Originally posted by revizal
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Hi Rev, yes you can create resonance from the induction 1 PH motor it will not be as much VARS to convert into usable watts as the 3PH but it is still possible, also the 1PH does not have as much of an impedance so i imagine you will need bigger caps for it
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New RV setup on 2 HP 3 PH motor
Hi All,
I try RV mode on a 2 HP 3 PH AC Induction Motor today. I got a good result (less than 100 mA drawing current) on idle. But (may be someone can explain/tell me) why there is a humming sound around the cap when the start cap + running caps being connected to motor lead ? And this sound gone since I disconnect/switch off the start cap without any change in RPM.
Here is my video link:
YouTube - RV-2 HP 3 PH AC induction Motor
Rev.Last edited by revizal; 01-09-2009, 12:45 AM.
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Hi Mart, Rev and all.
Great Vid Rev
, imagine if your induction motor had a permanent magnet rotor... There would be no slip loss and it would probably be around 100% efficient.
They have made an induction motor here with a PM rotor
(YouTube - Ingersoll Rand Hybrid Permanent Motor (HPM))
This was the RV concept years ago, but we never could get one machined plus you have to be careful of the magnetic DRAG if you make one (read compilations). With an AC motor control or hacked frequency driven inverter and a PM rotor, you would have a superior induction motor.
Now i think the noise is because of the resonance and the semi resonant state, you will notice this when you hook your alternator up if you do, that the "hum" is where it gets in/out of the resonance and sweet spot.
Don't forget you will probably only get 1/4 (as your driving it at one quarter of the voltage rating) at the shaft, with a 2HP that will not be much but still will have a power factor close to 1. (maybe up to 94% efficient).
With that at idle and a half a HP load you could run that from a solar panel
If you re grease your bearings with low friction lube it will be more efficient also don't forget to take off rear cooling fan if you have not already
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Wish there was easy inverter hacks to do, i woild love to see tha frquency driven,
@mart, i just need to check with Andrew (Panacea techie) what rating to get, sorry i missed your Q yesterday man.
Ash
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Hi Rev, i just found soe good advice on the EVGRAY yahoo group for first timers from Dan.
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This is where I bought my caps. I had those shipped to Europe.
<http://www.surpluscenter.com/sort.as...tname=electric
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Originally posted by ashtweth View PostHi Rev, i just found soe good advice on the EVGRAY yahoo group for first timers from Dan.
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Once you have your first motor running (as prime mover) in RV mode, start
putting your 2nd motor (called Alt or alternator). Connect the shafts
face-to-face. Wire that motor for 400V, so in delta (reason is no to
generate too high voltages - stay safe). Gradually add run caps on the Alt
across 2 of the 3 phases, until it starts to 'generate'. You will notice
that - different sound - current flowing (put amp or clamp meter & measure
voltage). Add caps until you get high circulating current running. Whilst
you do that you will need to adjust the run caps on the primary mover. Do
this carefully and slowly. Learn as you go and understand the thing - don't
go too fast as these are dangerous toys. (Hector would say : zziippppp
ripppppp);
-Dan
Hi Ash,
I almost complete my project on RV motor. Just ordered a motors mounting which could able to adjust 2nd motor position on it. I've tried adapt to run the other motor (my last small water pump motor) with a belt. It seems enough to hold 2 motors.
How about if I connect next motor with a belting. Could I still get a resonant alternator on it ?
Or it must run face-to-face setup only ?
Rev.Last edited by revizal; 01-10-2009, 08:58 AM.
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Hi Rev, sorry guys just got in. Mart i have the value of the Pot for you, here will post tonight.
Rev, yes you can add a belt, it will have a slight LOSS as friction etc, but some already coupled an RV with a belt, you can even step it up (gear pulley etc) and get it to go faster, dont forget to TUNE Run cap in prime mover.
Ash
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Originally posted by ashtweth View PostHi Rev, sorry guys just got in. Mart i have the value of the Pot for you, here will post tonight.
