Gearbox Failures in Wind Turbines

[ragtoplvr]

When they erect the turbines, they spend some time with the rotor locked. Locked seldom means zero movement, could a slight rocking back and forth cause surface failure in those spots.

The blades must have some creep, meaning that when they are first spun there will be some out of balance. This could overload the bearing and make it fail.



Rod

 

[Kestas]

Static damage from micromovement when standing still can and will do damage to bearing raceways. It is called "false brinelling."

The classic case for false brinelling is with automotive wheel bearings on new cars that are shipped across the country.

 

[DriveHard]

There was recently a Drenchearo that passed thru windmill country of Iowa and Illinois. Anyone know how the windmills did or did not survive.

Those members in the area might watch in the coming months and see if a lot of turbines are shut down or under repair as it seems reasonable that design limits were approached if not exceeded. 100MPH wind with rain, hail, farmers roofs, etc.


Rod

They shut down and pitch the blades to minimize drag in high winds. I have several large wind farms near me very close to the epicenter of the Derecho, and I did not see a single turbine failure, most were back to running automatically later that afternoon.

 

[MolaKule]

When they erect the turbines, they spend some time with the rotor locked. Locked seldom means zero movement, could a slight rocking back and forth cause surface failure in those spots.

The only possible movement would be due to clearances between gear teeth and that is in thousandths of an inch.

The blades must have some creep, meaning that when they are first spun there will be some out of balance. This could overload the bearing and make it fail. Rod

The blade/hub system is well balanced.

Much research is still ongoing and there has NOT been a "smoking gun" identified.

My view is that any solution(s) forthcoming will be a change in both the bearing metallurgy AND a change in the lubricant's formulation, especially in a formulation that reduces the amount of total hydrogen in the lubricant.

 

[Silver]

You know those things cause cancer right?

 

[blingo]

The smoking guns?

 

[4WD]

Passed through a new wind farm near me yesterday

 

[Surestick]

Passed through a new wind farm near me yesterday View attachment 30983

Did you get cancer? ;-)

 

[ollie]

The mode of failure is simple. It's clearly outlined in part 3 of the "Observations on the Basic Problems". I would be more interested in the cause and solution to fix and prevent further failures in the future.

I'm of the opinion of the cause being a transient load failure. The frequency and power of intermittent gusts of wind are near impossible to predict. Over time because of that the stress, bearing failure is inevitable.

My solution would be some kind of liquid filled damping device mounted near the gearbox to help take away enough of the vibration to extend the life of the unit. I would imagine a large one on the turntable and smaller one added to the existing shaft be effective.

Unfortunately it is going to take a team of engineers and bean counters working closely together to find a cost effective solution. And we all know how hard it is to make a team like that to work.....

 

[zzyzzx]

When I saw the thread title, I assumed that the same people who designed CVT's and DCT's were designing these wind turbine gearboxes.

 

[ollie]

When I saw the thread title, I assumed that the same people who designed CVT's and DCT's were designing these wind turbine gearboxes.

 

[4WD]

Did you get cancer? ;-)

When I passed them midday they had a cancer called “no wind carcinoma“ …
in the evening the breeze had them turning again 🌬

 

[ollie]

Those wind turbines and solar farms are an amazing site to see. The mind blower is seeing a single half prop hanging over a 53' flatbed!!

 

[4WD]

Those wind turbines and solar farms are an amazing site to see. The mind blower is seeing a single half prop hanging over a 53' flatbed!!

 

[ollie]

And we wonder about gearbox failures?

 

[OVERKILL]

Those wind turbines and solar farms are an amazing site to see. The mind blower is seeing a single half prop hanging over a 53' flatbed!!

They aren't so amazing when your electricity prices triple paying their subsidy and they generate near zero useful electricity for your grid (wind specifically). At least solar, at limited penetration levels, can depress daytime peaking requirements.

 

[ollie]

Yes that would suck for sure!!

 

[OVERKILL]

Yes that would suck for sure!!

A telling graph, this was Ontario's wind output last summer during our highest demand months. The fleet is ~5,000MW.

 

[Exhaustgases]

Just like all modern day engineering, too much computer time and not much engineering time. Bad choice of bearing type for the application.
Simple stuff.

 

[blingo]

Definitely all suddenly looks much simpler now on page two. On the first page it still was a mystery that somehow grew up for sixty years or so in pure research...