Unique power supply system for 2 MW gyrotrons completed in Europe

A unique new power supply system has recently been installed and successfully tested at the European Electron Cyclotron Test Facility in Lausanne (CRPP-EPFL, Switzerland). A project which lasted approximately three years, this fully solid-state power supply system is the first of its kind to feed gyrotrons which generate 2 MW of radio frequency waves for plasma heating and current drive – twice the power of the most performing gyrotrons installed in fusion devices. The 2 MW gyrotron is currently being developed in Europe for the ITER project.

Procured via an EFDA contract, the power supply system fulfills its specifications to 100%. It has been designed and manufactured by Italian company OCEM  in collaboration with the EU Associates, led by the CRPP and EFDA/F4E. The power supply also meets the demanding expected specifications for ITER.

The power supply system is composed of two solid-state power converters, the Main High Voltage Power Supply (MHVPS) and the Body Power Supply (BPS), whose combined operation provides the required voltage and current, up to 100 kV and 80 A. Extensive testing on full power dummy loads before delivery and after installation on-site, proved to be very successful as results show that the system delivers high accuracy on the voltage and excellent dynamic performances combined to high operational flexibility, high availability, low maintenance requirements, high efficiency (>97%) and low impact on the grid (power factor of 0.98 and low harmonic content).

Another advantage is the quick switch-off which limits the total energy discharged in an arc to less than 10J and which therefore protects the gyrotron in a very effective way.