Abstract:
A wind turbine generator includes: a nacelle provided with a plurality of modules; a controller provided in a first module out of the plurality of modules; a first device provided in a second module out of the plurality of modules. The controller and the first device are connected with a device-side connection mechanism and a controller-side connection mechanism to allow electrical communications between the controller and the first device. The device-side connection mechanism includes: a first connection element; and a first multicore cable including a plurality of signal lines with one end connected to the controller and the other end connected to the first connection element. The device-side connection mechanism provides an electrical connection between the first connection element and the first device.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This is a continuation application of International Application No. PCT/JP2010/054464, filed on Mar. 16, 2010. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a wind turbine generator and more specifically to signal line wiring in the nacelle of the wind turbine generator. 
         [0004]    2. Description of the Related Art 
         [0005]    A wind turbine generator is an aggregate of many electrical/electronic devices and mechanical devices, and achieves efficient power generation through their coordinated operations. For example, a pitch control system is provided in a rotor head, and a gear box, a generator, an electric power converting device, a yaw control system, and other auxiliary systems (a hydraulic system, a lubrication system and so on) are provided in a nacelle. These devices are controlled by a controller (typically, a nacelle control board provided in the nacelle). The controller detects statuses of the respective devices and the wind condition by using measuring devices and sensors provided in various positions of the wind turbine generator, and optimally controls the electric/electronic devices and the mechanical devices within the wind turbine generator, in response to the detected statuses and wind condition. 
         [0006]    In a wind turbine generator, in which a large number of electric/electronic and mechanical devices operate cooperatively, a large number of signal lines are used for transmitting electrical signals. The respective devices of the wind turbine generator need to be connected with signal lines which supply control signals for control of the respective devices. Moreover, the respective measuring devices and sensors need to be connected with signal lines for transmitting detection signals to the controller. Thus, a large number of signal lines are wired in the nacelle of the wind turbine generator. In association therewith, U.S. Patent Application Publication No. 2008/0293260 A1 discloses a connector structure for flowing a great current in a wind turbine generator. U.S. Pat. No. 5,365,424 discloses a bus structure for transmitting great electric power in a wind turbine generator. 
         [0007]    One problem is difficulty in the wiring of the signal lines in the nacelle. An increase in the number of signal lines necessitates a long time for the wiring of the signal lines and may also cause increased wiring mistakes. With such background, there is a need of providing a technique that makes it easy to wire a large number of signal lines in the nacelle of the wind turbine generator. 
       SUMMARY OF THE INVENTION 
       [0008]    Therefore, an objective of the present invention is to provide a technique that makes it easy to wire a large number of signal lines in a nacelle of a wind turbine generator. 
         [0009]    In an aspect of the present invention, a wind turbine generator includes: a nacelle provided with a plurality of modules; a controller provided in a first module out of the plurality of modules; a first device provided in a second module out of the plurality of modules. The controller and the first device are connected with a device-side connection mechanism and a controller-side connection mechanism to allow electrical communications between the controller and the first device. The controller-side connection mechanism includes: a first connection element; and a first multicore cable including a plurality of signal lines with one end connected to the controller and the other end connected to the first connection element. The device-side connection mechanism provides an electrical connection between the first connection element and the first device. 
         [0010]    In one embodiment, the device-side connection mechanism includes: a second connection element; and a second multicore cable including a plurality of signal lines with one end connected to the second connection element and the other end connected to the first device. 
         [0011]    The wind turbine generator may further include a second device provided in one of the plurality of modules (other than the first module), and the controller and the second device may be connected with: a third connection element; a third multicore cable including a plurality of signal lines with one end connected to the controller and the other end connected to the third connection element; a fourth connection element connected to the third connection element; and a fourth multicore cable including a plurality of signal lines with one end connected to the second device and the other end connected to the fourth connection element. In this case, it is preferable that the third connection element is structured to be physically non-connectable to the second connection element and that the fourth connection element is structured to be physically non-connectable to the first connection element. 
         [0012]    The device-side connection mechanism may include: a signal relay board provided with a receptacle connected to the first connection element; and a plurality of signal lines with one end connected to the signal relay board and the other end connected to the first device. 
         [0013]    In a case where the first device includes a plurality of sensors, it is preferable that the plurality of signal lines of the device-side connection mechanism include a plurality of grounding lines respectively connected to the plurality of sensors and that the plurality of grounding lines are commonly connected to the ground by the signal relay board. 
         [0014]    In a case where the plurality of signal lines of the first multicore cable include a first power supply line and the first device includes a plurality of sensors, it is preferable that the plurality of signal lines of the device-side connection mechanism include a plurality of second power supply lines respectively connected to the plurality of sensors and that the plurality of second power supply lines are commonly connected to the first power supply line with the signal relay board. 
