max
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« on: May 22, 2021, 06:52:27 06:52 » |
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Hi,
I need a reliable circuit to drive the high power SCRs (300A) gates connected back to back to control AC phase angle, the line voltage is 380V. The scr requires min 3V and 200mA gate drive.
Regards
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« Last Edit: May 22, 2021, 11:23:51 11:23 by max »
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Old_but_Alive
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« Reply #1 on: May 22, 2021, 08:26:21 08:26 » |
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I fought Ohm's Law ... and the law won I only use Mosfets because I have a Bipolar mental disorder :-)
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digitalmg
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« Reply #2 on: May 22, 2021, 05:49:13 17:49 » |
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This is the control part of the thyristor, in a project I made for an SCR up to 500A at 400V, you should preferably add an RC snubber circuit between anode and cathode, C - 0,1uF/2000v, R - 47ohm/3W to not exceed dV / dT. For back to back use a double SCR Trigger Transformer for example KMB229-311.
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« Last Edit: May 22, 2021, 05:55:28 17:55 by digitalmg »
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max
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« Reply #3 on: May 23, 2021, 06:35:36 06:35 » |
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Hi digitalmg,
Thanks for sharing the circuit, where I can find the KMB229-311 pulse transformer?
Regards
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digitalmg
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« Reply #5 on: May 23, 2021, 10:19:41 10:19 » |
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I buy from Aliexpress, www.aliexpress.com/item/1005001580358692.htmlbut you can use any SCR Trigger Transformer with Frequency range: 1KHz ~ 10KHz Regards
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mbyka
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« Reply #6 on: May 23, 2021, 08:04:47 20:04 » |
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max
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« Reply #7 on: May 27, 2021, 12:36:34 12:36 » |
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Hi digitalmg,
Please advise what changes are required in the circuit for 800A scr, gate input 4.5v 250mA
The KMB229-311 pulse transformer datasheet says it is suitable for scr with < 500A current.
Regards
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digitalmg
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« Reply #8 on: May 27, 2021, 12:52:15 12:52 » |
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Hi,
Replace the transformer with one designed for 1000A, for example KMB419-311S.
Regards
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