WO2018010744A1

WO2018010744A1 - A power tool system, a method for controlling operation of a power tool system and use of a power tool system

Info

Publication number: WO2018010744A1
Application number: PCT/DK2016/050248
Authority: WO
Inventors: Lars Birkkjær Nielsen
Original assignee: Your Global Solution Aps
Priority date: 2016-07-14
Filing date: 2016-07-14
Publication date: 2018-01-18

Abstract

Disclosed is a power tool system (1) for a wind turbine (2) in a wind turbine site. The system (1) comprises at least one power tool (3) and log-in means (4) arranged to determine unique log-in information (6) of an operator (5) of the power tool (3). The system (1) further comprises position determining means (21) arranged to determine or at least estimate a position (36) of the power tool (3) and communication means (7) for communicating with a database (8) comprising operator data (9) and position data (10) of one or more wind turbines (2) or wind turbine components. The system (1) also comprises control means (11) arranged to enable operation of the power tool (3) in response to a validation of the log-in information (6) in relation to the operator data (9) in the database (8) and/or in response to a validation of the position (36) in relation to the position data (10) in the database (8). A method for controlling operation of a power tool system (1) for a wind turbine (2) in a wind turbine site and use of a power tool system (1) is also disclosed.

Description

A POWER TOOL SYSTEM, A METHOD FOR CONTROLLING OPERATION OF A POWER TOOL SYSTEM AND USE OF A POWER TOOL SYSTEM

Field of the invention

The invention relates to a power tool system for a wind turbine in a wind turbine site. The invention also relates to a method for controlling operation of a power tool system for a wind turbine in a wind turbine site and use of a power tool system.

Background of the invention

Over the last decades wind turbines have become bigger and bigger both in capacity and in size. And erecting, doing maintenance or servicing them has therefore become a more specialized and potentially dangerous job. E.g. the bolt connections in the tower, between tower and nacelle, between blades and hub and many other places in the wind turbine requires much torque both during assembly and subsequent maintenance, and for that purpose very powerful power tools have been developed. Thus, omissions, mistakes, misuse or misunderstandings during assembly or subsequent service can have catastrophic results.

From US 2014/040325 Al it is therefore known that a user performing maintenance work on an energy conversion installation can store documentation data from maintenance and repair in a maintenance database by means of a mobile user appliance so that maintenance and repair work may be documented.

From US 2016/080902 it is also known to use a portable communication device to identify a specific wind turbine based on a comparison of position coordinates of the wind turbine with position coordinates of the portable communication device by means of a positioning system to automatically serve service personnel with wind turbine specific service information. However, faults and mistakes during erection and service and misuse of equipment is still possible.

It is therefore an obj ect of the present invention to provide for a safer power tool system for a wind turbine.

The invention

The invention provides for a power tool system for a wind turbine in a wind turbine site. The system comprises at least one power tool and log-in means arranged to determine unique log-in information of an operator of the power tool. The system further comprises position determining means arranged to determine or at least estimate a position of the power tool and communication means for communicating with a database comprising operator data and position data of one or more wind turbines or wind turbine components. The system also comprises control means arranged to enable operation of the power tool in response to a validation of the log-in information in relation to the operator data in the database and/or in response to a validation of the position in relation to the position data in the database.

Since the power tools used in wind turbines usually are extremely powerful and therefore dangerous if not operated correctly, it is advantageous that the system comprises log-in means and control means so that only authorized personnel may operate the power tool. Furthermore, by providing the system with position determining means it is possible to only enable operation of the power tool if it is in a wind turbine, if it is in the correct position in a wind turbine if it is at a correct specific wind turbine or based on other position data criterions in the database. It is hereby possible to reduce the risk of operating the power tool on a wrong wind turbine, on the wrong place in a wind turbine or other.

In this context the term "power tool" should be understood as any kind of tool that is actuated by an additional power source and mechanism other than the solely manual labour used with hand tools. The most common types of power tools are driven by electric motors, hydraulic power, internal combustion engines or compressed air but other power sourced can be used. Such power tools include any kind of wrench, bolt tightening tool, drill, saw, hammer, lift, crane, robot, jib, articulated lift arm, winch, pressing tool, pulling tool or other or any combination thereof. It should be noticed that the term "power tool" in this context relates to both stationary and portable power tools.

In this context the term "log-in means" should be understood as any kind of log-in interface suitable for determining a unique identity of an operator, such as any kind of fingerprint scanner, iris scanner, code input interface, wireless tag reader, QR or barcode scanner, magnetic stripe card reader or other or any combination thereof.

In this context the term "position determining means" should be understood as any kind of position determining device suitable for determining or estimate a position of a power tool, such as any kind of GPS tracker, device for multilateration (such as triangulation) of phone/radio signals, Bluetooth tracker, RFID, interface for inputting unique location data, scanner for scanning unique location data or other or any combination thereof.

In this context the term "communication means" should be understood as any kind of communicating device suitable for communicating with a database comprising operator data and position data, such as any kind of phone device, WIFI device, wire conductor or other or any combination thereof.

In this context the term "control means" should be understood as any kind of controller suitable for enabling operation of a power tool in response to a validation process, such as any kind of PC, programmable logic controller (PLC), logic circuits or other or any combination thereof. In an aspect of the invention, the operator data in the database comprises information on the operator's credentials.

