LIDAR
LIDAR (light detection, imaging and ranging) is a laser Doppler anemometer system by which laser beams mounted on the turbine measure the wind field ahead of the turbine. This information can be passed to the controller, to implement a feed-forward control system. The instruments collect data by emitting light waves from transducers according to some pre-determined scanning pattern. Particles suspended in the air cause backscatter of the emitted waves. The Doppler shift in the frequency of the backscattered light is used to determine the wind speed along the direction of the LIDAR beam, at a particular focal point. This information can be logged in the control system and used to enhance the control strategy to provide load reduction.
The LIDAR definition can be accessed via Specify->Control Systems…->LIDAR. The LIDAR definition allows the specification of
multiple beams that take velocity measurements at intervals and pass the
data to the User-Defined Controller. All the options in the LIDAR screen
only affect the LIDAR definition and the information passed through to
the external controller, and do not affect any other environmental or
structural definitions within Bladed.
When setting up a simulation with LIDAR the user will have to:
- Select an appropriate mounting location and scanning pattern such that during dynamic simulation the Beam Direction can be updated and a Line of Sight wind speed calculated. The appropriate settings can be set either through the User Interface or in a User-Defined Controller.
- Select appropriate Wind Modelling settings particularly for Turbulent and Transient wind conditions.
- Write custom control logic in a User-Defined Controller that uses the Line of Sight to implement feed-forward control for the benefit of load reduction.
Last updated 30-08-2024