have 400hp 4000VAC 3-phase 53 amp Electric motor. Need help sizing components

[sirus20x6]

I recently acquired a General Electric motor. 400hp, 4000VAC, 53.1 amp, 3-phase, power factor 85.0, rpm 1190, weight 5250 pounds, size 6'x3'x3'.

I need help sizing the rest of the system. Where do I even start with something this large?

[hiker]

That's huge....hydro power..? Really dout if anyone here has tackled a monster like that...!  you could go with caps for power or make a mag rotor for it...be fun to set up..

[sirus20x6]

I think i'm going to greatly limit this thing to start. partially because of cost and partially because from looking up Illinois power laws it looks like if my system is under 40kw the electric company pays for the grid tie. after I have it running for a few months I can begin planning what a full scale optimized system might look like. I guess I should have mentioned that to begin with.

[kitestrings]

That's going to be a challenge to get on a tower  .

[SparWeb]

What are you going to drive it with?  What fuel source/energy source do you have access to?  Will it be cheaper than grid power when it's tied in?

[sirus20x6]

I'm going to power it with wind of course

I found a deal on 3x 6' blades that might be ok to start with, but I'm thinking I want at least 10' blades, and to run this thing at full power I'd need way way bigger ones than that but I don't want to try to do too much all at once.

I have some steel farm silos that haven't been used in decades for anything farm related. I think could be reinforced with a few steel I-beams and some concrete. Then I could hoist the motor up there.

[kitestrings]

sirus,

I assumed that you were either joking with us, or that you had some really ambitious hydro application and just inadvertently to posted on the wind section.  Anyway, here's my opinion:

If you are serious, I would encourage you to stop now, and do some research; here and thru other means (books, other sites).  This is way, way too big for anything practical for wind - short of near utility scale.

Consider that with a 6' diameter prop you'd be doing very well to get 400 watts at 20 mph, and the theoretical limit at that windspeed is only about 650 watts, or .65 kW.  At 400 hp, if you could drive this thing, you are up in the 300 kW range.  You're looking at three orders of magnitude (1,000x) larger than what you can practically do.  Beyond that, this thing is way too heavy to consider putting in the air, even on a silo, without significant engineering.  Please be safe.

~ks

[sirus20x6]

sorry not joking. i just picked her up  400-650 watts would be fine to start tinkering with. yes it is 212,000 watt motor and with some large steel i beams getting it a few dozen feet up in the air wont be impossible. one of my degrees is an engineering degree so that's a start.

[dbcollen]

To run it as an induction generator you will need to spin it at 1210rpm, which is too high rpm for a large wind turbine. 650 watts will probably not overcome core inertia and bearing friction.

[dnix71]

Even if you can raise it in the air, for the sake of safety and service it should be on an low elevated platform. (Elevated enough to keep it dry and from accidental contact with animals and people).

You will need to spin it synchronous to get any power out since it doesn't have magnets. That won't happen with 6 foot blades. Adding a gear box or pulleys to make speed control practical will still require some power just to operate the gears/pulleys. If you have a 5HP electric motor in the shop, see how much power it takes just to make it freewheel. Couple pulley to pulley 3 to 1 and see if you can make it spin 1200 rpm, assuming you have a 3600 rpm common motor.

A motor that size could drive an oil rig platform using tidal/wave forces. The Dutch have scalable ocean electric generators that have modules of the size of that motor. https://seaenergytag.wordpress.com/tag/netherlands/

This Chinese wind turbine is rated up to 200 kw and uses three 80 foot blades.

https://en.wind-turbine-models.com/turbines/1681-hummer-h25.0-200kw

[joestue]

There is no need to get that thing running at 1200 rpm to get power from it.
 
