Electric motor coupled to a PMA

[gyulasun]

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Now one would think that if the motor and generator both have losses,then the thing should wind down to a stop quicker?
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Hi tinman,

My take on why they do not wind down much quicker is that they are nearly "matched".

I mean the motor have T torque at a load and at an I input power and the generator is able to supply around I output power when rotated by the T torque on its shaft.  These are basic requirements for a longer wind-down to occur but eventually the setup winds down due to the copper and friction losses.

There might be one hope I can see here for such setup to maintain operation: once we have such well matched motor and generator then we could try to achieve electrical resonance by tuning capacitors in parallel with them so that the reactive currents in the coils could be enhanced Q times as much, like Hector Perres's rotoverter principle but in this case the useful torque output (if any) would be tied to a given RPM and whenever the load would increase, the chances of falling the system apart and eventually stop would be high.  I do not say this will surely maintain operation because I have not tried such setup but I do not reject it off hand if resonant operation would be involved. Here I mean that say the motor-generator combination has an L resultant inductance when they are hooked up (and this L would fluctuate in a range in the function of RPM, unfortunately) and for this L value you find a C (run cap type) capacitor which would give resonance with L at the frequency of the RPM.

rgds, Gyula

PS In my answer with respect to the fan motor - PMA case of the first post above I considered the huge power differences involved between the two.  There are several patents from the past 50 or more years which show exactly this: connecting a motor shaft directly or via gear to a generator and hooking them parallel electrically too and claiming a continuous operation. However, I have been aware of failures only.  OF course we should try and do much more testings. 

EDIT:  In the video Robert33, he uses a series resistor (he calls it a low resistance, attenuator) this further reduces the wind down time...

[returnedintime]

Hi returnedintime,

it would be nice if it could work. However, you have not mentioned how many Volts your PMA puts out when it reaches 12.7 Amps at 950 rpm. It could be in the 12 volts range to keep a battery charged?... that would be about 150 Watts.

Now your fan motor probably works on 120 Volts AC and at 2.6 Amps it would come to a little over 300 Watts.

If you're low on cash I would not invest money in this, as many have tried this before. I wish it would be so simple

Nothing wrong in thinking of alternative energy solutions but using off the shelf items chances it would work are next to none.

I wish you all the best in your search for a solution

Luc

I appreciate your feedback,....which gives me reason for pause,....my thinking is that I am on the right track,..but using the wrong PMA,...with that thought in mind,..what are your thoughts of using a pma that produces 1000 Watts at 999 rpm, using the same electric fan motor as mentioned in earlier posts?
The PMA uses a slant core system that makes the PMA vertually coggless.

[returnedintime]

Hi,

On 'heavier load' I mean as follows:  you use say a 12 Ohm power resistor as a load across the output of your alternator, the current draw will be 1 Amper if the alternator output voltage is around 12V. Now suppose you replace the 12 Ohm resistor with a 2 Ohm power resistor,  this is what I call a heavier load because the current draw goes up to at least 6 Amper provided the alternator keeps its output voltage at 12V as earlier.   

Some more notes:  it would be good for you to feel the torque by your gloved hand on the shaft this PMA must receive from the wind or from any other prime mover when it rotates at 950 RPM and you take the 12.7 Amper out of it.  Will the fan motor be able maintain that much torque on its shaft when the PMA is tied to it?  The only correct answer you can get is to test this and see for yourself. I understand you do not belive us, this is natural.

rgds,  Gyula

Thanks for your input,.....I'm already convinced that I was targeting the wrong PMA.....I'm thinking of a much more powerful PMA that uses slant core technology(Makes it coggless) and by using a 12 Volt, 5 amp. (60 Watts) halogen light bulb. Just hand cranking the PMA brings this light bulb to maximum power.

[gyulasun]

returnedintime:

Cogging has nothing to do with Lenz drag, you seem to worry about cogging but it can quasi completely be elliminated mainly by using odd - even ratio in the rotor - stator poles or possibly with the slant core technology you refer to but Lenz drag remains.  And in general the heavier load you apply to a generator,  the higher the Lenz drag becomes.

Good luck!

[returnedintime]

returnedintime:

Cogging has nothing to do with Lenz drag, you seem to worry about cogging but it can quasi completely be elliminated mainly by using odd - even ratio in the rotor - stator poles or possibly with the slant core technology you refer to but Lenz drag remains.  And in general the heavier load you apply to a generator,  the higher the Lenz drag becomes.

Good luck!

So if I understand you correctly,..you are stating that regardless how cogless a alternator is,...it is still going to have resistance present?