Future High Voltage DC Power Supplies of the Shielded Design

A large number of research laboratories are now using stabilized 600 kV dc power supplies of the entirely shielded design, with electronic ac supply and feed-back control systems.1 Recently, a new 600 kV power supply with a rated current of 20 mA has been marketed. At the present time, 1 MV dc power supplies which will operate in aluminum vessels under pressurized sulphur hexafluoride gas insulation are being constructed. The standard models have an overall stability including ripple voltage and noise of 1 part in 1000, both for continuous and pulsed operation.