MX2007011244A - Wind turbine nacelle with integral service crane for accessing turbine components - Google Patents

Abstract

A service crane for a wind turbine comprising a main crane beam (128) having a track (154) that accommodates a trolley (156) . A hinge (144) is provided at a pivot point (148) near a proximate end of the main beam (128), such that an aft portion of the main beam (128) extends beyond the pivot point (148) to the exterior of the turbine. A distal end of the main beam (128) rests upon a forward beam. A lateral motion actuator (134) moves the main beam (128) back and forth along the forward beam. The trolley (156) runs back and forth along the main beam (128) . A turbine component is attached to a hook lowered by cable from the trolley (156) . The trolley (156) with the component on the hook is moved to the aft portion of the main beam (128), which extends beyond the turbine. The hook is lowered to the ground so that the component can be serviced or replaced.

Description

WIND TURBINE BOAT WITH SERVICE CRANE INTEGRAL FOR ACCESS TO THE COMPONENTS OF THE TURBINE Field of the Invention This invention relates to wind turbines housed inside a nacelle, on top of a tall tower and, more particularly, to an integrated service crane to provide access to the turbine components on top of tall towers.

Description of the Prior Art The cost of electricity, generated by the wind, has been reduced due to technological innovations and economies of scale. The average size of the turbine is now approximately 1.5 MW, with rotor diameters ranging from 70 to 85 m. This class of turbines has on average a 50-tonne weight of the nacelle (generators, gearbox and nacelle housing) and a rotor weight of approximately 35 tons. To improve the economics of wind turbines, manufacturers have designed higher towers to take advantage of higher wind energy and higher levels above the ground. Manufacturers are increasingly depending on tower designs of 80 to 100 m, rather than the shorter towers previously used. The cost of decreasing and raising these weights from / to the tops of the towers based on high areas for service can be prohibitive, mainly due to the reach of conventional cranes, which require a crane capacity much greater than the actual weight that rises. This is due to the bending moment which results from the reach of conventional cranes. Patent US 6,955,025 describes a method of raising a wind turbine tower, in which the nacelle and generators of the turbine housed in this nacelle are in the upper part of the tower. It is possible to use the method described there to lower the tower and nacelle to replace this nacelle and turbine. However, routine maintenance or replacement of only one component, such as a generator, is not cost effective to lower the entire gondola. Only the defective component needs to be lowered. In the conventional method of the prior art, the use of a typical floor-level crane, an impulse train or its component is raised above and on top of a nacelle, located at the top of a tall tower. This impulse train or component is then lowered through a hatch door in the upper part of the nacelle. The reverse procedure is used to remove and download components for the service. An elevation of a 50-ton drive train requires a crane of 400 to 600 tons. This greater capacity is required due to the high bending moment associated with the reach of the crane. Currently, wind turbines require that a crane or special device be brought to the site of the wind turbine for access to the components through the removal of the upper part of the nacelle, in order to remove the components outside. from the top of the nacelle and lower them to the ground for repair or replacement. This adds a substantial cost to repair and component replacement activity, which leads to an increase in the cost of energy. It is convenient to provide an apparatus that facilitates this repair and replacement of the components of the wind turbine and thus reduce the costs of such repair and replacement.

SUMMARY OF THE INVENTION Briefly, the invention relates to a service crane of a wind turbine, to lift the heavy components of the turbine on top of a very high tower (70 to 100 m).

The service crane for a wind turbine comprises a mobile main crane beam, having a track for guiding a trolley, a first frame comprising a hinge at a pivot point, in which the beam of the crane is connected to the hinge, so that a portion of the crane beam extends beyond the pivot point, a stationary beam that connects to a distal end of the crane beam, so that this crane beam can move laterally along the stationary beam. According to one embodiment of the present invention, the service crane comprises a main crane beam, which has a track on which a trolley can go. A hinge is provided at a pivot point near a proximal end of the main beam, so that the rear portion of the beam extends beyond the pivot point to the outside of the turbine, the hinge is supported by a rear frame , attached to the floor of the car and connected to the main beam. A distal end of the main beam is supported on a front beam, which is supported by a front frame attached to the floor of the nacelle. An impeller of lateral movement, operatively connected to the main beam, moves this main beam back and forth along said main beam.