         [0015]    In one embodiment, the second module is a front module installed with a gear box connected to a wind turbine rotor, and the first module is a rear module installed with a generator connected to the gear box. In this case, it is preferable that the plurality of modules further includes a turning module including at least part of a yaw turning system that turns the nacelle in an azimuthal direction, that the turning module is provided on a top of a tower of the wind turbine generator, and that the front module and the rear module are provided on the turning module. 
         [0016]    The present invention makes it easy to wire a large number of signal lines in the nacelle of the wind turbine generator. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a side view showing the structure of a wind turbine generator in one embodiment of the present invention; 
           [0018]      FIG. 2  is a perspective view showing the inner structure of a nacelle in one embodiment; 
           [0019]      FIG. 3A  is a block diagram showing cable wiring inside the nacelle in one embodiment; 
           [0020]      FIG. 3B  is a block diagram showing the cable wiring inside the nacelle in one embodiment; 
           [0021]      FIG. 4  is a block diagram showing details of the cable wiring inside the nacelle in one embodiment; 
           [0022]      FIG. 5  is a conceptual diagram showing a preferred structure of a signal relay board in one embodiment; 
           [0023]      FIG. 6A  is a diagram showing the structure of a jack of a connector in one embodiment; 
           [0024]      FIG. 6B  is a diagram showing a structure of a plug of the connector in one embodiment; 
           [0025]      FIG. 6C  is a diagram showing a structure of a jack of a connector in one embodiment; and 
           [0026]      FIG. 6D  is a diagram showing a structure of a plug of the connector in one embodiment. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0027]      FIG. 1  is a side view showing the structure of a wind turbine generator  1  in one embodiment of the present invention. The wind turbine generator  1  is provided with: a tower  2  provided upright on a base  6 ; a nacelle  3  provided on the top of the tower  2 ; a rotor head  4  rotatably attached to the nacelle  3 ; and wind turbine blades  5  attached to the rotor head  4 . The rotor head  4  and the wind turbine blades  5  constitute a wind turbine rotor. Upon rotation of the wind turbine rotor by wind power, the wind turbine generator  1  generates electric power and supplies the electric power to the utility grid connected to the wind turbine generator  1 . 
         [0028]    In this embodiment, the nacelle  3  includes three modules: a front module  7 , a rear module  8 , and a turning module  9 . The turning module  9  is provided on the tower  2 , and the front module  7  and the rear module  8  are provided on the turning module  9 . The front module  7  is located adjacently to the rotor head  4 , while the rear module  8  is located away from the rotor head  4 . The division of the nacelle  3  into a plurality of modules effectively facilitates transportation of the nacelle  3  to the construction site where the wind turbine generator  1  is to be built. 
         [0029]      FIG. 2  is a perspective view showing the inner structure of the nacelle  3  in one embodiment.  FIGS. 3A and 3B  are block diagrams showing cable wiring in the nacelle  3 . Here,  FIG. 3A  illustrates the cable wiring in the front module  7  and the rear module  8 , and  FIG. 3B  illustrates the cable wiring in the turning module  9 . 
         [0030]    The front module  7  is installed with a gear box  11  and a gear box accessory  21 . The rear module  8  is installed with a generator  12 , a boost-up transformer  13 , a power control board  14 , a nacelle control board  15 , and a generator accessory  22 . The turning module  9  is provided with a cylindrical body  10 . The turning module  9  includes a yaw motor  23  and a lubrication system accessory  24  provided outside of the cylindrical body  10  and includes a hydraulic system accessory  25  provided inside of the cylindrical body  10 . 
         [0031]    In the following, a brief description is given of each of the aforementioned devices. The gear box  11  rotates the rotor of the generator  12  at a higher speed than that of the rotation of the rotor head  4 . The gear box accessory  21  is a peripheral device that assists the operation of the gear box  21 , including a supply system that supplies lubricant to the gear box  11 , for example. The generator  12  is driven by the wind turbine rotor and the gear box  11  to generate electric power. The generator accessory  22  is a peripheral device that assists the operation of the generator  22 . The boost-up transformer  13  boosts up the voltage of the electric power generated by the generator  12  in accordance with the voltage of the utility grid (the utility voltage). The power control board  14  monitors the electric power exchange between the generator  12  and the utility grid. The nacelle control board  15  is a controller that collectively controls the respective devices provided in the nacelle. The yaw motor  23  is a driving device that turns the nacelle  3  in the azimuthal direction; the yaw motor  23  is a component of a yaw turning system. The lubrication system accessory  24  is one of the components of the lubrication system that supplies lubricant to main shaft bearings (not shown) rotatably supporting the main shaft (not shown) connected to the rotor head  4 . The hydraulic system accessory  25  is one of the components of a hydraulic system that supplies operating fluid to a pitch control mechanism controlling the pitch angle of the wind turbine blades  5 . 