It is advantageous to make the database comprise information on the operator's credentials in that the database hereby can be used to authorising use of new power tools without having to amend the database. I.e. if a certain new power tool requires course X attendance to be operated, all users having attended course X will be authorised to use it. This is advantageous over e.g. appointing different levels of clearance to the different operators in that level X clearance typically is dependent on many other factors than course X and personnel actually having passed course X could then be excluded from operating this specific power tool.

In an aspect of the invention, the credentials include proof of experience, certificates, diplomas or credits. Hereby is achieved an advantageous embodiment of the invention.

In an aspect of the invention, the position data in the database comprises information on a substantially exact or an at least partly estimated position of the one or more wind turbines or wind turbine components. It is advantageous that the position data in the database comprises information on the location of the wind turbines in that e.g. in a wind farm, the risk of entering a wrong wind turbine by mistake is imminent and by including position data it is possible to ensure that the power tool may only operate when located at or in the correct wind turbine or wind turbine component.

E.g. the tower could be at least partly preassembled at a location close to the actual erection site, and it is therefore advantageous that information on the location of also wind turbine components is included in the database. In an aspect of the invention, the power tool system further comprises sensor means for detecting operational data of the power tool.

It is advantageous to make the power tool system comprise sensor means for detecting operational data of the power tool in that these data can be used for documentation purposes, they can be used as an extra security level e.g. if the sensed data does not comply with expected data, they can further protect against misuse - e.g. by further detection of operator, by monitoring correct use or other. In this context the term "sensor means" should be understood as any kind of sensor suitable for detecting operational data of the power tool - i.e. the sensor means could be any kind of pressure gauge, thermometer, proximity sensor or other or any combination thereof. In an aspect of the invention, the power tool system further comprises sensor data transferring means for transferring the operational data from the sensor means to logging means of the power tool system.

Providing the power tool system with sensor data transferring means for transferring the operational data from the sensor means to logging means is advantageous in that the operation of the power tool hereby can be documented and later accessed, controlled, approved or other and/or maintenance of the power tool can be effectuated on the bases of the logged data. In this context the term "sensor data transferring means" should be understood as any kind of sensor data transferring device for suitable for transferring the operational data from the sensor means to logging means of the power tool system, such as any kind of phone device, Bluetooth device, WIFI device, light or electrical conductor or other or any combination thereof. In an aspect of the invention, the sensor data transferring means comprises wireless data transferring means.

The power tool is usually mobile and will have to be moved around inside the wind turbine and between different wind turbines. It is therefore simpler and more efficient to transfer the sensor data wirelessly.

In this context the term "wireless data transferring means" should be understood as any kind of wireless data transferring device for suitable for transferring the operational data from the sensor means to logging means of the power tool system wirelessly, such as any kind of phone device, Bluetooth device, WIFI device, or other or any combination thereof.

In an aspect of the invention, the logging means is logging means according to any of the logging means described in the following. Hereby is achieved an advantageous embodiment of the invention.

In an aspect of the invention, the sensor means is arranged to detect tensioning of a bolt connection.

Over-tensioning bolt connections can lead to catastrophic failures during the tensioning process which can be dangerous to the operator, and both under-tensioning and over-tensioning can lead to malfunction of the bolt-connection. It is therefore advantageous that the tensioning of the bolt connection can be monitored by means of the sensor means.

In an aspect of the invention, the sensor means comprises elongation detection means for detecting an elongation of a bolt during a bolt tensioning process. Over-elongating bolts can lead to catastrophic failures during the elongation process which can be dangerous to the operator, and both under-elongation and over- elongation can lead to malfunction of the bolt-connection. It is therefore advantageous that the elongation of the bolt can be monitored by means of the sensor means.

In an aspect of the invention, the sensor means comprises stretching force detecting means for detecting a bolt stretching force during a bolt tensioning process.

Use of excessive force during a bolt tensioning process can lead to catastrophic failures during the tensioning process which can be dangerous to the operator, and both using too little force and too much force can lead to malfunction of the bolt-connection. It is therefore advantageous that the applied force can be monitored by means of the sensor means. In an aspect of the invention, the sensor means comprises tightening force detecting means for detecting a tightening force during a nut tightening process.

Once the bolt has been stretched sufficiently the nut will have to be tightened to maintain the tension level. However, use of excessive force during the nut tightening process can lead to catastrophic failures during the tightening process which can be dangerous to the operator, and both using too little force and too much force can lead to malfunction of the bolt-connection. It is therefore advantageous that the applied force can be monitored by means of the sensor means. In an aspect of the invention, the position determining means comprises means for multilateration of radio signals.

Multilateration of radio signals - such as mobile phone signals - is not particularly precise and in certain embodiment it can be a bit complex. But the great advantageous is that it most often will also work even e.g. inside a steel wind turbine tower. So when a little imprecision is accepted, multilateration of radio signals is advantageous for position determining means in relation with power tool systems for use in wind turbines. In an aspect of the invention, the position determining means comprises GPS means.

The GPS system is global and it is very precise and GPS positioning is available even on the cheapest smart phone. It is therefore advantageous to determine the position of the power tool by means of GPS means such as a GPS receiver, a GPS sender or a similar GPS (Global Positioning Signal) device.

