# Equation help, Ritchie's page DC Tesla coil capacitor value

#### Tomtom001

Joined Jan 8, 2018
6
Hello!
I am progressing with my project, I now have finished my 240w DC HV power supply. I'm having some trouble understanding a equation on Richie Burnett's site, it should calculate the required value of a capacitor however I cannot managed to use it even for the given example. I'm sure this is a shortcoming of my own but any help will be greatly appreciated in understanding it.
The following is from his site, I'll add a link and the formula as shown.

Design a DC resonant charging circuit to process a maximum power of 8kW. The highest rotary speed will be 500 BPS, and a 10kV DC supply will be used to power the system.
What values of Charging Inductor and Tank Capacitor should be used to meet this specification ?
The tank capacitor value is found by substituting Pmax, BPSmax and Vdc into the second from last equation to get:
Cp = 80 nF
( the equation result is said to be in farads)

https://www.richieburnett.co.uk/dcreschg.html