An input coupler for the TE021 circular electric mode in a gyroklystron amplifier through using TE811 as a transition coupling mode in a coaxial cavity has been proposed and numerically simulated in a frequency range ...An input coupler for the TE021 circular electric mode in a gyroklystron amplifier through using TE811 as a transition coupling mode in a coaxial cavity has been proposed and numerically simulated in a frequency range of Ka-Band with HFSS code. The coupling efficiency of the TE021 mode and the suppression for the TE811 mode in the main cylindrical cavity are deliberately considered by adjusting the position and size of coupling holes as well as the radius of the drift tubes. The numerical results show that the TE21 mode can successfully be excited, and rational coupling efficiency and high mode purity for the TE021 mode in the cylindrical cavity can be reached for the engineering application of gyroklystron amplifier study.展开更多
An RF power coupler is one of the key components in a superconducting （SC） linac. It provides RF power to the SC cavity and interconnects different temperature layers （1.8 K, 4.2 K, 70 K and 300 K）. The TTF-Ⅲ cou...An RF power coupler is one of the key components in a superconducting （SC） linac. It provides RF power to the SC cavity and interconnects different temperature layers （1.8 K, 4.2 K, 70 K and 300 K）. The TTF-Ⅲ coupler is one of the most promising candidates for the High Energy （HE） linac of Project X, but it cannot meet the average power requirements because of the relatively high temperature rise on the warm inner conductor, so some design modifications will be required. In this paper, we describe our simulation studies on the copper coating thickness on the warm inner conductor with RRR values of 10 and 100. Our purpose is to rebalance the dynamic and static loads, and finally lower the temperature rise along tbe warm inner conductor. In addition, to get stronger coupling, better power handling and less multipacting probability, one new cold part design was proposed using a 60 mm coaxial line; the corresponding multipacting simulation studies have also been investigated.展开更多
It is very important to predict the coupling between the cavity and the high power input source in the coupler design. In this paper, a time domain method is used to calculate the external quality factor Qext for the ...It is very important to predict the coupling between the cavity and the high power input source in the coupler design. In this paper, a time domain method is used to calculate the external quality factor Qext for the BEPC Ⅱ superconducting cavity. A comparison between simulation results and experimental results is presented. The results of simulation and measurement of Qext have a good agreement within an error of 10%. The geometry parameters related with Qext are also studied.展开更多
High power conditioning of the input coupler for BEPCII superconducting cavity has been performed. After room temperature conditioning, the RF power of 150 kW with continuous wave at standing wave mode passed through ...High power conditioning of the input coupler for BEPCII superconducting cavity has been performed. After room temperature conditioning, the RF power of 150 kW with continuous wave at standing wave mode passed through the coupler without any problem. Meanwhile, a series of methods have also been studied to improve the performance of the coupler during the beam operation. Up to now, the input coupler can feed a RF power up to 100 kW stably with high current of 250 mA at 2.5 GeV.展开更多
The BEPCII storage ring adopts two 500 MHz superconducting cavities （SCC）. Each one is equipped with a 500 MHz input power coupler. The coupler is to feed 150 kW power in continuous wave （CW） mode with both standi...The BEPCII storage ring adopts two 500 MHz superconducting cavities （SCC）. Each one is equipped with a 500 MHz input power coupler. The coupler is to feed 150 kW power in continuous wave （CW） mode with both standing and traveling wave modes. Due to high power feeding and high frequency of the coupler, its fabrication is a big challenge. The fabrication started with two key components, the window and the antenna. Up to now, two sets including windows and antennas have been made by IHEP. And a 270 kW RF power in CW has passed through the coupler during the high power test. The fabrication details are presented in this paper.展开更多
文摘An input coupler for the TE021 circular electric mode in a gyroklystron amplifier through using TE811 as a transition coupling mode in a coaxial cavity has been proposed and numerically simulated in a frequency range of Ka-Band with HFSS code. The coupling efficiency of the TE021 mode and the suppression for the TE811 mode in the main cylindrical cavity are deliberately considered by adjusting the position and size of coupling holes as well as the radius of the drift tubes. The numerical results show that the TE21 mode can successfully be excited, and rational coupling efficiency and high mode purity for the TE021 mode in the cylindrical cavity can be reached for the engineering application of gyroklystron amplifier study.
文摘An RF power coupler is one of the key components in a superconducting （SC） linac. It provides RF power to the SC cavity and interconnects different temperature layers （1.8 K, 4.2 K, 70 K and 300 K）. The TTF-Ⅲ coupler is one of the most promising candidates for the High Energy （HE） linac of Project X, but it cannot meet the average power requirements because of the relatively high temperature rise on the warm inner conductor, so some design modifications will be required. In this paper, we describe our simulation studies on the copper coating thickness on the warm inner conductor with RRR values of 10 and 100. Our purpose is to rebalance the dynamic and static loads, and finally lower the temperature rise along tbe warm inner conductor. In addition, to get stronger coupling, better power handling and less multipacting probability, one new cold part design was proposed using a 60 mm coaxial line; the corresponding multipacting simulation studies have also been investigated.
基金Supported by National Natural Science Foundation of China(k711360503)
文摘It is very important to predict the coupling between the cavity and the high power input source in the coupler design. In this paper, a time domain method is used to calculate the external quality factor Qext for the BEPC Ⅱ superconducting cavity. A comparison between simulation results and experimental results is presented. The results of simulation and measurement of Qext have a good agreement within an error of 10%. The geometry parameters related with Qext are also studied.
基金National Natural Science Foundation of China (k711360503)
文摘High power conditioning of the input coupler for BEPCII superconducting cavity has been performed. After room temperature conditioning, the RF power of 150 kW with continuous wave at standing wave mode passed through the coupler without any problem. Meanwhile, a series of methods have also been studied to improve the performance of the coupler during the beam operation. Up to now, the input coupler can feed a RF power up to 100 kW stably with high current of 250 mA at 2.5 GeV.
基金Supported by National Natural Science Foundation of China (k711360503)
文摘The BEPCII storage ring adopts two 500 MHz superconducting cavities （SCC）. Each one is equipped with a 500 MHz input power coupler. The coupler is to feed 150 kW power in continuous wave （CW） mode with both standing and traveling wave modes. Due to high power feeding and high frequency of the coupler, its fabrication is a big challenge. The fabrication started with two key components, the window and the antenna. Up to now, two sets including windows and antennas have been made by IHEP. And a 270 kW RF power in CW has passed through the coupler during the high power test. The fabrication details are presented in this paper.