In an aspect of the invention, the position determining means comprises Wi-Fi-based positioning means. Wi-Fi systems usually has a limited ranged and if e.g. every wind turbine in a wind farm is equipped with its own wireless Wi-Fi router the position of the power tool could efficiently be detected or estimated on the basis of e.g. a trilateration of the Wi- Fi signals. It should be noted that Wi-Fi (or WiFi) is a technology that allows electronic devices to connect to a wireless LAN (WLAN) network, mainly using the 2.4 gigahertz (12 cm) UHF and 5 gigahertz (6 cm) SUF ISM radio bands. A WLAN is usually password protected, but may be open, which allows any device within its range to access the resources of the WLAN network.

In an aspect of the invention, the position determining means comprises Bluetooth tracking means.

Bluetooth tracking is a cheap and efficient way of tracking the position of the power tool. In an aspect of the invention, the position determining means comprises passive or active RFID tags.

Providing the wind turbine with Radio-frequency identification (RFID) reader and then providing the power tool with a RFID tag (or vice versa) is a simple and inexpensive way of providing position determining means.

In an aspect of the invention, the power tool system comprises mobile communication means for communicating with a mobile unit of the operator.

It is advantageous to enable the power tool system to communicate with a mobile unit - such as a smartphone - of the operator, in that the mobile unit hereby can form part of the power tool system e.g. by making the log-in means comprise the fingerprint reader already present on the smartphone or other means for unique identification already present in the smartphone. Or the mobile unit could be used for scanning QR or barcodes on the power tool, on the wind turbine, on the specific location or other to enable that the mobile unit is at least partly used as position determining means. Or work data regarding the present service task or similar could be communicated to the operator through the mobile device.

In an aspect of the invention, the mobile unit comprises a mobile phone.

Mobile phones such as smart phones are usually very versatile and practicable and it is therefore advantageous if the power tool system includes a mobile phone.

In an aspect of the invention, the power tool system further comprises logging means.

Providing the power tool system with logging means is advantageous in that it hereby is possible to log information on e.g. operator, location, task, operation or other and subsequent access this information to do statistic, to plan maintenance, to provide documentation or other.

In this aspect the term "logging means" should be understood as any kind logger or logging device suitable for logging data in or from a power tool system. Such logging means may comprise any kind of hard drive, RAM, memory stick, database or any other kind of medium or device suitable for recording and storing information and data.

In an aspect of the invention, the logging means is arranged for logging operational data of the power tool.

The power tool is heavily strained during operation and certain parts may have to be replaced at fixed intervals and/or service will have to be performed after certain work cycles. It is therefore advantageous to make the logging means log operational data of the power tool. Furthermore, by logging operational data of the power tool it can also subsequently be documented that e.g. a certain bolt was tightened correctly and at the right time.

In an aspect of the invention, the logging means is arranged for logging operational data of the operator.

By logging operational data of the operator it is possible to track the operator with the most experience in a certain task, it is possible to track the development of the operator, it is possible make statistical material on the operator and other.

In an aspect of the invention, the logging means is arranged for logging data from the position determining means. By logging position data of the power tool it is always possible to find the power tool or it is at least possible to track its last recorded position, it is possible to detect use of the power tool at unauthorized locations and other. In an aspect of the invention, the log-in means comprises a user interface.

Providing the power tool with a user interface is advantageous in that it hereby is possible to present information to the operator. And using the user interface as log-in means is advantageous in that it hereby is possible to log in by means of a unique operator specific code or by other features enabled by the interface.

In an aspect of the invention, the log-in means comprises a scanner.

A scanner enables that the operator can log in by means of a personal QR code or similar codes and the scanner further enables that outer parts may be scanned such as replacement parts, information plates in or on the wind turbine or other, location codes, or other.

In an aspect of the invention, the log-in means comprises a card reader.

A magnetic card can hold relatively many information on the operator and the magnetic card technology is well-proven and therefore advantageous as log-in means for a power tool system. In an aspect of the invention, the communication means comprises wireless communication means.

To enable easy mobility of the power tool it is advantageous to provide the power tool system with wireless communication means such as a wireless communicator. In an aspect of the invention, the power tool comprises a bolt tensioning tool.

Particularly the high power bolt tensioning tools used in wind turbines can be dangerous to use if the operator is not properly trained. And the consequences of a failing bolt connection in a wind turbine can have catastrophic consequences. It is therefore particularly advantageous to use the present power tool system in relation with bolt tensioning tools.

In an aspect of the invention, the power tool is a stud tensioning unit for tensioning stud bolts in a tower of the wind turbine.

Stud tensioning involves elongating a very large stud bolt which accordingly requires very high tensioning loads performed by a tool that can be handled manually by an operator. If this high pressure tool fails it can be very dangerous to the operator. It is therefore particularly advantageous to use the present power tool system in relation with a stud tensioning unit.

In an aspect of the invention, the stud tensioning unit comprises hydraulic extending means arranged to extend the stud bolt and a hydraulic station arranged to generate a hydraulic pressure driving the hydraulic extending means.

Hereby is achieved an advantageous embodiment of the invention.

In an aspect of the invention, the control means is arranged to only enable operation of the power tool if the log-in information is validated in relation to the operator data in the database and if the position is validated in relation to the position data in the database. It is advantageous if both the operator and the location is validated before use of the power tool is enabled in that this ensures that only the right person can operate the power tool at only the right location. The invention further provides for a method for controlling operation of a power tool system for a wind turbine in a wind turbine site. The method comprises the steps of:

• determining unique log-in information of an operator of the power tool, and · enabling operation of the power tool in response to a validation of the log-in information in relation to operator data in a database.

