Systems and methods for determining the angular position of a wind turbine rotor

A system for determining an angular position of a wind turbine rotor, the system comprising:

• at least one accelerometer operable to measure tangential acceleration and radial acceleration at one or more measurement positions on the rotor;
• a shaft encoder operable to measure rotor speed;
• one or more processors operable to:
• determine rotational tangential acceleration of the rotor at the one or more measurement positions based at least in part on the change of rotor speed over time;
• determine rotor rotational radial acceleration based at least in part on the rotor speed;
• adjust the measured tangential acceleration with the determined rotational tangential acceleration;
• adjust the measured radial acceleration with the determined rotational radial acceleration;
• and,
• determine an angular position of the rotor based at least on the adjusted tangential acceleration and the adjusted radial acceleration.

A wind turbine comprising:

• a rotor comprising one or more blades;
• at least one shaft in communication with the rotor;
• a shaft encoder in communication with the shaft;
• a wind turbine control system comprising:
• at least one accelerometer mounted to the rotor;
• and,
• one or more processors;
• wherein:
• the at least one accelerometer is operable to measure tangential acceleration and radial acceleration at one or more measurement positions on the rotor;
• the shaft encoder is operable to measure the speed of the rotor;
• the one or more processors are operable to:
• determine rotational tangential acceleration of the rotor at the one or more measurement positions based at least in part on the change of rotor speed over time;
• determine rotational radial acceleration based at least in part on the rotor speed;
• adjust the measured tangential acceleration with the determined rotational tangential acceleration;
• adjust the measured radial acceleration with the determined rotational radial acceleration;
• and,
• determine an angular position of the rotor based at least on the adjusted tangential acceleration and the adjusted radial acceleration.