (e.g. without direct line of sight, or when the operator and mechanical damper apparatus are distant or remote from each other. Further, the mounting operation may be carried out remotely, e.g. from the ground and/or from inside the tower. Thus, an improved method of installation is provided.

According to a further aspect, there is provided a method of installing a mechanical damper apparatus110to an external surface of a tower120of a wind turbine, the tower120being in an erect state, the method including: passing1110a first rope-type guide element130through a receiving portion of a fourth connector460; and while keeping the first rope-type guide element130passed through the receiving portion of the fourth connector460, performing the following: attaching1120a first end portion of the first rope-type guide element130to a protruding portion of a third connector450of the mechanical damper apparatus110, the third connector450configured for mating with the fourth connector460, and attaching1130the fourth connector460to a first rope-type hoist element430; lifting1140the fourth connector460, using the first rope-type hoist element430, to a first receiving opening140arranged at a first fixing point on the external surface of the tower120, the first fixing point being for mounting the mechanical damper apparatus110, at a mounting position, to the external surface of the tower120; fixing1150the fourth connector460to the tower120at the first fixing point; and lifting1160the mechanical damper apparatus110, and mounting1170the mechanical damper apparatus110to the external surface of the tower120; wherein mounting1170the mechanical damper apparatus110to the tower120includes guiding the protruding portion of the third connector450into the receiving portion of the fourth connector460by tensioning the first rope-type guide element130.

According to an embodiment, passing1110a first rope-type guide element130through a receiving portion of the fourth connector460may be understood as threading or sliding, one end (e.g. a first end) of the first rope-type guide element130through the receiving portion of the fourth connector460.

The fourth connector460can be understood to be configured to connect the mechanical damper apparatus110to the tower120.

According to an embodiment, the third connector450being configured for mating with the fourth connector460can be understood as the receiving portion of the fourth connector460being configured for receiving the protruding portion of the third connector450of the mechanical damper apparatus110.

For example, (the receiving portion of) the fourth connector460may be an eyebolt-type element and (the protruding portion of) the third connector450may be a pin-type element.

In another example, the third connector includes a male-type connector and the fourth connector460includes a female-type connector.

As an illustrative example, (the receiving portion of) the fourth connector460has dimension(s) (e.g. diameter, length) for receiving the (the protruding portion of) the third connector450.

As can be understood by the skilled person, other elements can be used in place of a pin-type element and an eyebolt-type element, as (the protruding portion of) the third connector450and (the receiving portion of) the fourth connector460, respectively.

For example, a hook-type element or eyebolt-type element, and a peg-type element, as (the protruding portion of) the third connector450and (the receiving portion of) the fourth connector460, respectively.

In an example, the third connector includes a female-type connector and the fourth connector460includes a male-type connector.

As may be understood by the skilled person, where connectors or elements are described to mate with each other, or connect with each other, the connectors or elements may be exchanged, or swapped, with each other, whilst still achieving the mating or connecting functionality.

According to an embodiment, attaching1120the first end portion of the first rope-type guide element130to a protruding portion of the third connector450of the mechanical damper apparatus110may be understood as reversibly or non-permanently attaching the first end portion of the first rope-type guide element130to a protruding portion of the third connector450of the mechanical damper apparatus110.

For example, the first end portion of the first rope-type guide element130may include a hook-type end attachment, and the protruding portion of the third connector450of the mechanical damper apparatus110may include an eyebolt-type attachment, such that the hook-type end attachment of the first rope-type guide element130may be reversibly or non-permanently attached to the eyebolt-type attachment of the protruding portion of the third connector450of the mechanical damper apparatus110.

As can be understood by the skilled person, other methods of attachment can be used, for example other reversible/non-permanent attachment methods (e.g. the protruding portion of the third connector450having an eyebolt, and tying/knotting the first end portion of the first rope-type guide element130to the eyebolt of the protruding portion of the third connector450), or permanent attachment methods (e.g. adhesive) or semi-permanent attachment methods (e.g. adhesive tape).