By only enabling operation of the power tool in response to a validation process it is ensured that only the right operator is allowed to use the power tool which is advantageous in that the risk of misuse and faults is reduced.

In an aspect of the invention, the method further comprises the step of determining or at least estimating a position of the power tool. It is advantageous to determine the location of the power tool before operation is enabled in that it hereby can be prevented that the tool is used in a wrong location, the location of the toll can be tracked or the location of the tool during operation can be documented subsequently. In an aspect of the invention, the method further comprises the step of communicating the position of the power tool to control means enabling the operation, wherein the control means has access to a database comprising position data of one or more wind turbines or wind turbine components. Hereby is achieved an advantageous embodiment of the invention. In an aspect of the invention, the method further comprises the step of enabling operation of the power tool in response to a validation of the position of the power tool in relation to the position data in the database.

It is advantageous to only enable operation of the power tool if the power tool is at the right location.

In an aspect of the invention, work data is communicated to the operator once the operation is enabled.

If a correct location is a precondition for enabling use of the power tool the exact location will obviously have to be communicated to the operator before the validation process. However, if operation is not enabled, the service task or similar cannot be performed anyway. Thus, it is advantageous to only communicate basic info - like work location - to the operator before validation and then only provide the actual work data after operation has been enabled.

It should be noted that in this context the term "work data" could be any kind of data relating to a specific task - such as the bolt tensioning level, bolt tensioning sequence, elongation level, location, instructions or other.

In an aspect of the invention, the work data is communicated to the operator by means of the power tool.

The work data will always have to be used at the power tool and it is therefore advantageous to communicated to these data to operator by means of the power tool - e.g. by means of a display and/or a loudspeaker on the power tool. In an aspect of the invention, the work data is communicated to the operator by means of a mobile unit of the operator.

Communicating the work data to the operator by means of a mobile unit - such as a mobile phone - is advantageous in that a mobile unit can be accessed at places where other types of more stationary means would be difficult to fit, and it can easily be moved around.

In an aspect of the invention, the work data comprises information regarding substantially exact work location.

Before operation and/or before validation the operator could be directed to a specific wind turbine but wind turbines are very large nowadays and it is therefore advantageous to provide the exact work location once operation has been enabled.

In an aspect of the invention, the work data comprises information regarding a tensioning sequence of a bolt array.

Tensioning levels and other may be automated and therefore out of the operator's control. But a main idea behind a power tool is that it at least to some degree is mobile and the operator will thus have to move the tool around. It is therefore advantageous to provide the operator with information on the tensioning sequence of a bolt array.

In an aspect of the invention, the work data comprises information regarding operation of the power tool.

It is advantageous to provide the operator with information regarding operation of the power tool - such as a user manual, information on wear or other - in that it enables the operator to more efficiently use the power tool. In an aspect of the invention, the work data comprises information regarding status of the power tool.

Hereby is achieved an advantageous embodiment of the invention.

In an aspect of the invention, the operation of the power tool is disabled again a predefined time period after operation of the power tool has stopped.

In an aspect of the invention, the operation of the power tool is disabled again if the power tool is moved a predefined distance away from a position at which the operation was enabled.

In an aspect of the invention, the operation of the power tool is disabled again if the operator moves a predefined distance away from the power tool.

The main reason for validating a used before operation of the power tool is enabled, is to ensure that only authorized personnel operates the power tool. It is therefore advantageous that the operation of the power tool is disabled again in response to one or more of the above scenarios.

In an aspect of the invention, the method also comprises the step of tracking a position of the operator.

By tracking the operator, it can be ensured that the operator does not leave an enabled power tool unattended, it can be tracked if the operator moves correctly in relation to the work task - e.g. tightening bolts in a bolt array in a particular sequence - and similar.

In an aspect of the invention, the method also comprises the step of tracking a position of the power tool . By tracking the power tool, it can be ensured that an operating power tool is not moved to an unauthorized location, that the tool is moved correctly in relation to tightening bolts in a bolt array in a particular sequence and similar In an aspect of the invention, the log-in information and the position of the power tool is logged.

By logging the log-in information it is possible to subsequently trace e.g. who performed service on a particular wind turbine joint - e.g. supplemented by information on when and with what power tool - and by logging the position it can subsequently be proven that the service was performed on the correct joint.

In an aspect of the invention, the log-in information and the position of the power tool is logged together with operational data of the power tool.

The invention also relates to use of a power tool system according to any of the previously described power tool systems for tightening bolts in a wind turbine in a wind farm. Bolts arranged to assemble tower sections, to connect blades to the hub, to connect the nacelle to the tower or other are very large and it therefore take a substantial force to tighten these bolt. Thus, if anything goes wrong this process can be very dangerous. It is therefore advantageous that only operators having been authorized to operate such potentially dangerous tools can enable operation of the power tool. Furthermore, in wind farms the risk of mixing up wind turbines is increased and the risk of servicing a wrong wind turbine is thus increased. It is therefore particularly advantageous to use a power tool system according to the present invention ion relation with wind farms. Figures

The invention will be described in the following with reference to the figures in which fig. 1. illustrates a wind turbine as known in the art, as seen in perspective, fig. 2 illustrates a simplified representation of a power tool system, as seen from the front, fig. 3 illustrates a cross section through a stretching device mounted on a stud bolt, as seen from the front, fig. 4 illustrates a power tool system in use in a wind farm, fig. 5 illustrates an embodiment of a structure of a power tool system, and fig. 6 illustrates a diagram of an embodiment of the operation of a power tool system.

