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       #Post#: 3721--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: happygolucky Date: July 5, 2014, 9:47 pm
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       @ness question on the cap size for booster ...how do you
       determine the size of your vawt an cap to use..... your right
       about meter
       i have variance on 3  of them ..an i use them as a ball park
       tool. i' m only interested in 3  figures the ohms law...amps
       volts an watts. the output @ 60 rpm must be  what it is
       determined on the output of your vawt @ 60 rpm?  is this a
       starting point?a true an tried cut in speed to gauge from? is
       there a  formula, or a guessing game till you get a double
       ,triple or quad spike in voltage..
       i see the 220 uf is tried an true.. Cockcroft–Walton doubler
       was going to try an make one an see what results i get.. or
       yours  i see posted..
       thanks HGL learning is a skill not yet mastered till one knows
       he is right with his quest.
       #Post#: 3723--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: nessprojects Date: July 5, 2014, 10:04 pm
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       Cockcroft–Walton doubler is what the circuit I have given and is
       the same as what lynx sent you except he fitted 1000uf caps
       which are good for about 2 amps.
       If your turbine cuts in at 120rpm then with the doubler it will
       cut in at around 60rpm.
       The values needed for this particular turbine are unknown until
       I can carry out some tests to see what suits it best, there may
       be a formula for it but I do not have one.
       BTW... Ohms law is voltage divided by amps times ohms. The
       formula you will use more is wattage divided by voltage times
       amperage.
       #Post#: 3724--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: happygolucky Date: July 6, 2014, 2:32 am
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       thanks your right i was just in a rage at the moment..to much
       stress. time to take a break.. i am learning  electronics,
       thinks i'am going yo take a few classes an brush up..keep us
       posted.. please
       #Post#: 6183--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: Jona Date: October 15, 2016, 7:11 pm
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       Boost Circuit where can I find the parts list or schematic for
       this awesome circuit.
       Thanks guys.
       #Post#: 6198--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: lynx wind Date: December 22, 2016, 9:26 am
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       Based on Nessprojects schematic for a boost circuit I tried this
       little circuit for 3 Phase with the added feature of a
       controller to stall the turbine at 14.5 volts.  It seems to work
       fine.  Once the battery hits 14.5 two phases are momentarily
       shorted on the AC.  This causes the PMA to drop rpm to about 11
       volts and if it tries speeding back up and the battery is still
       at 14.5 v it stalls again.  This circuit also stalls the turbine
       to about 100 rpm if the battery is disconnected.  If this tests
       well I will add a voltage LCD readout and a turbine stop switch.
       Thoughts, suggestions?
       #Post#: 6199--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: Bassman Date: December 25, 2016, 6:58 am
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       Are you trying to limit rpm or charging voltage?
       If charging voltage is what you want to limit, I guess I would
       use a buck-boost converter where any increase in rpm would
       translated into increasing the  charging current and leave the
       voltage at about 14.5 volts. It would be a challenge to design a
       high current circuit though.
       Also on a three phase stator, shorting just one of the phases
       might burn out that phase.
       #Post#: 6200--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: ethan Date: December 27, 2016, 5:35 am
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       Those squares are bridge rectifiers?
       I can't see how the battery getting to 14.5 feeds back to
       activate the relay. Please show me how it does that.
       #Post#: 6203--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: ethan Date: December 27, 2016, 7:17 pm
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       I had to fill in the boxes , now i see.
       #Post#: 6204--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: lynx wind Date: December 27, 2016, 10:10 pm
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       The boost section increases voltage from 2 phases while the
       third phase is putting out a lower voltage.  I am using 100uf
       caps.  When the boost hits 12.5 volts the battery is getting a
       trickle charge.  On the test VAWT this occurs at 7-8 mph wind
       speed.  Once winds reach 11-12 mph the full three phase kicks in
       and the boost is bypassed.  The diode leading from the relay
       back to positive protects the circuit from bleeding current
       through the relay's coil.  Only when battery voltage approaches
       14.5 volts is there enough current to activate the relay and
       short the two phases - slowing the turbine.  This occurs very
       fast as a short blip.  The turbine slows to about 11 volt
       output.
       On the test VAWT I have up the winds need to be about 8 mph
       steady before charging occurs and the VAWT is turning at 260 rpm
       - a TSR of 2.0.  I am using 150 turns 20awg wire for a total
       resistance of 2.0 ohms.  The coils are 3/8" thick.  I am going
       to change this to 200 turns - 22 awg and 1/4" thick coils.
       Resistance will go up to 4.4 ohms but cutin will occur at a
       lower speed.  It is a fine balance between resistance and
       performance.  It could be 21 awg, and 170 turns would be better.
       Profiling this VAWT is helping to confirm that the B or magnetic
       flux through the 3/8" thick coils is a fairly low 0.25.  Using
       thinner coils and stronger magnets will get B back to .35-.37
       If the PMA used a dual plate, flux B would go up considerably
       and lower resistance wire could be used.  A dual plate PMA is a
       tricky thing to make for a DIY plan.
       #Post#: 6209--------------------------------------------------
       Re: NessProjects Boost Circuit
       By: Bassman Date: December 29, 2016, 7:15 pm
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       Just a observation. When the relay contacts close, then open
       again a high voltage pulse is generated by the stator coils
       field collapsing.  Check it with your oscilloscope. Since
       rectifiers would also short out the alternator maybe a snubber
       capacitor across the contacts might tame the spike. Or maybe the
       caps in the doubler can do the job.
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