SUCCESS! TIG DC --> Advanced SquareWave INVERTER is working (prototype)

[Winfield Hill]

Ignoramus22022 wrote...

1. No interlock (bridged certain pair of contacts). I could use
turn-on and turn-off resistors for every gate. The more resistance,
the slower is the turn on or turn off. Turn on and turn off start
occurring simultaneously.

Don't forget diodes in series with gate resistors to separately
control on and off delays. Like this popular scheme for rapid
turnoff, to get "break before make."

.. ---+----/\/\-----+--- gate
.. | |
.. '--|<|--/\/\--'

 

[Ignoramus22022]

Ignoramus22022 wrote...

Don't forget diodes in series with gate resistors to separately
control on and off delays. Like this popular scheme for rapid
turnoff, to get "break before make."

. ---+----/\/\-----+--- gate
. | |
. '--|<|--/\/\--'

Semikron 23 has separate pins for the off wire and the on wire. One is
used for sourcing, another for sinking. Very handy.

The on bias voltage is 15V, the off bias voltage is -8v.

http://igor.chudov.com/projects/Homemade-TIG-DC-to-AC-Inverter/Schematic/SKHI_23_12.pdf

Like I said, I found out that the shorting time is too much and that
the bridge conducts too much even with no load. I will have to adjust
gate resistors, that means one more hour spent.

i
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