WO2018010745A1

WO2018010745A1 - A method of managing access in a site for one or more wind turbines from a central station and system therefore

Info

Publication number: WO2018010745A1
Application number: PCT/DK2016/050250
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

The invention relates to a method of managing access in a site for one or more wind turbines from a central station with one or more databases including definitions of a plurality of area zones in said site wherein at least two area zones include different access levels and a plurality users or types of users with qualifications for one or more of said different access levels to access one or more of said area zones. The method comprising the steps of: Providing a mobile unit for a user moving in said site wherein the unit includes an identification application, an identification code for identifying the user and communication means for communicating with said central station, Monitoring access of the user in one of said area zones at said central station by receiving said identification code from the provided mobile unit running said identification application, Retrieving qualifications of the user in said one or more databases with use of the identification code communicated from the provided mobile unit, Controlling qualifications of the user in relation to the access level of the accessed area zone in said one or more databases, and Allowing or not allowing access to said area zone for the user in response to the control of qualifications and access level. The invention also relates to a system for managing access in a site for one or more wind turbines.

Description

A METHOD OF MANAGING ACCESS IN A SITE FOR ONE OR MORE WIND TURBINES FROM A CENTRAL STATION AND SYSTEM THEREFORE

Field of the invention

The invention relates to a method of managing access in a site for one or more wind turbines from a central station.

The invention also relates to a system for managing access in a site for one or more wind turbines.

Background of the invention

Wind turbines supplying electricity to a public utility grid are often grouped as a wind farm at a site. The site of a wind farm may consist of several individual wind turbines and cover an extended area of square kilometres on land. A wind farm can also be located offshore and in a similar manner cover an extended area of square kilometres at sea.

A wind turbine comprises different mechanical and electric systems and as such requires service and maintenance by service personnel after the wind turbine has become operational e.g. as part of a wind farm. Other types of personnel may also be present in a site of wind turbines such as security guards patrolling the site or truck drivers delivering wind turbine parts at a location within the site.

As the site of a wind farm often covers an extended area of square kilometres accessing and navigating within the site may be challenging. Use of mobile phones and GPS system has previously been suggested as a guidance system for personnel in the site of a wind farm e.g. for service personnel having to locate a specific wind turbine in the wind farm. However, the known guidance system and similar solutions do not provide a central understanding and documentation of the personnel which access and navigate within the site of wind turbines. Accordingly, it is an object of the invention to provide a method and system which seeks to overcome this problem.

Summary of the invention

The invention relates to a method of managing access in a site for one or more wind turbines from a central station with one or more databases including definitions of a plurality of area zones in said site wherein at least two area zones include different access levels and a plurality users or types of users with qualifications for one or more of said different access levels to access one or more of said area zones, said method comprising the steps of: providing a mobile unit for a user moving in said site wherein the unit includes an identification application, an identification code for identifying the user and communication means for communicating with said central station, monitoring access of the user in one of said area zones at said central station by receiving said identification code from the provided mobile unit running said identification application, retrieving qualifications of the user in said one or more databases with use of the identification code communicated from the provided mobile unit, controlling qualifications of the user in relation to the access level of the accessed area zone in said one or more databases, and allowing or not allowing access to said area zone for the user in response to the control of qualifications and access level.

Hereby is advantageously achieved a central control of users which are allowed access to a site of one or more wind turbines. The central control also may also define and allow restrictions on access by users to different area zones of the site. Further, it is possible to provide a central understanding and documentation of the allowed access by users e.g. for future documentation of users and performed work actions in the site or for immediate documentation of users present in the site for example in a situation requiring evacuation of users from area zones or from the entire site.

The term "allowing or not allowing access" in this context should be interpreted broadly as an immediate or later action or sanction in response to an allowed or non- allowed access in an area zone by a mobile unit.

According to an embodiment, the interior of said wind turbines or interior sections of said wind turbines such as tower/tower parts, nacelle and/or hub are defined in said databases as area zones with individual access levels. The technical complexity of a modern wind turbine makes it advantageously to define individual access levels for the interior of a wind turbine to ensure that only users with the right qualification are allowed access and especially definitions for different interior sections of the wind turbine comprising for example delicate or potentially dangerous technical wind turbine systems. According to an embodiment, further spaces of said site such as work, control and technical rooms, repair workshops, roads and/or exterior spaces close to wind turbines are defined in said databases as area zones with individual access levels. The further spaces may advantageously comprise individual access levels for different reasons such as being spaces including delicate or expensive technical means, being potentially dangerous spaces for users or spaces with no relevance for the users as navigational advices.

