• M.-C. Lin, L.-H. Chang, M.H. Chang, L.J. Chen, W.-S. Chiou, F.-T. Chung, F. Z. Hsiao, Y.-H. Lin, C.H. Lo, H.H. Tsai, M.H. Tsai, Ch. Wang, T.-T. Yang, M.-S. Yeh, T.-C. Yu
  NSRRC, Hsinchu
• M. Di Palma, S. Lange, H. Lehmann, K. Schippl
  NEXANS Deutschland Industries AG & Co. KG, Moenchengladbach

The National Synchrotron Radiation Research Center is constructing the Taiwan Photon Source (TPS), a 3-GeV synchroton facility. The superconducting radio frequency (SRF) cavity modules are selected as the accelerating cavities in the electron storage ring. A test area for the SRF modules is established in the RF laboratory, which includes cryogenic environment, RF transmitter, low level RF control system, and radiation shielded space. The liquid helium is transferred from the cryogenic plant in the experimental area of the Taiwan Light Source (TLS), which is not only far from the RF laboratory but also characterized by a complicated route of 205 meters. The main concerns on the cryogenic transfer are the installation difficulty, heat loss, two-phase flow, and pressure loss. Instead of a multi-channel transfer line, which would request a long installation period on radiation-restrict area, flexible cryogenic transfer lines from Nexans were chosen. The installation period was dramatically reduced to one week. With a test Dewar in the RF lab and valve boxes on both ends of the transfer lines, a long distance cryogenic transfer system was completed and proved to work functional.

• H.H. Tsai, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, H.C. Li, M.-C. Lin, T.F. Lin, C.P. Liu
  NSRRC, Hsinchu

The TPS is 3 GeV photon source under construction in Taiwan. The electron needs four superconducting RF cavities to maintain the energy. The construction of a new refrigeration/liquefaction helium plant is under way to supply the liquid helium for superconducting RF cavities. This is the third year of the seven years project and part of the design features and parameters is different from the prilimilary design. This paper presents the design of the cryogenic system, which is including the features of the new cryogenic plant, the pressure drop of warm helium pipeline, the distribution valve box and the multichannel line. The design of liquid nitrogen supply line and the phase separator will be also included.

• T.-C. Yu, L.-H. Chang, M.-C. Lin, Ch. Wang, M.-S. Yeh
  NSRRC, Hsinchu

The RF power source using solid-state amplifier for accelerator application has become popular in recent years. The amplifiers array using power divider and power combiner could obtain equivalent power level as those using klystron or IOT. Such solid-state RF power source also has the advantage of easy maintenance, low cost, low DC power voltage and high flexibility. The development of solid-state power amplifier module at 499.65 MHz using the latest RF power chip has been built to have the power level of 900 Watts with above 60% efficiency of single power module. The more power that one module can provide, the less number of modules would be required under the same total output power of amplifiers array. Thus, the construction of a transmitter by solid-state technique for RF system would be less complex for easy maintenance.