         [0032]    Sensors are attached to the respective devices in the nacelle  3  for measuring the statuses thereof. In this embodiment, a group of sensors  26  are attached to the generator  12 , and groups of sensors  27  and  28  are attached to the gear box  11 . Further, a group of sensors  29  are attached to the hydraulic system accessory  25 , and a group of sensors  30  are attached to the lubrication system accessory  24 . 
         [0033]    Schematically, signal lines are wired in the wind turbine generator  1  of this embodiment as described below. Multicore cables attached to the devices and sensors installed in the rear module  8 , which is provided with the nacelle control board  15 , are directly connected to a terminal block provided on the nacelle control board  15  by using plugs. The multicore cables are each provided with a plurality of signal lines therethrough. Connecting one multicore cable to the nacelle control board  15  allows a plurality of signal lines to be simultaneously connected to the nacelle control board  15 . 
         [0034]    For the devices and sensors provided in the modules other than the rear module  8 , on the other hand, connectors or signal relay boards are used in addition to multicore cables to wire signal lines. Specifically, for devices provided in modules other than the rear module  8 , the multicore cables connected to the devices are connected to multicore cables connected to the nacelle control board  15  with connectors to thereby wire a desired number of signal lines. On the other hand, for the sensors provided in the modules other than the rear module  8 , the signal lines of the sensors are connected to signal relay boards provided in the respective modules and the signal relay boards are connected to the nacelle control board  15  with multicore cables to thereby wire a desired number of signal lines. In either case, use of a multicore cable permits a plurality of signal lines to be simultaneously connected to the nacelle control board  15 . In the following, a description is given of the cable wiring inside the nacelle  3 , more specifically. 
         [0035]    Referring to  FIG. 3A , the generator accessory  22  provided in the rear module  8  is connected to the nacelle control board  15  with a multicore cable  61 . More specifically, as shown in  FIG. 4 , one end of the multicore cable  61  is connected to the generator accessory  22 , the other end of the multicore cable  61  is connected to a plug  63 , and the plug  63  is connected to a terminal block  15   a  of the nacelle control board  15 . On the other hand, referring back to  FIG. 3A , the sensors  26  provided in the generator  12  are connected to the nacelle control board  15  with a multicore cable  62 . More specifically, as shown in  FIG. 4 , one end of the multicore cable  62  is connected to the sensors  26 , the other end of the multicore cable  62  is connected to a plug  67 , and the plug  67  is connected to a terminal block  15   b  of the nacelle control board  15 . 
         [0036]    On the other hand, as shown in  FIG. 3A , the gear box accessory  21  provided in the front module  7  is connected to the nacelle control board  15  with multicore cables  31  and  32  and a connector  33 . More specifically, the multicore cable  31  is connected to the gear box accessory  21  in the front module  7 , the multicore cable  32  is connected to the nacelle control board  15  in the rear module  8 , and the multicore cables  31  and  32  are connected together with the connector  33 . As shown in  FIG. 4 , the connector  33  is provided with a jack  33   a  connected to the multicore cable  31  and a plug  33   b  connected to the multicore cable  32 , and the jack  33   a  and the plug  33   b  are connected together to thereby connect the multicore cables  31  and  32 . It should be noted that, in this embodiment, the terms “plug” and “jack” of the connector only identify two separate parts composing the connector  33 ; it would be obvious that the jack may be connected to the multicore cable  31  and the plug may be connected to the multicore cable  32 . 
