• H. Hitomi, H. Hara, K. Kanaoka, K. Sennyu, T. Yanagisawa
  MHI, Kobe

MHI's activities for ILC project will be shown.

• M. Kawamura, Y. Fukui, F. Naito
  KEK, Ibaraki
• E. Chishiro, H. Suzuki, M. Yamazaki
  JAEA, Ibaraki-ken
• K. Hasegawa, S. Shinozaki
  JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken

This report will describe the present status of the power supply systems (PS systems) for the klystrons in the J-PARC (Japan Proton Accelerator Research Complex) linac. The technical specification, the operating experience, and the upgrade plan, of the PS systems will be presented in this report. Now the energy of the J-PARC linac is 181MeV, and the linac includes twenty 324MHz klystrons. In 2012, the energy will be upgraded to 400MeV, and the linac will include twenty 324MHz klystrons and twenty-five 972MHz klystrons. The klystrons are the modulating-anode types. The PS systems include the High voltage DC power supplies (DCPSs) and the anode-modulators. One DCPS drives one or four klystrons, and one anode-modulator drives one klystron.

• M.A. Kemp, A.L. Benwell, C. Burkhart, R.S. Larsen, D.J. MacNair, M.N. Nguyen, J.J. Olsen
  SLAC, Menlo Park, California

The SLAC National Accelerator Laboratory is leading an effort to design a prototype Marx modulator to meet the ILC klystron modulator specifications; a 120 kV (± 0.5%), 140A, 1.6 ms pulse at a 5 Hz prf. A first generation prototype, the P1 Marx, has been developed and is undergoing life testing*. The design of a second-generation Marx, P2, has been completed and most sub-systems have been tested**. The P2 advances the Marx topology demonstrated by the P1; eliminating single-point failures, incorporating advanced diagnostics/prognostics, and optimizing engineering margins to improve system availability. The P2 consists of 32 cells, which are individually regulated at an output of up to 4kV. This is in contrast to the P1 Marx which is collectively regulated by a series "Vernier" Marx. The 30 of 32 cell redundancy allows for up to two cell failures without degrading the modulator output. Failed cells can be quickly replaced and remotely-serviced. This paper presents the design of the P2 Marx. Specific topics discussed include the control architecture, mechanical layout, and power electronics design. Experimental results of both a single and array of cells are presented.

* C. Burkhart, et al., "ILC Marx modulator development status," LINAC, 2008.
** K. Macken, et al., "Towards a PEBB-Based Design Approach for a Marx-Topology ILC Klystron Modulator," PAC, 2009.