Detailed description

Fig. 1 illustrates an embodiment of a modern wind turbine 2 as known in the art comprising a tower 26 and a wind turbine nacelle 30 positioned on top of the tower 2. The wind turbine rotor 31, comprising three wind turbine blades 32 mounted on a hub 33, is connected to the nacelle 30 through a low speed shaft which extends out of the front of the nacelle 30.

Fig. 2 illustrates a simplified representation of a power tool system 1, as seen from the front. In this embodiment of the invention the power tool 3 is a bolt tensioning tool comprising a stretching device 34 which the operator moves around between bolts (not shown) manually. In this embodiment the stretching device 34 is hydraulically driven by a hydraulic station 28 comprising a hydraulic pump capable of generating sufficient hydraulic pressure to drive operation of the stretching device 34. The hydraulic station 28 is typically quite heavy and is in this embodiment equipped with wheels enabling that the hydraulic station 28 may more easily be moved around between different work locations. The hydraulic pressure is in this embodiment transferred to the stretching device 34 by means of a hose 40 and in one embodiment all data communication between the stretching device 34 and the hydraulic station 28 could take place through a conductor extending along or incorporated in the hose 40. However, in this embodiment the stretching device 34 and the hydraulic station 28 is provided with sensor data transferring means 14 - such as a wireless communicator - enabling wireless communication between the stretching device 34 and the hydraulic station 28.

In this embodiment the hydraulic station 28 is also provided with position determining means 21 in the form of a mobile phone module enabling that the roaming signal may be triangulated by means of nearby mobile phone masts so that a relatively precise position of the power tool 3 may be estimated. Such as system will typically also work inside the heavy steel structure of a wind turbine. To increase positioning precision, the mobile phone module could be supplemented (or replaced) by a GPS providing very accurate position info outside the wind turbine 2 or another type of position determining means 21.

In this embodiment the position determining means 21 is located in the hydraulic station 28 but in another embodiment the position determining means 21 could be placed in the stretching device 34 or anywhere else on the power tool 3 or the position determining means 21 could be arranged external to the power tool 3 e.g. in a mobile unit 22 of the operator. Since it is the position of the power tool 3 that is important - and not as much the position of the operator - arranging the position determining means 21 in e.g. a mobile phone of an operator would only work if it was ensured that the operator was in relatively close proximity of the power tool 3. If it e.g. was detected that the operator would be more that 3 meters from the power tool 3 (e.g. outside the range of RFID or Bluetooth tracking) operation of the power tool 3 would be disabled until the correct operator moved back near the power tool 3 or until the log-in procedure was repeated.

In this embodiment the power tool 3 is also provided with a user interface 24 in the form of a pressure sensitive display capable of presenting information to the operator. In this embodiment the interface 24 will also act as log-in means 4 in that to enable operation of the power tool 3, the operator will have to enter the correct code on the interface 24. However, in another embodiment these log-in means 4 could instead or also comprise a RFID reader capable of reading a RFID tag - e.g. in the pocket of a nearby operator -, a key, a scanner for scanning an identity card, a card reader for reading a magnetic strip identity cart or other. In this embodiment the login means 4 is located on the power tool 3 but in another embodiment the log-in means 4 could be arranged externally to and/or even remotely from the power tool 3 itself. I.e. in one embodiment the log-in means 4 could be enabled by means of a mobile unit 22 of the operator - such as by means of a dedicated application on a smartphone utilizing the identification tools already present in or on the smartphone - such as fingerprint scanners, conventional scanners, camera, code input or other.

In this embodiment the power tool 3 comprises communication means 7 for communicating with an external central database 8. In this embodiment the communication means 7 is the same mobile phone module enabling the position determining means 21 but in another embodiment the communication means 7 could instead or also comprise other means such as an electrical conductor, an optical fibre cable, Wi-Fi communication, or other long distance communication means or any combination thereof. In this embodiment the communication means 7 is integrated in the hydraulic station but particularly if the position determining means 21 and/or the log-in means 4 was enabled by means of a mobile unit 22 of the operator, the communication means 7 could also be provided by means of the mobile unit 22. In this embodiment the database 8 comprises operator data 9 in the form of a list of operators, the credentials of each operator. In this embodiment the database 8 also comprises position data regarding the physical location of wind turbines 1 or wind turbine components in a wind farm. The position data regarding the components could e.g. be continuously tracked by means of tracking devices on the components or the location could be manually entered in the database 8 or other. The database 8 could also comprise information on tasks designated to the operator and/or the power tool 3, so that operation would only be enabled if the operator was actually assigned to the specific power tool 3 and/or the power tool 3 was actually assigned to the specific task.

In this embodiment the database 8 also comprises work data 29 for use in relation with the power tools 3 or control means 11 accessing the database 8. This could be assembly manuals, bolt tensioning schemes, maintenance manuals or schedules or many other things regarding the wind turbine 1, the wind turbine components, the power tool 3 or other.

