+-114V 1.8KW SMPS Schematic - 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 28th November 2009, 11:34 AM   #1
Account Disabled
 
Join Date: Oct 2008
Default +-114V 1.8KW SMPS Schematic


Hello

Attached is a schematic for a SMPS from a known power amplifiers manufacturer, it should deliver 1.6KW to 1.8KW


Comments are welcomed.

Any one intrested into more schematics, mail me.


Micro
Attached Files
File Type: zip SMPS_SH.zip (198.3 KB, 3274 views)
  Reply With Quote
Old 1st December 2009, 11:21 PM   #2
Matt BH is offline Matt BH  United Kingdom
diyAudio Member
 
Join Date: Jul 2009
Location: Cheltenham
Are you thinking of buiding it? It looks pretty similar to this:
A Kilowatt Switching High Voltage Power Supply
Nice. Im interested because Im building a TIG welder along similar lines. I also have six 48V 30A telecomms PSUs that use a very close circuit but have active power factor correction.
Cheers Matt.
  Reply With Quote
Old 2nd December 2009, 07:42 AM   #3
Account Disabled
 
Join Date: Oct 2008
Quote:
Originally Posted by Matt.B.H. View Post
Are you thinking of buiding it? It looks pretty similar to this:
A Kilowatt Switching High Voltage Power Supply
Nice. Im interested because Im building a TIG welder along similar lines. I also have six 48V 30A telecomms PSUs that use a very close circuit but have active power factor correction.
Cheers Matt.


Your Becnh is amazing, I liked it, Also your project construction is amazing,
I am in the process of building this supply for Audio Amplifier.
  Reply With Quote
Old 2nd December 2009, 03:06 PM   #4
Eva is offline Eva  Spain
diyAudio Member
 
Eva's Avatar
 
Join Date: Oct 2003
Location: Near the sea
Send a message via MSN to Eva
Quote:
Originally Posted by Matt.B.H. View Post
Are you thinking of buiding it? It looks pretty similar to this:
A Kilowatt Switching High Voltage Power Supply
Nice. Im interested because Im building a TIG welder along similar lines. I also have six 48V 30A telecomms PSUs that use a very close circuit but have active power factor correction.
Cheers Matt.
This looks a lot like the prototypes that I were doing several years ago before I got into double sided PCB, SMD and careful control of parasitics. It's built like a 100KW supply but only intended for 1-2KW. Connecting things with wires point to point is ok for switching frequencies below 5Khz with slow semiconductors and low di/dt and dv/dt slopes, it's how industrial inverters are done.

But at higher frequencies, higher di/dt and dv/dt slopes are required for good efficiency, but they are not achievable reliably with wires and a point to point scheme because parasitic voltage spikes appear everywhere increasing stress on power transistors and diodes and ultimately causing the circuit to disturb itself due to EMI and fail.

The voltage drop across an inductor is V=L*di/dt. This rule applies to the parasitic inductances on every wire, PCB track and on every component lead too. For example, in the class D amplifier that I'm finishing I use the parasitic L*di/dt drop across the source leads of the MOSFET to control turn on di/dt. The gate drive circuit does not allow 3V of drop to be exceeded on approx. 4nH, which translates into approx. 750A/us turn on slope. In other words, 66ns to start conducting 50A in each MOSFET, which nowadays is not crazy fast at all. Parasitic inductance of the source lead of a TO-220 case should be 7.5nH, but lead length and mounting style also counts a lot (the front side of the transistor is facing a ground plane too).

Note that, in a MOSFET or IGBT, the parasitic L*di/dt voltage drop across the source lead (and source PCB track or wire, every path shared with gate driver loop) appears in series with gate drive voltage. What could be the effect of this when connecting transistors with long leads to the PCB? (Particularly when you are not considering at all the parasitics involved in what you are doing ) I blew many transistors that way.
__________________
I use to feel like the small child in The Emperor's New Clothes tale

Last edited by Eva; 2nd December 2009 at 03:12 PM.
  Reply With Quote
Old 3rd December 2009, 11:28 PM   #5
Matt BH is offline Matt BH  United Kingdom
diyAudio Member
 
Join Date: Jul 2009
Location: Cheltenham
Its not my bench:-) and yes it is a bit wrong. especially the way he has the gate drive transformer located two feet away using twisted up telephone wire.

Just thought I would post it, he does give a good run down of the way he got over the problems. I am sure there are still many.

