AbstractThe ion cyclotron range of frequency (ICRF) heating system at the tokamak ASDEX Upgrade has been in operation since 1991. It still continues to be modified in order to improve its efficiency, flexibility and reliability and to meet changing physics demands. Recently the radio frequency (RF) transmission line feeding system of the antennas has been altered to allow for plasma heating at different frequencies and for current drive at one fixed frequency to be chosen before the shot. A matching system using transmission lines with premagnetized ferrites has been successfully tested. It is planned to use such a system in a feedback loop to allow matching even of fast changes of antenna loading during plasma operation.
The JT-60 radio-frequency heating system: description and R&D results