Design of an Oil-Immersed Pulse Modulator for X -Band 50-MW Klystron

• Published in: IEEE transactions on plasma science Vol. 51; no. 3; pp. 1 - 6
• Main Authors: Liu, Yong-Fang, Matsumoto, Hiroshi, Gu, Ming, Li, Guo-Qiang, Li, Sheying
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Capacitors; Circuit design; Circuit protection; Design; Design criteria; Electronic components; Flat-top stability; Inductance; Klystrons; Modulation; oil-immersed pulse modulator; Pulse duration; pulse transformer; Pulse transformers; pulse-forming network (PFN); Rectifiers; Systems stability; thyratron; Thyratrons
• ISSN: 0093-3813; 1939-9375
• DOI: 10.1109/TPS.2023.3248094

This article presents a compact high-voltage pulse modulator used for a 50-MW <inline-formula> <tex-math notation="LaTeX">X</tex-math> </inline-formula>-band pulsed klystron (11.4 GHz) at Shanghai Advanced Research Institute, Chinese Academy of Sciences (SARI, CAS). The pulse modulator includes a ten-section pulse-forming network (PFN), protection circuits, a thyratron module, and a pulse transformer. To reduce the volume of the pulse modulator and maintain the system stability, an oil-immersed tank is proposed to insulate the main electronic components, which leads to a volume reduction of 65%. The modulator is designed with a peak pulse voltage of 427 kV, a peak pulse current of 304 A, a repetition rate of 50 Hz, and a flat-top pulsewidth of 1.3 <inline-formula> <tex-math notation="LaTeX">\mu </tex-math> </inline-formula>s. The circuit schematic is provided, while the design criteria of the main components and mechanical structure are discussed. The experimental results and measurements show the design and hardware to be capable of fulfilling the requirements.