WIND TURBINE AND METHOD FOR MONITORING THE GAP LENGTH BETWEEN A ROTOR AND A STATOR OF THE WIND TURBINE GENERATOR

摘要

Wind turbine (1) comprising a generator section (6) with a generator rotor (9) and a generator stator (25). A first air gap (26) is defined between a first surface (23) of the generator rotor and the stator (25), and magnets and electro conductive windings are provided at opposite sides of the first air gap (26) to create a magnetic field over the first air gap during operation. The wind turbine (1) comprises distance measurement means (34) arranged to measure the radial length of a second air gap (33) defined between a second surface (36) of the generator rotor and a stationary part (35) of the generator section (6). The second air gap (33) is located at a radial distance from the first air gap (26) at a position where there is no interference of a magnetic field generated by the magnets over the first air gap (26), and the length of the second air gap (33) corresponds directly to the length of the first air gap (26). This enables accurate measurement and monitoring of the air gap length. A method for monitoring the gap length between a rotor and a stator of a wind turbine generator is also disclosed.