UPDATE Wind Turbine Rotational Speed Question

See this link

LINK

Dale H

The replacement parts for the 3-turbine set suggests the motor is DC.

IF this matches, you should be able to operate your wind-turbines on DC.  In which case you could use an AC-input, DC-output adjustable regulator module.  You hook up your 15V AC to the module input, and the regulated DC module output (e.g., 7V, 8V, whatever you set it to) to the wind-turbines.

Ebay has them $4.30 qty 1 with free shipping from Asia. 

http://www.ebay.com/itm/AC-DC-...;hash=item4ae4409bdd

Or you can pay a bit more and get it faster from Amazon:

http://www.amazon.com/RioRand-...ulator/dp/B00JIMG686

The diode-dropping approach is expedient, but not particularly energy-efficient.  That is, if starting from 15V and diode-dropping down to 7V, the unused 8V goes up as heat.  Less than half of the power from your transformer does actual work (spinning the motor)...the rest is wasted . 

The regulator module is much more efficient is converting the higher-voltage to a lower-voltage.  Albeit you won't see a difference in your electric bill either way but it's kind-of ironic since, after all, these are wind-turbine generators...

Actually if it works on DC a single diode would cut the voltage in half and use little power. Wattage about .7 times the amperage (forward drop). This is because half of the sine wave is completely blocked. A single diode does not use anywhere near the power a resistor would. I live near windmills,They do a nice job of killing off birds,I find perhaps one or 2 a week,usually hawks dead on my property,they must be in the flight path. 

BTW I have the farm windmill. I put it on a repeat cycle timer so it turns on and shuts off as it would with wind gusts.I would guess by observing the electric windmills,they turn maybe half the time. 

Dale H

Interesting solution.

Has anyone had any success in reducing the noise?

Thanks Dale for your information.  I like your repeat cycle timer idea.

I'm going with Stan's approach because the regulator is adjustable.

Thanks Stan for doing this research.

I'm assuming I can run all 3 turbines off the one regulator?

Pete........I have opened one of these up to attempt to quiet them....all efforts failed.

This is the reason for this approach.

They will turn slowly.........low wind days on my layout!!

And Gentlemen................I will monitor my electric bill and report back..

Thank You

Dave

Yes, I find that extremely annoying on mine. 

The diode string is adjustable in .7 volt increments. For DC operation you need only a string in one direction. I ordered some of the power supplies Stan linked for my Miller signs. Been a month and am still waiting. Not sure what makes the noise. Filtered DC from the power supply may quiet it. A capacitor discharge circuit into the motor may produce an interesting random wind effect.

Dale H

Dale

As I mentioned, I never did figure out the noise issue.

They are simple and should be whisper quiet............

I ordered two of the regulators and the ETA is a month for my purchase as well.

Never thought of using them for the Miller signs.

Will I be able to run all 3 turbines off one of these regulators?

I wonder how much of a load they can take?

Thanks

Dave

If the photo matches your guts, you're probably hearing gearbox "rattle" from economical plastic gears.  I'm pretty sure it's a gearbox since the motor shaft and what appears to be the output gear are not co-axial (red lines):

Hard to say for sure from the photo but it looks like the motors are of the less than 1 Watt type.  In which case the regulator module can drive 3 of them without breaking a sweat.

If you're considering cycling the turbines there are low cost eBay cycle timer modules.

Another simple mod that can add interest is a flashing red LED on the nacelle.  Since you'll have regulated DC there are low cost blinking LEDs which only require a resistor (based on the operating DC voltage - apparently 7V in your case).

Dave

The regulators I have are good for 3 amps. Should drive 3 turbines. 3 amps at 8 volts is 24 watts. Turbines would use maybe 5 watts each max,I would think,but I do not have it to test.

I would circuit the turbines with multiple timers and capacitor discharge so they decelerate,to give the impression of random operation and wind. The turbine I see must have governors on them that regulate speed though.

If you have a Radio Shack near you,you may try a single diode in series as mentioned. That would cut voltage in half cheaply. Put one in series to each windmill. 1n4001 or something like that.

Dale H

Can you confirm the noise is coming from the motors? I think I read that at lower speed the noise is less. May be the noise is coming from the turbine blades at high speed? Blade design is very critical in efficiency and noise.

The UH-1 Helicopters used in Nam had a distinct and beautiful main rotor blade noise, most people may have heard it especially in the MASH series.

that noise coming from the blades was due to the blades tips approaching speed of sound!

The problem with diodes is that unless there's good filtering in the windmill, you may get the chatter from half-cycle AC.  The power module Stan suggests will give you pure DC, any chatter from the AC will not be a factor.  Without being there, I can't say that this is a problem, but for sure the DC supply will not cause that issue.

Sam, I seriously doubt the windmill blade tips are getting anywhere close to the speed of sound!

LOL......if the blades were even close, the layout will take off like a bandit out of hell....

Dale / Stan

In the pics you will see the "rectifier diodes" I have.

The #s on them are IN4002 to IN4007.

