IMPROVEMENTS RELATING TO THE MANUFACTURE OF A WIND TURBINE COMPONENT

Abstract

In a first aspect of the invention there is provided a method of making a wind turbine component, the method comprising supporting a layup (14) of fibrous reinforcing material in a mould (12); providing a supply of resin (16); providing a supply of hardener (20) comprising at least a first hardener (20a) and a second hardener (20b), the second hardener being faster than the first hardener; mixing resin with the first and/or second hardener to create a resin mixture (24); supplying the resin mixture (24) to the layup (14) during an infusion process; monitoring one or more process parameters of the infusion process; and controlling the speed of the hardener (20) by varying the relative proportions of the first and second hardeners (20a, 20b) in the resin mixture (24) during the course of the infusion process in dependence upon the one or more process parameters.

Claims

1. A method of making a wind turbine component, the method comprising: supporting a layup of fibrous reinforcing material in a mould; providing a supply of resin); providing a supply of hardener comprising at least a first hardener and a second hardener, the second hardener being faster than the first hardener; mixing resin with the first and/or second hardener to create a resin mixture; supplying the resin mixture to the layup during an infusion process; monitoring one or more process parameters of the infusion process; and controlling the speed of the hardener by varying the relative proportions of the first and second hardeners in the resin mixture during the course of the infusion process in dependence upon the one or more process parameters.

2. The method of claim 1, wherein the one or more process parameters are selected from the group comprising: ambient temperature, resin mixture temperature, elapsed time since start of infusion process, position of a resin mixture flow front and a vacuum pressure in the mould.

3. The method of claim 1, further comprising determining an initial mix ratio of the first and second hardeners based upon one or more process parameters.

4. The method of claim 1, further comprising mixing the resin predominantly or exclusively with the first hardener at the start of the infusion process.

5. The method of claim 1, further comprising increasing the speed of the hardener by increasing the proportion of the second hardener in the resin mixture as the infusion process progresses.

6. The method of claim 1, wherein the mould comprises a plurality of zones each having a respective resin inlet, and wherein the method further comprises: supplying the resin mixture to the layup in a first zone through a first resin inlet; monitoring the position of a flow front of the resin mixture; and increasing the proportion of the second hardener in the resin mixture as the flow front moves towards a second zone adjacent to the first zone.

7. The method of claim 6, wherein when the flow front of the resin mixture reaches the second zone, the method further comprises: reducing the speed of the hardener by reducing the proportion of the second hardener in the resin mixture; and supplying the resin mixture to the layup in the second zone through a second resin inlet.

8. The method of claim 7, further comprising increasing the proportion of the second hardener in the resin mixture as the flow front moves towards a third zone adjacent to the second zone.

9. The method of claim 6, further comprising curing the resin mixture in one or more zones.

10. The method of claim 1, further comprising monitoring one or more process parameters of the infusion process.

11. The method of claim 1, further comprising controlling the infusion process using an artificial intelligence system configured to receive feedback from one or more cameras and/or sensors and to self-optimise settings of the infusion process.

12. An apparatus for making a wind turbine component, the apparatus comprising: a mould for supporting a layup of fibrous reinforcing material; a supply of resin; a supply of hardener comprising at least a first hardener and a second hardener, the second hardener being faster than the first hardener; a resin mixing and supply system for mixing the resin with the first and/or the second hardener to create a resin mixture, and for supplying the resin mixture to the layup during an infusion process; and a control system configured to control the speed of the hardener by varying the relative proportions of the first and second hardeners in the resin mixture during the infusion process, based upon one or more process parameters of the infusion process.

13. The apparatus of claim 12, wherein the supply of hardener comprises a hardener metering system arranged to mix the first and second hardener according to a mix ratio determined by the control system, and to supply a defined quantity of the mixed hardener to the resin mixing and supply system.

14. The apparatus of claim 12, further comprising one or more sensors for determining one or more process parameters of the infusion process.

15. The apparatus of claim 12, further comprising a camera arranged above the mould and configured to monitor the temperature and/or flow front of the resin mixture during the infusion process.

16. The method of claim 3, wherein the one or more process parameters include one or more of ambient temperature, mould temperature, layup temperature and resin initial temperature.

17. The method of claim 9, further comprising curing the resin mixture in one or more zones by applying heat to said one or more zones, whilst simultaneously supplying resin mixture to one or more other zones.