A 480v VFD would be a good start but perhaps a 240v vfd can provide enough volts if the rpm and the torque is low enough. you will need to figure out how to program something like an arduino to command the vfd to drive the motor at less than the wind speed so the motor back drives the vfd. as long as the torque is substantially lower than nameplate values (1765 foot pounds) divided by the ratio of rpm (so at 119 rpm, at less than 176 foot pounds the motor will still be approximately as efficient as its nameplate value, in this case about 95%)  however at full load torque of 1765 foot pounds, at 120 rpm you would be looking at an efficiency on the order of 50 to 75%.

You may be able to reconnect that motor in delta for 2300 volts rather easily but doing so would kill the resale value if you do it yourself due to the high voltage issues.

my 5 hp motor runs just fine on 20vac single phase, drawing about 2 amps at nearly unity power factor, at 17xx rpm with its cooling fan connected, without the fan the power consumption is 2-4 watts less. at 240 volts single phase the power draw at no load is more like 250 watts.

you will probably see similar ratios with your motor. if you can get it up to 1200 rpm with a pony motor, you should be able to plug it into 240v single phase and it might stay running, drawing on the order of 10-20 amps of current.

[SparWeb]

sirus,
You are trying to drive a dump truck with a lawnmower engine.  I am very happy to be the naysayer in this scenario.  The opportunity for disaster if you raise this off the ground is great.  That's compounded by the high voltage that's also involved.  Please find someone to sell this motor to, before you use or modify it.


I am also disappointed to read another member encouraging this project.  Your posts are normally much more technically rigorous. 
While extreme projects may be fun to read about, this is an adventure into the realm of very high voltage where even professionals tread carefully.

[joestue]

No need for high voltage. 480v ac might be enough for direct drive 20 foot diameter blades, if not then reconnect the motor for delta.

A second vfd could be used to drive a transformer to turn the 700 volts youll get from the vfd to whatever you want, ac 60hz or rectify to dc to charge batteries, or both.

Youll need a 700v battery bank, maybe  500 aa nimh batteries could work.

[kitestrings]

"No need for high voltage", yet you're encouraging someone's first project to incorporate 480V...480V VFD...700V batteries.  To be clear, 480VAC should technically not be approached by anyone without proper understanding, training and PPE - this means (20 cal) arch-flash clothing & balaclava, safety glasses at a minimum, flash-shield, ear protection and EH footwear.  And no utility is going to want this thing paralleled with their system if that is being suggested.

sirus, I wouldn't intentionally discourage anyone from thinking outside of the box, or even just pushing the limits of excepted norms, but frankly I think you are getting very poor advice here.  In the best outcome you are going to put a sh**load of work in to this project, and in the predictable end be disappointed that it was not successful.  In the worst case, you could be seriously, unnecessarily, injured or worse.

I'd sell this thing for something close to it's intended design, take the money and start fresh at a more appropriate scale.  Above all, please be safe.  ~ks

[johnnym]

Wow, that is huge. Yeah, the utility companies won't accept this. Cool idea but I think you bit off more than you can chew if you plan on using that monster with wind. Good luck and be safe.

[joestue]

480 volts isn't even medium voltage.

i figured Sparweb was confused by my suggestion to rewire the motor for 2300 volts.

anyhow if you can get 12 foot diameter blades to turn the motor then 240vac would probably be enough volts. the problem being larger blades turn slower, and torque follows the cube of the diameter.


anyhow, on a serious note: it might be better to find a scrap motor that size. get a 2-4 inch slice of the lamination stack and build a concentrated pole motor. a 6 pole motor that size might be 54 slots, so 46 poles is a good number.

[kitestrings]

I missed the most important one, in PPE, rubber gloves.

480 volts isn't even medium voltage.

It is true that 227/480V is pretty common in commercial and industrial applications.  And, if we're talking about a wye configuration , then yes, we are technically below 300V which, I suspect is what you mean.  Even 277V (L-neut/grnd) IIRC puts the current level, in the event of a shock, above the 15 mA "lock-on" threshold.  Every year there are electricians, and workers injured or killed often when 277V lighting circuits are in use and the risk is unknown, or the right precautions are not taken.  But google "480V arch flash" and see if you get any hits.  A phase to phase fault, particularly in a box, is a violent event that in about a third of second forever changes the life of the unprotected worker in front of it; if he lives.