Preferably, said qualifications of a user or types of users are defined in said databases as certificates and diplomas of professional skill and training, general or site approvals, company employments and/or employment titles. Hereby it is possible to only allow the right qualified users into the area zones with restricted access levels e.g. only allowing skilled electricians and similar qualified users into the electric sections of a wind turbine.

According to an embodiment, said access levels at least are defined as a level of unrestricted access for said users or types of users and a level of restricted access for some of said users or types of users. It is advantageous that the already defined users or types of users have un-restricted access to some area zones of the site but only access to other area zones if they comprise the right qualifications e.g. a delivery truck driver may use the site roads but has not qualifications to be allowed access to any area zone of a wind turbine within the site.

According to another embodiment, said access levels at least are defined as a level of un-restricted access for said users or types of users and a number of different levels of restricted access for some of said users or types of users in relation to said qualifications. It is advantageous that the already defined users or types of users have un-restricted access to some area zones of the site and wind turbines but not access to other area zones e.g. skilled workers employed by one company having access to the area zones of the wind turbines assigned to the company but not access to other sections of the wind turbines without relevance for their work assignments.

Preferably, data of allowed accesses with a mobile unit is documented in a documentation database of said one or more databases. Hereby it is possible to better "track and trace" past actions performed in an area zone by the data documentation of users access to the area zone.

According to an embodiment, the step of allowing or not allowing access to an area zone for a mobile unit includes an operational action from the central station to one or more of said wind turbines. Hereby it is possible to increase work safety in the site as user access to an area zone is centrally allowed e.g. ensuring that a user is not allowed access to an area zone of a wind turbine still in operation such as an active high voltage area zone.

According to an embodiment, said central station allows or facilitates a change of operational status for one or more of said wind turbines e.g. to an idle or stopped status. The idling or stopped status of a wind turbine is often necessary if a user is to access the wind turbine and it is advantageous to allow user access and change operational status for the wind turbine as the same or a common central action.

According to an embodiment, the central station allows or facilitates access to said one or more wind turbines or access to a section or sections of said one or more wind turbines. It is advantageously that access to a wind turbine or sections within the wind turbine is centrally allowed or facilitated in response to knowledge and control of qualifications of the user requesting access into the wind turbine or wind turbine sections.

Advantageously, the user initially loads the identification code into the mobile unit with reading means of the unit. Hereby it is possible to link a specific user to the defined qualifications of the user in databases at the central station via the mobile unit and data communication between the mobile unit and central station.

According to an embodiment, the mobile unit communicates a location code or image of an area zone to the central station. Hereby it is possible in an advantageously way to link a specific location of the user wanting to enter an area zone to the defined access level of the area zone and the qualifications of the user in databases at the central station via the mobile unit and data communication between the mobile unit and central station

According to another embodiment, the mobile unit communicates a GPS location of an area zone to the central station. Hereby it is possible in an advantageously way to continuously link a specific location of the user wanting to enter an area zone to the defined access level of the area zone and the qualifications of the user in databases at the central station via the mobile unit and data communication between the mobile unit and central station.

According to a further embodiment, communication to the mobile unit is established in a non-allowed access to an area zone. Hereby it is ensured that the user may be quickly alerted about non-allowed access to an area zone e.g. via communication from the central station or communication from a security guard in the site.

According to an even further embodiment, the central station cancels or restricts the use of an identification code in said mobile unit in a non-allowed access of an area zone. Hereby is achieved an advantageous embodiment of the invention whereby the safety standards of a site may continuously be maintained and improved.

Advantageously, communication from the central station to a user of a mobile unit is established via an optical head-mounted display e.g. shaped as a pair of eyeglasses carried by the user. Hereby it is possible for the user to perform different work actions unrestricted while being allowed access to an area zone.

