Solid State Tesla Coil

July 2018

A Tesla coil I made for fun. A first version uses a slayer exiter, while a later improved version uses a full bridge inverter.

Slayer exiter

A first version uses a slayer exiter circuit. This circuit times automatically to the secondary frequency by using an antenna. Because it only uses a half bridge the driving primary can only be shorted to ground, causing low efficiency and heats up the driving FET quite a bit. The secondary cannot create very high voltage but arcs are visible.

Fulll bridge driver

To improve the efficiency and create larger arcs the primary needs to receiver a higher current and therefore a higher voltage. By switching to a full bridge inverter the voltage across the primary can be doubled compared to slayer exiter. The disadvantage is that the circuit is no longer self-tuning. An antenna feeds into a microcontroller setting the switching frequency. By interrupting the switching behavior at certain times an audible sound can be created by the arcs. The FET is switched for IGBTs, so a higher voltage is possible. The circuit was tested and programmed, but the arcs were never very impressive.