‘ What Is Inside An Industrial Wind Turbine ‘
An overview of the layout of utility-class wind turbine generators – where are the major components, what do they do, and what differences can be found between models and size ranges. The content of this video shows and explains the set up starting with the tower, tower access, turbine equipment arrangement such as controller and transformer cabinetts and finally up to the nacelle and all its components and hub and rotor systems.
Below a high level overview of the components making up an industrial wind turbine with today’s technology:
- The Anemometer: Measures the wind speed and transmits wind speed data to the controller.
- The Blades: Most turbines have either two or three blades. Two or three turbine blades make up the rotor. Wind blowing over the blades causes the blades to “lift” and rotate.
- The Brake: A brake, which can be applied mechanically, electrically, or hydraulically to stop the rotor in emergencies. A brake is fitted which can be set when dangerously strong winds are approaching or when the turbine is taken down for maintenance.
- The Controller: Everything is controlled via an electronic controller which takes data inputs from an anemometer which measures the speed of the wind, and a wind vane which detects the direction of the wind. The controller also starts up the machine and shuts off the machine at too high wind speeds because the turbine might be damaged by the high winds.
- The Gear Box: Gears connect the low-speed shaft to the high-speed shaft and increase the rotational speeds from about 30 to 60 rotations per minute (rpm) to about 1000 to 1800 rpm, the rotational speed required by most generators to produce electricity. Basically, the gearbox accelerates the speed of rotation of the high-speed shaft to the levels necessary to generate high voltage electricity with the generator. The gear box is a costly (and heavy) part of the wind turbine and engineers are exploring “direct-drive” generators that operate at lower rotational speeds and don’t need gear boxes.
- The Generator: Usually an off-the-shelf induction generator that produces 60-cycle AC electricity.
- The Low-Speed Shaft: The rotor turns the low-speed shaft at about 30 to 60 rotations per minute. The low-speed shaft is rotated by the rotor which is spun by the wind
- The High-Speed Shaft: Drives the generator. The rotation from the low-speed shaft is passed onto the high-speed shaft
- The Nacelle: The nacelle sits atop the tower and contains the gear box, low- and high-speed shafts, generator, controller, and brake. Some nacelles are large enough for a helicopter to land on. The nacelle is the sealed unit at the top of the tower which automatically rotates to face into the wind with a yaw motor turning the yaw drive
- The Pitch: The pitch of each blade can be changed (i.e. the blade can be rotated) to increase efficiency in low winds and to decrease efficiency (to protect the wind turbine) in very strong winds. Blades are turned, or pitched, out of the wind to control the rotor speed and keep the rotor from turning in winds that are too high or too low to produce electricity.
- The Rotor: The blades and the hub together are called the rotor which is spun by the wind
- The Tower: Towers are made from tubular steel (shown here), concrete, or steel lattice. Because wind speed increases with height, taller towers enable turbines to capture more energy and generate more electricity.
- The Wind Vane: Measures wind direction and communicates with the yaw drive to orient the turbine properly with respect to the wind.
- The Yaw Drive: Upwind turbines face into the wind; the yaw drive is used to keep the rotor facing into the wind as the wind direction changes. Downwind turbines don’t require a yaw drive, the wind blows the rotor downwind.
- The Yaw Motor: Powers the yaw drive.