         [0037]    On the other hand, the sensors  27  and  28  attached to the gear box  11  are connected to the nacelle control board  15  with a signal line bundle  44 , a signal relay board  41 , and a multicore cable  46  (see  FIG. 3A ). Conceptually illustrated in  FIG. 4  is the cable routing between the sensors  27  and the nacelle control board  15 . It should be that, in  FIG. 4 , the group of sensors  27  includes three sensors  27   a,    27   b,  and  27   c,  but the number of sensors  27  is not limited to three. The signal relay board  41  is provided in the front module  7 , and includes a receptacle  41   a  and a terminal block  41   b.  On the other hand, the signal line bundle  44  is provided with signal lines respectively connected to the sensors  27   a,    27   b,  and  27   c.  The signal lines of the signal line bundle  44  are respectively connected to terminals provided on the terminal block  41   b.  In addition, the signal line bundle  44  is provided with grounding lines  44   a,    44   b,  and  44   c  respectively connected to the sensors  27   a,    27   b,  and  27   c.  The grounding lines  44   a,    44   b,  and  44   c  are commonly connected to the casing of the signal relay board  41 , that is, the ground. Other lines of the signal line bundle  44  are connected to the receptacle  41   a  via the terminal block  41   b.  One end of the multicore cable  46  is connected to a plug  47 , and the other end of the multicore cable  46  is connected to a plug  65 . The plug  47  is connected to the receptacle  41   a  and the plug  65  is connected to the terminal block  15   b  of the nacelle control board  15 , whereby the sensors  27  are electrically connected to the nacelle control board  15 . Here, the plug  47  is so configured as to connect the grounding lines out of the signal lines provided through the multicore cable  46  to the casing of the signal relay board  41 . This achieves connecting the grounding lines of the multicore cable  46  to the ground. Although not shown in  FIG. 4 , the sensors  28  are also connected to the nacelle control board  15  via the multicore cable  46  in the same manner. In  FIG. 3A , a relay box  45  is inserted in the signal line bundle  44  that connects together the sensors  28  and the signal relay board  41 , but the presence of the relay box  45  is essentially not important. 
         [0038]    Here, as shown in  FIG. 5 , a power supply line (line supplied with the power supply voltage) of the multicore cable  46  may also be shared by the sensors  27   a,    27   b,  and  27   c.  Specifically, the signal line bundle  44  is provided with power supply lines  44   d,    44   e,  and  44   f  respectively connected to the sensors  27   a,    27   b,  and  27   c.  On the other hand, a power supply line  46   a  connected to the power supply line of the multicore cable  46  is drawn out of the receptacle  41   a  to the terminal block  41   b,  and the power supply lines  44   d,    44   e,  and  44   f,  which are respectively connected to the sensors  27   a,    27   b,  and  27   c,  are commonly connected to the power supply line  46   a.  This configuration effectively reduces the number of lines included in the multicore cable  46 . 
         [0039]    The hydraulic system accessory  25 , which is provided inside the cylindrical body  10  of the turning module  9 , is connected to the nacelle control board  15  with multicore cables  34  and  35  and a connector  36  (see  FIGS. 3A and 3B ). Here, the multicore cable  34  I routed through the turning module  9  and the front module  7 , and the multicore cable  35  is provided in the rear module  8  and connected to the nacelle control board  15 . The multicore cables  34  and  35  are connected together with the connector  36 . 
         [0040]    Similarly, the yaw motor  23 , which is provided outside the cylindrical body  10  of the turning module  9 , is connected to the nacelle control board  15  with multicore cables  37  and  38 . Specifically, the multicore cable  37  is connected to the yaw motor  23  in the turning module  9 , the multicore cable  38  is connected to the nacelle control board  15  in the rear module  8 , and the multicore cables  37  and  38  are connected together with a connector  39 . Although the connector  39  is shown as being located inside the turning module  9  in  FIG. 3B , the connector  39  may be located in the rear module  8 . 
         [0041]    Further, the sensors  29 , which are provided inside the cylindrical body  10  of the turning module  9 , are connected to the nacelle control board  15  with a signal line bundle  48 , a signal relay board  42 , and a multicore cable  49 . The signal line bundle  48  is connected to the signal relay board  42  in the turning module  9 . Here, the grounding lines of the signal line bundle  48  are connected to the casing of the signal relay board  42 , that is, the ground, and other lines of the signal line bundle  48  are electrically connected to a receptacle of the signal relay board  42 . A plug  50  is provided at one end of the multicore cable  49  and connected to the receptacle of the signal relay board  42 . The other end of the multicore cable  49  is connected to the nacelle control board  15 . With this configuration, the sensors  29  are electrically connected to the nacelle control board  15 . 
         [0042]    Similarly, the sensors  30 , which are provided outside the cylindrical body  10  of the turning module  9 , are connected to the nacelle control board  15  with a signal line bundle  51 , a signal relay board  43 , and a multicore cable  52 . The signal line bundle  51  is connected to the signal relay board  43  in the turning module  9 . Here, the grounding lines of the signal line bundle  51  are connected to the casing of the signal relay board  43 , that is, the ground, and other lines of the signal line bundle  51  are electrically connected to a receptacle of the signal relay board  43 . A plug  53  is provided at one end of the multicore cable  52  has one end, and connected to the receptacle of the signal relay board  43 . The other end of the multicore cable  52  is connected to the nacelle control board  15 . With such configuration, the sensors  30  are electrically connected to the nacelle control board  15 . 
