A method of monitoring one or more blades of a rotor of a wind
turbine, the method comprising: obtaining bending information indicating bending of one or more of the blades; obtaining
pitch information indicating a
pitch angle of one or more of the blades; when
wind speed is below a rated
wind speed: operating the wind
turbine in a partial load mode in which
pitch angles of the blades are controlled to maximise power captured by the rotor; operating a first detection mode in which the bending information is analysed to determine whether a blade anomaly exists and generate a corresponding output, wherein the first detection mode coincides with the partial load mode over a first range of wind speeds; when
wind speed is above the rated wind speed: operating the wind
turbine in a full load mode in which the pitch angles of the blades are varied to capture a maximum allowed power with the rotor; and operating a second detection mode in which the pitch information is analysed to determine whether a blade anomaly exists and generate a corresponding output, wherein the second detection mode coincides with the full load mode over a second range of wind speeds.