I don't know the OP's knowlege or skillset, but to be cavalere about these risks is quite reckless IMO.

[Mary B]

And if you rectify this to DC it becomes even more dangerous! 1kv at 1amp can blow your finger off! I have seen ham radio operators with missing fingers because they failed to make sure the capacitor bank in an amplifier was discharged and they ended up doing it through a finger! And Some who ended up dead...

[sirus20x6]

There is no need to get that thing running at 1200 rpm to get power from it.
 
A 480v VFD would be a good start but perhaps a 240v vfd can provide enough volts if the rpm and the torque is low enough. you will need to figure out how to program something like an arduino to command the vfd to drive the motor at less than the wind speed so the motor back drives the vfd. as long as the torque is substantially lower than nameplate values (1765 foot pounds) divided by the ratio of rpm (so at 119 rpm, at less than 176 foot pounds the motor will still be approximately as efficient as its nameplate value, in this case about 95%)  however at full load torque of 1765 foot pounds, at 120 rpm you would be looking at an efficiency on the order of 50 to 75%.

I do embedded systems hardware and software engineering so I think i can muster something along the lines of an arduino I'm thinking more like a cortex arm m4. Thanks for the tips!

[sirus20x6]

I'd sell this thing for something close to it's intended design, take the money and start fresh at a more appropriate scale.  Above all, please be safe.  ~ks

Well I paid $500 for it at auction from the Wisconsin state government and they said it was in full working order when removed from service. it was just not a currently manufactured model so they wanted to make sure they had something they would be able to get parts for.

There is an extremely similar model that just sold for $10k (plus $500 shipping) on ebay
( it's not letting me post links but if you search ebay completed sold listings for "400HP 3 phase GE electric motor 5011LL frame,1785 RPM, TEFC,460 voltage" you should find it)

so selling it and using the money to buy something else isn't out of the question.

[dnix71]

kitestrings 480v stepped down through a transformer was used for bus stops in south Florida until people got killed in the rain because the enclosures weren't grounded properly. The electrician who installed many of the lighting systems under contract couldn't get a decent ground because there is solid limestone under the few inches of dirt we have here. Low bid contract = he didn't say anything. FPL grounds their poles by using a large auger to drill deep enough to hit water before setting the pole and ground wire.
Now bus stop lighting is solar/led, and street lighting is about to be converted county wide to led too.

https://www.youtube.com/watch?v=-iClXrd50Z8  Here is a 480v arc flash.

https://www.youtube.com/watch?v=hV0IlPDkfQM  "Only" 240v arc flash.

[DanG]

Excepting prior tunnel vision - doing a zubbly conversion with new lightweight armature using massive Neo's could make that frame/winding flux bottle overflow nicely... 

I'm guessing a complete compliment of magnets would not be necessary to begin with, yes provisions made for swapping them in the future, maybe modular/swappable fiberglass/epoxy sleeves to provide 30% or 20% magnet insertion for testing...  On cost basis turning down existing armature might be best saved for the final version and a new shaft w/ aluminum core that accepts sleeves for testing could be worthwhile..

[kitestrings]

Excepting quixotic strategies, take the money and get something that actually fits your needs.

[tanner0441]

Hi

One question no one has asked is. Why was it taken out of service? Some, no many years ago I worked on some Vickers 11000 V  variable pitch water pumps. Apart from switch gear problems we had winding flash over and 4000 V is high enough to flash between windings.

Motors like that are only normally installed to work hard, too expensive as an in stock off the shelf item.

Blade size I would think your looking at 30 ft then they wont be happy at 1200RPM so a gear box. More friction to overcome.

I would find the history and condition of the motor, advertise it in a trade magazine and use the money to buy or build something that is doable, and wont encore the wrath of your neighbours or local authority.

Brian