Purpose Flexible waveguides,which allow for greater deformation as compared to traditional hard waveguides,are highly useful for simplifying waveguide system assemblies.However,the peak powers of these waveguides have...Purpose Flexible waveguides,which allow for greater deformation as compared to traditional hard waveguides,are highly useful for simplifying waveguide system assemblies.However,the peak powers of these waveguides have been limited to several megawatts in non-vacuum environments.Herein,a novel flexible waveguide was developed for the S-band(2856 MHz)with the aim of facilitating the interconnection of two hard waveguides.Methods The flexible waveguide was composed of brass,and its surface was plated with oxygen-free high-conductivity copper for brazing with stainless steel flanges in a vacuum furnace.By connecting the stainless steel flanges together,it can be applied to a high-vacuum environment.Results The prototype exhibited good measurement results in low-power microwave tests;the results of a 72-h vacuum leak test showed satisfactory vacuum performance as well,and no obvious surface collapse was observed.High-power microwave commissioning was conducted between June and July 2019;the waveguide showed a maximum average power of approximately 2.7 kW.Conclusion Unfortunately,the prototype was damaged after reaching that power level,which indicates the need for further optimization of the fabrication process.From our experiment,it is clear that the flexible waveguide cannot be used in large accelerators because of its average power limit.展开更多
Purpose A novel high-directivity high-power waveguide directional coupler(DC)working at 2998.8 MHz is developed for the High Energy Photon Source.It can help the phase control system to obtain a very accurate microwav...Purpose A novel high-directivity high-power waveguide directional coupler(DC)working at 2998.8 MHz is developed for the High Energy Photon Source.It can help the phase control system to obtain a very accurate microwave signal,which is very important to minimize the beam emittance.Methods The novel reversely placed T-type coupling piece helps to obtain a high directivity.The N-type high-vacuum feedthroughs for vacuum sealing instead of the traditional ceramic plate is beneficial to holding a higher peak power.The simulation and the high-power commissioning are accomplished in the Institute of High Energy Physics(IHEP),while the fabrication and the low-power test are conducted in cooperation with the manufacturer.Results Both the single-coupler and the dual-coupler DCs are developed with a directivity of more than 35 dB while keeping the coupling factor within 60±0.5 dB.Finally,69.4%of all the fifty-two mass produced DCs have got a directivity of more than 40 dB.Conclusion:The mature manufacturing process for mass production is obtained.The novel high-directivity high-power waveguide DC can be mass produced with an actually internationally leading performance.展开更多
Purpose The High-Energy Photon Source(HEPS)is a 6 GeV storage ring-based light source under construction in Beijing,China.Its accelerator consists of a 6 GeV storage ring,a full-energy booster,an S-band normal-conduct...Purpose The High-Energy Photon Source(HEPS)is a 6 GeV storage ring-based light source under construction in Beijing,China.Its accelerator consists of a 6 GeV storage ring,a full-energy booster,an S-band normal-conducting 500 MeV linac,and three transport lines.As the beginning of HEPS,a stable linac is quite important,which needs a qualified waveguide distribution system to transmit microwave power from klystrons to accelerating structures.Methods Installation and high-power conditioning of the HEPS linac were performed from February to September 2022.The assembly and conditioning of the waveguide distribution system were completed in April and July,respectively.The design of the waveguide distribution system began in 2018 and was finalized at the end of 2020 after multiple iterations.Results Owing to careful design,fabrication,and assembly preparation,the assembly and conditioning of the system proceeded smoothly and considerable time was saved.Conclusion The entire process from the design to the ultimate realization of the system is introduced in detail in this paper.Satisfactory measurement results were obtained for some waveguide components.展开更多
基金Funded by Youth Innovation Promotion Association CAS(2020015).
文摘Purpose Flexible waveguides,which allow for greater deformation as compared to traditional hard waveguides,are highly useful for simplifying waveguide system assemblies.However,the peak powers of these waveguides have been limited to several megawatts in non-vacuum environments.Herein,a novel flexible waveguide was developed for the S-band(2856 MHz)with the aim of facilitating the interconnection of two hard waveguides.Methods The flexible waveguide was composed of brass,and its surface was plated with oxygen-free high-conductivity copper for brazing with stainless steel flanges in a vacuum furnace.By connecting the stainless steel flanges together,it can be applied to a high-vacuum environment.Results The prototype exhibited good measurement results in low-power microwave tests;the results of a 72-h vacuum leak test showed satisfactory vacuum performance as well,and no obvious surface collapse was observed.High-power microwave commissioning was conducted between June and July 2019;the waveguide showed a maximum average power of approximately 2.7 kW.Conclusion Unfortunately,the prototype was damaged after reaching that power level,which indicates the need for further optimization of the fabrication process.From our experiment,it is clear that the flexible waveguide cannot be used in large accelerators because of its average power limit.
基金Funded by Youth Innovation Promotion Association CAS(2020015)
文摘Purpose A novel high-directivity high-power waveguide directional coupler(DC)working at 2998.8 MHz is developed for the High Energy Photon Source.It can help the phase control system to obtain a very accurate microwave signal,which is very important to minimize the beam emittance.Methods The novel reversely placed T-type coupling piece helps to obtain a high directivity.The N-type high-vacuum feedthroughs for vacuum sealing instead of the traditional ceramic plate is beneficial to holding a higher peak power.The simulation and the high-power commissioning are accomplished in the Institute of High Energy Physics(IHEP),while the fabrication and the low-power test are conducted in cooperation with the manufacturer.Results Both the single-coupler and the dual-coupler DCs are developed with a directivity of more than 35 dB while keeping the coupling factor within 60±0.5 dB.Finally,69.4%of all the fifty-two mass produced DCs have got a directivity of more than 40 dB.Conclusion:The mature manufacturing process for mass production is obtained.The novel high-directivity high-power waveguide DC can be mass produced with an actually internationally leading performance.
基金Funded by Youth Innovation Promotion Association CAS(2020015)and the HEPS project.
文摘Purpose The High-Energy Photon Source(HEPS)is a 6 GeV storage ring-based light source under construction in Beijing,China.Its accelerator consists of a 6 GeV storage ring,a full-energy booster,an S-band normal-conducting 500 MeV linac,and three transport lines.As the beginning of HEPS,a stable linac is quite important,which needs a qualified waveguide distribution system to transmit microwave power from klystrons to accelerating structures.Methods Installation and high-power conditioning of the HEPS linac were performed from February to September 2022.The assembly and conditioning of the waveguide distribution system were completed in April and July,respectively.The design of the waveguide distribution system began in 2018 and was finalized at the end of 2020 after multiple iterations.Results Owing to careful design,fabrication,and assembly preparation,the assembly and conditioning of the system proceeded smoothly and considerable time was saved.Conclusion The entire process from the design to the ultimate realization of the system is introduced in detail in this paper.Satisfactory measurement results were obtained for some waveguide components.