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View Full Version : Direct-drive washing machine motor....any way to make something useful out of it?



winchman
12-25-2012, 12:36 AM
I know there have been several threads about converting treadmill motors to power machine tools, but how about the direct-drive washing machine motors. I've read some about converting them to generators, but was wondering if anyone here had used them for powering tools.

https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcROCaPcjoBzxRKeJnpeH6a9M_DgfYgM9 PKBIN5jCNvUp7ZK8sYF

If nothing else, the rotor has a bunch of magnets.

The Artful Bodger
12-25-2012, 12:48 AM
There has been a lot of work done with these in years gone by, this site has a lot of information...
http://www.thebackshed.com/forum/home.asp just search for F&P, Fisher and Paykel were one of the first appliance makers to use this type of motor (about 20 years ago) and they have been stacked up in recycling piles in New Zealand and Australia for some time.

Yes, they make effective generators and have been especially favoured by the wind turbine guys as they put out useful power at low RPM. They have also been used in small electric vehicles.

They are of course stepper motors and can be driven like any other stepper but they are mostly, if not all, 3 phase in operation as there are three series of stator coils. (Nothing directly to do with 3 phase mains).

They have plenty of torque and can be directly mounted on mill table feed screws etc. I suppose they could be used in a direct drive lathe project but I have not heard of anyone doing that.

darryl
12-25-2012, 03:46 AM
I've considered putting one on my lathe- directly mounting the magnet wheel on the spindle. The only thing stopping me is the fact that it will add a lot of momentum to the spindle. If you have a crash, that will probably make things worse. It could of course be mounted as part of a clutch pack- something that would allow it to slip when a certain level of torque is reached. There may be balance issues as well.

I have a few of these motors. I see the specs on one at least say 310 volts, 5,5 amps, 2000 rpm. It's wired star, but all the wire ends are available so it could also be re-wired delta. I have yet to figure out the module, but it seems that the module is a failure-prone item. I don't know how true this is, but the other problem would be getting the proper voltages to the right wires to be able to use the module. Then of course you would have to come up with the power circuitry to drive the coils.

The Artful Bodger
12-25-2012, 04:10 AM
The original F & P electronics are reliable enough in their intended application but prone to sudden death when being messed with. It is also difficult, if not impossible, to get reliable circuit information.

Considering the F & P machines were on the market 20 years ago there are probably better, easier, cheaper ways of driving them.

The balance of the rotors is pretty good, in my experience.

Fortunately the stator coils are easily reconfigured to various combinations of serial/parallel as may be required for low voltage operation.

The star point of the motors I have is just a metal clip that pulls off.

Deus Machina
12-25-2012, 05:04 AM
I'm a member of my school's Electrathon electric car race team.
One of the big contenders (he's a one-person team!) is using a 3-phase motor that, I believe, may be out of (or offered for) industrial washers.
I asked a bit, but information on a competitor's vehicle is understandably not always freely shared.

topct
12-25-2012, 08:35 AM
What brand or brands of machines have these motors here in the states?

I could Google it I guess, I'd be curious about any hacks for the controller?

Lew Hartswick
12-25-2012, 08:43 AM
The drive circuitry sounds like an interesting "reverse engineering" problem.
Wish I had one to look at. I've done quite a few switch mode power supplies
in my time. :-) If they have been around for as long as is indicated above
the components should be identifiable. ie. not some OEM specific part like
a few computer manufacturers in the past. :-)
...lew...

alanganes
12-25-2012, 08:55 AM
I've repaired a couple of the drives for direct drive washing machine motors a few years back. Not sure if the motors looked exactly like that or not, these were USA consumer brands but I forget which. The ones I saw looked to be essentially VFD's, they had no hall sensors, just a 3 phase output. These used discrete IGBT's for the outputs (which were blown up), I'd guess the newer ones are more integrated now. Might be a fun thing to mess around with. On the other hand, "real" VFD's are pretty easily available at some pretty reasonable prices these days. So it may not be worth the bother from a cost standpoint. If one wants to fool with one just for the fun of it and to see if you can make it go, I certainly understand (and applaud!) that.

The Artful Bodger
12-25-2012, 01:48 PM
The original F&P motors have a hall effect sensor.

