TO: Kadora
Well, that's true. One solution is making higher V than you need
then using the V divider for the V & I you want. The V drop across
the current limiting resistor is minimal if your shunt across the load
is big, say 1 Megohm. Remember, it's the
ratio between two R's
in a voltage divider. You can use any size resistors you want as long
as you maintain that ratio.
...or you can use a capacitor to limit current, which you may know
are transparent to AC. Check out the circuits at:
http://www.geocities.com/CapeCanaveral/ ... 2/hv2.html
There was a young man on this board last year, Marcus Wagner,
quite bright with circuits, was offering a pulser board. He knew how
to use capacitors much like transformer coils to get various
current ratios / differentials, the point of the capacitor(s) to
regulate current flow. (A smaller capacitor lets less current
through.)
Here are a couple links on PWM:
http://www.uoguelph.ca/~antoon/circ/pwm555.html
http://www.allaboutcircuits.com/vol_6/chpt_6/9.html
Forget about DC flow for the moment because you need to create
AC oscillations for any kind of pulse train. Once you establish the
current flow and frequency you want, CLAMP it above the zero line.
You get DC pulses out your clamper. One clamped pulse equals both
half-cycles of a sine wave. Note: clampers are also known as voltage
doublers. They use a diode, and a capacitor. I think you can only
do this on the primary, low V side, because I've never seen a MOSFET
that could gate 30-60KV.