drive question

[ThomasJ]

I was wondering if anyone has used hydraulics to power their generators. What I had envisioned was a single large windmill turning a hi volume hydraulic pump with hydraulic lines reaching down to ground level to a hi pressure motor that would turn several, ground based generators. I was hoping that this would work to crank up the revs with a bypass valve to prevent overspeeding the gens in high winds. Any thoughts or input would be greatly appreciated.

[oztules]

It will be reasonably difficult to implement as a maintenance free system but would work. (not my first choice)

It does lend itself to using variable pitch swashplate drive for the genny, to achieve a torque converter... and that would give you an MPPT built in. (just control the swash angle as you would by computer excited coil as with an excavator pump drive system).

From a practical perspective, the normal way is simpler to implement, with less losses, but the wind is  free and if the hydraulic lines and components are too, then there is nothing stopping you really.... as it is really a normal system, with all the hydraulics thrown on top.

You could also bring the shaft power down to ground level via right angle drive  gearbox and long drive shaft, rather than hydraulic line, as they do with the Turbex http://www.turbex.co.za/Documents/Generator.html

So the hydraulic system will work, but not the easiest way to get power from the wind, even if you bring the power down the tower as per Turbex. They do drive a pump (water), but even they use a generator direct from the drive shaft at ground level

The acid test is.... does anyone do this hydraulic angle commercially? and if not why not?

Perhaps there are just better ways.



............................oztules

[ThomasJ]

thanks for the input. The hydraulics are indeed free except for the lines but I figured that this setup would be a lot simpler to maintain with just a couple of bearings and the single pump up there then to set up multiple towers and generators to get the same output and with the generators at ground level, it would be a one stop situation to make sure that they were operating properly. The other advantage that I figured would be that there would be less parasitic friction and inertia losses due to weight, multiple bearings and a transmission

[thirteen]

How are you going to handle the expansion of the oil? There may no be much.  Are you in an area that has real cold weather which in some cases might cause problems with the oil flow? Would putting a valve on the return side so it could be shut off let you use that as a way to stop the blades and lock the pump up so when you leave you could stop it and then restart it when you got back. It sounds workable. Best of luck.

[ThomasJ]

I would be using a reservoir to compensate for expansion and the temperature here rarely gets to 0F so I figured that a lightweight oil would work. I like the idea of a shut off valve to lock the blade. I hadn't considered that, thanks for the idea.

[thirteen]

depending on the pump it may not lock it up. A call to the manufacturer of the pump might be the way to go.

[ThomasJ]

not 100% sure which pump i will be using. I have a few choices ie an old fork lift, several choices from several abandoned tugs and barges or if I want to go huge, the pump from an old excavator that I found abandoned in the woods close to work. It's all on an abandoned homestead and it's free for the picking No doubt, whichever one that I pick, it's going to need a rebuild but that should still be cheaper then buying brand new units