In operation, the trolley moves into the turbine, where a turbine component is attached to a hook, which is lowered by the cable from the trolley. This trolley, with the component on the hook, moves to the rear position of the main beam, which extends beyond the turbine. The hook is then lowered to the ground so that the component can be serviced or replaced. The on-board service crane comprises a service crane structure, which supports the housing and provides access to the housing to the outside of the nacelle, from the service level, through the accommodation door. The service crane enables the supply of the service to the upper end of a wind turbine tower, without the need to move a large crane. The capacity of the service crane is comparable to the high weights. The invention has the advantage that, because the crane is an integral part of the nacelle, it avoids the need to take the crane at ground level or a special apparatus to the site of the wind turbine, for access to the components, to Through the removal of the upper part of the nacelle, in order to remove the components and lower them to the floor for repair or replacement.

The invention has the advantage of decreasing the cost of clean energy, reducing maintenance and repair costs of wind turbines.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in detail with reference to the drawings, in which: Figure 1 is a perspective view of a crane inside a nacelle, to elevate the components of the turbine to the nacelle, located in the top of a tower; Figure 2 is a front elevation view of the nacelle, shown in Figure 1; Figure 3 is a side view of a car door, shown in Figure 1; and Figure 4 is a perspective drawing, showing the bed of the nacelle with the crane inside this nacelle.