In an example, the first rope-type guide element130has a diameter less than a diameter of the first receiving portion of the fourth connector460. In an example, the first rope-type guide element130has a length at least a height of the tower120, preferably at least 150% of a height of the tower120, or more preferably at least twice a height of the tower120.

According to an embodiment, attaching1130the fourth connector460to the first rope-type hoist element430may be understood as reversibly or non-permanently attaching the fourth connector460to the first rope-type hoist element430.

For example, the first rope-type hoist element430may be attached to the fourth connector460using reversible/non-permanent methods (as described further herein), using permanent attachment methods (e.g. adhesive) or using semi-permanent attachment methods (e.g. adhesive tape).

In an example of a reversible/non-permanent method, the first rope-type hoist element430includes a hook-type end attachment (e.g. arranged at a first end portion of the first rope-type hoist element430) which is configured to attach to the fourth connector460, e.g. to an eyelet portion of the fourth connector460(the eyelet portion may be separate from the receiving portion, e.g. the eyelet portion may be arranged on an opposite end of the fourth connector460to the receiving portion), or e.g. to the receiving portion of the fourth connector460.

In another example of a reversible/non-permanent method, the first rope-type hoist element430may be tied/knotted (e.g. at a first end portion of the first rope-type hoist element430) to the receiving portion of the fourth connector460.

Lifting1140the fourth connector460, using the first rope-type hoist element430, to the first receiving opening140may be understood as a lifting the fourth connector460(e.g. without lifting the mechanical damper apparatus110), while keeping the first rope-type guide element130passed through the receiving portion of the fourth connector460.

Lifting1140the fourth connector460may be understood as lifting in an upwards direction, e.g. from a base portion of the tower120towards the first fixing point. In an example, the fourth connector460may be lifted by pulling or drawing (e.g. from a second end portion of the first rope-type hoist element).

In an example, the first rope-type hoist element430has a diameter less than a diameter of the first receiving opening140. In an example, the first rope-type hoist element430has a length at least 50% of a height of the tower120, preferably at least 75% of a height of the tower120, or more preferably at least a height of the tower120.

A height of the tower120may be understood as a hub height of the wind turbine, or a height from a base of the tower120to the top of the tower120.

According to an embodiment, fixing1150the fourth connector460to the tower120at the first fixing point includes securing the fourth connector460within the first receiving opening140. In an example, fixing1150the fourth connector460to the tower120at the first fixing point includes tensioning or pulling the first rope-type hoist element430such that (an end portion opposite to the receiving portion of) the fourth connector460enters the first receiving opening140(first).

In an example, fixing the fourth connector460to the tower120at the first fixing point includes, where an end portion of the fourth connector460is a bolt-type end portion, securing the fourth connector460within the first receiving opening140using a nut-type device.

Mounting1170the mechanical damper apparatus110to the tower120may be understood as reversibly or non-permanently mounting the mechanical damper apparatus110to the external surface of the tower120. For example, the mechanical damper apparatus110may be bolted onto the external surface of the tower120.

Guiding the protruding portion of the third connector450into the receiving portion of the fourth connector460by tensioning the first rope-type guide element130may be understood to effect a (pulling) force on the protruding portion of the third connector450towards (the receiving portion of) the fourth connector460.

It may be understood that during mounting1170of the mechanical damper apparatus110to the tower120, an alignment of the third connector450of the mechanical damper apparatus110and (the receiving portion of) the fourth connector460is provided by a combination of a tension of the first rope-type guide element130, and the first rope-type guide element130being in a state of passed through the receiving portion of the fourth connector460, and the first rope-type guide element130being attached at the first end portion of the first rope-type guide element130to the protruding portion of the third connector450.

