tinyQCW

loneoceans, Tue Nov 24 2015, 08:18PM

Hello all,

I've been working on and off on various projects recently. One of them turned out pretty nice so I thought I'd post something about it.

The motivation of the project was to make a very small QCW coil that could easily fit on top of a table, but still have good performance and be 'plug and play' easy to operate. The size restriction was that it needed to fit into a medium size USPS box (!). The result is a very compact coil, yet capable of sparks just over 32" or so despite its small size! (more than 13x) Power input is from a single IEC input cable from the wall. Because of it's small size I've called it tinyQCW (QCW 2).



The coil uses a full bridge of TO247 IGBTs and has a relatively small 3.5" diameter x 2.4" long winding (so it's a pretty fat ratio), with a small sheet metal toroid. Overall the coil runs pretty cool with the only part getting warm being the secondary coil. Coil has been run up to about 1.25kVA input (no PFC) for a few minutes whereby the secondary gets up to 60+C! I could probably optimize to make it smaller but I'm pretty happy with how it has turned out so far.



Here's a fun video of the coil in action, varying the pulse frequency and power.

Many thanks to all the kind and knowledgeable people who have helped out so much including Steve and Chris - this project would not be possible without their prior work and advice. More to come soon, thanks for reading!