The Basics of a Windturbine

A wind turbine turns the energy of wind into electricity using the aerodynamic force from its rotor blades. This is similar to the way an airplane wing or helicopter rotor blade works.

The generator component, which is approximately 34 per cent of the wind turbine cost, includes an electrical generator, control electronics, and most likely a gearbox (e.g., planetary gearbox, adjustable-speed drive or continuously variable transmission).

Blades

Wind turbine blades are made of a variety of materials. Most of them are composites, with glass fibers and carbon fibers as the main reinforcement. They are also often reinforced with steel, copper wire, and a combination of materials like balsa wood and foams.

The matrices used in wind blade composites (or reinforced polymers) have to meet the high stiffness, strength and durability requirements for wind turbines. Typically, thermosets (epoxies, polyesters, vinylesthers) or thermoplastics are used as matrices for these composites.

Most blades, especially long ones, are produced in a process called resin infusion. This method consists of injecting resin into the mold cavity under pressure and then curing it with heat. In some cases, a vacuum is also used. This is known as Vacuum Assisted Resin Transfer Molding (VARTM).

Rotor

A wind turbine’s rotor, which is the area of the turbine that consists of the blades and the hub, spins as the wind blows on it. The rotor turns into a shaft and the turning shaft spins a generator, which makes electricity.

Most turbines have three blades that are made of fiberglass or carbon-fiber-reinforced plastics. The blades have airfoils that make them able to change their shape as the wind changes direction.

As the wind strikes one side of a blade, a pocket of low-pressure air forms on that side, which creates lift. The force of the lift is stronger than the force of the wind’s drag on the front side of a blade, which causes the rotor to turn.

Because of the weight of a turbine’s components, it must be carefully controlled to keep its rated rotation speed within its limits. The rated rotation speed is also important for controlling the capacity factor, which measures how much power a turbine produces over a given time period.

Tower

The tower is the main structural base of a wind turbine, and supports both the rotor blades and the nacelle module. There are several different types of towers, including tubular steel, concrete, lattice, and hybrid.

Generally, larger turbines have taller towers than smaller ones. This is because higher towers can capture more wind energy than lower towers do.

In addition to this, a taller tower allows for more air flow in front of the turbines’ rotors, which can reduce noise emissions. Lastly, towers help prevent the rotors from collapsing during strong winds.

Some large wind turbines use tubular steel for their towers, which is manufactured in sections that can be bolted together on site. This saves materials and helps reduce costs.

Controls

The controls of a windturbine help reduce loads on turbine components and capture more wind energy to produce more electricity. They also ensure safe operation and optimize power output.

Several control strategies can be used to manage turbine functionality throughout the power curve, including pitch and generator speed control. Pitch and generator speed control can increase energy extraction, improve power quality, and regulate generator speed for efficient power regulation at rated power.

There are a variety of control techniques, each with its own advantages and disadvantages. You should choose the control method that best suits your needs based on cost and turbine technology.

NREL researchers are working to develop new control methodologies that maximize energy extraction and reduce load on wind turbine components. They are testing advanced controls algorithms on the National Wind Technology Center’s Controls Advanced Research Turbines (CARTs) and other advanced research wind turbines.