Accordingly, the protruding portion of the third connector450may be guided into the receiving portion of the fourth connector460, by an operator, easily, e.g. when view is partially or fully obstructed (e.g. without direct line of sight), and/or when the operator and mechanical damper apparatus are distant or remote from each other. Further, the mounting operation may be carried out remotely, e.g. from the ground and/or from inside the tower. Thus, an improved method of installation is provided.

According to an embodiment, the receiving portion of the fourth connector460is a ring-type element or eyebolt-type element and the protruding portion of the third connector450is a pin-type element.

According to an embodiment, mounting1170the mechanical damper apparatus110includes lowering the protruding portion of the third connector450into the receiving portion of the fourth connector460.

According to an embodiment, the method includes supporting a weight of the mechanical damper apparatus110on at least the fourth connector460.

In an example, a protruding portion of the fourth connector460may extend through a wall of the tower120(after the fourth connector460is fixed1150to the tower120) such that a load may be transferred via the fourth connector460to the tower120.

In a further example, the mechanical damper apparatus110may be lowered into the receiving portion of the fourth connector460by operation of a lifting apparatus carrying a weight of the mechanical damper apparatus110and/or tensioning of the first rope-type guide element130.

According to an embodiment, fixing1150the fourth connector460to the tower120includes fixing the fourth connector460to the tower120from inside the tower120, and/or securing the fourth connector460within the first receiving opening140.

The first receiving opening140can be understood as an opening configured to receive or mate with a protruding portion of the fourth connector460. For example, the first receiving opening140is a through-hole in the tower120configured for receiving the protruding portion of the fourth connector460.

The fourth connector460and the first receiving opening140can be understood as being configured for connecting with each other. In an example, the fourth connector460may include a male-type connector and the first receiving opening140may be a female-type connector.

As an illustrative example, the fourth connector460may include a threaded portion and/or shank portion of an eyebolt-type element.

As a further illustrative example, the first receiving opening140may be a through-hole in the tower, e.g. a wall portion of the tower, having dimension(s) (e.g. diameter, length) for receiving the threaded portion and/or shank portion of an eyebolt-type element of the fourth connector460.

As can be understood by the skilled person, other connection devices can be used in place of a threaded portion and/or shank portion of an eyebolt-type element, for example, a clevis pin-type connector (which may be secured by a split pin-type securing device).

According to an embodiment, tensioning the first rope-type guide element130includes pulling a second end portion of the first rope-type guide element130, from a first height position lower than the first fixing point.

In an example, tensioning the first rope-type guide element130includes pulling (a second end portion of) the first rope-type guide element130, from a first height position lower than the first fixing point.

In an example, the first height position may be understood as a position nearer to ground level or sea level, or nearer to a base of the tower120, relative to the first fixing point.

In an example, the first height position is a position at a base portion of the tower120or within 10 m of a base of the tower120.

According to an embodiment, the mechanical damper apparatus110includes a plurality of connectors450,750.

According to an embodiment, there are a plurality of rope-type guide elements130,330for guiding a plurality of connectors450,750into a plurality of receiving openings140,340.

According to an embodiment, the mechanical damper apparatus110includes a fifth connector750configured for mating with a sixth connector760.

According to an embodiment, the sixth connector760is configured to be fixed to the tower120(at a second fixing point).

According to an embodiment, a method provided includes passing a second rope-type guide element330through a receiving portion of the sixth connector760; and while keeping the second rope-type guide element330passed through the receiving portion of the sixth connector760, and prior to the lifting1160of the mechanical damper apparatus110, and prior to the mounting1170of the mechanical damper apparatus110to the tower120, performing the following: attaching a first end portion of the second rope-type guide element330to a protruding portion of the fifth connector750, and attaching the sixth connector760to a second rope-type hoist element; lifting the sixth connector760, using the first rope-type hoist element, to a second receiving opening340arranged at a second fixing point on the external surface of the tower120, the second fixing point being for mounting the mechanical damper apparatus110, at the mounting position, to the external surface of the tower120; and fixing the sixth connector760to the tower120at the second fixing point; wherein mounting1170the mechanical damper apparatus110to the tower120further includes: while guiding the protruding portion of the third connector450into the receiving portion of the fourth connector460, guiding the protruding portion of the fifth connector750into the receiving portion of the sixth connector760by tensioning the second rope-type guide element330.

