how do i convert 220VAC to 220VDC? - diyAudio
Go Back   Home > Forums > Amplifiers > Power Supplies

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 13th September 2010, 03:13 PM   #1
coolfox is offline coolfox  Europe
diyAudio Member
 
Join Date: Sep 2010
Default how do i convert 220VAC to 220VDC?

i'm trying to drive my eht transformer with 220Vdc which sounds crazy i used bridge rectifier with 1N4007 to regulate network and a filter capacitor about 100uf/400V.. isn't that true?at the end of this line i must get it ? could you please explain me clearly how do i get 220V DC from network[help=?][/help] i'm stuck!
  Reply With Quote
Old 13th September 2010, 05:45 PM   #2
diyAudio Member
 
Join Date: Mar 2010
First, you can't drive a transformer with dc. Second, if you connect a rectifier and capacitor, you will get the peak voltage (without load) and that will be the rms ac voltage times the square root of two, so you get from 220 Vrms over 300 Vdc.

If you attempt to put dc into a transformer winding, the core will saturate and you will get a very high current, and probably burn out something. Or cause a fire.
  Reply With Quote
Old 13th September 2010, 06:23 PM   #3
BrianVG is offline BrianVG  Belgium
diyAudio Member
 
Join Date: Jun 2010
Location: Louvain
Transform to 157V then recitifie it. You'll get about 220V.
DC is 3 times more dangerous than AC THERE IS NO CHANCHE TO LET THE POWER CORD GO ONCE YOU TOUCHED IT!
I won't recommend to use such DC voltages. For instance you need about 10kVDC to make an arc of 3cm. But only 220VDC to do the same
__________________
FET fanatic
  Reply With Quote
Old 13th September 2010, 06:31 PM   #4
macboy is offline macboy  Canada
diyAudio Member
 
Join Date: Oct 2003
Location: Ottawa, Canada
Quote:
Originally Posted by coolfox View Post
i'm trying to drive my eht transformer with 220Vdc which sounds crazy
No, that doesn't sound crazy.
It is crazy.
You need to study and learn a lot more before you do something stupid and kill yourself. The questions you asked show how little you know about this stuff, so maybe playing around with high voltages (high DC voltages in fact) is a bad idea.
  Reply With Quote
Old 13th September 2010, 07:04 PM   #5
coolfox is offline coolfox  Europe
diyAudio Member
 
Join Date: Sep 2010
i dont drive directly the eht with DC..there is a 555 trigger on the network line driving the ırf830 mosfet's Gate and the primer winding of the eht transformer is to the mosfet's Drain..yes there is about 300Vdc on the drain and i can't drive the mosfet still.. i succeed that when i give about 128Vdc to drain and give the 555 's supply voltage externally..i don't expect to extend the cm too much(may be 6 cm) but though i couldn't make it , this plug/jack structure sounds me practical..
  Reply With Quote
Old 13th September 2010, 08:03 PM   #6
BrianVG is offline BrianVG  Belgium
diyAudio Member
 
Join Date: Jun 2010
Location: Louvain
I just don't get what you want to do. A 555 is a counter wich only needs 16Vdc? Primary winding of the transformer is 300Vdc? Do you understand how a transformer works? The there is a magnetic flux created between the two windings wich is only possible with alternating currents. This way you are heating your transfo. If you do this for to long the insulation will start to melt and not much later you'll end up with a fire.
__________________
FET fanatic
  Reply With Quote
Old 13th September 2010, 09:01 PM   #7
coolfox is offline coolfox  Europe
diyAudio Member
 
Join Date: Sep 2010
ofcourse i know how a transformer works..my circuit is a simple flyback driver circuit with 555.. i use the 555 as an square wave generator in a eht's desired spec. at low levels. 555 generates ttl and this is connected to mosfet's gate.. mosfet creates an alternate at the eht's primer..then transformer works..
in my first test i used an external supply ;about 12Vdc for 555 and 128Vdc to" mosfet drain" (i said eht before,sorry..).. this works very well..there is an 3-4 cm arc..
then i tried to drive 555 over network . i regulated with bridge rectifiers and reduced the voltage with and power resistors and used filter caps to minimize peaks to 14Vdc ( i think there is a problem) .. this structure works on its own..
lastly i try to get 220Vdc (which is about 300Vdc) after the bridge rectifier and filter capacitor to mosfet drain.. from that point nothing works ...
  Reply With Quote
Old 14th September 2010, 09:46 AM   #8
diyAudio Member
 
Join Date: Feb 2010
Location: Bucharest
Send a message via Yahoo to Th3 uN1Qu3
He isn't going to kill himself with a flyback transformer, but he may kill himself when the transformer dies and there's 230v all over the place. Anyway, all it takes is a bridge rectifier and a capacitor. BUT i wouldn't run anywhere close to 300v DC into your typical flyback transformer. You're going to kill it as soon as you plug it in. I'd run 100 volts at the very extreme, it's best that you don't go over 40v if you want that transformer to survive for any reasonable length of time.

Anyway, here's why your circuit does not work. When wiring a bridge rectifier to the mains you will still have phase on one of the leads (depending what orientation you plug it in), meaning everything may be floating 230v above ground, which is NOT a good idea.

You need isolation between the 555 and power MOSFET. For best results drive a smaller mosfet with the 555 and have that output into a drive transformer from an old ATX power supply. At the other side of the transformer you wire your power MOSFET. This should work, but again, i wouldn't run it straight off the mains, you will damage the high voltage transformer.

@ BrianVG: AFAIK 50Hz AC is more dangerous than DC, i'll try to remember where i read that.
__________________
"Audio grade" components simply means that they failed at a more critical job.
  Reply With Quote
Old 14th September 2010, 11:07 AM   #9
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
AC more dangerous because it disrupts your cardiac rhythm?

DC more dangerous because it makes your muscles contract and force you to hang on to it? I believe there used to be an old technician's trick (DON'T TRY THIS AT HOME) of touching a potentially live DC circuit with the outside of a finger (i.e. the side with the fingernail) so that the resultant muscle twitch (if it was live) would pull the finger away - much safer than touching with other side and grabbing the circuit.

Oh, and RF will give you a nasty deep burn which takes months to heal.
  Reply With Quote
Old 15th September 2010, 08:19 PM   #10
diyAudio Member
 
megajocke's Avatar
 
Join Date: Jan 2003
AFAIK 50Hz AC will also make you unable to let go. That combined with that it is more likely to upset your heart rhythm makes it much more dangerous than an equivalent DC source.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Smps 220vac / 13.8vcc For 100a albert_emule Power Supplies 13 14th July 2009 01:17 AM
220VAC to 12VDC conversion ioanno Class D 1 21st December 2004 12:24 PM
Plus biasing heater (220vdc above ground) Bas Horneman Tubes / Valves 7 24th February 2003 02:32 PM
I Have a big problam !!......with Inverter 12VDC to 220VAC Dj BASS AMP Solid State 27 23rd August 2002 09:14 AM


New To Site? Need Help?

All times are GMT. The time now is 11:35 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2