Building a capacitor charger / High Voltage / Forums

Forums

4hv.org :: Forums :: High Voltage

« Previous topic | Next topic »

Building a capacitor charger

1 2 next

Move Thread

LAN_403

guitarlord66

Sun Mar 01 2009, 05:42AM

Registered Member #1805 Joined: Sat Nov 08 2008, 06:29AM
Location:
Posts: 67

My sister smashed her plasma globe so I took it for parts. I know it has a flyback in it and I've heard people charge capacitors with flybacks. How would I go about doing this? Is there anything I can read to learn how? I'm not that great at making circuits I tried making a photo-interrupter for a coilgun once and it didnt work.....

LGIM0180

Proud Mary

Sun Mar 01 2009, 08:14AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

GuitarLord66 wrote ...
I'm not that great at making circuits I tried making a photo-interrupter for a coilgun once and it didnt work.....

We've all built things that didn't work. If you knew what the outcome was going to be, you couldn't call it an experiment...

Dr. Dark Current

Sun Mar 01 2009, 08:17AM

Registered Member #152 Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384

You must rectify it with a HV diode.

If you want to charge low votlage (<2kV) caps, then there are really better ways of doing so than with "flybacks".

guitarlord66

Sun Mar 01 2009, 10:24AM

Registered Member #1805 Joined: Sat Nov 08 2008, 06:29AM
Location:
Posts: 67

Dr. Kilovolt wrote ...

You must rectify it with a HV diode.

If you want to charge low votlage (<2kV) caps, then there are really better ways of doing so than with "flybacks".

Oh, ok then I wont bother looking into it because I want to charge 300v - 400v capacitors. I might need to look into a boost converter, It's just I dont have access to any stores that sell the componants and I caant buy online..... I think I'll stick with camera flash chargers for a little longer.

teslacoolguy

Sun Mar 01 2009, 03:19PM

Registered Member #1107 Joined: Thu Nov 08 2007, 10:09PM
Location:
Posts: 792

Why not make a simple voltage multiplier? A 3 stage should suit you well and it should charge your caps much faster then a camera circuit. Be sure to add a ballasting resistor in series with the caps you are charging or you will run the risk of them overcharging. Also, i don't do this but if you want to play it safe add a 60W lightbulb in series with one of your ac inputs to limit the imput power or the inrush current may trip your breaker or in worst case blow a diode.

Killa-X

Sun Mar 01 2009, 06:59PM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

I'm sorry just to 'smash' into a thread. But I have a similar question.

I'm driving a wallwart backwards off a 555 and my meter says its over 500V out. How can I charge a capacitor? I put a diode bridge on the HV out, and connected that to caps, but oddly I only get 60V. I'm using camera caps atm for fast-instant charge testing.. but still, why? Is there something I'm doing wrong?

Remind me when I get my flybacks next week to use 1 for coilgun :D

My crappy drawing for my current testing.

Marko

Sun Mar 01 2009, 09:24PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Indeed, why are you guys trying so hard to make up a most complex way to charge some capacitors to 325V?

I can't think of anything simpler than a light bulb and a diode in series with mains.

Marko

Killa-X

Sun Mar 01 2009, 09:37PM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

Because you cant find mains in the middle of a field.

most prefer battery powered aka portable!

guitarlord66

Mon Mar 02 2009, 05:40AM

Registered Member #1805 Joined: Sat Nov 08 2008, 06:29AM
Location:
Posts: 67

Yeah, I'm only looking at battery powered capacitor chargers.

Fnord

Mon Mar 02 2009, 02:58PM

Registered Member #2004 Joined: Sat Feb 28 2009, 11:43PM
Location:
Posts: 39

I may not be the best person to answer your question, but a few days ago I made a flyback for charging capacitors from a battery power source.
I've been having problems with higher voltage input, but supposedly I just need a better transistor.

I just ripped the ferrite core from a flyback and wound my own coils on it, using PET(soda bottle plastic) as a coil form.
I used 33 turns on the primary and 750 turns on the secondary, with 13 feedback turns.
The yokes inside a tv are a good source of secondary wire. Try not to damage it when removing them though.

With my crappy setup I can put out maybe 9 watts of power, but it charges up big capacitors to 300V fairly quickly with a 12v cordless drill battery.

I guess you could make a voltage multiplier to run off dc, but I just wanted something to experiment with that was easy to build and didn't involve too many components. So a flyback was perfect. I would avoid ripping the core from your plasma globe flyback, though, as it may make a good hv ac source for future projects. Try to find a fried one.

Edit: might want to watch those secondary turns... mine is producing more voltage than it should.

1 2 next

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob