摘要 |
When it is determined that a blade is rotating (YES in S10), a control device operates a braking device (S20), and acquires a rotation angle (first rotation angle) from a rotation angle sensor (S30). Then, the control device reverses a nacelle (S40) and acquires again a rotation angle (second rotation angle) from the rotation angle sensor (S50). Then, the control device determines whether or not the difference between the first rotation angle and the second rotation angle is greater than a threshold value (S60). When it is determined that the rotation angle difference is greater than the threshold value (YES in S60), the control device determines that a gear or a bearing of a gearbox is worn out (S75). |