This application discloses a method, device, and apparatus for maintaining a wind turbine generator plant, which relates to the field of wind power generation. The method includes determining a failure of the wind turbine generator plant when the wind turbine generator plant enters a shutdown maintenance mode; determining a maintenance wind speed corresponding to the failure; adjusting one of blades of the wind turbine generator plant to reach a predetermined azimuth angle and lock an impeller of the wind turbine generator plant to maintain the wind turbine generator plant in a case where the failure belongs to a first type of failure and a real-time wind speed obtained is less than or equal to the maintenance wind speed corresponding to the failure, the first type of failure comprising a failure that requires to lock the impeller for maintenance and the predetermined azimuth angle being a different integral multiple of 30?.

The present disclosure relates to methods for rotating a locked rotor of a wind turbine in case of an imbalance in a rotor plane of the rotor, comprising: rotating the rotor using an inching tool to apply torque on a drive train of the wind turbine to reduce the imbalance in the rotor plane; and removing a locking pin from a locking disc operatively connected to the rotor after reducing the imbalance in the rotor plane. The methods further comprise estimating a direction of a torque load due to the imbalance in the rotor plane using one or more sensors, and impeding the inching tool to apply torque on the drive train of the wind turbine in the estimated direction of the torque load due to the imbalance. The present disclosure further relates to inching tools and to methods for installing rotor blades on a hub of a wind turbine.

A method of disengaging a rotor-lock of a wind turbine, the rotor comprising one or more blades, which due to the gravitational pull, generates a rotor torque which is opposed by a rotor-lock counter-torque from the rotor-lock, the method comprising: a) determining a direction of the rotor torque with a sensor system; b) applying a rotor-drive counter-torque to the rotor with a rotor-drive system, wherein the rotor-drive counter-torque acts to oppose the determined rotor torque and causes the rotor-lock counter-torque to reduce; c) during or after the application of the rotor-drive counter-torque, disengaging the rotor-lock mechanism; wherein the step of determining a direction of the rotor torque comprises applying a torque restriction to the rotor-drive based on the determined direction of the rotor torque, the torque restriction preventing the application of torque to the rotor by the rotor-drive system in the same direction as the rotor torque.

The present disclosure relates to methods for rotating a locked rotor of a wind turbine in case of an imbalance in a rotor plane of the rotor, comprising: rotating the rotor using an inching tool to apply torque on a drive train of the wind turbine to reduce the imbalance in the rotor plane; and removing a locking pin from a locking disc operatively connected to the rotor after reducing the imbalance in the rotor plane. The methods further comprise estimating a direction of a torque load due to the imbalance in the rotor plane using one or more sensors, and impeding the inching tool to apply torque on the drive train of the wind turbine in the estimated direction of the torque load due to the imbalance. The present disclosure further relates to inching tools and to methods for installing rotor blades on a hub of a wind turbine.

This application discloses a method, device, and apparatus for maintaining a wind turbine generator plant, which relates to the field of wind power generation. The method includes determining a failure of the wind turbine generator plant when the wind turbine generator plant enters a shutdown maintenance mode; determining a maintenance wind speed corresponding to the failure; adjusting one of blades of the wind turbine generator plant to reach a predetermined azimuth angle and lock an impeller of the wind turbine generator plant to maintain the wind turbine generator plant in a case where the failure belongs to a first type of failure and a real-time wind speed obtained is less than or equal to the maintenance wind speed corresponding to the failure, the first type of failure comprising a failure that requires to lock the impeller for maintenance and the predetermined azimuth angle being a different integral multiple of 30.

A method of disengaging a rotor-lock of a wind turbine, the rotor comprising one or more blades, which due to the gravitational pull, generates a rotor torque which is opposed by a rotor-lock counter-torque from the rotor-lock, the method comprising: a) determining a direction of the rotor torque with a sensor system; b) applying a rotor-drive counter-torque to the rotor with a rotor-drive system, wherein the rotor-drive counter-torque acts to oppose the determined rotor torque and causes the rotor-lock counter-torque to reduce; c) during or after the application of the rotor-drive counter-torque, disengaging the rotor-lock mechanism; wherein the step of determining a direction of the rotor torque comprises applying a torque restriction to the rotor-drive based on the determined direction of the rotor torque, the torque restriction preventing the application of torque to the rotor by the rotor-drive system in the same direction as the rotor torque.