18. The method of claim 10, wherein monitoring one or more process parameters of the infusion process includes monitoring one or more of temperature and/or position of a resin mixture flow front using a camera located above the mould.

19. The method of claim 11, wherein self-optimising settings of the infusion process include self-optimising one or more of vacuum pressure, resin supply pressure, resin mixture flow rate, hardener mix ratio and curing temperatures.

20. The apparatus of claim 15, wherein the camera is an infra-red camera.

Description

BRIEF DESCRIPTION OF FIGURES

[0060] Embodiments of the present invention will now be described by way of non-limiting example only, with reference to the accompanying figures, in which:

[0061] FIG. 1 is a schematic diagram representing apparatus for making a wind turbine component;

[0062] FIGS. 2a to 2c show a resin mixture infusing a layup of fibrous reinforcing material in a first zone of a mould, wherein the composition of the resin mixture varies as the infusion process progresses;

[0063] FIGS. 3a to 3c show the resin mixture infusing the layup of fibrous reinforcing material in a second zone of the mould, wherein the composition of the resin mixture varies as the infusion process progresses;

[0064] FIGS. 4a to 4c show the resin mixture infusing the layup of fibrous reinforcing material in a third zone of the mould, wherein the composition of the resin mixture varies as the infusion process progresses; and

[0065] FIG. 5 shows a curing stage in the method for making a wind turbine component wherein the resin-infused layup in each zone is cured to form the wind turbine component.

DETAILED DESCRIPTION

[0066] The diagram in FIG. 1 schematically represents apparatus 10 for making a wind turbine component. The apparatus 10 comprises a mould 12. In this example the wind turbine component is a shell of a wind turbine blade. As such, the mould 12 is concave in transverse cross section. The mould 12 supports a layup 14 of fibrous reinforcing material, which may comprise reinforcing fibres such as reinforcing glass fibres. The mould 12 may comprise a substantially rigid main mould part on which the layup 14 is supported. In some examples, the mould 12 may additionally comprise a second mould part (not shown) which is arranged over the layup 14. As such, the layup 14 may be sandwiched between the main mould part and a second mould part. In some examples, the second mould part may be a vacuum film.

[0067] Referring still to FIG. 1, the apparatus 10 further comprises a supply of resin 16, such as epoxy resin for example. The apparatus 10 also includes a supply of hardener 20. The supply of hardener 20 in this example comprises a first hardener 20a and a second hardener 20b. The apparatus 10 further comprises a resin mixing and supply system 22 configured to mix the resin 16 with the first and/or second hardener 20a, 20b to create a resin mixture 24 (shown in FIGS. 2a to 5). The second hardener 20b may be faster than the first hardener 20a, i.e. the second hardener 20b may be more reactive than the first hardener 20a.

[0068] The apparatus 10 comprises a control system 26 configured to vary the relative proportions of the first and second hardener 20a, 20b in the resin mixture 24. The control system 26 is configured to control the speed of the hardener 20 by varying the relative proportions of the first and second hardeners 20a, 20b in the resin mixture 24. As such, the apparatus 10 facilitates control of the cure time and/or open time of the resin mixture 24 by varying the relative proportions of the first and second hardener 20a, 20b in the resin mix 24. For example, mixing the second hardener 20b with the resin 16 may create a resin mixture 24 having a faster cure time and/or open time than a resin mixture 24 comprising only resin 16 and the first hardener 20a.

[0069] In some examples, the apparatus 10 comprises a hardener metering system 28 as shown in FIG. 1. The hardener metering system 28 is preferably arranged to mix the first and second hardener 20a, 20b according to a mix ratio determined by the control system 26. As such, the control system 26 may control the speed of the hardener 20 and/or cure rate of the resin mixture 24 by controlling the mix ratio in the hardener metering system 28. The hardener metering system 28 is configured to supply a defined quantity of the mixed hardener 20 to the resin mixing and supply system 22.

[0070] The resin mixing and supply system 22 is preferably configured to supply the resin mixture 24 to the layup of fibrous reinforcing material 14 in an infusion process that will be described in more detail later with reference to the remaining figures. To supply the resin mixture 24 to the layup 14, the apparatus 10 may further comprise a plurality of resin inlets 30.

