Abstract
A new design concept aims to improve the voltage stand-off by using two repositioned 9-inch Al2O3 windows, to avoid/reduce the neutron impact on the ceramic by moving the window far from antenna, and to reduce the nearby E-fields by optimizing the shape of the conducting structures. New RF windows position is found to be close to the voltage node and determined from the standing wave patterns at the most used frequency of 36.5 MHz. The return loss coefficient S11 is between -30 and -55 dB for the whole operating frequency range. The calculated power losses for the new RF window structures are less than 0.13 kW each at 1 MW of incident power. Modelling shows maximum E-field less than 1.9 kV/mm in a torus and private vacuum of the feedthrough. The dimensions, E-fields and transmission make this design relevant to a possible DEMO ICRF system.
| Original language | English |
|---|---|
| Article number | 113646 |
| Journal | Fusion Engineering and Design |
| Volume | 193 |
| DOIs | |
| State | Published - Aug 2023 |
| Externally published | Yes |
Funding
This work has been carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (Grant Agreement No 101052200 — EUROfusion). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them. The views and opinions expressed herein do not necessarily reflect those of the ITER Organization. The authors want to acknowledge and specially thank Mr. Gerhard Siegl for his generous support and fruitful discussions.
Keywords
- ICRF heating
- RF window
- Transmission line
- Vacuum feedthrough
- Voltage standoff
