Wind Power Technology and Wind Power Generation Principles

The principle of wind power generation is to use the wind to drive the blades of the windmill to rotate, and then increase the speed of rotation through the speed increaser to drive the generator to generate electricity. According to the current windmill technology, power generation can be started at a breeze speed (the degree of breeze) of about three meters per second.

The small wind power generation system is very efficient, but it is not only composed of a generator head, but a small system with certain technological content: wind turbine + charger + digital inverter.

A wind turbine consists of a nose, a swivel, an empennage, and blades. Every part is very important, and the functions of each part are: the blades are used to receive the wind force and convert it into electric energy through the nose, the empennage makes the blades always face the direction of the wind to obtain the maximum wind energy, and the swivel can make the nose rotate flexibly to achieve The function of the empennage to adjust the direction, the rotor of the nose is a permanent magnet, and the stator winding cuts the magnetic field lines to generate electric energy.

Nacelle: The nacelle contains the key equipment of the wind turbine, including the gearbox and generator. Maintenance personnel can enter the nacelle through the wind turbine tower. The left end of the nacelle is the wind turbine rotor, that is, the rotor blades and shaft.

Rotor blades: capture the wind and transmit it to the rotor shaft. On a modern 600-kilowatt wind turbine, each rotor blade measures about 20 meters in length and is designed much like an airplane wing.

Shaft: The rotor shaft is attached to the low speed shaft of the wind turbine.

Low speed shaft: The low speed shaft of the wind turbine connects the rotor shaft to the gearbox. On a modern 600 kW wind turbine, the rotor speed is fairly slow, around 19 to 30 revolutions per minute. There are conduits in the shaft for the hydraulic system to activate the operation of the aerodynamic brakes.

Gearbox: The left side of the gearbox is the low-speed shaft, which can increase the speed of the high-speed shaft to 50 times that of the low-speed shaft. High-speed shaft and its mechanical brake: The high-speed shaft runs at 1500 revolutions per minute and drives the generator. It is equipped with emergency mechanical brakes, which are used when the aerodynamic brakes fail, or when the wind turbine is being repaired.

Generators: Often referred to as induction motors or asynchronous generators. On modern wind turbines, the maximum electrical output is usually 500 to 1500 kilowatts. Yaw device: Turns the nacelle with the help of an electric motor so that the rotor is facing the wind. The yaw unit is operated by an electronic controller which senses the direction of the wind through a wind vane. The figure shows the wind turbine yaw. Typically, wind turbines only deflect a few degrees at a time as the wind changes its direction.

Electronic Controller: Contains a computer that constantly monitors the status of the wind turbine and controls the yaw device. To prevent any failure (ie, overheating of the gearbox or generator), the controller can automatically stop the wind turbine and call the wind turbine operator via a telephone modem.

Hydraulic system: used to reset the aerodynamic brake of the wind turbine.

Cooling element: Contains a fan to cool the generator. In addition, it contains an oil cooling element for cooling the oil inside the gearbox. Some wind turbines have water cooled generators.

Tower: The wind turbine tower contains the nacelle and rotor. Usually taller towers have an advantage because the higher the ground, the greater the wind speed. The tower height of a modern 600 kW wind turbine is 40 to 60 meters. It can be a tubular tower or a lattice tower. Tubular towers are safer for maintenance personnel as they can reach the top via an internal ladder. The advantage of a lattice tower is that it is less expensive.