The embodiments/examples relating to the third connector450as described herein, may be understood to apply, mutatis mutandis, to the fifth connector750.

The fifth connector750may be understood to be arranged proximate to the third connector450. The fifth connector750may be understood to be provided on (the same side of) the mechanical damper apparatus110as the third connector450.

The embodiments/examples relating to the fourth connector460as described herein, may be understood to apply, mutatis mutandis, to the sixth connector760.

According to an embodiment, attaching the first end portion of the second rope-type guide element330to the protruding portion of the fifth connector750of the mechanical damper apparatus110may be understood as reversibly or non-permanently attaching the first end portion of the second rope-type guide element330to the protruding portion of the fifth connector750of the mechanical damper apparatus110.

For example, the first end portion of the second rope-type guide element330may include a hook-type end attachment, and the protruding portion of the fifth connector750of the mechanical damper apparatus110may include an eyebolt-type attachment, such that the hook-type end attachment of the second rope-type guide element330may be reversibly or non-permanently attached to the eyebolt-type attachment of the protruding portion of the fifth connector750of the mechanical damper apparatus110.

As can be understood by the skilled person, other methods of attachment can be used, for example other reversible/non-permanent attachment methods (e.g. the protruding portion of the fifth connector750having an eyebolt, and tying/knotting the first end portion of the second rope-type guide element330to the eyebolt of the protruding portion of the fifth connector750, or permanent attachment methods (e.g. adhesive or semi-permanent attachment methods (e.g. adhesive tape).

Guiding the protruding portion of the fifth connector750to the receiving portion of the sixth connector760by tensioning the second rope-type guide element330may be understood to effect a (pulling force on the protruding portion of the fifth connector750towards (the receiving portion of) the sixth connector760.

It may be understood that during mounting1170of the mechanical damper apparatus110to the tower120, an alignment of the fifth connector750of the mechanical damper apparatus110and (the receiving portion of) the sixth connector760is provided by a combination of a tension of the second rope-type guide element330, and the second rope-type guide element330being in a state of passed through the receiving portion of the sixth connector760, and the second rope-type guide element330being attached at the first end portion of the second rope-type guide element330to the protruding portion of the fifth connector750.

Accordingly, the protruding portion of the fifth connector750may be guided into the receiving portion of the sixth connector760, by an operator, easily, e.g. when view is partially or fully obstructed (e.g. without direct line of sight, or when the operator and mechanical damper apparatus are distant or remote from each other.

Further, the mounting operation may be carried out remotely, e.g. from the ground and/or from inside the tower. Thus, an improved method of installation is provided.

According to an embodiment, the lifting1040,1160of the mechanical damper apparatus110is performed using a lifting apparatus310.

According to an embodiment, after mounting1050,1170the mechanical damper apparatus110to the tower120, remotely unhooking the mechanical damper apparatus110from the lifting apparatus310using a remotely controlled hook device320.

In an example, the operation of remotely unhooking the mechanical damper apparatus110from the lifting apparatus310may be performed from the ground and/or from inside the tower.

According to an embodiment, the method includes, following the mounting1050,1170of the mechanical damper apparatus110to the tower120, the method further includes removing at least a portion of a nacelle of the wind turbine.

In an example, the method includes, following the mounting1050,1170of the mechanical damper apparatus110to the tower120, the method further includes removing at least a portion of a nacelle of the wind turbine constituting, by weight, at least 25%, or at least 50% of a weight of the nacelle of the wind turbine.

