Using high power IGBT bricks to
push hundreds of amps of current through a metal workpiece via electrical induction from a resonant LC circuit to cause contactless heating by IIR losses. My AP physics C E&M midyear project!
This device was built for a regional science team event using an opamp oscillator circuit with amplitude proportional to the conductivity (which in turn is proportional to the salinity) of a sample of water. The output is rectified and filtered, diode drop hidden by another opamp, to produce a DC voltage that is analyzed by an ICL7107 sample&hold/ADC/Binary to 7 Segment chip.
The design is a derivative of this person’s work.
Built in only 2 days with junk found around MITERS and my DRSSTC’s primary/secondary, this coil produces up to 2 – 3 foot streamers and ground arcs!
With a few improvements like a rotary gap instead of an unquenched static gap and a slightly larger secondary, this coil could probably push another 1 – 2 feet of spark length.