In this embodiment the operator data 9, the position data 10 and the work data 29 are all stored in the same database 8 placed in a single central location far away from the wind turbine site. However, in another embodiment one or more of the operator data 9, the position data 10 and the work data 29 could be stored elsewhere - i.e. the database 8 does not have to be arranged in a single location but could be physically spread out over several locations e.g. under the control of different parties - such as a subcontractor, the site manager, the wind turbine manufacturing company or other. In another embodiment of the invention the database 8 or at least parts of the database 8 could be arranged in the power tool 3 or in the mobile unit 22 of the operator. In this embodiment the power tool system 1 also comprises control means 11 in the form of a PC arranged at the same physical location as the database 8. The control means 11 checks that data 36 from the position determining means 21 fulfills the position data criteria 10 in the database 8 and/or that the log-in information 6 from the log-in means 4 fulfills the operator data criteria 9 present in the database 8 and if everything is in order the control means 11 enables operation of the power tool 3 by e.g. sending a signal triggering that the hydraulic pump of the power tool 3 may be started. However, in another embodiment the control means 11 could be formed more integrally with the database 8 and/or the control means 11 or parts of the control means 11 could be arranged in or at the power tool 3 or in a mobile unit 22 of the operator e.g. in the form of a dedicated application being executed on the mobile unit 22.

Thus, for the power tool 3 to communicate directly with the mobile unit 22 of the operator, the power tool 3 is in this embodiment also provided with mobile unit communication means 23 which in this embodiment is a Bluetooth communication device but in another embodiment the mobile unit communication means 23 could comprise a Wi-Fi communication device, a SEVI card allowing communication on the normal mobile network or similar communication devices. However, in an embodiment the mobile unit 22 of the operator could also only communicate with the power tool 3 via the database 8, the control means 11 or other.

In this embodiment the hydraulic station 28 is further provided with stretching force detecting means 19 and tightening force detecting means 20 in the form of the same pressure gauge measuring the hydraulic pressure in the hose 40. However, in another embodiment the detection means 19, 20 could be formed as individual gauges. Fig. 3 illustrates a cross section through a stretching device 34 mounted on a stud bolt 18, as seen from the front.

In this embodiment the power tool 3 is a bolt tensioning tool 25 particularly suited for tensioning stud bolts 18. A Stud Bolt 18 is a threaded rod with two heavy hexagon nuts 36 as compared to a traditional Hex Bolt that has a fixed head with one nut.

In this embodiment the stud bolt 18 is tensioned by means of a stretching device 34 which is mounted on the stud bolt 18 so that hydraulic extending means 27 - such as a hydraulic actuator - of the device 34 engages the thread of the bolt 18. The bolt 18 is then stretched by the hydraulic pressure generated in the hydraulic station 28 seen in fig. 2 where after the upper nut 35 is tightened - either manually or by the stretching device 34 - so that the tensioning level of the bolt 18 is maintained once the stretching device 34 is released from the stud bolt 18. After this procedure the stretching device is typically moved to the next stud bolt 18 manually by an operator.

In this embodiment the stud bolt 18 is part of a circular bolt array connecting one tower section to another tower section. However, in another embodiment the stud bolt 18 could connect other parts of the wind turbine 1 or it could connect parts to be used in the wind turbine 1.

In this embodiment the stretching device 34 is provided with sensor means 12 for detecting operational data 6 of the stretching device 34. I.e. in this embodiment the stretching device 34 is provided with elongation detection means 17 in the form of an elongation sensor which in this case is a proximity sensor but in another embodiment the elongation detection means 17 could instead or also comprise an ultrasound sensor, a radar, a light sensor or other. The elongation detection means 17 is arranged to detect how much the bolt 18 is being elongated when being stretched by the hydraulic extending means 27 of the stretching device 34. In this embodiment the stretching device 34 also comprises stretching force detecting means 19 in the form of a pressure gauge arranged to detect the hydraulic pressure during the stretching process. When the area the hydraulic fluid is acting on the hydraulic extending means 27 is known, the pulling force applied to the bolt 18 can easily be calculated. Thus, no matter if during assembly or subsequent service a certain bolt elongation/ stretching force can be expected and if e.g. the bolt 18 is only elongated very little - even though the usual and required stretching force is applied - it could be concluded that the stretching device 34 by mistake has been mounted on a stud bolt 18 that has already been tightened. Such mistakes could be communicated to the database 8 and/or to the operator e.g. by means of an alarm, by means of the display on the hydraulic station 28, by means of the mobile unit 22 or other so that the operator may move the stretching device 34 to the correct stud bolt 18.

Such mistakes, data from the sensor means 12 and other operational data 13 of the power tool 3 could be logged and subsequently used for documentation purposes, for statistics, for planning maintenance of bolt connections or power tool 3 or other.

In an embodiment of the invention the stretching device 34 may also comprise means for unique detection of the bolt 18, the bolt connection, the general work area (e.g. by scanning a barcode or by reading an incorporated RFID tag) to further decrease the risk of e.g. servicing the wrong area or even the wrong wind turbine 1.

In this embodiment the hydraulic pressure is also being used for tightening the nut 35 when the bolt 18 has been elongated sufficiently and in this embodiment the pressure gauge will also act as tightening force detecting means 20 to detect the force being used during the tightening process. However, in another embodiment the nut 35 could be tightened manually or by other means than the stretching device 34.

Fig. 4 illustrates power tool system 1 in use in a wind farm. In this embodiment several power tools 3 is in operation simultaneously in different wind turbines 1 of the wind farm. In this embodiment all the power tools 3 communicates with a central database 8 to perform the validation enabling operation of the individual power tools 3. In this embodiment the power tool system 1 is also provided with centralized logging means 15 in the form of a logging database arranged to log data from all the power tools 3 in operation in the power tool system 1. However, in another embodiment the logging means 15 could be at least partly integrated with the database 8. Fig. 5 illustrates an embodiment of a structure of a power tool system 1 and Fig. 6 illustrates a diagram of an embodiment of the operation of a power tool system 1.