In an illustrative example, the method is performed prior to removal of a nacelle of the wind turbine.

In an illustrative example, after mounting1050the mechanical damper apparatus110to the tower120, an axis of the first connector150is substantially horizontal.

In an illustrative example, a method as described herein is performed prior to removal of rotor blades of the wind turbine.

In an illustrative example, a method as described herein includes, after mounting1050,1170the mechanical damper apparatus110to the tower120, verifying a mounted condition of the mechanical damper apparatus110, using a borescope, from inside the tower120.

FIG.1is a diagrammatic rendering relating to the attaching1030of a first end portion of a first rope-type guide element130to a protruding portion of a first connector150of a mechanical damper apparatus110. As an illustrative example,FIG.1shows the lowered1020first end portion of the first rope-type guide element130ready for being attached1030to the protruding portion of the first connector150.

As illustrated, an operator may lower1020the first rope-type guide element130and/or keep the first rope-type guide element130passed through the first receiving opening140.

It may be understood that lowering1020the first rope-type guide element130and/or keeping the first rope-type guide element130may be carried out by an operator inside the tower120and/or outside the tower120at ground level, or anywhere else.

FIG.2is a diagrammatic rendering relating to the tensioning of a first rope-type guide element130. As an illustrative example,FIG.2shows the mechanical damper apparatus110ready to be mounted1170, wherein the mechanical damper apparatus110is shown to be in a state of being lifted, and the first rope-type guide element130in a state of being tensioned or about to be tensioned.

It may be understood that the first rope-type guide element130may (start to) be tensioned during lifting, such as to take up any slack in the first rope-type guide element130during lifting, or when the mechanical damper apparatus110is ready to be mounted1170or (only) during mounting1170of the mechanical damper apparatus110.

It may be understood that tensioning the first rope-type guide element130may be carried out by an operator inside the tower120and/or outside the tower120at ground level, or anywhere else.

It may be understood that the tension of the first rope-type guide element130facilitates alignment of the first connector150and the first receiving opening140, without requiring line-of-sight. Thus, an improved method of installation is provided.

FIG.3is a diagrammatic rendering relating to the lifting of a mechanical damper apparatus110. As an illustrative example,FIG.3shows the mechanical damper apparatus being lifted1040by a lifting apparatus310.

As an illustrative example,FIG.3shows a second rope-type guide element330passed through a second receiving opening340, the second rope-type guide element330attached at a first end of the second rope-type guide element330to a second connector350, according to embodiments described herein.

As an illustrative example,FIG.3shows a remotely controlled hook device320according to embodiments described herein.

According to embodiments described herein, the plurality of rope-type guide elements130,330particularly eases mounting of a mechanical damper apparatus110having a plurality of connectors150,350. It may be understood that the challenge of aligning a plurality of connections, especially from the ground, or from inside the tower120, is thus facilitated.

According to embodiments described herein, a remotely controlled hook device320facilitates the mounting of a mechanical damper apparatus110, as the lifting apparatus310may be disconnected remotely, e.g. from the ground.

Thus, an improved method of installation is provided.

FIG.4is a diagrammatic rendering relating to the attaching of a first rope-type hoist element430to a fourth connector460. As an illustrative example,FIG.4shows a first end portion of the first rope-type hoist element430ready for being attached1130to the fourth connector460.

As an illustrative example,FIG.4shows the first rope-type guide element130in a state of being passed1110through the receiving portion of the fourth connector460, and in a state of being attached1120at the first end portion of the first rope-type guide element130to the protruding portion of the third connector450.

FIG.5is a diagrammatic rendering relating to the lifting of a fourth connector460to a first receiving opening140arranged at a first fixing point on the external surface of the tower120. As an illustrative example,FIG.5shows the fourth connector460, ready to be fixed1150, or already fixed1150to the tower120, while the first rope-type guide element130is kept passed1110through the receiving portion of the fourth connector460, and while the first end portion of the first rope-type guide element130is attached1120to the protruding portion of the third connector450.

