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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Yansi on April 21, 2022, 10:51:58 pm

Title: High voltage transformer for 1kVdc 10mA supply - suggestions?
Post by: Yansi on April 21, 2022, 10:51:58 pm
Hello,

for a project I need a 1kV regulated DC supply, that could deliver at least 5mA, better  10mA output current. For good repeatability of results, I would like to avoid winding diy transformers, so was looking into an option of repurposing a common CFL tube inverter transformers.

These do have specs quite similar as to what I need, as the secondary voltage is usually specified in the range of like 1000 - 2000Vrms, so 1000Vdc after a rectifier would be definitely no problem.  Power-wise, these transformers seems to also fit, as they usually are rated in the range of like 6 - 15W or sort of.

However, I am having trouble finding a source of these transformers, where I could get a transformer including a full datasheet. (currently not in a mood of reverse engineering random Aliexpress transformers).

How many pcs do I need? Say 10-20, likely not more.

The only such transformer available in stock I could find with a spec sheet is this SGE2685-1G from Microsemi (or made for Microsemi? Datasheet attached[attachurl=1]), which seems to be a spare for a LMT3210 TV set. These are available on Aliexpress. But just 7W, I would like to see bit more than that.

Any ideas, where to look for these transformers, where one could locate a specsheet for them?  Found some listed on Digikey (Coiltronics CTX410809-R), however 0 stock, deprecated, not manufactured. Or what other options of transformer to repurpose do I have for this task?

Thanks for ideas.
Y
Title: Re: High voltage transformer for 1kVdc 10mA supply - suggestions?
Post by: moffy on April 21, 2022, 11:23:28 pm
A simple flyback transformer would do the job, especially in that power range. CFL transformers are semiresonant and tend to be specifically to match the characteristics of the tube they are driving.
Title: Re: High voltage transformer for 1kVdc 10mA supply - suggestions?
Post by: Marco on April 21, 2022, 11:31:40 pm
CCFL inverters are more easily available in module form (https://mouser.com/c/optoelectronics/backlighting-components/el-ccfl-inverters-accessories/?function=CCFL%20Inverter). Also a lot of people have used them in the past for kV range power supplies.

Of course CFL inverters are easily available from CFL ;)
Title: Re: High voltage transformer for 1kVdc 10mA supply - suggestions?
Post by: T3sl4co1l on April 22, 2022, 12:04:59 am
That part seems rather small, with the #46 wire.  Voltage should be about right.

How about multipliers, could use a say 20W flyback in reverse?  12V in, 240V out, quadrupled or so.

Tim