In this embodiment the operation of the power tool system 1 is controlled by first determining unique log-in information 6 of an operator 5 of the power tool 3 (pos. 37 in fig. 6), by first letting the operator log-in in this case via log-in means 4 arranged on the power tool 3. The log-in information 6 is transferred to control means 11 which also has access to operator data 9 in a database 8. If a lookup in the database 8 reveals that the operator - that is logging in - has the sufficient credentials - e.g. taken a specific course, is old enough, is working for the right company or other - the control means 11 will send a signal to the power tool 3 enabling that the power toll can operate (pos. 38 in fig. 6). This signal could e.g. switch the status of an electrical switch, open a valve or other. It could also merely send a code to the operator that had to be entered in the power tool 3 to enable operation. Operation of the power tool 3 would then be enabled until it is disabled again.

Disabling could e.g. happen automatically within a predefined time period after the power tool 3 was last used, if it was detected that the power tool 3 was moved from its original location, if the operator moved a predefined distance away from the power tool 3 or other. And/or the power tool 3 could be manually disabled by a central manager or by the operator. In another embodiment of the invention data regarding the position 36 of the power tool 3 is also communicated to the control means 11. The control means 11 will then will then look-up in position data 10 in a database 8 to check if the power tool 3 is in the correct position in relation to the current task. The current task could e.g. be supplied to the control means by the operator, it could be included in the position data 10 or the operator data 9 and then triggered by the unique log-on, or it could be supplied from another source such as a site manager, a maintenance program or other. The operation of the power tool 3 would then only be enabled if the control means validated the detected position 36 in relation to the position data 10.

The invention has been exemplified above with reference to specific examples of power tool systems 1, wind turbines 2, power tools 3 and other. However, it should be understood that the invention is not limited to the particular examples described above but may be designed and altered in a multitude of varieties within the scope of the invention as specified in the claims.

List

1. Power tool system

2. Wind turbine

3. Power tool

4. Log-in means

5. Operator

6. Log-in information

7. Communication means

8. Database

9. Operator data

10. Position data

11. Control means

12. Sensor means

13. Operational data of power tool

14. Sensor data transferring means

15. Logging means

16. Bolt connection

17. Elongation detection means

18. Bolt

19. Stretching force detecting means

20. Tightening force detecting means

21. Position determining means

22. Mobile unit

23. Mobile unit communication means

24. User interface

25. Bolt tensioning tool

26. Tower

27. Hydraulic extending means

28. Hydraulic station

29. Work data 30. Nacelle

31. Rotor

32. Blade

j j. Hub

34. Stretching device

35. Nut

36. Position of power tool

37. Determining unique log-in information

38. Enabling operation of power tool

39.

40. Hose

Claims

1. Power tool system (1) for a wind turbine (2) in a wind turbine site, said system comprising at least one power tool (3), log-in means (4) arranged to determine unique log-in information (6) of an operator (5) of said power tool (3), position determining means (21) arranged to determine or at least estimate a position (36) of said power tool (3), communication means (7) for communicating with a database (8) comprising operator data (9) and position data (10) of one or more wind turbines (2) or wind turbine components, and control means (1 1) arranged to enable operation of said power tool (3) in response to a validation of said log-in information (6) in relation to said operator data (9) in said database (8) and/or in response to a validation of said position (36) in relation to said position data (10) in said database (8).

2. A power tool system (1) according to claim 1, wherein said operator data (9) in said database (8) comprises information on said operator's credentials.

3. A power tool system (1) according to claim 2, wherein said credentials include proof of experience, certificates, diplomas or credits.

4. A power tool system (1) according to any of the preceding claims, wherein said position data (10) in said database (8) comprises information on a substantially exact or an at least partly estimated position of said one or more wind turbines (2) or wind turbine components.

5. A power tool system (1) according to any of the preceding claims, wherein said power tool system (1) further comprises sensor means (12) for detecting operational data (13) of said power tool (3).

6. A power tool system (1) according to claim 5, wherein said power tool system (1) further comprises sensor data transferring means (14) for transferring said operational data (13) from said sensor means (12) to logging means (15) of said power tool system (1).

7. A power tool system (1) according to claim 6, wherein said sensor data transferring means (14) comprises wireless data transferring means.

8. A power tool system (1) according to claim 6, wherein said logging means (15) is logging means (15) according to any of claims 20-23.

9. A power tool system (1) according to any of claims 5-8, wherein said sensor means (12) is arranged to detect tensioning of a bolt connection (16).

10. A power tool system (1) according to any of claims 5-9, wherein said sensor means (12) comprises elongation detection means (17) for detecting an elongation of a bolt (18) during a bolt tensioning process.

11. A power tool system (1) according to any of claims 5-10, wherein said sensor means (12) comprises stretching force detecting means (19) for detecting a bolt stretching force during a bolt tensioning process.

12. A power tool system (1) according to any of claims 5-11, wherein said sensor means (12) comprises tightening force detecting means (20) for detecting a tightening force during a nut tightening process. 13. A power tool system (1) according to any of the preceding claims, wherein said position determining means (21) comprises means for multilateration of radio signals.

