I have built a 400V nominal, 500V maximum, 4800uF capacitor bank for a linear accelerator experiment. (Capacitor bank and charger are in a containment vessel, rails and feed wires are shielded; standard precautions.) Right now I'm using a pair of 1M Ohm half-watt resistors as bleeders, but it takes about 3 hours to reach safe handling voltages without shorting the rails, which will really slow down the tuning process.
I've thought about using switches to short out sections of a series resistor discharge string as the bank voltage falls to approximate constant power. A string of 4 incandescent light bulbs would also work, I think, but are fragile and fairly bulky.
A constant power electronic load would be ideal, but most of the examples I've found are designed for less than 200V, or are expensive desktop instruments.
Any suggestions?
Thanks!
-Bob