UK research organisation developing an Ohmic Heating (OH) Network is looking to develop its technology in to new sectors via a licencing agreement. Essentially the Ohmic heating (aka resistive heating, or Joule heating) is used to induce and maintain the plasma current in the JET tokamak; raising the temperature of the plasma to around 20,000,000 °C. The OH network constructed at CCFE consists of high current opening and closing switches, a counter-pulse circuit, commutating resistors, and various safety and protection devices and their controls.
The switching network can withstand currents of up to 40 kA and has an (80bar) air blast system to eliminate the arc when the switch is opened. A counter-pulse circuit is installed in case of arc re-strike, which charges a bank of high storage capacitors (1.2 mF at 25 kV).
The OHC is currently used to induce and maintain the plasma current in the JET nuclear fusion tokamak however the apparatus could potentially be developed for use in three broader applications in various sectors. These are the testing of industrial circuit components (e.g switches and busbars), the high current or high voltage OH application onsite or high-speed data acquisition for analysis.