FIG.6is a diagrammatic rendering relating to the tensioning of a first rope-type guide element130. As an illustrative example,FIG.6shows the mechanical damper apparatus110ready to be mounted1170, wherein the mechanical damper apparatus110is shown to be in a state of being lifted, and the first rope-type guide element130in a state of being tensioned or about to be tensioned.

It may be understood that the first rope-type guide element130may (start to) be tensioned during lifting, such as to take up any slack in the first rope-type guide element130during lifting, or when the mechanical damper apparatus110is ready to be mounted1170or (only) during mounting1170of the mechanical damper apparatus110.

It may be understood that tensioning the first rope-type guide element130may be carried out by an operator outside the tower120at ground level, or anywhere else.

It may be understood that the tension of the first rope-type guide element130facilitates alignment of the protruding portion of the third connector450and the receiving portion of the fourth connector460, without requiring line-of-sight. Thus, an improved method of installation is provided.

FIG.7is a diagrammatic rendering relating to the lifting of a mechanical damper apparatus110. As an illustrative example,FIG.7shows the mechanical damper apparatus being lifted1160by a lifting apparatus310.

As an illustrative example,FIG.7shows a second rope-type guide element330passed through a receiving portion of a sixth connector760, the second rope-type guide element330attached at a first end of the second rope-type guide element330to a fifth connector750, according to embodiments described herein.

As an illustrative example,FIG.7shows a remotely controlled hook device320according to embodiments described herein.

According to embodiments described herein, the plurality of rope-type guide elements130,330particularly eases mounting of a mechanical damper apparatus110having a plurality of connectors450,750. It may be understood that the challenge of aligning a plurality of connections, especially from the ground, or from inside the tower120, is thus facilitated.

Thus, an improved method of installation is provided.

FIG.8is an illustration depicting a protruding portion of the third connector450and a receiving portion of the fourth connector460. As an illustrative example, the third connector450is shown to be of the mechanical damper apparatus110, and the fourth connector460is shown fixed to the tower120.

FIG.9is an illustration depicting a remotely controlled hook device320and a mounted mechanical damper apparatus110. As an illustrative example, the mechanical damper apparatus110is shown to be already mounted1050,1170to the tower120, and the remotely controlled hook device320about to be remotely operated to remotely unhook the mechanical damper apparatus110from a lifting apparatus310(not shown).

FIG.10is a diagram of a method of installing a mechanical damper apparatus110to an external surface of a tower120of a wind turbine.FIG.10shows the method including passing1010a first rope-type guide element130through a first receiving opening140, lowering1020a first end portion of the first rope-type guide element130to a first height position, attaching1030the first end portion of the first rope-type guide element130to a protruding portion of a first connector150of a mechanical damper apparatus110, and lifting1040the mechanical damper apparatus110, and mounting1050the mechanical damper apparatus110to the tower120, according to an aspect described herein.

It may be understood that tensioning the first rope-type guide element130(as part of mounting1050the mechanical damper apparatus110to the tower120) may be performed before or after or concurrently with lifting1040the mechanical damper apparatus110.

FIG.11is a diagram of a method of installing a mechanical damper apparatus110to an external surface of a tower120of a wind turbine.FIG.11shows the method including passing1110a first rope-type guide element130through a receiving portion of a fourth connector460, attaching1120a first end portion of the first rope-type guide element130to a protruding portion of a third connector450of the mechanical damper apparatus110, and attaching1130the fourth connector460to a first rope-type hoist element430, lifting1140the fourth connector460to a first receiving opening140, fixing1150the fourth connector460to the tower120, and lifting1160the mechanical damper apparatus110, and mounting1170the mechanical damper apparatus110to the tower120, according to an aspect described herein.