[0071] It will be appreciated that the apparatus 10 is only represented schematically in the diagrams in FIGS. 1 to 5. As such it will be understood that, in practice, the apparatus 10 may comprise any number of resin inlets 30. For example, preferably the mould 12 comprises resin inlets 30 on the right side and the left side of the mould 12. Resin inlets 30 are not shown on the left of the mould 12 in the figures solely to simplify the representations in the figures. Further, in practice, the resin inlets 30 are preferably arranged above the layup 14. For example, the resin inlets 30 may be provided in a second mould part, such as a vacuum film (not shown), arranged on top of the layup 14.

[0072] The mould 12 may comprise a plurality of mould zones 32a-c. Each of the resin inlets 30 may be associated with one of the mould zones 32. In the example shown in the figures, the mould 12 comprises three adjacent zones 32a-c and three corresponding resin inlets 30a-c. The resin inlets 30a-c may each comprise a corresponding inlet valve 34a-c configured to permit or cut off supply of the resin mixture 24 to the layup 14 through the corresponding resin inlet 30.

[0073] The control system 26 is configured to control the speed of the hardener 20 based upon one or more process parameters of the infusion process. As shown in FIG. 1, the apparatus 10 may therefore further comprise sensors for determining process parameters of the infusion process. For example, the apparatus may comprise temperature sensors 36 to measure the temperature of the mould 12. The apparatus 10 may further comprise temperature sensors 38 arranged to measure the temperature of the layup 14. The layup temperature sensors 38 may be provided on, or in, the vacuum film, if used.

[0074] Advantageously, the apparatus 10 may additionally comprise visual sensing means 40 such as a camera arranged above the mould 12. The camera 40 may be a visible light camera to monitor the position of the resin mixture flow front 42 (shown in FIGS. 2a to 5) during the infusion process. In some examples, the apparatus 10 may additionally or alternatively comprise an infra-red camera. The infra-red camera may be configured to facilitate monitoring of one or both of the temperature and/or flow front position 42 of the resin mixture 24 during the infusion process in some advantageous examples.

[0075] In some examples, the apparatus 10 may comprise heating elements 44 configured to heat the mould 12 and/or to help cure the resin-infused layup 14. The heating elements 44 are preferably arranged in, or beneath, the mould 12 to provide heat to the layup 14. As shown in FIG. 1, in some examples the apparatus 10 may comprise separate heating elements 44a-c corresponding to each mould zone 32a-c. The heating elements 44 are preferably independently controllable, such that each heating element 44 can be activated or deactivated in isolation.

[0076] The apparatus 10 facilitates faster infusion and curing of the resin mixture 24 by controlling the speed of the hardener 20 when manufacturing a wind turbine component. As will be described in more detail with reference to the remaining figures, the speed of the hardener 20 is controlled in accordance with the method of the invention by varying the relative proportions of the first and second hardeners 20a, 20b in the resin mixture 24 during the course of the infusion process in dependence upon one or more process parameters.

[0077] One example of a method of manufacturing a wind turbine component, such as a wind turbine blade, using the apparatus 10 described above will now be described with reference to the remaining figures.

[0078] The method initially involves arranging a layup 14 of fibrous reinforcing material on the mould 12. The layup 14 supported in the mould 12 is then infused with the resin mixture 24. As shown in FIG. 2a, the layup 14 in the first mould zone 32a is infused with resin mixture 24 supplied through the first resin inlet 30a. The resin mixture 24 supplied to the layup 14 comprises a mixture of resin 16 and one or more hardeners 20. An initial mix ratio of the first and second hardeners 20a, 20b is determined based upon one or more process parameters. For example, the initial mix ratio may be determined based upon feedback signals provided to the control system 26 by the mould temperature sensors 36 and/or the layup temperature sensors 38. At the start of the infusion process the resin 16 is preferably mixed predominantly or exclusively with the first hardener 20a. As such, the cure time of the resin mixture 24 may be relatively long in an initial stage of the infusion.

[0079] As more resin mixture 24 infuses into the layup 14, the flow front 42 progresses away from the first resin inlet 30a as shown in FIG. 2b. The position of the flow front 42 is monitored, for example by the infra-red camera 40 and/or visible light camera and/or layup temperature sensors 38. As the infusion process progresses, the speed of the hardener 20 is controlled by varying the relative proportions of the first and second hardeners 20a, 20b in the resin mixture 24. The control system 26 may determine a second mix ratio of the hardeners 20a, 20b based upon process parameters such as elapsed time since the start of infusion process and/or position of the resin mixture flow front 42 and/or resin temperature, for example. As the flow front 42 advances towards the second mould zone 32b, the speed of the hardener 20 may be increased by increasing the proportion of the second hardener 20b in the resin mixture 24.

