[Amps] Capacitance Amount Formula

[jeff millar]

This is a ripple calculation based on the basic capacitor formula

    I = C * dV / dT

Let's say you want 3% ripple at 4 KV...that's 120V.  The capacitor charges
on each line peak, twice in each 60 Hz cycle, or 8.3 msec.  Rearranging

    C = I * dT / dV

Plugging in

    C = 0.5A * 8.3 ms / 120V = 35 uFd

jeff, wa1hco

----- Original Message -----
From: "Rick Cole VK3YM" <vk3ym at iprimus.com.au>
To: <Amps at contesting.com>
Sent: Sunday, February 09, 2003 12:08 PM
Subject: [Amps] Capacitance Amount Formula



When designing a HV PSU is there a reccomended formula for determing the
total amount of capacitance required in the filter..
I have not seen much discussion on this subject and now I am about to design
and build a 4kV supply @ 500mA and am just interested in what would be a
good amount of capacitance to use for this design..
I have studied many designs that are available but no-one seems to give the
required information as to why they used the amount they did in the design..

           Regards  Rick




It is the soldier who salutes the flag,
serves under the flag
and who's coffin is draped by the flag,
who allows the protester to burn the flag.

_______________________________________________
Amps mailing list
Amps at contesting.com
http://lists.contesting.com/mailman/listinfo/amps