DESIGN AND TEST RESULTS ON A 45-KV PULSED POWER MODULATOR FOR A 1.5-MW MAGNETRON APPLICATION OF KSTAR LHCD

  • Jang, Sung-Duck (Division of Engineering, Pohang Accelerator Laboratory, Pohang University of Science and Technology) ;
  • Son, Yoon-Gyu (Division of Engineering, Pohang Accelerator Laboratory, Pohang University of Science and Technology) ;
  • Oh, Jong-Seok (Division of Engineering, Pohang Accelerator Laboratory, Pohang University of Science and Technology) ;
  • Bae, Young-Soon (National Fusion Research Center) ;
  • Cho, Moo-Hyun (Division of Engineering, Pohang Accelerator Laboratory, Pohang University of Science and Technology) ;
  • NamKung, Won (Division of Engineering, Pohang Accelerator Laboratory, Pohang University of Science and Technology)
  • Published : 2006.12.01

Abstract

The microwave heating system of KSTAR consists of ECH and LHCD. ECH and LHCD offer the benefits ofa reliable operation at the start of plasma formation and a non-inductive current drive durable steady state operation, respectively. LHCD uses a C-band microwave system with a frequency of 5 GHz. A pulsed power modulator with a power of 3.6 MW, $4{\mu}S$, 200 pps is required to drive the high-powered magnetron. The development of a pulse modulator with 1:4 pulse transformers is the focus of the research in this study. The peak power handling capability is 3.6 MW (45 kV, 90 A at load side with a pulse width of $4{\mu}S$). This paper describes the system overview and test results of the pulsed modulator. In particular, a simulated waveform is compared with the tested waveform.

Keywords

References

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