High-voltage power supply (50KV) - Page 1
Forum section: electronics / testgear

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: November 21, 2017, 12:39:42 am
content: I am designing a cheap 50kv power supply. It only needs to supply at maximum 5 watts. Can I use something like this kit:https://www.ebay.com/itm/15KV-High-Voltage-Inverter-Generator-Spark-Arc-Ignition-Coil-Module-DIY-Kit-3-7V/382131734381?epid=564952796&hash=item58f8d3876d:g:aAsAAOSw-89ZRPh7in conjunctions with a voltage multiplier made with 20kv 10nf capacitors and high voltage diodes? Thanks

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: November 21, 2017, 12:14:32 pm
content: Wups, wrong thread.

author: floobydust
author_rank: Super Contributor
timestamp: November 21, 2017, 09:18:46 pm
content: For under $2 that is a great chinese bargain.A one-transistor oscillator kit with PCB, switch, flyback, NPN transistor TO-126 (some pics lie and show TO-220 2SD880) and heatsink.OP where is your thread going?

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: November 21, 2017, 10:37:33 pm
content: Testing x-ray emission from old rectifier tubes. Current limiting resistors will be used. I'll make a proper thread in the right section when this gets started. I just need to know if it will work with a voltage multiplier with capacitors of that value.

author: BU508A
author_rank: Super Contributor
timestamp: November 21, 2017, 11:18:24 pm
content: Maybe you'll find this website useful:http://highvoltageshop.com/epages/b73088c0-9f9a-4230-9ffc-4fd5c619abc4.sf/de_DE/?ObjectPath=/Shops/b73088c0-9f9a-4230-9ffc-4fd5c619abc4/Categories/3/Seite__Kategorie1Sorry, most parts are in German but I think you'll get the idea.

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: November 22, 2017, 02:48:24 am
content: Nope, they don't ship to the US.

author: floobydust
author_rank: Super Contributor
timestamp: November 22, 2017, 05:55:45 am
content: If you are at 40kV or 65kV, is that a problem, to have poor regulation?I think the hard part will be controlling the output voltage - this runs off 3.7VDC but rated to 12VDC power (with some smoke me thinks). I would be tempted to instead use an IC SMPS/oscillator and measure the output voltage to regulate things, but HV gigaohm resistors are expensive and huge.Wonder if 15kV is absolute max. this can generate, it seems to be the transformer's insulation limit.So you could take <10kV and a 6-stage multiplier. Sometimes it's cheaper to use more multiplier stages than the higher voltage rated parts.The2CL77 HV rectifier diodeslook good, 20kV 5mA 100nsec. and cheap on Ali $0.25 each. 20kV 10nF disc caps are $1.12 ea.

author: BU508A
author_rank: Super Contributor
timestamp: November 22, 2017, 06:08:09 am
content: Quote from: AutogolazzoJr on November 22, 2017, 02:48:24 amThey have a shop on ebay where they state, that they will ship worldwide:http://stores.ebay.com/highvoltageshopc0m/https://www.ebay.com/itm/Hochspannungskaskade-25kV-Hochspannung-Villard-high-voltage-multiplier-module-/281697255143?hash=item419676fee7#shpCntId

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: November 22, 2017, 11:36:53 pm
content: Probably too expensive. Will the kit i linked at the beginning work with a voltage multiplier for low-wattage?

author: floobydust
author_rank: Super Contributor
timestamp: November 23, 2017, 07:04:24 am
content: Yes, I would say that kit is good to connect to a HV multiplier and make 50kV at a couple watts.I don't know the operating frequency and the kit has a small transistor and small heatsink so that will limit power output. 5W out (50kV 100uA) might heat it up too much.

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: November 23, 2017, 08:23:21 pm
content: Should be fine, I will use a large heatsink and dunk the entire thing in oil

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: February 17, 2018, 11:58:57 pm
content: Sorry to start up this old post, but I still need help. I fried two of those 15kv kits before i built the 10x cascade, so can't try that out yet.What i need right now is some way to generate 10 or so watts at 5kv high frequency ac to run into the cascade. What I would really like to get my hands on is an ac flyback and a zvs driver, but I can't find an ac flyback anywhere. Do I have to wind one by hand, or any cheaper way to do it? Will those tiny 15kv ebay kits do?Thanks

author: ahbushnell
author_rank: Frequent Contributor
timestamp: February 18, 2018, 12:07:52 am
content: Quote from: AutogolazzoJr on November 21, 2017, 12:39:42 am>50 kV with vacuum can make a bunch of Xrays. I worked on a project at 65 kV and you have to be careful. I hope you know what you are doing. Do you have equipment to measure the radiation? Do you know how to design shielding?

author: IanB
author_rank: Super Contributor
timestamp: February 18, 2018, 12:19:10 am
content: Quote from: AutogolazzoJr on November 21, 2017, 12:39:42 amI can't help observing the length of the insulators, the size of the bushings, the thickness of the insulation, and the air gap clearances used in 30-60 kV power distribution systems. 50 kV does not like to be confined or contained.I am inclined to think that any small scale 50 kV generator is also going to be a "self-destroying device". If you try to make 50 kV it is going to destroy the thing that tries to make it.Quote from: AutogolazzoJr on February 17, 2018, 11:58:57 pmCase in point. If the 15 kV devices destroy themselves, how can you hope to get up to 50 kV?

author: ahbushnell
author_rank: Frequent Contributor
timestamp: February 18, 2018, 12:25:29 am
content: Quote from: IanB on February 18, 2018, 12:19:10 amThat's a good point. 50 kV can be done in air but it takes some care. (and corona rings).A voltage multiplier is probably a good approach.

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: February 18, 2018, 03:30:40 am
content: It's been done before. The 15kv kits fried because of the heatsink was too small. I already have a multiplier but need a zvs driver and ac flyback to complete it. The entire thing will be in oil. Any help please?

author: ikrase
author_rank: Regular Contributor
timestamp: February 18, 2018, 05:26:33 am
content: Of course, there's also the question of a 40kV plus500 Wpower supply for cheap. I would be interested whether anybody has any options there.

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: February 18, 2018, 02:46:24 pm
content: Not needed here. All I really need now is an ac flyback. Cheapest way to get one?

author: AutogolazzoJr
author_rank: Regular Contributor
timestamp: February 18, 2018, 09:06:20 pm
content: https://www.pocketmagic.net/wp-content/uploads/2009/07/dualflyback.jpgHow bad of an idea is this?

author: floobydust
author_rank: Super Contributor
timestamp: February 18, 2018, 11:13:26 pm
content: A car ignition coil works fine, they are around 1:85 turns ratio and you don't need many multiplier sections at all.