[0080] The control system 26 may determine a third mix ratio of the hardeners 20a, 20b as the flow front 42 progresses further still from the first resin inlet 30a as shown in FIG. 2c. The third mix ratio is preferably determined to increase the speed of the hardener 20 further still. As the flow front 42 approaches the second resin inlet 30b, the resin mixture 24 supplied through the first resin inlet 30a may comprise resin 16 mixed predominantly or exclusively with the second (faster) hardener 20b. The speed of the hardener 20 may therefore be increased as the flow front 42 progresses away from the first resin inlet 30a and towards the second resin inlet 30b.

[0081] When the layup 14 arranged in the first mould zone 32a is fully infused, i.e. when the resin mixture flow front 42 reaches the portion of the layup 14 arranged in the second mould zone 32b, the method may involve curing, or starting to cure, the resin mixture 24 in the first mould zone 32a. For example, the resin mixture 24 may be cured by applying heat to the first mould zone 32a using a first heating element 44a. The resin mixture 24 infused in the layup 14 in the first mould zone 32a may be cured whilst resin mixture 24 is simultaneously supplied to the second mould zone 32b as shown in FIG. 3a.

[0082] Preferably, when the resin mixture flow front 42 reaches the second mould zone 32b, the resin mixture 24 is supplied to the layup 14 through the second resin inlet 30b. As such, the second resin inlet 30b may be opened when the resin mixture flow front 42 reaches the second mould zone 32b. In some examples, as shown in FIG. 3a, the first resin inlet 30a may be closed when the second resin inlet 30b is opened. Closing and opening the resin inlets 30 is synonymous with closing and opening valves 34 in the resin supply system which permit or cut off supply of the resin mixture 24 to the layup 14 through the corresponding resin inlet 30.

[0083] Preferably, the resin inlets 30 and/or valves 34 in the resin supply system are controlled by the control system 26. As such, the resin inlets 30 and/or valves 34 are preferably automatically controlled based upon process parameters fed back to the control system 26 from the sensors and/or camera(s) 40. The second resin inlet 30b may therefore be opened, and the first resin inlet 30a may be closed, when one or more of the visual sensing means 40 or layup temperature sensors 38 detect that the resin mixture flow front 42 has reached the second mould zone 32b.

[0084] When the resin mixture flow front 42 reaches the second zone 32b, the speed of the hardener 20 may be reduced by reducing the proportion of the second hardener 20b in the resin mixture 24. The mix ratio of first and second hardeners 20a, 20b is preferably determined based upon one or more process parameters. The resin mixture 24 supplied to the second mould zone 32b through the second resin inlet 30b preferably comprises resin 16 mixed predominantly or exclusively with the first hardener 20a. Accordingly, the hardener speed may be relatively slow upon commencing supply to the second zone 32b.

[0085] FIGS. 3b and 3c show further stages in the infusion process where the resin mixture flow front 42 progresses away from the second resin inlet 30b. As more resin mixture 24 infuses the layup 14 in the second mould zone 32b, the flow front 42 moves towards the layup 14 in the third mould zone 32c. As the flow front 42 advances towards the third mould zone 32c, the proportion of the second hardener 20b in the resin mixture 24 may be increased, thereby increasing the speed of the hardener 20. As such, the cure time of the resin mixture 24 being supplied to the second mould zone 32b may be shortened, i.e. get faster, as the flow front 42 progresses towards the third mould zone 32c. As the flow front 42 approaches the third resin inlet 30c, the resin mixture 24 being supplied through the second resin inlet 30b may comprise resin 16 mixed predominantly or exclusively with the second (faster) hardener 20b. The speed of the hardener 20 may therefore be increased as the flow front 42 progresses away from the second resin inlet 30b and towards the third resin inlet 30c.

[0086] FIGS. 4a to 4c show further stages in the infusion process where the resin mixture 24 is supplied to the layup 14 in the third mould zone 32c. Whilst the resin mixture 24 is supplied to the third mould zone 32c, the method may involve curing or partially curing the resin mixture 24 infused in the layup 14 in the second mould zone 32b. For example, the resin mixture 24 in the second mould zone 32b may be cured by applying heat to the second mould zone 32b using a second heating element 44b.

