Rf-assisted current startup in FED
Auxiliary rf heating of electrons before and during the current rise phase in FED is examined as a means of reducing both the initiation loop voltage and resistive flux expenditure during startup. Prior to current initiation, 1 to 2 MW of electron cyclotron resonance heating (ECRH) power at approximately 90 GHz is used to create a small volume of high conductivity plasma near the upper hybrid resonance (UHR) region. This plasma conditioning permits a small radius (a/sub o/ approximately 0.2-0.4 m) current channel to be established with a relatively low initial loop voltage (<25 V). During the subsequent plasma expansion and current ramp phase, additional rf power is introduced to reduce volt-second consumption due to plasma resistance. The physics models used for analyzing the UHR heating and current rise phases are also discussed.
- Research Organization:
- Oak Ridge Natl Lab, TN, USA
- OSTI ID:
- 6422221
- Report Number(s):
- CONF-811040-; TRN: 83-007767
- Journal Information:
- Proc. Symp. Eng. Probl. Fusion Res.; (United States), Conference: 9. symposium on engineering problems of fusion research, Chicago, IL, USA, 26 Oct 1981
- Country of Publication:
- United States
- Language:
- English
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