DESCRIPTION OF THE PREFERRED MODALITIES Referring to Figure 1, which is a perspective view of a crane inside a nacelle, to elevate the turbine components to the nacelle, located at the top of a tower. An edge-mounted service crane with a capacity of 2 tons is installed in the rear of the nacelle. A hinged or lower roller door, on the back of the nacelle, allows components to be lowered and service tools and other materials raised from the ground. The crane allows the service of the brakes, deviation motors, generators, pinion cartridges of the gearbox and other components. Avoiding the need to use a crane for small service, the use of this on-board service crane is expected to produce a positive benefit to maintenance costs both scheduled and unscheduled. Referring to Figure 2, which is a front elevation view of the nacelle shown in Figure 1, and Figure 3, which is a side view of the nacelle door shown in Figure 1. The structure of the crane of Service support the side and top surfaces of the nacelle. There is access to the components of the wind turbine from the service level of the nacelle to the outside, through the rear door, shown in Figure 1 and on the right side of the drawing of Figure 3. The nacelle is partially illustrated in Figure 4 and is of a conventional design in the form of a bath tub. The nacelle houses a turbine having four generators 100, 102, 104 and 106, connected through a gearbox 108 to a main arrow 110, held in place by a main bearing 112, attached to the floor of the bath tub 114 of the nacelle. The main arrow is connected to a rotor hub 116, which conventionally has three rotor blades 118, 10 and 122, which are rotated by the wind. These rotor blades rotate the main arrow 110, which moves the gears in the gearbox 108. The gears rotate the generators, which produce electricity from the wind energy. The nacelle service crane includes a forward, stationary, curved I-beam frame 124 attached to the main bearing 112 and a movable, linear I-beam crane rail 128 that abuts a distal end 130 on the front frame 124 by means of four rollers 134, 134, 138, 140. One or more of the rollers is connected to a laterally moving main beam driver, such as a servomotor, which when operated causes the main beam to move in one direction side. Alternatively, a rope and pulley side movement impeller can achieve lateral movement. The proximal end 142 of the crane rail 128 is attached by means of a hinge 144 to a stationary rear frame 146, mounted on the floor of the bath tub 114 of the nacelle. The crane rail can rotate about the hinge axis 148 within the outer limits 150, 152, adjusted by the length of the front frame in which the distal end of the crane rail is supported. A lower portion 154 of the I-beam of the crane rail acts as a top mono-rail, on which trolley 156 goes. This trolley is suspended from the upper crane rail by means of four wheels 158, 160, 162 and 164, which assemble the crane on the beam in I of the rail. One or more rollers are connected to a longitudinally moving trolley impeller, such as a servomotor, which, when actuated, causes the trolley to move in a longitudinal direction along the crane rail. Alternatively, an impeller of longitudinal movement of cable and pulley can achieve longitudinal movement. The trolley has a hook 166, which can be raised and lowered by a cable 168 and winch (not shown). The hook can be attached to a component, such as one of the generators, for the purpose of transporting it to the proximal end of the crane rail, which is outside the nacelle. Because the crane rail can be moved around the pivot point 148, any of the generators is accessible to the hook by moving the crane rail laterally. A fuselage 170 is mounted on the proximal end 142 of the crane rail. This fuselage is configured to reduce drag, which can induce deviations. The winch mechanism is housed within the fuselage, with the additional ability to operate the crane rail driver to move this crane rail back and forth on the front frame 124 and operate the trolley driver to move this trolley back and forth to along the crane rail 128. The trolley is free to move past the rear frame 146 to the outside of the nacelle and into the fuselage 170, which is also outside the nacelle. Once out of the nacelle, the hook 166 with the attached component can be lowered by the cable at floor level for service to the components. The nacelle is adapted with a hinged or revolving door 171, which is operated by a mechanism within the fuselage to move the door out of the way and allow the trolley to exit the rear part of the nacelle. The FAA chuck pivots forward on a movable arm 174 to allow access. The structural support frame of the crane, the frame 124 of the forward, stationary, curved beam I, the stationary rear frame 147, mounted to the bath tub 114 of the nacelle, also serve as structural supports for the sides and the upper part of the turbine housing of the nacelle. The sides and the upper part of the nacelle are not shown in Figure 4. The crane structure allows the horizontal delivery of the components to the outside of the nacelle, through the rear door 171, from which they are lowered to the level from the floor. The conventional design requires the removal of the upper part of the nacelle and the extraction of the component is done vertically. The lateral movement of the main beam 128 of the crane and the movement 156 of the trolley of the crane, along the beam, allow a wide access interval of the turbine component. Since the service crane is an integral part of the structure of the wind turbine, it is always available for maintenance or replacement work of the components. The use of the existing structure allows the elevation of the crane to be cost effective, reliable and classified to the required workload. This helps reduce the cost of clean energy, thus reducing the costs of maintenance and repair of wind turbines. While the invention has been particularly shown and described with reference to its preferred embodiments, it will be understood by those skilled in the art that the foregoing and other changes may be made in detail and form, without departing from the scope of the invention.

Claims (1)

1. CLAIMS A service crane for a wind turbine, this crane comprises: a main beam, mobile crane, which has a track for the guidance of a trolley; a first frame, comprising a hinge at a pivot point, in which the crane beam is connected to the hinge so that a portion of the crane beam extends beyond the pivot point; a stationary beam, which is connected to a distal end of the crane beam, so that this crane beam can move laterally along the stationary beam. The service crane of claim 1, wherein the track is designed as a top rail on which this trolley can go. The service crane of claim 1 or 2, wherein the first frame supports a lateral structure of the nacelle and is attached to the floor of the nacelle. The service crane of any of claims 1 to 3, wherein the crane beam is supported on the stationary beam. The service crane of any of claims 1 to 4, wherein the stationary beam is supported by a second frame. The service crane of claim 5, wherein said second frame comprises the main bearing of the nacelle. The service crane of any of claims 1 to 6, wherein a laterally moving driver is operatively connected to the crane beam, to move this crane beam laterally along the stationary beam. The service crane of any of claims 1 to 7, wherein the stationary beam is curved. The service crane of any one of claims 1 to 8, wherein a fuselage is mounted to a proximal end of the crane beam, said fuselage being configured to thereby reduce drag. The service crane of any of claims 1 to 9, wherein the longitudinal movement driver is operatively connected to the trolley.