Rev, yes you can add a belt, it will have a slight LOSS as friction etc, but some already coupled an RV with a belt, you can even step it up (gear pulley etc) and get it to go faster, dont forget to TUNE Run cap in prime mover.
Ash
OK Ash. I will use a belt to drive my alternator first. And will go next with head to head coupling to see different effect of setup. I'm waiting for a 3 HP 3 PH 2850 RPM motor to set as the motor on this experiment. My last motor 2 HP 3 PH (lower RPM) will choose as the alternator. May be tomorrow will be come to me.
Thank you for your very usefull information here.
Rev.
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RE: Size of pot
Originally posted by ashtweth View PostFor Mart.
24mm size pot as its for the signal, this should be fine
Ok, but I need the wattage of the pot, ohms are given.
Also can I move the pot while the motor is running? Do I use a scope to tune it ?
Thanks!See my experiments here...
http://www.youtube.com/marthale7
You do not have to prove something for it to be true. However, you do have to prove something for others to believe it true.
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Mart the pot is specified for 100K in the document, try a half a watt one.
As for tuning, you can tune the frequency up SLOWLY, and let the motor catch up to speed, do not turn it down when its operating, be careful switching in caps, you could blow the inverter from BEMF.
You tune it by the following procedure specified, in the compilations.
The higher the frequency the lower the capacitance needed (RUN CAP).
Ash
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RE: so far so good.
Ash,Originally posted by ashtweth View PostMart the pot is specified for 100K in the document, try a half a watt one.
As for tuning, you can tune the frequency up SLOWLY, and let the motor catch up to speed, do not turn it down when its operating, be careful switching in caps, you could blow the inverter from BEMF.
You tune it by the following procedure specified, in the compilations.
The higher the frequency the lower the capacitance needed (RUN CAP).
Ash
Ok, I have installed the 100K pot, I have hooked up the killo watt meter to this and sometimes it comes on other times it does not, when it does come on and the killo watt metter is working, i can see the frequency move around.
I have plugged in a light, and the inverter power it just fine...
Any suggestions for my first power up of the inverter? My plan is put the run cap on, get the motor up to speed then turn the run cap off then note the power of the motor after that.
Thanks for your help.
MartSee my experiments here...
http://www.youtube.com/marthale7
You do not have to prove something for it to be true. However, you do have to prove something for others to believe it true.
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Frequency drive inverter now working!
I played around with the pot on the hacked inverter, I found it draws from 2.3 amps at 12.3V on my battery up to about 11 Amps.
As I increased the amps from 2.3amps to 11 amps the motor spun at faster revs. So, I could tune this per a set load which is kinda nice.
This is progress so far. I have had many headaces to get so far as I had to fix things that I missed on the inverter, and I also took apart the motor again and removed the seals on the bearing. I have cleaned them far better than ever before with the carb cleaner and put the duralube inside.
On a side note, my killa watt meter stopped working after I was testing the output of the inverter... hope I just blew a fuse.See my experiments here...
http://www.youtube.com/marthale7
You do not have to prove something for it to be true. However, you do have to prove something for others to believe it true.
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Hi Ash and All,
After a couple of days to do some business I made a test on RV mode to have resonance effect on 2nd motor as alternator. I have 3 PH 3 HP motor that I used as a prime mover driving the 2 HP 3 PH motor (act as alternator) via a belt.
I found the main thing on the system is speed/RPM. If I could get speed with lowest power input, I will get higher voltage on the alternator. And I'm sure we could control the output frequency thru this speed too. We tune the capacitor to have lowest power input on PM with the fastest we can get to get power output.
Yes Ash, I got it. My first target is to sure the resonance work on the alternator and I got that. Next target is to tune the system with my capacitor available. We'll se..
Here is the video link:
YouTube - RV-Coupled 3 PH Motor as Alternator
Thank you very much for your previously info on RV setup.
Rev.
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Hi Rev, keep going its easy after this first stage and you automatically get an intuitive sense on tuning. The extraction circuits are well advanced and takes a lot of patience, this is see you have
Please post your progress ALSO over here too Bro
(all the RV engineers strangely only converse at this group)
EVGRAY : zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
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