[0087] The resin mixture 24 may be supplied to the layup 14 in the third mould zone 32c through the third resin inlet 30c. In some examples, as shown in FIG. 4a, the second resin inlet 30b may be closed when the third resin inlet 30c is opened. When the resin mixture flow front 42 reaches the third mould zone 32c, the speed of the hardener 20 in the resin mixture 24 may be reduced. For example, the proportion of the second hardener 20b in the resin mixture 24 may be reduced. Preferably, the resin mixture 24 initially supplied to the third mould zone 32c through the third resin inlet 30b comprises a mixture of resin 16 and predominantly or exclusively the first hardener 20a.

[0088] The resin mixture flow front 42 progresses through the layup 14 in the third mould zone 32c and away from the third resin inlet 30c. As the infusion process progresses in the third mould zone 32c, the speed of the hardener 20 in the resin mixture 24 may be increased. For example, based on signals input to the control system 26 from the temperature sensors 36, 38 and/or cameras 40 monitoring the progress of the flow front 42, the control system 26 may increase the proportion of the second hardener 20b in the resin mixture 24. As the flow front 42 approaches the edge of the layup 14, and the infusion process nears completion, the resin mixture 24 supplied through the third resin inlet 30c may comprise a mixture of resin 16 and predominantly or exclusively the second hardener 20b.

[0089] Following completion of the infusion process, i.e. when the layup 14 in each of the mould zones 32a-c is thoroughly infused with resin mixture 24 as shown in FIG. 5, the heating elements 44 are preferably all set to cure the resin-infused layup 14.

[0090] Each production run is preferably recorded and analysed by an artificial intelligence system, such as a machine-learning system or a deep-learning system for example. The artificial intelligence system is preferably configured to receive feedback signals from the camera(s) 40 and/or any sensors comprised in the apparatus 10. For example, the artificial intelligence system may be integrated with the control system 26. In preferred examples, the artificial intelligence system receives data inputs from the sensors and/or cameras 40 and/or process logs of the infusion process to self-optimise the resin infusion and curing process. For example, optimising the infusion process may involve optimising settings such as vacuum pressure, mould temperature, resin supply pressure, resin mixture flow rate, resin temperature, hardener selection, hardener mix ratio, resin mixture curing temperatures, resin mixture cure rate, resin inlet opening and closing conditions and resin inlet control sequences for example. As such, the manufacturing process can be continuously optimised with each production run using the above-described method and apparatus 10.

[0091] The manufacturing method described above is preferably a substantially automated process. For example, the infusion process may be controlled by an artificial intelligence system configured to receive feedback from one or more cameras 40 and/or sensors 36, 38 of the apparatus 10, and based on said feedback, to control one or more process parameters of the infusion and curing process. For example, following manual arrangement of the fibrous reinforcing material in the mould 12, and arrangement of a second mould part if used, substantially the whole infusion and curing process may be automated and completed without further human input. The control system 26, preferably controlled by an artificial intelligence system, may control process parameters such as vacuum pressure, initial resin temperature, mould temperature, resin supply pressure, resin mixture flow rate, hardener mix ratio, resin inlet control sequences (opening and closing) and heating element control for example.

[0092] In the examples described herein with reference to the accompanying figures, the hardener 20 supplied to the resin mixing and supply system 22 is pre-mixed, i.e. the hardener 20 supplied to the resin mixing and supply system 22 comprises relative proportions of the first and/or second hardener 20a, 20b in accordance with the mix ratio determined by the control system 26. However, in some examples, the method may comprise separately providing specified amounts of the first and/or second hardener 20a, 20b to the resin mixing and supply system 22 in accordance with the mix ratio determined by the control system 26. As such, the first and second hardener 20a, 20b may be mixed together simultaneously with mixing the first and/or second hardener 20a, 20b with the resin 16 to create the resin mixture 24.

[0093] In the examples described above, the supply of hardener 20 comprises at least a first and second hardener 20a, 20b. However, in some examples, the method may comprise providing one or more further hardeners in addition to the first and second hardener 20a, 20b. The method may therefore comprise mixing the resin 16 with one or more of the first, second or additional hardeners to create the resin mixture 24.

[0094] Many modifications may be made to the examples described above without departing from the scope of the present invention as defined in the accompanying claims. It will be appreciated that features described in relation to each of the examples above may be readily combined with features described with reference to any other examples described herein without departing from the scope of the invention as defined by the following claims.