I've tried to put them in series to reduce the speed of the rotation without success.

Now I did get this to work using a light bulb (18 volt)........just one diode in series did cut the light in half.

Now keep in mind that my skill set in this area is limited!

If I'm using the right parts......can you further advise?

Thank You

Dave

Up to how many diodes did you put in series?  By "without success" does that mean the speed did not decrease?

What I think is happening is there's some kind of electrical regulation/control inside the turbine.  If the photo represents what's in yours, the pink arrow points to be the suspect part.  If this is something you can access easily can you read the lettering on the component?  Or better yet take a good read-able close-up of the entire module showing all the components?  It would be what's on the other side in this photo.

So if there is some kind of internal regulation, that cylindrical component to the left of it is a capacitor.  So even if you take away half of the AC using the diode method, the capacitor stores energy during the active half and releases it during the inactive half.  This derails the diode method!  Of course this is just my opinion though it's again ironic that one of the big issues with wind-turbine generation is it's unpredictable availability requiring energy storage management - ginormous capacitors for example!

Hey Guys,

The REAL ones run extremely slow. I Count the speed on the REAL ones at about 3 to 4 Seconds for one complete revolution. Why would you want to run them at 15 Volts. I run my two at 6 Volts and they are real quiet.

Stan

Pics attached.  I did not get any reduction in speed using the diode (1).

Although, as mentioned, I did with the lightbulb.

Your assessment sounds good.............maybe the pics will bear this out.

Thanks

Dave

Stan

New Pics posted one post before your last.

Dave

That's a 9 volt regulator, so the motor is getting 9 volts.  If you were to replace that with a 5 or 6 volt regulator, you'd get slower speeds.

you could also remove that set of components and run the motor directly from the module Stan posted, that way you'd have fully adjustable speed.

As GRJ says, the man behind the curtain was a 7809 DC voltage regulator IC.  And thanks to your nice photos, we can see the AC is converted to unregulated DC by the RB153 bridge rectifier, smoothed by a 220uF/35V smoothing capacitor, and then into the 7809.

That's good news since this confirms applying DC will work...in spite of the instructions which make no mention of DC.

As configured, the regulator will deliver 9V DC to the motor for accessory voltages of above 12VAC or so...hence the instructions suggesting 12-18VAC.  As you lower the AC voltage to around 10V (or so) the regulator does not have enough input to keep the output steady at 9V DC.  What happens is the internal circuit effectively turns into a resistor dropping a few volts.  It's OK to operate like this (i.e., the regulator IC not actually regulating) and the eBay AC-DC regulator module will work as proposed.

For maximum electrical efficiency, you could do as GRJ suggests and bypass the internal circuit applying the eBay regulator output directly to the motor.  That is, the internal circuit is just dropping voltage (like the diode method) and wasting power.  The decision should be made after careful negotiation with your electric company

Looking inside,the diode in series to the input will not change anything. The capacitor will merely charge the voltage back to peak. I don't have the windmill and did not know it had a regulated circuit inside. For the diodes to do anything leaving the existing circuit you would have to row them up in series in proper polarity with the regulated DC side. Each diode would drop .6 to .7 volts. If you could fit a string of 6 diodes in it would slow considerably.   Lionel actually puts dropping diodes like that in their hobby shop to slow the train in the window.  You could also try replacing the 7809 with a 7805. 

If you put the buck converter in series, and leave the existing electronics,I don't know what would happen.. There would be less voltage than the 7809 needs,it may simply conduct input voltage. Actually it might work,not sure.  Does that thing have a flashing LED also?  The motor should run fine directly off the converter.

Finally you could remove all the guts and just half wave the motor with a single diode. It should run OK on half wave pulsed DC,since it is a DC motor.  If it runs too fast you can string more diodes in series. Without the capacitor and directly to the motor it will slow up. Even at 15 volts AC in the motor would only effectively get 7 so it is protected from over voltage. 

From the pics,the circuit almost looks home made without a PC board. 

The diode solution mentioned,5 or 6 1n4001 type in a single string might fit up in the body. The 1n4001 diodes are fairly small. Here is a link to a bi directional 6 amp dropper for a loco. Yours need not be that heavy. You can leave the circuit in or remove it,either way the diodes should work unless the motor does not like pulsed DC for some reason. I run some loco train motors on it and they work fine half waved. Diodes cost maybe 10 cents each. 

LINK

Dale H

Thanks Guys....

So, the eBay board should work.

I'll report back when I receive it.

Was this whole set up by Lionel a way to ensure that the turbines would never be "too fast"?  Would there have been an easier way to do it or was this the most economical?

While we're here........the diodes I have.......what is the difference between let's say:

IN4001 and IN4007..........I bought a bunch, all varied in one packet.

Just a side note........the weak point on these turbines are the blades.

Too many removals from the "hub" will break off the ends.

Thanks Again for all the help Guys!

Dave

The difference in the diodes are just the reverse voltage rating, for your purposes, you can consider them all equal.

