Simon Liu Wants to Put a "Tokamak" on Every Desk, with This Open Source Plasma Toroid Generator

Electrical engineering student Simon Liu has penned a guide to creating your own plasma toroid generator in the comfort of your home or office — or, as he puts it, building a "tokamak" in your home.

"We have built a beautiful purple plasma toroid," Liu explains of the project, created in partnership with pseudonymous maker "Skylake," "and everything about it is open source. All the parts can be purchased cheaply, and we believe this is the lowest-cost way to build your own plasma toroid in the world."

While Liu refers to the device as a "tokamak," a magnetic field confinement system originally developed for sustaining and controlling nuclear reactions in power stations, this particular device has no actual magnetic confinement for the job of turning plasma into an attractive ring — which is safely kept away from prying fingers inside an 80mm glass jar filled with xenon gas.

A clever PCB top-plate provides a bracket for the winding of a four-turn copper coil, which sits above a control board with a hefty aluminum heatsink — responsible for keeping a high-power MOSFET from melting, with the aid of a fan for forced-convection cooling. The glass globe sits on top, nestled in the coil — and, when actuated with a piezoelectric igniter, plays host to the eerie floating plasma ring.

"Stay away from the coil when the circuit is working, as the high temperature of the coil may cause burns," Liu advises of those looking to build their own. "The circuit will heat up. It is not recommended to run the circuit for a long time. It is recommended to work continuously for no more than two minutes."

A full build guide is available in Liu's Instructables page, while the PCB manufacturing files are available on GitHub under the reciprocal Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International license.

Correction (09/26/2024): This article has been updated to clarify that the plasma generator, while inspired by tokamak technology, does not use magnetic confinement to shape the plasma.