High Power RF Transmitters for ICRF Applications on EAST

• Published in: Plasma science & technology 2013-03, Vol.15 (3), p.261-265
• Main Authors: Mao, Yuzhou, Yuan, Shuai, Zhao, Yanping, Zhang, Xinjun, Chen, Gen, Cheng, Yan, Wang, Lei, Ju, Songqing, Deng, Xu, Qin, Chengming, Yang, Lei, Kumazawa, R.
• Format: Article
• Language: English
• Subjects: Amplifiers; Cyclotron frequency; Devices; EAST; High voltages; ICRF; Ion cyclotron radiation; Radio frequencies; Research and development; RF应用; Tetrodes; Transmitters; 功率发射机; 固态放大器; 射频发射器; 等离子体性能; 高功率
• ISSN: 1009-0630
• DOI: 10.1088/1009-0630/15/3/14

An Ion Cyclotron Range of Frequency （ICRF） system with a radio frequency （RF） power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak （EAST）. High RF power transmitters were designed as a part of the research and development （R~D） for an ICRF system with long pulse operation at megawatt levels in a frequency range of 25 MHz to 70 MHz. Studies presented in this paper cover the following parts of the high power transmitter： the three staged high power amplifier, which is composed of a 5 kW wide- band solid state amplifier, a 100 kW tetrode drive stage amplifier and a 1.5 MW tetrode final stage amplifier, and the DC high voltage power supply （HVPS）. Based on engineering design and static examinations, the RF transmitters were tested using a matched dummy load where an RF output power of 1.5 MW was achieved. The transmitters provide 6 MW RF power in primary phase and will reach a level up to 12 MW after a later upgrade. The transmitters performed successfully in stable operations in EAST and HT-7 devices. Up to 1.8 MW of RF power was injected into plasmas in EAST ICRF heating experiments during the 2010 autumn campaign and plasma performance was greatly improved.