The motors might turn quite slow on a regular VFD as they have many poles.

lakeside53
12-25-2012, 02:09 PM
The original F&P motors have a hall effect sensor.

The motors might turn quite slow on a regular VFD as they have many poles.

That's ok, the Hitachi WJ200 can go up to the usual vfd max of 8 poles, but also 1000 hz :)

The Artful Bodger
12-25-2012, 02:29 PM
I think the original motors had 14 poles but please dont ask me to stand next to one if you put 1kHz on it!;)

It sure would be interesting to try one on a VFD but I fear the voltages would be far to high for the motor especially at low RPM. It is very unlikely that I would get to try one as VFDs seem very expensive in this country.

rklopp
12-25-2012, 09:13 PM
LG and Asko are two current brands using direct drives. I think at least some of the Askos are rebadged Daewoo machines. Daewoo may also supply other brands, e.g, Kenmore - but I'm not sure.

The Artful Bodger
12-25-2012, 11:06 PM
Both Whirlpool and Maytag use the F&P motors, maybe others do too.

winchman
12-26-2012, 01:48 AM
So, what's the worst thing that could happen if you hooked up a 1HP VFD to the three big wires on the F&P motor?

On the other hand, seems like it would make a really good brake by putting DC on it.

The Artful Bodger
12-26-2012, 02:02 AM
It will probably whirr and buzz and likely heat up, it might even turn but dont forget they are permanent magnet motors and putting AC on the stator coils will have uncertain results, IMHO.

They make a very good brake just by shorting the leads.

lakeside53
12-26-2012, 02:10 AM
The Wj200 series has a setup for pemanent magnet motors, and you can put it in "learn" mode where it figures out the motor characteristics. Pity I don't have access to a scrap pile of F&P stuff; here they are somewhat high end and I'm even sure they well the washing machines and dryers here. Might pick up a couple of motors next I'm in CHCH, or maybe have a McChord buddy bring some back on a C17 ;)

The Artful Bodger
12-26-2012, 02:25 AM
You would not be the first as Fisher and Paykel stuff has been getting flown out of Chch since the times when a Globemaster was a C124.

darryl
12-26-2012, 05:39 AM
I think if you fed 3 ph 60 hz to one of these motors it would vibrate and buzz, then burn out. The only way it would work is if you sped the motor up to some exact rpm, then synchronized it to the input frequency before applying power. Then it would stay locked to the power line frequency. The moment a load causes it to lose lock, it would vibrate, buzz, and burn out. I'm pretty sure it's going to need sensor control.

A smart enough VFD could run it without sensors, but I don't think the operation would be trouble-free. It seems to me you would have to stay within certain parameters of operation in regards to loading and rpms. My own plan is to use optical sensors, either the type that works from one side of a sensor disk with reflective areas on it, or the ones where the disc passes between the sender and receiver. The reflective type is probably easier since the sensing is just a pattern of reflective areas interspersed with flat black areas, so it can basically just be painted on to part of the rotating surface.

Lew Hartswick
12-26-2012, 09:13 AM
since the times when a Globemaster was a C124.
Aren't they still?? I had a tour of one back when they came out. At Greneer AFB
(Sp?) It's been over 60 years. :-)
...lew...

macona
12-26-2012, 10:37 AM
You cannot run brushless motors with a VFD. Putting one of these motors on a VFD will probably just trip the overcurrent limit in the drive. Typically brushless motors have very low inductance so they will sink whatever current you put in there. You will either trip the vfd, fry the coils, or demagnetize the magnets. Maybe all of them. Worst case you will toast the VFD.

What might work is the big, big brushless model airplane motor drives. These would probably run one. Some of the big ones will handle quite a bit of power.

There are also sensorless brushless drive controller chips available from companies like Analog Devices. You could build something around one of those. Or use a more generic brushless driver and use the hall feedback. You will probably get better performance at low speeds.

lakeside53
12-26-2012, 11:52 AM
You can with the new Hitachi vfds (WJ series). You can't "position and hold" but they seem to have the rest covered (apart from a simple explanation of that portion of the online manual "addendum"!...). One day I need to fiddle with the PM modes.

skunkworks
06-04-2013, 08:11 AM
andy is playing with one for a lathe spindle...

https://www.youtube.com/watch?v=_P027KQ8ZHo

(linuxcnc and mesa brushless drive)

sam