DRSSTC 1 was my first attempt at a DRSSTC type Tesla coil. It wasn’t a super high performer, but it was still able to generate 4 foot sparks with 500 amps of current. The coil’s high frequency inverter was designed using the IXYS 60N60 IGBT’s at the core, taking advantage of their pulsed-current capabilities. The IGBT’s were selected for this design because they operate with lower loses compared to MOSFET’s in pulse- current applications.  IGBT’s operate like a diode with a fixed voltage drop, whereas MOSFET’s have an on-resistance. As a result, losses in IGBT’s go up linearly with current and MOSFET losses increase exponentially.

Secondary	4.5" x 18" winding of 32 AWG wire on ABS form
Tank Capacitor	0.2uF at 14KvDC made up of 0.47uF 2kv caps
Switch Type	Full Bridge of IXGN60N60C2D1
Topload	4.5" x 18" Spun aluminum toroid
Max Spark Length	4 feet
Input Power	120VAC 10A variac 1200VA
Primary	10 turns 1/4" copper tube flat primary tapped at 8.5 turns
Max bus voltage	380VDC

MMC
Because this is a resonant transformer, a high voltage capacitor had to be designed for use in the primary LC circuit. Rather than purchasing a commercially available pulse capacitor, I constructed the tank capacitor from many smaller capacitors. I connected the capacitors in series to achieve the correct voltage rating and paralleled strings to get the correct capacitance. The result is a capacitor known as a MMC or Multi Mini Capacitor. This type of capacitor is substantially more economical than a commercial pulse capacitor of the same value.