System and method for preventing catastrophic damage in drivetrain of a wind turbine

A drivetrain assembly of a wind turbine, the drivetrain assembly comprising:

• a main shaft for coupling to a rotor of the wind turbine;
• a gearbox coupled to the main shaft;
• a generator coupled to the gearbox;
• and,
• a controller for controlling operation of the wind turbine, the controller comprises at least one processor, the at least one processor configured to perform a plurality of operations, the plurality of operations comprising:
• receiving a speed measurement of the generator of the drivetrain;
• determining an electrical torque of a generator of the drivetrain of the wind turbine;
• estimating a mechanical torque of the rotor as a function of at least one of the electrical torque and the speed measurement of the generator;
• comparing the estimated mechanical torque to an implausible torque threshold wherein torque values above the implausible torque threshold are indicative of a failure of the drivetrain of the wind turbine;
• and,
• implementing a control action for the wind turbine when the estimated mechanical torque exceeds the implausible torque threshold, wherein the control action comprises shutting down the wind turbine.

A method for preventing catastrophic damage in a drivetrain of a wind turbine, the drivetrain having, at least, a rotor and a generator, the method comprising:

• determining an electrical torque of the generator of the drivetrain;
• receiving, from one or more sensors, a speed measurement of the generator;
• determining, via a controller, a mechanical torque of a rotor of the wind turbine, or an acceleration of the generator required to accelerate or decelerate inertia of the drivetrain, to maintain the speed measurement based, at least in part, on the determined electrical torque of the generator of the drivetrain or the speed measurement of the generator of the drivetrain;
• and,
• when the mechanical torque and/or the acceleration exceed an implausible threshold, implementing a control action for the wind turbine, wherein the control action comprises shutting down the wind turbine.