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voltage multipliers Re: High amperage in tank circuit



Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

 > Finally, could someone point me to a link which explains the theory behind
 > a voltage multiplier?  I have been checking like crazy, and can't find an
 > explanation that I can understand.  It's hard for me to grasp the concept
 > of diodes and capacitors multiplying voltage.

Search for "Cockroft Walton" and there are some nice animated web sites that
show what's going on.

Draw a diagram of the multiplier and imagine the diodes as switches arranged
in two sets that are alternately closed (on positive and negative halfcycles
of the input).

Referring to the picture on my web page at
http://home.earthlink-dot-net/~jimlux/hv/cw1.htm , it works like this...

On the negative half cycle, D1 is on, D2 off, etc.  C1 charges up to Vpk,
with the polarity such that the positive end is towards the stack.  On the
positive half cycle, D1 is reverse biased, so off, and D2 is now on, with
the voltage at the junction being the sum of the transformer output voltage
and the voltage on C1.  Current flows through D2 into C2, eventually
charging it to 2*Vpk. On the next half cycle, C1 charges up again.

The same mechanism gradually moves charge up the stack, as the capacitors on
the left hand side get moved up and down in voltage, relative to the
capacitors on the right hand side. It's sort of like a bucket brigade.