Romero's experiments and OU principles

[energia9]

This can be built with one solid wire too but we need to use capacitors...
Below are pictures with some of the coils I am going to use in my new project, single wire. Not all are ready, more work to be done.

Hello friend, where can i get these small holeless ferrite beads in the uk?  i have taken out 1 of the same one from an old pc powersuppliy, but, i have looked on ebay maplin and everywhere and i cant get them.. :S

[EMdevices]

@EMdevices .That was a good solid post , full of wisdom ,but there is one point that needs consideration . You quote a frequency of5.76 kHz at 2400 RPM . However there is a sort of concensus that Romero`s machine worked at around 1200 RPM . So, a frequency of 2.88 KHz . Problem is , how did you arrive at that figure . There is a theory doing the rounds that the the "magnetic events" happening at a given coil happen at 8 times  as often as would appear at first glance . This is due to even number of magnets and odd number of coils . If you did not factor this in , then frequency becomes 8x2.88 KHz or 23.04 KHz . and this does not take into account the possible importance of harmonics . So Litz might yet be beneficial . Your comments please?

I did a more complete mathematical analysis in the other tread, but I'll repeat the basic calculation here (assuming all 9 coils are generator coils).



1) As the rotor turns,  every 5 deg of rotation a new magnet and coil align.     (because 360/8 = 45 and 360/9 = 40, so 45-40 = 5 deg difference)

2) So, in one rotation of the rotor,  360/5 = 72 magnet-coil alignments take place   ( these alignments have a higher velocity than the rotor,  somebody posted an animated GIF file showing this phenomena, it's worth seeing.)

3)  Each magnet-coil alignment produces 2 pulses, one positive and one negative,  so 72*2 = 144 pulses per one revolution of the rotor. (because rectification doubles the frequency)

4) So at an RPM of 2400,  we get:   144 * 2400/60 = 5760 pulses per second,   or    5.76 kHz




This was just an example, I realize that he operated at much lower speeds when powered at 4.5 volts.


I agree with the harmonic principles, good point.   However I will say that most of the energy is in the fundamental.


EM

[neptune]

@EMdevices . Absolutely spot on old chap! I am not the world`s best mathematician . However might I point out what may be a small mistake in your maths ? You say that as a magnet passes a coil , it causes 2 pulses ,one positive and one negative . You then proceed to calculate the number of pulses . However , in a Alternating current , one positive pulse followed by one negative pulse equals one cycle . So your final answer needs to be divided by 2 to give the correct frequency , being 2.88 Khz . I realise that this gives even more weight to your original argument against the necessity for litz . Also note the aRomero is using plain wire in his new project , albeit with a cap added . Feel free to correct me if I am wrong on the maths .
Doh ! just realised what you said about rectification doubling the frequency . Sorry .

[EMdevices]

(because rectification doubles the frequency)


neptune,  did you notice the above sentance in my previous post?     His FWBR rectifies the sine wave.  these are pulses into the output capacitor from all the coils.

EM

P.S.   Oh I just saw your edit.   I'm glad you notice it, but good question none the less.

[neptune]

Sorry EM . Failed to spot that!