Understanding the Wind Turbine Braking System and Replacement Brake Pads

In the United States, an average of 3,000 wind turbines are built and installed annually. Since 1980 the total is now over 70,800 turbines. That is a lot of towers, nacelles, and blades standing tall across the country.

Critical to their safe operation is the wind turbine braking system.

Over a turbine’s 20-year lifespan, the brakes can perform between 500 and 1,000 emergency stops. Therefore, replacement brake pads and brake maintenance are essential to a wind turbine’s uptime.

This article discusses different braking methods and where to get replacement brake pads.

Wind Turbine Braking Applications

Two elements to consider with wind turbine braking systems are the speed of the wind turbines (low and high-speed) and the use of mechanical or aerodynamic forces.

Low-Speed Braking

Lower speed systems have different needs compared to high-speed turbines. They comprise a disc, or braking track, and brake pads. Hydraulic clamps and calipers around the braking disc create friction to slow and stop the blades.

High-Speed Braking

High-speed systems engage the generator and apply torque to the gearbox. This reduces the output power and slows the turbine. The higher the number of teeth and the larger the diameter of the brakes, the better the braking performance.

Aerodynamic Braking

Aerodynamic braking happens when the blades are turned 90 degrees to the wind to remove resistance on the blades. The wind turbine brake controller will help the turbine stop smoothly.

Mechanical Braking

Mechanical braking supports the aerodynamic braking. It also slows the turbine during adverse weather and ensures the nacelle remains stable during maintenance.

Types of Wind Turbine Braking Systems

The braking systems to stop the blades from spinning, or the nacelle from turning, encounter different loads and forces, requiring a variety of designs.

Yaw Brakes

Yaw brakes are a caliper system controlled with hydraulics. They lock the nacelle into or out of the wind by acting on the yaw ring or mounted onto the non-driving end of the yaw motor.

Models with side mounts are for light and medium-duty applications, while a base mounted caliper is best for heavy-duty applications.

Rotor Brakes

Rotor brakes withstand the high torque levels generated by the wind turbine’s gearbox. They act on the main rotor shaft using hydraulic, spring-applied calipers. With their position between the gearbox and generator, rotor brakes handle the emergency stops during dangerous weather.

Controlled by the wind turbine brake controller, rotor brakes offer braking power ranges from 100N to 1MN, depending on the brake model and turbine size.

Where to Get Replacement Brake Pads

The one constant among the variety of braking systems is brake pads. Kor-Pak offers a full range of replacement brake pads for wind turbine systems and can cater to OEM and aftermarket parts across the wind turbine industry.

Contact us today to learn how our industrial brake and friction materials experts can help you.


Posted in Wind Turbines.