14. A power tool system (1) according to any of the preceding claims, wherein said position determining means (21) comprises GPS means.

15. A power tool system (1) according to any of the preceding claims, wherein said position determining means (21) comprises Wi-Fi-based positioning means.

16. A power tool system (1) according to any of the preceding claims, wherein said position determining means (21) comprises Bluetooth tracking means.

17. A power tool system (1) according to any of the preceding claims, wherein said position determining means (21) comprises passive or active RFID tags. 18. A power tool system (1) according to any of the preceding claims, wherein said power tool system (1) comprises mobile unit communication means (23) for communicating with a mobile unit (22) of said operator (5).

19. A power tool system (1) according to claim 18, wherein said mobile unit (22) comprises a mobile phone.

20. A power tool system (1) according to any of the preceding claims, wherein said power tool system (1) further comprises logging means (15).

21. A power tool system (1) according to claim 20, wherein said logging means (15) is arranged for logging operational data (13) of said power tool (3).

22. A power tool system (1) according to claim 20 or 21, wherein said logging means (15) is arranged for logging operational data (13) of said operator (5).

23. A power tool system (1) according to any of claims 20-22, wherein said logging means (15) is arranged for logging data from said position determining means (21). 24. A power tool system (1) according to any of the preceding claims, wherein said log-in means (4) comprises a user interface (24).

25. A power tool system (1) according to any of the preceding claims, wherein said log-in means (4) comprises a scanner.

26. A power tool system (1) according to any of the preceding claims, wherein said log-in means (4) comprises a card reader.

27. A power tool system (1) according to any of the preceding claims, wherein said communication means (7) comprises wireless communication means (7).

28. A power tool system (1) according to any of the preceding claims, wherein said power tool (3) comprises a bolt tensioning tool (25). 30. A power tool system (1) according to any of the preceding claims, wherein said power tool (3) is a stud tensioning unit (25) for tensioning stud bolts (18) in a tower (26) of said wind turbine (2).

31. A power tool system (1) according to claim 30, wherein said stud tensioning unit (25) comprises hydraulic extending means (27) arranged to extend said stud bolt (18) and a hydraulic station (28) arranged to generate a hydraulic pressure driving said hydraulic extending means (27).

32. A power tool system (1) according to any of the preceding claims, wherein said control means (11) is arranged to only enable operation of said power tool (3) if said log-in information (6) is validated in relation to said operator data (9) in said database (8) and if said position (36) is validated in relation to said position data (10) in said database (8). 33. A method for controlling operation of a power tool system (1) for a wind turbine (2) in a wind turbine site, said method comprising the steps of:

• determining unique log-in information (6) of an operator (5) of said power tool (3),

• enabling operation of said power tool (3) in response to a validation of said log-in information (6) in relation to operator data (9) in a database (8).

34. A method according to claim 33, wherein said method further comprises the step of determining or at least estimating a position (36) of said power tool (3).

35. A method according to claim 34, wherein said method further comprises the step of communicating said position (36) of said power tool (3) to said control means (11) enabling said operation, wherein said control means (11) also has access position data (10) of one or more wind turbines (2) or wind turbine components.

36. A method according to claim 35, wherein said method further comprises the step of enabling operation of said power tool (3) in response to a validation of said position (36) of said power tool (3) in relation to said position data (10) in said database (8).

37. A method according to any of claims 33-36, wherein work data (29) is communicated to said operator (5) after said operation is enabled.

38. A method according to claim 37, wherein said work data (29) is communicated to said operator (5) by means of said power tool (3).

39. A method according to claim 37 or 38, wherein said work data (29) is communicated to said operator (5) by means of a mobile unit (22). 40. A method according to any of claims 37-39, wherein said work data (29) is communicated to said operator (5) by means of a mobile phone.

41. A method according to any of claims 34-40, wherein said work data (29) comprises information regarding substantially exact work location.

42. A method according to any of claims 34-41, wherein said work data (29) comprises information regarding a tensioning sequence of a bolt array.

43. A method according to any of claims 34-42, wherein said work data (29) comprises information regarding operation of said power tool (3).

44. A method according to any of claims 34-43, wherein said work data (29) comprises information regarding status of said power tool (3). 45. A method according to any of claims 33-44, wherein said operation of said power tool (3) is disabled again a predefined time period after operation of said power tool (3) has stopped.

46. A method according to any of claims 33-45, wherein said operation of said power tool (3) is disabled again if said power tool (3) is moved a predefined distance away from a position at which said operation was enabled.

47. A method according to any of claims 33-46, wherein said operation of said power tool (3) is disabled again if said operator (5) moves a predefined distance away from said power tool (3).

48. A method according to any of claims 33-47, wherein said method also comprises the step of tracking a position of said operator (5).

49. A method according to any of claims 33-48, wherein said method also comprises the step of tracking a position of said power tool (3).

50. A method according to any of claims 33-49, wherein said log-in information (6) and said position (36) of said power tool (3) is logged.

51. A method according to any of claims 33-50, wherein said log-in information (6) and said position (36) of said power tool (3) is logged together with operational data (13) of said power tool (3).

52. A method according to any of claims 33-51, wherein said method is a method for controlling operation of a power tool system (1) according to any of claims 1-32.

53. Use of a power tool (3) system (1) according to any of claims 1-32 for tightening bolts (18) in a wind turbine (2) in a wind farm.