3phase vs 5phase

Ben And Fish, while i am waiting for parts and working on the new turbine, i managed to build a 3 phase and 5 phase.
3 phase VS 5 phase conclusion
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:) bellow is an update to where i am at.
it havs been terrible with snow storms.
things are a bit slow. but moving ahead.

3phase:
1 disc, 24magnets, 10.25"
18coils, 125turns, 18awg, star config
free spinn= 100rpm=>13.5vdc
under 24vdc light bulb load=> 130rpm=13.5vdc
under 36vdc light bulb load=> 122rpm=13.5vdc
under 48vdc light bulb load=> 115rpm=13.5vdc
@45rpm=1.25amp shorted

5phase:
1 disc, 24magnets, 10.25"
20coils, 100turns, 18awg, 5neutral config
free spinn= 155rpm=>13.5vdc
under 24vdc light bulb load=> 187rpm=13.5vdc
under 36vdc light bulb load=> 182rpm=13.5vdc
under 48vdc light bulb load=> 176rpm=13.5vdc
@85rpm=1.85amp shorted

regards

sam

Sam,

I saw your post @ fieldlines, very nice work. I would suggest, since I saw a scope on your tool bench, that you monitor current and voltage to get a better idea of what is happening in your alternators. You are getting results that appear contradictory to me.

For instance, a 12V bulb, 24V bulb and 48V bulb if of the same wattage should have the opposite effect on your RPM/Voltage. If they are in fact all 12V bulbs, and the wattages are 12W, 24W & 48W, then your results track as they should. If the bulbs are not the same wattage and not the same voltage, then really your results are difficult to gauge.

I will try to post some ideas about how to test what you have tomorrow.

Fish

Sam,

To get accurate comparisons of your alternators, you will need to pick a single "light bulb" for your tests. Leave the battery, charger et al out of the loop. Measure the DC resistance of your light buld and compare that figure to the "calculated" resistance:
I
Rc = En^2/Pw

Where:
Rc = Calculated Resistance
En = Bulb's Nominal Voltage (eg 12V)
Pw = Bulb's Nominal Power Rating (eg 100W)

So, if you have a 12V bulb rated at 100W, the calculated resistance should be:

Rc = (12^2)/100 => 1.44 ohms

Compare the measured bulb resistance with the calculated resistance, if they are close (and they should be) you can continue, if not, repeat the process with a different bulb, or check your meter & calculations.

Once you are satisfied with a bulb, connect the bulb to the output of your rectifier. Connect your scope's ground to the ground side of your rectifier and connect your scope's probe to the positive side of your rectifier. Set your scope's voltage range to ~20V/Div; set your scope's time base to ~20mS/Div and start turning your alternator. Adjust your scope's voltage range to get as close to full screen scale as possible. Adjust the time base up or down to get a good shot of each "pulse".

DO NOT connect a capacitor or ANYTHING ELSE to your rectifier! Just the bulb & the Scope.

Measure the length and magnitude of each pulse, and the length of time between pulses. Note the Peak voltage as well as the "Average Voltage". If your scope is a DSO with a "math package" it should do this for you. If it is an analogue scope you will have to do the math. In either case, your current will be your average voltage divided by your resistance, and your output power will be your average voltage * your average current (or Vav^2/Rc).

Next, Connect a capacitor across the output of your rectifier. I would use a 100V 10uF or larger polarized capacitor. Repeat the above test. In this case the capacitor will "filter" your output somewhat and give you a better idea of what your average alternator output is.

PLEASE take some video of your scope for both of the above tests, and report the Rc of your test bulb.

With Regards,

Fish