The eBay board will run the motor directly, and it'll give you continuously variable speed.  You could probably run all of them from one module.

I'd think the simplest solution would have been a gearbox that tops out at some maximum allowable (to the mechanism) speed at 18VAC (or whatever). Then the user has full control over speed just like a conventional engine. This would then just have needed the bridge rectifier to perform the AC-to-DC conversion.

Just guessing, but I think the gearbox selection came first (possibly co-opting a gearbox from another higher volume toy), and then the electronics were added second.  Those components in volume cost Lionel maybe 25 cents.  And they could have swapped the 7809 with a 7805 (5 Volt), or 7806 (6 Volt), etc. for the same cost.  It's curious they use "optimal operating speed" to describe what must be when the regulator is in regulation at 9V DC.  That is, these DC motors have a RPM operating speed which maximizes electro-mechanical conversion efficiency (Horsepower vs. Watts, mechanical output vs. electrical input).  But that's textbook stuff.  In the real world usually there's a better story - like they found an unused carton of 7809 regulators...

BTW, with regard to using the eBay regulator, note that the instructions say you can lower the input voltage to slow down the turbine.  Obviously with the 9V regulator in place, the turbine will only slow if the regulator falls out of regulation and delivers less than 9V to the motor.  So ignoring electrical efficiency, you don't have to directly drive the motor if it's a hassle to re-wire/bypass the internal circuit.  In other words, the eBay module indeed lowers the input voltage which is what the instructions say to do to slow down the turbine.

These are not FANS. They are Wind Generators. What is meant by "OPTIMAL"? Probably the person who wrote that, has never seen a "REAL" one. I see them here in Iowa and Nebraska several times a week. They won't make any noise if you run them at "SCALE" Speed like you folks are trying to accomplish. Good luck on your Circuit. I run mine at 5-6 Volts on an old 'Z" Transformer.

John,

I've got a bunch of LM2596 DC-DC voltage regulators. Actually, I got them on your recommendation for some projects last year. I've been using them to reduce voltage to accessories and smoke units to slow them down and they work great. Generally, I use a 6amp diode connected to my AC IN to change it to DC.    

1. Can I use those to these regulators to slow my turbines (2)?

2. Do I have to connect it directly to the motor or can I connect it to the existing circuitry?

3. Can I use the 6 amp diode or should I use a bridge rectifier?

Thanks!

Roger

Sure Roger, they'd work just fine.  You can probably connect up a bunch of turbines to one of them.  Personally, I'd connect directly to the motor, but you can connect it through the existing circuit.  I'd also use a bridge rectifier.

John,

That's good to hear. Thanks!  What is the advantage of connecting to the motor?  I'm thinking I'd like to avoid that if I can as I've got LED wiring I put in there (aircraft lights) and I'd have to deal with that if I opened it up again. 

Roger

You're just not running the regulator in a somewhat undefined operational state, but I've never known one to be damaged by undervoltage.

Try it, if it cooks the regulator for some reason, there's the fallback position of connecting directly to the motor.

The 12-18 volt input recommendation would be to run the regulator properly, with something on the side closer to 12 volts being the most efficient.  I'm curious what the voltage rating of the motor it's self is on these, but for the sake of argument I'll assume it is a 9 volt motor, and that is why they regulate it to that voltage.  As far as the speed, i agree with others that the motor and gearbox were likely scavenged from some other application with no thought whatsoever to attaining a prototypical speed.  

I like the idea of adding diodes in series  between the motor and regulator, and it is probably the strongest solution on the easy and cheap.  The other thought that comes to mind is putting a potentiometer in line (between regulator and motor) so you can adjust the speed to your liking.  It's not the strongest option, but for a low current motor running with no practical load I think it would work out just fine.  

John,

Just finished adding the LM2596 to the connected circuits of my two turbines. Works flawlessly. Now I have to fiddle with the adjustment screw to fine tune them. Presently, they are running at 8.25 volts and the rotational speed is about 6 seconds/ rotation. I may speed that up a bit. 

Dave,

Thanks for starting this thread. I've wanted to do this since I got them and this gave me the excuse.

-Roger

UPDATE

Well the AC to DC adjustable circuits arrived from China today.

I bought 2 and they both work well.  The 2 came as one board.  I had to "snap" them apart down the centre.  The adjustment screw has a long range so keep turning until the desired result is achieved.

Now on to wiring all of this together.

Not only will the blades turn nice and slow without noise......but the birds can continue nesting peacefully...................

Thanks for the follow-up.  So you'll soon be putting energy onto the grid!

The screw-adjustments on these modules are typically 20, 25 or 30 turns - typically translating to about 1 Volt per turn.  There's a clever slip-clutch mechanism so you don't run into a hard mechanical stop at the end-of-rotation but rather it just slips on the final CW or CCW turn without damage.

Several guys have posted that the adjustment screw on their module was broken...but it was simply because, like you say, you have to "keep turning".  It's not obvious such a tiny device has so many turns/resolution.