Digital Phase Control using IGBTs

[rixor]

My goal is to implement digitally-controlled reverse-phase-control (dimming) of 120V/60Hz AC power, using IGBTs as the switching device and a micro-controller to control them. The reason I am using IGBTs instead of TRIACs is because TRIACs cannot realize reverse-phase-control. IGBTs can, and can be turned off slowly, reducing current spikes and thus reducing EMI - which is a requirement for my application.

Anyways I will probably use this thread to pose a number of questions as I continue to develop my device.

Short disclaimer: this forum will not let me include URLs into this post until I have posted more, so please bare with me for the time being: I can only include part numbers, without links to their respective data-sheets.

So, to start off: While phase control is my ultimate goal, for now I would like to be able to just switch the AC on and off. I have the AC side of the switching circuit already worked out, I just need some help with the gate drive circuitry.

The IGBTs that I have in my possession are the irg4rc10u

To provide the typical +/- 15 volts to drive the gates, I have opto-coupled DC/DC converters. The ones I have are the VASD1-S5-D15-SIP series.

Though the DC/DC devices are opto-coupled, would I still need an opto-coupled IGBT driver such as the HCPL-J312, or can I drive the IGBTs directly from the DC/DC converters?

 

[anorlunda]

ping @Baluncore

 

[Baluncore]

I have the AC side of the switching circuit already worked out, I just need some help with the gate drive circuitry.

The gate drive circuit is dependent on emitter voltages. How many IGBTs are in your AC switching circuit? Can you post your AC switch schematic. Drag and drop it onto your next post.

Datasheet links are here.
IRG4RC10U http://www.irf.com/product-info/datasheets/data/irg4rc10u.pdf

VASD1-S5-D15-SIP https://au.mouser.com/datasheet/2/670/vasd1-sip-1313227.pdf
This DC-DC converter is probably isolated with a high-frequency transformer.

 

[rixor]

Wow, thanks for the reply. That was 11 years ago and I ended up abandoning that project. I still have a bunch of the components and half-made circuit boards lying around, funnily enough, but I haven't really touched any electrical engineering type stuff in a long time. I ended up becoming a software developer and spend most of my technical hours doing that sort of stuff. Anyways, cheers!