The invention also relates to a system for managing access in a site for one or more wind turbines comprising: at least one mobile unit for a user moving in said site including an identification application, an identification code for identifying the user and communication means for communicating with a central station, and said central station including: one or more databases with definitions of a plurality of area zones in said site wherein at least two area zones include different access levels and a plurality users or types of users with qualifications for one or more of said different access levels to access one or more of said area zones wherein said users are provided with said mobile units when moving in said site, communication means for communicating with said mobile units, and processor means for performing a method according to any of claims 1 to 17.

Hereby is achieved an advantageous system according to the invention.

Advantageously, said identification code is a QR code and/or one or more of said area zones include a location code or image such as a QR code.

In an advantageous embodiment, said mobile unit is a smartphone or a similar mobile telephone with an advanced operating system ensuring that at least the identification application with the identification code can be executed.

In another advantageous embodiment, said mobile unit includes a reader for reading an identification code and/or a location code or image such as a reader for QR codes.

In a further embodiment, said mobile unit is a passive unit communicating indirectly with said central station via stationary communication units at access means of said area zones. Hereby it is possible to provide the user with a simple mobile unit having the identification code pre-installed in a permanent memory chip e.g. a pre-installed RFID or QR code which may be presented for stationary communication units located for example at the site access gate and at access doors of the wind turbines in the site and with a direct communication line to the central station for relaying the identification code of the simple mobile unit.

In an even further embodiment, said central station is part of a Supervisory Control And Data Acquisition (SCADA) centre for said wind turbines or is a separate station with a communication connection to said SCADA centre. Hereby it is possible to advantageously coordinate any access of users to the site with the general control and operation of the wind turbines in the site as performed from the SCADA centre.

Advantageously, said central station includes display means for displaying the mobile units moving inside the site. Hereby it is possible to display and document users present in the site for example in a situation requiring evacuation of users from area zones or from the entire site.

In an advantageous embodiment, said site of one or more wind turbines is a site for an on-shore or offshore wind farm.

Advantageously, said one or more wind turbines and/or site comprise access means controlled from the central station such as remote controlled door locks and/or gate locks and beams. Hereby it is possible to provide easy access to area zones within the site for users with the right or necessary qualifications and also deny and prevent any access for users without the right or necessary qualifications.

Advantageously, said databases include a site documentation database comprising site layout drawings, work schedules for users moving in the site, code of conduct for the site, Quality, Health, Safety and Environment (QHSE) issues for the site and/or other site work related subject matters. Hereby it is possible to provide the user with relevant site documentation in his mobile unit at an area zone after the central station has performed and allowed access to the area zone. Figures

Embodiments of the invention will be described, by way of example only with reference to the drawings, in which

Fig. 1 shows a modern wind turbine,

Fig. 2 shows a site of wind turbines and a central station according to the

invention,

Fig. 3a shows schematically a first embodiment of a system managing access in a site for one or more wind turbines according to the invention

Fig. 3b shows schematically a further embodiment of a system managing access in a site for one or more wind turbines according to the invention, and Fig. 4 shows a flow diagram for a method of managing access in a site for one or more wind turbines from a central station according to the invention.

Description of embodiments

Fig. 1 shows an example of a modern wind turbine 1 such as an on- or offshore wind turbine. The wind turbine comprises a tower 3 with an access door to the interior of a wind turbine 7 at ground level 2.

A wind turbine nacelle 4 is positioned on top of the tower and the wind turbine hub 5 is attached to a main shaft rotatable connected to an electric generator located in the nacelle. The three rotor blades 6 of the wind turbine rotor 5 are also attached to the hub e.g. via pitch mechanisms for pitching the rotor blades in and out of the wind.

The generated electric energy from the wind turbine 1 is normally supplied to a public utility grid for transmission to the consumers.

Fig. 2 shows a site 8 of wind turbines 1 and a central station 14 according to the invention. The site 8 and the three wind turbines 1 is shown in the Figure as an onshore wind farm with an access gate 9 to the surrounding community and roads 10 between the gate and the wind turbines. The site also comprises a further building 11 according to the Figure such as a control room, a transformer station, a repair workshop or other types of technical housing in the site of a wind farm. The further building is also shown as having road access from the access gate and wind turbines within the site.

