Abrasion sensing device, wind turbine generation apparatus including the same, and abrasion sensing method

An abrasion sensing device sensing abrasion of one of a gear and a bearing of a gearbox provided in a wind turbine generation apparatus,

• said wind turbine generation apparatus including
• a blade converting wind force into rotary force,
• a main shaft receiving said rotary force from said blade,
• said gearbox speeding up rotation of said main shaft,
• a power generator connected to an output shaft of said gearbox, and
• a nacelle storing said main shaft, said gearbox and said power generator, and being rotatably supported at an upper part of a support,
• said abrasion sensing device comprising:
• a braking device for holding the output shaft of said gearbox in a non-rotating state;
• a rotation angle sensor for detecting a rotation angle of said main shaft
• a control unit for reversing, by changing a wind receiving state by said blade, the direction of the rotary force exerted on said main shaft by wind force;
• and
• a determination unit determining presence/absence of abrasion of one of said gear and said bearing by comparing a first detected value of said rotation angle sensor before reversing the direction of said rotary force by said control unit and a second detected value of said rotation angle sensor after reversing the direction of said rotary force by said control unit while said braking device is being operated.