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How can you charge a capacitor bank from 9v without a flash circuit from a camera? Answered

I need to charge a capacitor bank but the only easy way i can fid is to use the flash circuit from a camera. Here in Aus these are hard to obtain and i really need a portable and reasonably cheap Capacitor charger for a project. Please help me, any links to sites i can buy materials for a charger and especially circuit diagrams. Thank you.

6 Replies

oldmanbeefjerkyBest Answer (author)2012-04-18

there is an extremely simple but also unreliable method of charging a capacitor bank.
Asuming your charging 330v caps from cameras, what you can do is find yourself a nice inductor (coil of wire wound around a toroid ring or ferrite), if you have the measuring equipment go for one rated at about 100-200uH, otherwise, one from a pc ATX would have to do. from a PC ATX power supply you want the coil with only 1 wire wound onto it.

next, what you do is, get yourself a 555 timer, or anything which can generate a signal at a changeable frequency (555 is best), for 555's this is called astable mode.
use the 555 timer to switch a mosfet on and off.

what you want, is for when the mosfet is on, 12v is shorted through the inductor and capacitor, when off, the inductor will release a short burst of high voltage, and ill be forced to charge the capacitor.

Look up the 500v dc-dc charger on instructables, and make a schematic based on the simple diagram of how it works. use an IR f or p 460 mosfet, and a decent heatsink. Once you get hte hang of it, you can perhaps try adding a voltage comparator to switch it off when its done charging.

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RichitwillbeA (author)2016-07-25

What I knew from portable X Ray machine from Philips Practix 100 or 160plus and Siemens Polymobile Plus, there are circuit diagram and you can search and download and copy the system for your reference. very interesting, Philips using 19,000 UF x 12 pcs of electrolite capacitor bank for X Ray power 16KW, Good luck.

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steveastrouk (author)2010-03-14

You can build your own fly-back transfomer based charger from off the shelf (or scrap bin for the TV flyback transfomer)  parts, or you can use something like a Maxim MAX8685 chip, if you can get it.

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Doddity (author)steveastrouk2010-03-15

Hey thanks. If you know any can you post any links? I only just started and i waded through random unrelated google guesses for two hours because i didnt have any key-words.

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Re-design (author)2010-03-14

You need a charger capable of putting out slightly more than you want the cap's to be charged to.

If your cap bank has any size to it a camera flash charger might take for ever to charge it and will probably burn out before it is charged anyway.  They have a very small work factor built into them.

If you use the 9 v. battery you might get them to 8.5 or 9 volts but that's all. 

I don't think that's what you are looking for is it.  You need to build a power supply capable of putting out the voltage you are looking for in your cap. bank.  It also needs to be powerful enough to supply the amps since empty the bank will look like a direct short so it needs to have some resistance in the circuit.

Google "high voltage power supply schematic" and look thru what you get and see which ones you think you can build.

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