1. Home
  2. Electronics Design
  3. Re: 11kw 240vac 60(ish) hz 1 cyl diesel Generator "problem"

Re: 11kw 240vac 60(ish) hz 1 cyl diesel Generator "problem"

Someone beat me to it but the first thing that came to mind when

>I read your post was a ferroresonant voltage regulator. The only >repairs I've had to make to such units was to replace the capacitor >or capacitors if the regulator has more than one. If you build your >own, I would suggest obtaining high quality caps or to have several >spares on hand. I found a company that manufacturers some >regulators but they only listed a max capacity of 2.5KW. A bit of >searching the surplus market could turn up parts or a whole unit >in your size because a new big one is quite expensive. Besides, >it's more fun to roll your own. > >
formatting link
$.htm

Yea, rolling my own is definetly something I enjoy :)

I had this crazy idea for "fixing" the frequency fluctuation.. Build a voltage regulator that would modulate the Rotor voltage in an attempt to fudge the zero crossing of the 60hz output. Not sure how doable it is, but I'm guessing the smartups is measure zero crossing to zero crossing to figure out frequency. If I can fudge the zero crossing times I might trick the Smartups to go online :)

Of course, it might be smarter and easier to fudge JUST the power going to the SmartUPS instead of fooling around with modulating the Rotor Voltage on the generator head..

I also found out yesterday that once the diesel warms up a little and the HVAC system stops running while the Fridge is off, the SmartUPS will come on-line again (Basicly, only when there is a very small - no load on the generator, which corresponds to very small frequency wobble)...

On another Wild Tangent (which would make a good Business Name, but I digress), I keep ponder how much mass I'd have to move inward on the Flywheel to keep the Flywheel angular velocity a constant between power strokes under a 10Kw load.. (Something like a centrifical govenor, but on steroids and if it ever came apart at speed, would be something interesting to observe from the safe side of a blast door window..)

--
Take Care,
James Lerch
http://lerch.no-ip.com/atm (My telescope construction,testing, and coating site)
http://lerch.no-ip.com/ChangFa_Gen (My 15KW generator project)

"Anything that can happen, will happen" -Stephen Pollock from:
"Particle Physics for Non-Physicists: A Tour of the Microcosmos"

" Press on: nothing in the world can take the place of perseverance.
Talent will not; nothing is more common than unsuccessful men with talent.
Genius will not; unrewarded genius is almost a proverb.
Education will not; the world is full of educated derelicts.
Persistence and determination alone are omnipotent. "
Reply to
James Lerch
Loading thread data ...

And the problem with using a VFD instead is....?

--
Many thanks,

Don Lancaster                          voice phone: (928)428-4073
Synergetics   3860 West First Street   Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml   email: don@tinaja.com

Please visit my GURU\'s LAIR web site at http://www.tinaja.com
Reply to
Don Lancaster

Something else tickled my brain and floated to the front. I was talking to a fellow who was having a problem with damage to his drive system on a rock crusher. The mechanical shock was breaking gears and couplings to the electric motor. I suggested a fluid coupling that was available at the local supply house. It's basically a self contained torque converter much like the one in the automatic transmission of an automobile that smooths out the power pulses from the engine. It may work for you. These couplings are available in many different sizes.

formatting link

formatting link

[8~{} Uncle Monster
Reply to
unclemon

LOL

THIS is why I love doing off the wall projects like this. I get to learn about sooo many cool things I didn't know existed :)

If I was smart and cheap, I could rig an old automotive transmision torque converter to do the job.. I wonder how the real product deals with heat disapation? Hmmm..