Fig. 2 illustrates that a user for example in a car or a similar motor vehicle may enter the extended area of the site 8 via an access gate 9 and easily continue to any one of the wind turbines 1 or further building 11. The user is provided with a mobile unit 12, 12a-d when entering the site 8.

Fig. 2 also illustrates that access of users in the site 8 is monitored from a central station 14 via data communication 13 from the mobile units 12, 12a-d entering or moving inside the site 8.

The mobile unit 12, 12a-d includes an identification application, an identification code for identifying the user and communication means for data communicating with the central station 14. The identification code may for example be a QR code which is initially provided to the user. The identification code is preferably read into the mobile unit with an identification code reader or a digital camera in the mobile unit 12, 12a-d capable of reading an identification code. The identification code may also in a simpler embodiment be provided as a code of letters and numbers which is initially typed into the memory of the mobile unit by using the keyboard of the unit or other known forms of user identifications such as automatic fingerprint or similar biometric identifications. The mobile unit 12, 12a-d may also include GPS location means.

The mobile unit 12, 12a-d is preferably a smartphone or a similar mobile telephone with an advanced operating system capable of running the identification application and directly communicating with the central station 14.

The mobile units 12, 12a-d are illustrated in the Figure as being in different locations at and inside the site 8 e.g. the mobile unit 12a at the access gate to the site 8, the mobile unit 12 in an open area with a distance to the nearest wind turbine 1 and further building 11, the mobile unit 12b at the access door of a wind turbine 1, the mobile unit 12c on the site road 10 from the access gate to a wind turbine 1 e.g. in a motor vehicle and the mobile unit 12c moving up inside the tower of a wind turbine 1.

The central station 14 includes computer processor means PM for processing data communication 13 received from mobile units 12, 12a-d at or in a site of one or more wind turbines 8 via communication means CM in the central station and data retrieved from one or more database DBi_-n in the central station. The result of the processed data by the processor means PM is used in managing access to the site for mobile units 12, 12a-d. The processed data may also be stored in a documentation database as well as displayed on display means DM in the central station 14 e.g. to illustrate the number of users and mobile units 12, 12a-d present in the site. One or more of the databases DBi_-n in the central station 14 have stored qualifications of the users before they are provided with the mobile units 12, 12a-d such qualifications as certificates and diplomas of professional skill and training, tool and equipment approvals, company employments and/or employment titles for the users.

The specific qualifications of a user are identified and retrieved in the database by the identification code communicated to the central station 14 by the provided mobile unit 12, 12a-d as a form of retrieval key. Other of the databases DBi_-n in the central station 14 have stored definitions of a plurality of area zones and access levels of the area zones in the site of wind turbines which will be explained below in more details in connection with Figs. 3a and 3b.

The mobile unit may in an embodiment also have a wired or wireless connection to an optical head-mounted display for a user e.g. a display shaped as a pair of eyeglasses and communication means with a Bluetooth connection to the mobile unit. The pair of eyeglasses may display relevant information for the user from for example a site documentation database in the central station 14. The site documentation database may comprise site layout drawings, work schedules for users moving in the site, code of conduct for the site, Quality, Health, Safety and Environment (QHSE) issues for the site 8 and/or other site work related subject matters. The pair of eyeglasses may especially be part of the personal work protection equipment for a user by providing information and warnings about safety issues on the site and in relation to the wind turbines but may also be used as advanced safety goggles providing the user with eye protection.

The mobile unit with an optical head-mounted display may also be used for general communication for example with the central station 14 and other mobile units 12, 12a- d present in the site 8. The mobile unit 12, 12a-d may also in an embodiment of the invention be a passive unit communicating indirectly with the central station 14 via stationary communication units located at access means of the area zones. The passive mobile unit has the identification code of the user pre-installed in a permanent memory chip e.g. a pre-installed RFID or QR code which may be presented for one stationary communication unit when the user is trying to enter the site at the access gate or trying to access a wind turbine through the wind turbine door wherein the gate beam and door lock are examples of access means for area zones. Stationary communication units at the area zones have communication means and a direct communication line to the central station 14 for relaying the identification code as communicated from the passive mobile unit. The central station may remote control the relevant access means when the identification code has been validated at the central station as belonging to a user with qualifications to enter the area zone. The above-mentioned documentation database of the databases may store any access data for users accessing area zones of the site for instant or future evaluations.

