[Amps] Capacitance Amount Formula

[Rick Cole VK3YM]

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




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