WES30 Nacelle

The nacelle is the box on top of the tower that contains equipment such as gearbox, generator, yaw-system and control system. The base plate of the nacelle is made of hot dip galvanized steel. The yaw bearing connects the nacelle to the tower and makes that it can be positioned

Gearbox

The FLENDER gearbox increases, in two stages with a ratio of 1:20, the rotor speed to the working range of the generator (1200 to 2400 rpm). The rotor is directly mounted to the low speed shaft of the gearbox. The generator is connected to the high-speed shaft of the gearbox with a flexible coupling. When the turbine is in its parking position (120 degrees out of the wind), the wind will be at the back side of the blades. A blocking device in the gearbox prevents the rotor from turning the wrong way (anti-clockwise). The rotor will come to a stand-still.
During maintenance it is required that the rotor is blocked. After bringing the turbine in its parking position a pin will be put in manually to block the high-speed shaft of the gearbox.

Generator

The generator is a 6-pole a-synchronous generator especially manufactured for wind turbine applications by ABB in Finland. Since an a-synchronous generator is brushless, it is virtually maintenance free. The generator is totally enclosed and cooled by a fan, directly mounted on the shaft. The nominal power of the generator is 250 kW. The reactive current, needed to allow the generator to build up a magnetic field, is obtained from a capacitor package.
The choice for a a-synchronous generator is key in the WES30 design. Fluctuations in wind speed are absorbed by rotor and generator frequency. Fluctuations in wind speed do not cause fluctuations in loads on blades, gearbox or tower. This is the main reason why the WES30 has a long live expectancy and needs little maintenance. The combination of an a-synchronous generator and IGBT technology allows the WES30 to deliver electricity in weak or small grids.

Yaw system

The yaw-system turns the nacelle in or out of the wind. The IPC in the control cabinet collects wind data from wind vane and anemometer and directs the nacelle through the yaw-system. In case of a grid failure the yaw-motor will be, through a capacitor bank, directly connected to the generator. As a result the turbine will yaw out of the wind to the parking position all by itself.

Sensors

Several sensors such as wind vane, anemometer, imbalance sensor, rotation counter and cable twist sensor are located in the nacelle and connected to IPC. Based on the information from these sensors the IPC will direct the turbine or stop it when needed.

Nacelle hood open.

Under the hood.

Nacelle.