Fig. 3a shows schematically a first embodiment of a system managing access in a site for one or more wind turbines according to the invention.

The figure shows the site of Fig. 2 wherein the site 8 is divided into a plurality of area zones with two area zones 15, 16 having different access levels for users. The two area zones with different access levels are illustrated as the exterior area of the site (15 / level I) and interior area of the wind turbines and further building in the site (16 / level II), respectively.

The access level in the area zone 15 labelled level I in the site may be un-restricted or low restricted for any users such as the users provided with mobile units 12e and 12f. The users provided with mobile units 12e and 12f initially access the area zone 15 of the site via access gate 9 and each mobile unit may communicate the identification code of the user to the central station 14. The central station 14 retrieves the qualifications of the user requesting access to the area zone 15 in the databases DBi_-n. The qualifications of a user are structured in the databases in order for the identification code of the user may be used as a retrieval key. The central station controls the retrieved qualifications of the user with the access level (level I) of the area zone 15. The user is allowed to enter the area zone 15 if the user has the necessary qualifications to fulfil the access level (level I) of the area zone 15 such as a correct certificate and/or diploma of professional skill and training, general or site approvals, company employment and/or employment title.

Otherwise the user is denied access to the area zone 15 e.g. by not activating a gate beam or similar access means of the area zone 15 and/or by communicating a deny message to the mobile unit and/or by contacting the user in other ways. The Figure illustrates that the user 12f also comprises the necessary qualifications to fulfil the access level (level II) of the area zone 16 and has been allowed by the central station 14 to enter area zone 16 such as the interior of a wind turbine 1. The user 12f may for example have the qualifications in the databases of a professional skill and training diploma together with a site approval for using a specific power tool in the area zone 16.

The user 12e is illustrated as only having the qualifications to be allowed to move in area zone 15 (level I) including the site roads 10 e.g. the user being a truck driver on route to deliver goods outside the further building 11.

The users may communicate a location code to the central station 14 with the provided mobile units 12e, 12f but the access gate 9 and wind turbine doors 7 at the area zones 15, 16 may also be provided with a location code such as a QR code. The location codes are read by the mobile units 12e, 12f e.g. by using build-in cameras when requesting access at the area zones and communicated to the central station 14. The mobile units 12e, 12f may also use the build-in cameras to communicate location images for the mobile units to the central station 14 for determining the area zone which the users are located in e.g. located in an outside area zone or an inside area zone of a wind turbine in the site.

The specific area zone of a user may be identified and retrieved in the databases by the location code communicated to the central station 14 by the provided mobile unit 12e, 12f as a form of retrieval key. Fig. 3b shows schematically a further embodiment of a system managing access in a site for one or more wind turbines according to the invention.

The figure also shows the site of Fig. 2 wherein the site 8 is divided into a plurality of area zones 15-20 with many area zones having different access levels (levels I to VI) for the users with mobile units 12, 12a-f.

The different area zones as defined in the databases DBi_-nmay include:

15 / Level I - exterior area of the site with unrestricted or low restricted access level for the users defined in the databases.

16 / Level II - an interior area of a wind turbine 1 in the site with a restricted access level. The access level is exemplified above in connection with the description of Fig. 3a.

17 / Level III - an interior area of the above-mentioned wind turbine 1 with a higher restricted access level. Allowed access to the level may for example require users with higher qualifications defined in the databases in relation to skills and training and/or approvals than the users allowed access to level II. 18 / Level VI - a first interior area of a wind turbine 1 in the site with restricted access level for some users. Allowed access to the level may for example require users with one type of qualifications defined in the databases such as work skills and training within an electrical field.

19 / Level V - a second interior area of the above-mentioned wind turbine 1 with restricted access level for some other users. Allowed access to the level may for example require users with another type of qualifications defined in the databases than level VI such as work skills and training within a mechanical field.

20 / Level IV - interior area of the further building 11 in the site with restricted access level for the users. Allowed access to the level may for example be a limited amount of users having the qualifications of being from the same company. Fig. 4 shows a flow diagram with steps for a method of managing access in a site for one or more wind turbines from a central station according to the invention.

