Inverter Technology

[969c1]

Hi guys.
As you can tell, this is my first post and yes, I am new and just learning the welding field. I just received an early Xmas gift from my wife. It is a Miller Dynasty 200DX. It is a beautiful piece! Almost nicer than my wife.
I am also in the process of putting together a presentation for a course in welding that I am taking.
I have to put together a presentation of advancement in GMAW process and how Inverter Technology is the new way.
Is there a link or can someone break it down for me in how inverter technology works, in simple form? I do have a little electrical back ground, from years ago!
Thanks and I appreciate your time.

[84ZMike]

http://en.wikipedia.org/wiki/Welding_power_supply

[journeyman]

invert tech

hope this helps. this took me quite a while to compile[simple brain]

power goes in @ 60 Hz AC, enters machine through an input rectifier assembly [changes AC to DC].

then passes through input capacitors [acts to store power to induce current in the IGBT]

passing through input capacitors power enters IGBT [Insulated Gate Bipolar Transistors] these are what makes the inverter different from trans technology. IGBT is responsible for changing the rectified DC current to high-frequency AC.

then current passes through the primary transformer, stepping down current to make a useable welding current [high voltage/low amperage changes to low voltage/high amps]

then current passes through output rectifiers changing back from AC to DC.

and last but not least current passes through output filters to "clean" current, finally exiting @ 32K Hz DC or an AC current if your configuration allows it.

I know it seems long winded but I also had a great need to understand these machines so when someone asks me what an inverter does I didn't feel like a moron because all I could say was " it's a welder".

hope it helps

[journeyman]

inverter

wikipedia states that an inverter is a "electronic circuit that converts dc to ac"

careful how you interpret this

[shadetreewelder]

http://www.millerwelds.com/education/articles/articles31.html

[Broccoli1]

http://www.millerwelds.com/education/basicelec/

Not a bad read

[Steve]

Inverter technology is not new. It has been around since the days of vacuum tubes. (did I just date myself?). When our power supply died and none were to be found, we got three units that took 115v 60hz and converted that to 3 phase 115v 400hz. Worked till dismantled. Yep I can safely say the electronics of today is packaged a lot smaller than back then.

[fun4now]

969c1
good to have ya with us. lots of great people here with good info to share.

[cadcoke4]

I imagine you already understand a basic electrical transformer... wrap a wire from the input AC voltage, around an iron core. For the output take another wire, and wrap it around the core as well. If the input wire is wrapped around the core 10 times, and the output wire wrapped around 20 times, then the output will be twice the voltage, and half the current. Likewise, you can change the ratio of turns to generate any increase or decrease of voltage(and inversely the current).

An important issues is that the core (an inductors) must be sized according to the frequency used. The lower the frequency, the larger the core must be. The main advantage of switching power supplies is that it reduces the weight of the assembly by reducing the size of the core.

The trick they use is to first change the 60hz input into a much higher frequency, and then the core, which follows, can be much smaller.

Joe Dunfee