Pseudonymous YouTuber "Advanced Tinkering," hereafter simply "Tinkering," has built an adjustable power supply with a difference: this one covers a voltage range from 20,000V up to 50,000V.
"I've wanted to build a high-voltage power supply for a long time," Tinkering explains of the project, which goes above and beyond most benchtop power supplies by providing double-digit kilovolts for high-voltage projects. "Using a ZVS driver, a flyback transformer, and a high-voltage cascade, I generate a voltage of 50 thousand volts."
As Tinkering says, the do-it-yourself power supply design is based on a zero-volt switching (ZVS) driver, which connects to a flyback transformer — a component which will be familiar to anyone who ever dismantled a cathode-ray tube (CRT) display. The ZVS' high-frequency switching output goes into the flyback transformer on the primary side, with few windings, and comes out of the secondary side, with a lot more windings, considerably boosted.
With just those two components, Tinkering has an impressively high-voltage supply — demonstrated arcing between two bared wires and measuring at up to 15,000V. "That's, of course, not nearly the 20-60,000V I want to achieve," the YouTuber notes, meaning a few more parts are required: a step-down converter for adjusting the supply to the flyback transformer and a Cockcroft-Walton multiplier — designed back in 1932 to power a particle accelerator responsible.
"I need an AC [Alternating Current] output from this transformer," Tinkering adds. "To build the voltage multiplier I bought these 50kV 1nF capacitors and these 100mA 30kV diodes. These multipliers can be used, as the name suggests, to multiply your voltage — with enough stages you can get to insane voltages, like 200,000V, but of course we will trade off some current for the increased voltage."
Fully assembled, with various components potted in epoxy to prevent dangerous arcing and with a handy low-voltage direct current (DC) output added to the overall design, the finished power supply proved capable of delivering 50,000V — slightly below the 60,000V target, but still impressive. "I should probably mention," Tinkering admits, "that I'm far from an expert regarding electronics, so this video is not meant as a tutorial and you should always do your own research when it comes to your own safety."
More information is available in the video embedded above and on the Advanced Tinkering YouTube channel, though as Tinkering warns high-voltage electronics should always be treated with care.