I have a spare flywheel and have bought enough magnets to cater for 10 magnets either side so that is not an integral factor of 4 so this should minimze ripple they arrive monday need to get more super glue!! thinking of re installing a coil at the opposite side of the machine although space is tight might not be pheasible, I can but try... no not pheasible on this prototype got to work with what I have at the moment!
might get to work with more sturdy materials soon wood screws brackets so then I will be able to mount the coils more geometrically sound for my need but in the mean time I'm working with eight so that I can try to parallel either side of the machine!
so I just wound quite a big coil 0.7 mm 500 gram 142 meters didnt count the turns going to fit it asap and see what voltage it produces got to fit it and see how many volts it produces it's a fairly big coil to be fair wound round a bolt it's thicker than the 54ohm coils but I didnt think that the difference i resistance would be quite so dramatic
Here you go, assuming the 120 degree offset:
The generated voltage using the four 54 Ohm coils arranged as two pairs depends a lot on load, as the traces below show :
In practice, allowing for an ~85% efficient inverter, the power required from the generator will be ~18W, so even with the present coils parallelled it doesn't look possible to provide that unless your wheel rotates at an alarmingly high speed.
The generated voltage using the four 54 Ohm coils arranged as two pairs depends a lot on load, as the traces below show :
In practice, allowing for an ~85% efficient inverter, the power required from the generator will be ~18W, so even with the present coils parallelled it doesn't look possible to provide that unless your wheel rotates at an alarmingly high speed.
Is this taking into account the 50 ohm of the resistance of the coils? nevermind says 27! what is the 50m part and what is (v) for on the what is (a) and (f) nad what is (pp) and (del) going to measure the voltage of the new 7 ohm coil and see what it puts out!
Ohm's Law. 100 Ohm load means less current draw, hence less voltage drop across the internal resistance of the coil.
so my new coil produces 14volt from the raw ac and out of the rectifier 28volt BUT it's only 7 ohm tell me your thoughts on this!! thanks can I compound the voltages if I made three more coils exactly the same and on the next wheel put 10 magnets either side and all in phase (no offset)
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Exactly. But your fan is rated 15W. Allowing for inefficiencies in the inverter, you would need the generator to give you about 18W.
Output voltage of a coil is proportional to rate of change of flux, hence wheel rotation rate. My sim was based on an assumed 40V peak out for a 2000 rpm speed, hence a conversion factor cv = 40 / 2000 = 0.02. Your mileage may vary.
I don't get what you mean by this?
is it possible to add the outputs of the coils? in series and does a say north have to be passing the coils at the same time? and then add and compound the coils from the front and back the two on the front would be in series Vtotal=28V+28V=56V
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