Methods and devices for accessing a drive train of a wind turbine with elastic coupling, wind turbine and methods

A drive train for a wind turbine comprising:

• a rotor shaft configured to be driven by a rotor about a main axis;
• a support structure including a bearing housing surrounding at least one bearing and supporting the rotor shaft for rotation about the main axis, thereby constraining other movements of the rotor shaft;
• a gearbox input shaft and a gearbox housing supporting the gearbox input shaft for rotation about the main axis while constraining other movements of the gearbox input shaft;
• and
• an elastic coupling that couples the gearbox input shaft to the rotor shaft, the elastic coupling comprising a first coupling part rigidly connected with the rotor shaft, a second coupling part rigidly connected with the gearbox input shaft, and
• elastic elements positioned between the first and the second coupling part, thereby constituting a single joint between the rotor shaft and the gearbox input shaft,
• wherein the rotor shaft and the gearbox input shaft are mounted with a preset eccentricity of longitudinal main axes of the rotor shaft and the gearbox input shaft, such that the longitudinal axis of the rotor shaft and the longitudinal axis of the gearbox input shaft are mounted eccentrically to each other in order to minimize any eccentricity or offset resulting from weight and/or loads and/or torque during operation,
• wherein the elastic coupling comprises a sensor device to monitor a condition of the elastic coupling, wherein the sensor device is a rotational sensor device comprising rotational sensor targets and rotational sensor units, and wherein the first coupling part and the second coupling part of the elastic coupling each comprise a rotational sensor target being attached to a respective circumference of the first and second coupling part to determine a at least one of
• a rotational speed of the rotor shaft and/or the gearbox;
• a phase shift between the rotational position of the rotor shaft and the rotational position of the gearbox based on the output of the sensor;
• and
• a load torque of the elastic elements.