37,000w+ for 1 minute, Motor/motors?

[magudaman]

I am looking at a project that would have small lightweight motor or motors that would output around 50 horsepower for around 50 to 60 seconds. I have recently been looking at some of the interesting looking RC helicopter motors and transmissions that do 5,500w continuous and 12KW peak in crazy in 1KG (including gearbox) package that have a output speed of 2900RPM. With say 4 of these motors working together its seems my 50hp could be achievable. There was aways the ever elusive motor that recumbrence was putting together with Astro that never seemed to get past the prototypes.

The other thought is there maybe a lot of motors that could handle insane 1 minute runs but then would need to be completely shut off to cool down. I assume your really start to run into motor saturation problem and really are just loosing efficiency.

[amberwolf]

My guess is you wouldn't want to shut it down, but rather to keep spinning it under no load, so you don't end up heatsoaking the stator and magnets with zero airflow to convect the heat to the covers or outside of the motor (assuming you have no active cooling system).

[neptronix]

My guess is you wouldn't want to shut it down, but rather to keep spinning it under no load, so you don't end up heatsoaking the stator and magnets with zero airflow to convect the heat to the covers or outside of the motor (assuming you have no active cooling system).

+1

When i was doing hill climbs at 3-4kW on my magic pie, spinning it in the air cooled it down pretty rapidly ( versus letting it just sit there and let the copper soak everything nearby with heat ).

Magudaman, if you want a motor like that, it's gonna be flippin' expensive and require all sorts of reductions because the RPM will be stupidly high.. what about a giant big block motor like what Luke is running?

I like the motenergy 4201... or even better.. the dual stator version.. both are 50rpm per volt.. perfect for our application.

http://www.cloudelectric.com/product-p/mo-me-0913.htm

[magudaman]

Yah good call, most of the motors I have seen usually have a cooling fan integrated but do require the motor to be spinning. The motenergy motor seem to be heavy for their power output numbers but I'm sure they will last for ever. They seem to be more suited to electric motorcycles than the bikes, though that line is always blurring.

[neptronix]

Oh yes, always blurry

Just think of what luke has pulled off with a "10kw" motor. I don't know his power record right now, but i remember hearing something about 30-40kW for short periods of time..

[frogblender]

50HP and "small lightweight motor".... hmmm.

Can you inject liquid nitrogen? You wouldn't need a whole lot for only 60 seconds. And a spray into the motor wouldn't be too hard to plumb. And if you started the flow 5 or 10 seconds before running the motor, your windings'd be nice and cool and very conductive.

[ProDigit]

You will want to keep the motors cool, by installing them in an aluminum frame.
It's quite possible to overload a motor for short term (when they're cold).
And with a good cooling capacity (like the mounts made out of aluminum, part of the frame where they're built on, out of aluminum, perhaps some aluminum heat sinks).

Motors that handle 3kW, can easily handle 5kW for a few seconds. For a whole minute is another thing.
Also know, that when overloading something, the device heats up quite fast. Doing so, they expand rapidly, and almost any material expanding rapidly, (or fluxuating between expanding and shrinking) is prone to metal fatigue.

[bearing]

An Agni 95R or 111R would probably be able to output 37kW @ 6000 rpm for 1 minute.

[Biff]

These guys advertise something in that power range, they say 40kW, 8kg

http://www.freeair.cz/freeairen/index.p ... &Itemid=53

no idea if they actually have a controller that will deal with that.

Here is another one that would probably do the trick

http://www.rs-e-motoren.de/joomla/index ... &Itemid=79


As you can see they are pretty pricey, what you are asking for is not an easy thing to accomplish.

-ryan

[magudaman]

Resurrected!!! I eneded up picking up a 80-100 to play with and fitted it with hall sensors and two temp probes for some serious testing! I probably start up a new thread and post it here if anyone is interested.

[Miles]

See: viewtopic.php?f=30&t=44287

[magudaman]

Thanks Miles, I'm going to be interested in what it can do for short term spurts while trying to avoid cooking a coil. I think the next real project is to get a sort of torque based dyno put together to actually extract some data.

[John in CR]

What's the load or application? If 1/3 to 1/2 of that minute is spent getting up to full power rpm it's a totally different problem to solve than quickly jumping to high power and holding it for 1 minute with the latter being not terribly difficult. 37kw of heat reducing to about 5kw of waste heat over a 30 second duration is no small matter, and while I have a couple of motors that would probably handle 50kw input for a minute, I wouldn't even think of trying it with such a heavy load that it takes half the time just to get up to speed.