High Voltage Boost Converter - 24VDCin, 2000VDCout, 0.1Aout - Page 1
Forum section: electronics / projects

author: joebot5
author_rank: Contributor
timestamp: December 18, 2023, 02:50:43 pm
content: Hi everyone,I was wondering if anyone had some thoughts on a circuit design that could take in 24Vdc, and boost to 2000Vdc, and be capable of 100mA of current deliver. This is a project and I can't get into too many details of the application, but wondered if someone has any leads on potential solutions.Thanks

author: PartialDischarge
author_rank: Super Contributor
timestamp: December 18, 2023, 03:24:24 pm
content: Get your hands on one of these (or similar) and reverse engineer ithttps://www.ebay.com/itm/382446669805

author: Slh
author_rank: Regular Contributor
timestamp: December 18, 2023, 04:36:29 pm
content: I'd be looking at a flyback if making it from scratch. Might be a bit on the large side at 200W but should be doable.Definitely looking at SiC output diodes. You might need an auxiliary output to power the feedback amplifier (or just an isolated recom type dcdc brick).

author: PCB.Wiz
author_rank: Super Contributor
timestamp: December 18, 2023, 10:01:55 pm
content: Quote from: joebot5 on December 18, 2023, 02:50:43 pm200W is decent, but not massive, so it should be possible.The large ratio here, would likely require a two stage design.

author: Benta
author_rank: Super Contributor
timestamp: December 18, 2023, 10:15:42 pm
content: For a 200 W flyback, the core will be massive. Which is not a bad thing, as your secondary winding-to-winding isolation will be your main problem, no matter which topology you choose.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 19, 2023, 06:57:33 am
content: Flyback or resonant, yeah. Flyback itself can be square-pulse, quasi-resonant or active-clamp. Resonant (push-pull LLC?) would also be doable, and maybe something more unusual like current-fed push-pull.The main restriction is, because Zo is ~200 ohms, it's relatively high (transformer windings tend to be in the 50-100 ohm range), so capacitance will dominate. Not too badly at all, this is a pretty modest ratio -- but it's worth consideration. Likewise, the output diodes' capacitance, which might be low 10s pF, reflects as much more from the primary side. So you tend to want a simple cap-input rectifier here, as opposed to like a forward converter's choke-input filter. And a forward converter would need higher Z still (generating say 2500 or 3000V at the secondary, to be filtered down to 2000V DC), further discouraging it.Direct boost is a terrible idea because there are few transistors to even make 2kV from; a tapped boost winding could be used, but you might as well go for the transformer to get a little more design freedom -- and isolation if it helps.Don't underestimate safety, obviously, but EMI either: even just touching wires to the output, without closing a circuit, emits a 2kV ESD impulse. Let alone fault conditions (shorting). Common ground, or isolation, may both be good strategies to deal with it; either way, that current and EMI is going somewhere, and it needs to avoid active circuitry.Tim

author: LaserSteve
author_rank: Super Contributor
timestamp: December 19, 2023, 06:23:36 pm
content: Sounds remarkably like a Helium Cadmium laser power supply. Usually about 2200 V at 60 mA for the longer tubes.. Drops to 1800 or so once the cadmium melts. You might hit Ebay for a HeCad supply by Liconix or Omnichrome, maybe a Kimmon.Your after the flyback transformers, usually two per PSUSteve