AeroTorque Torsional Dampers
PT Tech’s experience in Wind goes back to the early 1990’s as we developed custom OE solutions for difficult drivetrain issues in wind turbines. Beginning in 2011, PT Tech began doing field research into the unusual transient loads that occur in these drivetrains. Wind turbines are different than most other systems. The bedplates/frames are highly flexible compared to most industrial drivetrains and are mounted on towers. Additionally, transient loads can be driven by either end of the system, variable winds and gusts and the grid/controls itself.
Field data was gathered to show the frequency and magnitude of these transient loads and load reversals, often within as quickly as 400 milliseconds. Tens of thousands of events have been recorded and analyzed.
The results of this work led to the development of the WindTC torsional control, which can reduce loading caused by torsional reversals by 40% and reduce oscillations in the drivetrain by 50-70%. For the first time, your gearbox and bearings can be protected from these damaging loads. This is available as a standalone solution or mounted to a Lovejoy coupling as a package solution!
The WindTC™ is the only torsional control on the market that treats forward and reverse torques differently. When a drivetrain’s inertias get out of sync (which field work has shown occurs much more often than commonly believed), the WindTC can quickly damp the reversal and limit the damaging effects. Stock torque limiters cannot react below their high forward setting, thus allow these shock loads to go through the gearbox and the rest of the drivetrain. Most importantly, the WindTC minimizes the significant torque reversal impact at the end of a hard stop. This final impact load occurs AFTER THE TURBINE HAS STOPPED ROTATING and is likely significant driver in damage to turbine components.
With the WindTC, the transients are damped before they can allow the drivetrain to torsionally unload. As a torsional “shock absorber” in the system, an asymmetric approach can react almost instantly to reduce the transients. The wind-up of the system can be reduced, thus preventing high damaging loads. The addition of an asymmetric device in existing turbines is a major step in extending the life of drive components.
The WindTC™ is the only torque limiter that is effective in mitigating the damaging loads on the wind turbine gearbox from harsh negative torque. These loads are particularly bad for gearbox bearings in the turbine as the sudden shock loads do not allow time for the rollers to reposition as they accelerate into the load zone. This can cause skidding and edge loading of the rollers and can cause a damaging impact load on the inner race. With a Wind TC in the system, reversal loading is reduced to a significantly lower level, allowing for gears, rollers and races to be protected when they are at the highest risk.
Easily mounted on the shaft between the generator and the turbine motor, using the existing spacer shaft, the WindTC™ significantly cuts transient torque spikes.
“We inspected these (gearboxes) last June at their 3 year mark. The boxes showed no signs of wear whatsoever. Other than gear mesh marks, they looked brand new…If the limiters extend the life even 6 months, we come out even. If they add a year to the life, I doubled my money by installing them. I believe the limiters add 12 to 24 months of life to the boxes (this is a VERY conservative estimate)” – Site Manager
WindTM – Torque Monitoring Service
Prove it to yourself. Learn what’s going on in your Gearbox!
Have you ever measured the current torque on your wind turbine’s drive train for both FORWARD AND REVERSE TORQUE? If you don’t know the loads that are entering your gearbox, how do you know it is protected or getting damaged?
The WindTM is a service provided by AeroTorque to monitor and record the torque loads in your turbine. During typical trials, nominal torque data and transient torque event data is recorded for a 3-6 week time period before the equipment is removed.
Mounts on Main shaft
Stores 100 worst events in forward and reverse
Accurate high-resolution data