The steps 21 to 27 of the flow diagram include: Step 21) To provide a mobile unit for a user moving in the site wherein the unit includes an identification application, an identification code for identifying the user and communication means for communicating with said central station.

Step 22) To monitor access of the user in one of said area zones at said central station by receiving said identification code from the provided mobile unit running said identification application.

Step 23) To retrieve qualifications of the user in said one or more databases with use of the identification code communicated from the provided mobile unit. Steps 24 - 25) To control qualifications of the user in relation to the access level of the accessed area zone in said one or more databases.

Steps 26 -27) To allow or not allow / deny access to said area zone for the user in response to the control of qualifications and access level.

The latter of the method steps (step 27) in the Figure suggests to wait for new access requests from the mobile unit to be controlled but a denial of access by the method may also prompt further actions for the user of the unit. A subsequent action to a non- allowed access of an area zone may be the central station cancelling or restricting the use of an identification code in the mobile unit.

Further, a communication call or other type of contact to the mobile unit and user may also be established from the central station or from a security guard if a non-allowance of access to an area zone is the result of the above method and this result is considered of particular significance.

In the above description, various embodiments of the invention have been described with reference to the drawings, but it is apparent for a person skilled within the art that the invention can be carried out in an infinite number of ways, using e.g. the examples disclosed in the description in various combinations, and within a wide range of variations within the scope of the appended claims.

References

1. On- or offshore wind turbine

2. Ground level

3. Wind turbine tower

4. Wind turbine nacelle

5. Wind turbine hub

6. Wind turbine rotor with three rotor blades

7. Access door to the interior of a wind turbine

8. Site for one or more wind turbines such as a site of an on- or offshore wind farm

9. Access gate in the site for one or more wind turbines

10. Roads inside the site

11. Further building such as control room, transformer station, repair workshop or other types of technical housing in the site

12, 12a-f. Mobile units including identification codes

13. Data communication

14. Central station

15. Area zone with access level I within the site a site of wind turbines

16. Area zone with access level II within the site a site of wind turbines 17-20. Area zones with access levels III to VI within a site of wind turbines

21-27. Flow diagram steps

CM. Communication means in the central station

DBi-n. One or more databases in the central station

DM. Display means in the central station

PM. Processor means in the central station

Claims

1. Method of managing access in a site for one or more wind turbines from a central station with one or more databases including definitions of a plurality of area zones in said site wherein at least two area zones include different access levels and a plurality users or types of users with qualifications for one or more of said different access levels to access one or more of said area zones, said method comprising the steps of: providing a mobile unit for a user moving in said site wherein the unit includes an identification application, an identification code for identifying the user and communication means for communicating with said central station, monitoring access of the user in one of said area zones at said central station by receiving said identification code from the provided mobile unit running said identification application, retrieving qualifications of the user in said one or more databases with use of the identification code communicated from the provided mobile unit, controlling qualifications of the user in relation to the access level of the accessed area zone in said one or more databases, and allowing or not allowing access to said area zone for the user in response to the control of qualifications and access level.

2. Method according to claim 1 where interior of said wind turbines or interior sections of said wind turbines such as tower/tower parts, nacelle and/or hub are defined in said databases as area zones with individual access levels.

3. Method according to claim 1 or 2 where further spaces of said site such as further buildings e.g. work, control and technical rooms, repair workshops, roads and/or exterior spaces close to wind turbines are defined in said databases as area zones with individual access levels.

4. Method according to any of claims 1 to 3 where said qualifications of a user or types of users are defined in said databases as certificates and diplomas of professional skill and training, general or site approvals, company employments and/or employment titles.

5. Method according to any of claims 1 to 4 where said access levels at least are defined as a level of un-restricted access for said users or types of users and a level of restricted access for some of said users or types of users.

6. Method according to any of claims 1 to 4 where said access levels at least are defined as a level of un-restricted access for said users or types of users and a number of different levels of restricted access for some of said users or types of users in relation to said qualifications.

7. Method according to any of the preceding claims where data of allowed accesses with a mobile unit is documented in a documentation database of said one or more databases.

