Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Current source for micro/ micro spot TIG welding machine?

Status
Not open for further replies.

berger.h

Member level 5
Joined
Sep 30, 2016
Messages
93
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Activity points
2,355
I apologize for a possible amateur and unintentional question.
I did now a 40V 30A MCU controllable power source as Synchronous Buck on 250khz drives LM5145 and I was surprised how well this little resource worked.
At the same time, I often try micro TIG welders, which can be very precise, so they use small electrodes typically 0.5-0.8mm and current typically 0,1 - 40A
and pulse welding 0,1-10ms
any as thit video or this machine

I was wondering if one or two paralellally such sources controlled by the processor could not be used as a source of current for a micro-tig welding machine
Maybe it's nonsense, because there are high demands on dI/dt, etc.
nevertheless I would like to know your opinion, it is worth considering or it is nonsense
 

it was meant as two 30A supply working as one 60A PS.
but it is not about the basic question. For micro TIG machines, it is enough for most work to be currents up to 30A
that means one source enough.
I am primarily concerned with whether the LM5140 controlled source is suitable for the load represented by the TIG welding torch
 

Consider interleaving two converters. Each draws 30A avg. Turn them on staggered at equal intervals.

This concept can be expanded to 3 or more converters. However I can't advise what control IC can accomplish this.
 

An arc welder power supply would be expected to work in constant current mode, does your design?

I doubt that the output filters are suited for pulsed operation. You better start with a known working welder power supply circuit.
 

Thanks for the answers.

>I can't advise what control IC can accomplish this.
LM5145 have synchonisation I/O anm is possible synchronise more Power supply.

>I doubt that the output filters are suited for pulsed operation
That is a question :sad:
However 250kHz and high frequency sources have a lower L C at the output than common welder machine, I think.


I have come across another thing
TIG welding machine have HF high voltage ignition.
HF generato on output high frequence high voltage ignition voltage for example 6k V
In welding machine is on output big col working as transformer see picture over lagre 2x8mm coil going welding large DC current and over secundar winding going HF voltage for example 15kV and this volta is the result is on a big coil, large DC welding current and large AC voltage for ingition.

But I do not understand how high the voltage will not damage C and Q before the coil

HF.png
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top