         [0043]    An advantage of such cable wiring is remarkable reduction in the labor required for wiring the signal lines at the construction site where the wind turbine generator  1  is to be built. That is, in a factory where the front module  7 , the rear module  8 , and the turning module  9  are manufactured, connections are made other than those listed below:
       (1) the connection between the multicore cables  31  and  32  with the connector  33 ;   (2) the connection of the plug  47  of the multicore cable  46  to the signal relay board  41 ;   (3) the connection between the multicore cables  34  and  35  with the connector  36 ;   (4) the connection of the plug  50  of the multicore cable  49  to the signal relay board  42 ;   (5) the connection between the multicore cables  37  and  38  with the connector  39 ; and   (6) the connection of the plug  53  of the multicore cable  51  to the signal relay board  43 .       
 
         [0050]    In this state, the front module  7 , the rear module  8 , and the turning module  9  are transported to the construction site where the wind turbine generator  1  is to be built. After the front module  7 , the rear module  8 , and the turning module  9  are combined to form the nacelle  3  on the tower  2 , the connections (1) to (6) described above are made. With such procedure, the cable wiring can be easily achieved at the construction site where the wind turbine generator  1  is built. 
         [0051]    The fact that reduced labor is required for the cable wiring leads to prevention of wiring mistakes. Here, in order to prevent the wiring mistakes even more effectively, it is preferable that the connectors  33 ,  36 , and  39  and the plugs  47 ,  50 , and  53  are so configured as to physically avoid the wiring mistakes. That is, a configuration such that the plugs, the jacks, and the receptacles used in the wind turbine generator  1  can be physically connected together only in the correct combinations allows avoiding the wiring mistakes more effectively. 
         [0052]      FIGS. 6A to 6D  show examples of configurations of the connectors  33  and  36  for preventing the wiring mistakes. Here,  FIGS. 6A and 6B  respectively show a structure of the jack  33   a  and the plug  33   b  of the connector  33 , and  FIGS. 6C and 6D  respectively show a structure of a jack  36   a  and a plug  36   b  of the connector  36 . As shown in  FIG. 6A , the jack  33   a  is provided with a jack casing  74  and a socket insert  75 . On the other hand, as shown in  FIG. 6B , the plug  33   b  is provided with a plug casing  71 , a plug insert  72 , and pins  73 . A plurality of protrusions are provided on the outer surface of the plug insert  72 . Between the jack casing  74  and the socket insert  75  of the jack  33   a,  a groove  76  for accommodating the plug insert  72  is provided. The groove  76  has a shape corresponding to the shape of the plug insert  72 . Further, pin holes  77  for accommodating the pins  73  are provided for the socket insert  75 . In  FIGS. 6A and 6B , symbols P 1  and P 2  indicate virtual reference planes used for showing the positions of the pins  73  and the pin holes  77 . 
         [0053]    Referring to  FIGS. 6C and 6D , the jack  36   a  and the plug  36   b  of the connector  36  have shapes similar to those of the jack  33   a  and the plug  33   b  of the connector  33 . Specifically, as shown in  FIG. 6C , the jack  36   a  is provided with a jack casing  84  and a socket insert  85 . On the other hand, the plug  36   b  is provided with a plug casing  81 , a plug insert  82 , and pins  83  as shown in  FIG. 6D . A plurality of projections are provided on the outer surface of the plug insert  82 . Between the jack casing  84  and the socket insert  85  of the jack  36   a,  a groove  86  for accommodating the plug insert  82  is provided. The groove  86  has a shape corresponding to the shape of the plug insert  82 . Further, at the socket insert  85 , pin holes  88  for accommodating the pins  83  are provided. In  FIGS. 6C and 6B , symbols P 1  and P 2  indicate virtual reference planes used for showing the positions of the pins  83  and the pin holes  87 . 
         [0054]    Here, the protrusions provided on the outer surfaces of the plug inserts  72  and  82  are at the same positions with respect to the reference planes P 1  and P 2 , but the positions of the pins  83  and the pin holes  87  with respect to the reference planes P 1  and P 2  are different from the positions of the pins  73  and the pin holes  77 . With such structures of the connectors  33  and  36 , the plugs and the jacks of the connectors  33  and  36  can be connected together only in the correct combinations. Configurations such that connections can be achieved only in correct combinations can be provided in the same manner for other plugs, jacks, and receptacles. This is preferable in terms of preventing the wiring mistakes in the wind turbine generator  1 .