The wind turbine market has been slowly recovering since the 2008 global
financial crisis. While there was significant improvement in 2012 and 2013,
global wind power grew by a record 50+ GW in 2014. There are currently six
countries that have an installed wind capacity of more than 10,000 MW, with
China, the U.S. and Germany leading the world. The U.S. alone produces
enough wind energy to power more than 16 million homes.
Europe has been experiencing substantial growth in offshore wind capacity,
with 408 turbines added in 2014. This brings the cumulative total of installed
and grid-connected offshore turbines to 2,488 in 11 European countries.
The small wind and distributed wind segments of the market (turbines from
5 kW to 500 kW) are also growing. In the U.S., 40% of distributed wind
(power which is primarily consumed at the point of generation) is deployed in
residential applications, while agriculture accounts for 26% and
industrial/commercial uses 20%.
SUPERIOR ROTOR AND YAW BRAKING TECHNOLOGIES
As they meet the world’s growing demand for wind energy, global wind turbine
OEMs rely on Svendborg Brakes and Twiflex Limited for innovative hydraulic
caliper braking solutions. The braking systems control the speed of wind
turbine rotors as well as the 360 degree yaw rotation of the turbine’s nacelle as
it follows changing wind directions. These two Altra brands work closely with
major turbine OEMs as they develop new turbine models of various designs
and capacities, while improving efficiency, performance, and cost-effectiveness.
SVENDBORG BRAKES SUPPORT ALL TYPES AND SIZES
OF WIND TURBINES
Svendborg engineers have developed a series of
hydraulically-applied caliper brakes specifically for rotor
and yaw braking applications on direct drive, compact
drive and conventional wind turbines.
To meet the most common turbine OEM requests,
the brakes provide easy maintenance and friction pad
replacement. They also feature corrosion protection,
monitoring systems (on-off switch, pad wear monitor,
etc.), and special friction material designed and tested
to meet typical wind turbine rotational speed and heat
Newer, large turbines do not require full-scale,
high-speed rotor braking. The brakes are engaged to
bring a drivetrain that is operating at a reduced/idling
speed to a complete stop. Both rotor and yaw brakes
also provide holding functionality.
BSAK Series caliper brakes are preferred for rotor braking
duty where large pads are required for high thermal
dissipation during dynamic braking. Special versions of
Model BSAB 90 and BSAB 120 caliper brakes also
feature large pads but are designed for turbines where
space is limited.
A Svendborg Model BSAK 3000 caliper brake is shown mounted to a wind turbine rotor disc.
A minimum of four Model BSAB 90 or BSAB 120
hydraulically applied caliper brakes are typically utilized
on wind turbine yaw braking systems. These brakes
are designed to provide years of quiet, leak-free
performance. This is especially important for offshore
applications, but also a concern for rivers, lakes and
Extensive wind turbine application knowledge and
accumulated experience allows Svendborg engineers
to routinely modify these standard brake models
to fit unique customer turbine designs and specific
As part of their complete braking package solutions,
Svendborg has designed a variety of stand alone and
combined hydraulic power units for yaw brakes and
dynamic rotor brakes or rotor lock and roof hatch control
on compact drive and conventional wind turbines. All
units are built in-house to meet particular customer
TWIFLEX LIMITED PROVIDES PROVEN BRAKING
SYSTEMS FOR THE DISTRIBUTED WIND MARKET
Twiflex is recognized by OEMs as a high quality
manufacturer of rotor and yaw caliper brakes used
in small- to medium-sized wind turbines (typically
20-200 kW). The brakes provide both static and
dynamic stopping functionality.
Twiflex braking technologies are designed to meet
customer demands for compact size and low weight,
minimal maintenance, ease of installation and
Robust Twiflex VCS-FL and VKSD-FL spring-applied,
hydraulically-released models feature reduced axial
widths, which makes them ideal selections for both rotor
and yaw applications in smaller turbines.
The FL “floating” caliper configurations feature a single
spring module and reactive half to accommodate axial
movement of the shaft. These versions are consequently
highly tolerant of misalignment during installation. Large
pad versions are available to address particular heat
With the brake in the “parked off” position, disc spring
load and hydraulic pressure are zero, allowing pads to
be removed in safety. This feature also permits brake
installation without the need for hydraulic pressure.
The Twiflex team provides complete technical and
engineering support for all wind applications to ensure
proper brake selection and system configuration.
*Source: Global Wind Energy Council; www.gwec.net