I recently got hold of a massive transistor stack capable of 400 or so amps. This thing is wrong. It at least uses current sharing resistors (they are darlingtons 1990 style) but each row of trannys is connected to each other in turn rather than a nice star type arrangement. Good job it was a prototype and has never been used:-)
It will after being reconfigured make a nice half bridge for my TIG welder project. I am glad I got it as the price of a pair or even multiple IGBTs to make up 200A or so is very expensive. Plus this will not see much over 400Hz so parasitics should not be a problem. This does not mean that I wont design it accordingly.

Micro, If you are serious about building a switcher start with a smaller one. Modify an old PC supply and play about. At least its cheap. At the >1Kw level you start getting into expensive semiconductors and one blow up is enough to ruin a project and it will blow up. Switchers are hard to design and build, read as much as you can. Many of the application notes by the suppliers are more useful than stuff on the general web, but most of all build something smaller along similar lines first.

Cheers Matt.

Make sure you use an isolation transformer!!. Also watch out for the input caps. 380 odd volts will kill. Keep safe.

Last edited by Matt BH; 3rd December 2009 at 11:39 PM. Reason: caution
  Reply With Quote
Old 3rd December 2009, 11:38 PM   #6
Account Disabled
 
Join Date: Oct 2008
Cool OK

Quote:
Originally Posted by Matt.B.H. View Post

Micro, If you are serious about building a switcher start with a smaller one. Modify an old PC supply and play about. At least its cheap. At the >1Kw level you start getting into expensive semiconductors and one blow up is enough to ruin a project and it will blow up. Switchers are hard to design and build, read as much as you can. Many of the application notes by the suppliers are more useful than stuff on the general web, but most of all build something smaller along similar lines first.

Cheers Matt.
Thanks for the note. and I already played with half bridge 900W, and blow up about 50 Mosfets, and already I worked into fixing SMPS for amplifiers for 12 years, and I know what I am doing, so don't worry

I am no longer working at the 2KW SMPS alone (since I need a lot of information's cannot find for free), there are 2 engineers engaged into this project (Fully PAID), I don't think I will fail, since this project will cost about 3000 US$ between parts and design

The transformer designed at percussion-Inc, PCB in India. All parts from RS.
Why not to make that supply reality?

It should work


Last edited by microsim444; 3rd December 2009 at 11:47 PM.
  Reply With Quote
Old 4th December 2009, 09:53 AM   #7
luka is offline luka  Slovenia
diyAudio Member
 
luka's Avatar
 
Join Date: Sep 2005
Location: in Slovenia :)
Send a message via Skype™ to luka
blow up about 50 Mosfets?
how come I did 1kw+ a long time ago, but didn't blow no fets, and I could say I had no idea what I was doing at first?

What is your supply for? will it be commercial product?
  Reply With Quote
Old 4th December 2009, 11:17 AM   #8
Account Disabled
 
Join Date: Oct 2008
Quote:
Originally Posted by luka View Post
blow up about 50 Mosfets?
how come I did 1kw+ a long time ago, but didn't blow no fets, and I could say I had no idea what I was doing at first?

What is your supply for? will it be commercial product?


Yep. That was because my first supply is the STUPID A&T Labs power supply.

but in my 900W Half bridge, about 10 due my mistakes
  Reply With Quote
Old 4th December 2009, 11:31 AM   #9
luka is offline luka  Slovenia
diyAudio Member
 
luka's Avatar
 
Join Date: Sep 2005
Location: in Slovenia :)
Send a message via Skype™ to luka
omg, A and T Labs.... that says it all

mistakes are often expensive, I try to stay away from them as much as I can, even if that means checking everything 10 times
  Reply With Quote
Old 5th December 2009, 01:02 AM   #10
Matt BH is offline Matt BH  United Kingdom
diyAudio Member
 
Join Date: Jul 2009
Location: Cheltenham
lets see this a+t abortion then?
  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 Trouble, wont start - need some advice! Full schematic silversweden Solid State 0 1st January 2009 02:27 PM
Repair SMPS - Need help identifying SMD, schematic attached silversweden Solid State 12 27th December 2008 05:39 PM
SG3526 Offline SMPS schematic need please adi109cj Power Supplies 0 9th October 2007 02:31 PM
schematic for a + -30v ,300va smps sagarverma Power Supplies 25 5th January 2006 11:10 AM
SG 3524 SMPS Schematic -_nando-_ Power Supplies 2 19th December 2005 06:04 PM


New To Site? Need Help?

All times are GMT. The time now is 01:09 PM.


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