CONFERENCES AND SYMPOSIA RADIOFREQUENCY LAUNCHERS FOR PLASMA HEATING AND CURRENT DRIVE

摘要

R. Prater, G. Tonon and H. Kimura, respectively, summarized the three sessions on the electron cyclotron, lower hybrid and ion cyclotron ranges of frequencies in the last session. R. Prater discussed the launching system in connection with the applications of ECH. The electron cyclotron system is less demanding in terms of the launcher inside the machine, compared with other RF launchers, but relies on the successful development of high power gyrotrons. He concluded that a multi-MW EC system is necessary to demonstrate the capability for a high power system at competitive cost and efficiency. G. Tonon discussed the LH launching systems of all contributions from the various antenna aspects, antenna structure, conditioning, power handling, coupling, heat load, long pulse operation, new concept and future plans. LHCD has shown important physics results for current drive, profile control, rampup assist and electron heating. He concluded that the progress of launcher technology is one key for these successful results and the LHCD is one major candidate for the current drive of steady state tokamak reactors. Further development of the LH launcher, especially in new concept antennas, and high heat load resisting structures and materials are required to make it more feasible in steady state reactor environments. H. Kimura summarized the status of antenna development for ICRF heating and FWCD. The remarkable progress on ICRF heating is due to the development of high power antennas and impedance matching techniques as well as an understanding of the physics of the antenna-plasma interaction. Antenna designs around the world are tending to converge in many aspects. Recent successful results on FWCD are also due to progress in the antenna technology for current drive. However, much more effort must be devoted to establish FWCD and the reliability of antennas in long pulse operation.