I like it on many levels! :)

Thanks

--
Take Care,
James Lerch
http://lerch.no-ip.com/atm (My telescope construction,testing, and coating site)
http://lerch.no-ip.com/ChangFa_Gen (My 15KW generator project)

"Anything that can happen, will happen" -Stephen Pollock from:
"Particle Physics for Non-Physicists: A Tour of the Microcosmos"

" Press on: nothing in the world can take the place of perseverance.
Talent will not; nothing is more common than unsuccessful men with talent.
Genius will not; unrewarded genius is almost a proverb.
Education will not; the world is full of educated derelicts.
Persistence and determination alone are omnipotent. "
Reply to
James Lerch

Well, it sort of falls into the AC -> DC -> AC category, and I doubt the SmartUPS would like it's power as an input. For instance, I know cascading SmartUPS isn't smart, or more to the point, it doens't work..

So far, the most direct solution is probably a 1hp induction motor spinning a large flywheel attached to a 2kw gen head. basicly a home brewed MG set..

Hmmm, this is interesting

formatting link

I didn't think that would work.... Only need 700watts or so to feed battery backups under normal conditions.

Hmmmm.... Could make for interesting experiments.

--
Take Care,
James Lerch
http://lerch.no-ip.com/atm (My telescope construction,testing, and coating site)
http://lerch.no-ip.com/ChangFa_Gen (My 15KW generator project)

"Anything that can happen, will happen" -Stephen Pollock from:
"Particle Physics for Non-Physicists: A Tour of the Microcosmos"

" Press on: nothing in the world can take the place of perseverance.
Talent will not; nothing is more common than unsuccessful men with talent.
Genius will not; unrewarded genius is almost a proverb.
Education will not; the world is full of educated derelicts.
Persistence and determination alone are omnipotent. "
Reply to
James Lerch

What you want is to keep it as simple as possible. Thats what me me think of the fluid coupling for smoothing out the mechanical power pulse problem. Those fluid couplings don't heat up like the torque converters in automobiles because they don't have a lot of slip designed in. Remember an automotive torque converter sits there churning away when you have your foot on the brake and the transmission in drive. If you use an automotive converter, try to find one with a low stall speed (ie less slip) of the type used in a small high mpg car. The torque converters designed for towing and racing have higher stall speeds (more slip) allowing a higher engine speed before the converter tightens up. Perhaps one out of a little Honda or Toyota would work.

[8~{} Uncle Monster
Reply to
unclemon

Do you mean you'd have some kind of servos on the flywheel itself that moves the weights like a skater's arms, within a quarter-cycle, to keep the speed constant?

But seriously, how about adding some weight to the existing flywheel? You could cast a big lead ring around it... ;-)

I think rotational momentum is kind of like inductance, but I'm sure I've got my terminology wrong and probably mixed units...

Good Luck! Rich

Reply to
Rich Grise

How about sort of an electrical equivelent:

If a synchonous motor is spinnging a heavy mass, it will naturally want to keep the frequency constant. If instead of a real synchonous motor, you used a wound rotor 3 phase motor in its place, you could drive the rotor field ahead and behind in phase to transfer more energy in and out of the fly wheel than would naturally happen.

Reply to
MooseFET

As long as the thread's still here, once someone mentioned the torque converter from the engine to the generator, I've switched over. ;-)

Albeit, I'd still add another flywheel for the generator output side of the torque converter.

Cheers! Rich

Reply to
Rich Grise

How about the obvious and simplest - change or modify the UPS so it is not so sensitive. I know several of my APC UPS's have a desensitizing switch...

They also have a lot of discrete circuitry, at least the older ones, so modifying them might be an option. Another thing, if you ever looked at the typical AC waveform in Urban areas, it does not look like a sine wave, more like a squashed sine wave with dips, missing areas and sometimes huge spikes. Low cost lamp dimmers make some huge spikes! The UPS's I have seem to work fine with that noise, so it may be a zero crossing thing or a frequency thing that the UPS does not like. I know some of the better UPS units manuals talk about using them with a generator, in which the generator may not have a perfect 60Hz.

Also, adding a fluid coupling will waste some of the mechanical energy (the engine will need to run at a slightly higher RPM), resulting in slightly increased fuel consumption.

Reply to
Jeff L

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.