It may be understood that attaching1120the first end portion of the first rope-type guide element130to the protruding portion of the third connector450of the mechanical damper apparatus110, may be performed before or after or concurrently with attaching1130the fourth connector460to the first rope-type hoist element430.

It may be understood that tensioning the first rope-type guide element130(as part of mounting1170the mechanical damper apparatus110to the tower120) may be performed before or after or concurrently with lifting1160the mechanical damper apparatus110.

According to an example, it is described de-mounting the mechanical damper apparatus110from the external surface of the tower120.

In an example, de-mounting the mechanical damper apparatus110includes guiding the protruding portion of the first connector150out of the first receiving opening140, e.g. by pushing (from inside the tower120) or by pulling using a further rope-type guide element.

In an example, de-mounting the mechanical damper apparatus includes guiding the protruding portion of the third connector450out of the receiving portion of the fourth connector460, e.g. by pushing (from inside the tower120) or by pulling using a further rope-type guide element.

In an example, the further rope-type guide element is attached at a first end portion of the further rope-type guide element to the mechanical damper apparatus110, and may be pulled from a second end portion of the further rope-type guide element. In an example, the further rope-type guide element is operated/pulled, via at least one pulley element, from a height position lower than the first fixing point.

In an example, de-mounting the mechanical damper apparatus110includes releasing (or un-securing) the first connector150from the tower120from inside the tower120and/or releasing (or un-securing) the protruding portion of the first connector150from within the first receiving opening140.

In an example, de-mounting the mechanical damper apparatus110includes releasing (or un-fixing) the fourth connector460from the tower120from inside the tower120and/or releasing (or un-securing) the fourth connector460from within the first receiving opening140.

In an example, de-mounting the mechanical damper apparatus110includes supporting a weight of the mechanical damper apparatus110(during releasing (or un-securing) the first connector150from the tower120, and/or during guiding the protruding portion of the first connector110out of the first receiving opening140), e.g. using the lifting apparatus310.

In an example, the lifting apparatus310is a crane-type apparatus. In an example, the lifting apparatus310includes a crane hook.

According to an example, supporting a weight of the mechanical damper apparatus110(or de-mounting the mechanical damper apparatus110) includes catching a hook element of the mechanical damper apparatus110with a crane hook of the lifting apparatus310.

In an example, the hook element of the mechanical damper apparatus110has a dimension (e.g. width, length, and/or a dimension in a direction extending away from the mechanical damper apparatus110) of at least 50% or at least 100% of a diameter or width of the mechanical damper apparatus110. In an example, the hook element of the mechanical damper apparatus110is configured to be large enough to be caught by a crane hook or an eye hook or a lifting hook or an open hook or an un-closed hook. Accordingly, a remotely controlled hook device320can be neglected/unnecessary during de-mounting/disassembly.

In an example, de-mounting (or disassembly) of the mechanical damper apparatus110includes supporting a weight of (or lifting) the mechanical damper apparatus110while tensioning the first rope-type guide element130. Accordingly, the protruding portion of the first connector150may be guided out of the first receiving opening140in a simple manner, e.g. without any particular further equipment or method.

In an example, de-mounting (or disassembly) of the mechanical damper apparatus110includes supporting a weight of (or lifting) the mechanical damper apparatus110while tensioning the first rope-type guide element130. Accordingly, the protruding portion of the third connector450may be guided out of the receiving portion of the fourth connector460in a simple manner, e.g. without any particular further equipment or method.

According to an example, de-mounting the mechanical damper apparatus110may be performed directly (or immediately) prior to, or directly (or immediately) following, the assembly or re-assembly of the nacelle and/or rotor blades of the wind turbine.

Accordingly, the aspects, embodiments, and examples described herein improves the installing of a mechanical damper apparatus to a tower of a wind turbine when the tower is in an erect state. In particular, the methods described herein provide a durable, long-term solution.

The present written description uses embodiments and examples to provide enabling disclosure. The scope of the present invention is defined by the claims.