8. Method according to any of the preceding claims where the step of allowing or not allowing access to an area zone for a mobile unit includes an operational action from the central station to one or more of said wind turbines.

9. Method according to any of the preceding claims where said central station allows or facilitates a change of operational status for one or more of said wind turbines e.g. to an idle or stopped status.

10. Method according to any of the preceding claims where the central station allows or facilitates access to said one or more wind turbines or access to a section or sections of said one or more wind turbines.

11. Method according to any of the preceding claims where the user initially loads the identification code into the mobile unit with reading means of the unit.

12. Method according to any of the preceding claims where the mobile unit communicates a location code or image of an area zone to the central station.

13. Method according to any of the preceding claims where the mobile unit communicates a GPS location of an area zone to the central station.

14. Method according to any of the preceding claims where communication to the mobile unit is established in a non-allowed access to an area zone.

15. Method according to any of the preceding claims where the central station cancels or restricts the use of an identification code in said mobile unit in a non-allowed access of an area zone.

16. Method according to any of the preceding claims where communication from the central station to a user of a mobile unit is established via an optical head-mounted display e.g. shaped as a pair of eyeglasses carried by the user.

17. Method according to any of the preceding claims where said communication means in the mobile unit communicates directly or indirectly with said central station.

18. A system for managing access in a site (8) for one or more wind turbines (1) comprising: at least one mobile unit (12, 12a-f) for a user moving in said site (8) including an identification application, an identification code for identifying the user and communication means for communicating with a central station (14), and said central station (14) including: one or more databases (DBl-n) with definitions of a plurality of area zones (15-20) in said site (8) wherein at least two area zones include different access levels and a plurality users or types of users with qualifications for one or more of said different access levels to access one or more of said area zones wherein said users are provided with said mobile units when moving in said site, communication means (CM) for communicating with said mobile units (12, 12a-f), and processor means (PM) for performing a method according to any of claims 1 to 17.

19. System according to claim 18 wherein said identification code is a QR code.

20. System according to claim 18 or 19 wherein one or more of said area zones (15- 20) include a location code or image such as a QR code.

21. System according to any of claims 18 to 20 wherein said mobile unit (12, 12a-f) is a smartphone or a similar mobile telephone with an advanced operating system.

22. System according to any of claims 18 to 21 wherein said mobile unit (12, 12a-f) includes a reader for reading an identification code and/or a location code or image such as a reader for QR codes.

23. System according to any of claims 18 to 22 wherein said mobile unit (12, 12a-f) includes GPS location means.

24. System according to any of claims 18 to 20 wherein said mobile unit (12, 12a-f) is a passive unit communicating indirectly with said central station (14) via stationary communication units at access means of said area zones (15-20).

25. System according to any of claims 18 to 24 wherein said qualifications of user or types of users include certificates and diplomas of professional skill and training, tools and equipment approvals, company employments and/or employment titles.

26. System according to any of claims 18 to 25 wherein said central station (14) is part of a Supervisory Control And Data Acquisition (SCAD A) centre for said wind turbines (1) or is a separate station with a communication connection to said SCAD A centre.

27. System according to any of claims 18 to 26 wherein said central station (14) includes display means (DM) for displaying the mobile units (12, 12a-f) moving inside the site (8).

28. System according to any of claims 18 to 27 wherein said mobile unit (12, 12a-f) includes an optical head-mounted display for a user e.g. shaped as a pair of eyeglasses.

29. System according to any of claims 18 to 28 wherein said site (8) of one or more wind turbines (1) is a site for an on-shore or offshore wind farm.

30. System according to any of claims 18 to 29 wherein said one or more wind turbines (1) and/or site (8) comprise access means controlled from the central station (14) such as remote controlled door locks of and/or gate locks and beams.

31. System according to any of claims 18 to 30 wherein said databases (DBi_-n) include a documentation database for data of allowed accesses with a mobile unit in the site.

32. System according to any of claims 18 to 31 wherein said databases (DBi_-n) include a site documentation database comprising site layout drawings, work schedules for users moving in the site, code of conduct for the site, Quality, Health, Safety and Environment (QHSE) issues for the site (8) and/or other site work related subject matters.