Yaw System Introduction

Wind turbines include a yaw bearing that allows the rotor nacelle assembly to rotate into the wind allowing power capture across all directions at a geographic site. To enable yaw rotation, the yaw bearing system comprises a series of electrical rotary actuator motors that each drive a pinion wheel that meshes with the yaw bearing gear ring. When power producing the wind turbine yaw bearing is often held in a fixed position using a series of brakes.

Bladed provides a versatile yaw modelling option and an adaptable control interface:

• The yaw model is a detailed representation of a yaw bearing, gearbox and actuation. A gearbox is used to represent the gear ratio that exists between the yaw bearing and actuator motors. This means the scaling of torque and yaw motor inertia with gearbox ratio will be handled directly by the multibody structural dynamics, including bearing friction and stiction. In addition, two actuator load banks can be included to simulate pre-loading of the yaw motors.

• The output of the yaw system includes yaw bearing loads and yaw actuation kinematics.

Note

The yaw angle is set to 0 degrees and locked for Steady Operational Loads calculation.