The construction of the future energy structure of China under the 2050 carbon-neutral vision requires compact direct current(DC)gas-insulation equipment as important nodes and solutions to support electric power tran...The construction of the future energy structure of China under the 2050 carbon-neutral vision requires compact direct current(DC)gas-insulation equipment as important nodes and solutions to support electric power transmission and distribution of long-distance and large-capacity.This paper reviews China's 10-year progress in DC gas-insulated equipment.Important progresses in basic research and industry perspective are presented,with related scientific issues and technical bottlenecks being discussed.The progress in DC gas-insulated equipment worldwide(Europe,Japan,America)is also reported briefly.展开更多
The fusion splicing of double-clad (DC) specialty fibers based on active alignment is crucial to the investigation of high-power monolithic fiber lasers. Given the wave-guiding characteristic of DC fiber, a light st...The fusion splicing of double-clad (DC) specialty fibers based on active alignment is crucial to the investigation of high-power monolithic fiber lasers. Given the wave-guiding characteristic of DC fiber, a light stripper is introduced in an active alignment experiment. We propose a novel method for stripping light that is convenient, highly effcient, and low cost. This method is also effective for low-numerical-aperture beams that escape from the fiber core. A splice loss as low as 0.05 dB is achieved.展开更多
A back-illuminated mesa-structure InGaAs/InP charge-compensated uni-traveling-carrier (UTC) photodi- ode (PD) is fabricated, and its saturation characteristics are investigated. The responsivity of the 40-μm- dia...A back-illuminated mesa-structure InGaAs/InP charge-compensated uni-traveling-carrier (UTC) photodi- ode (PD) is fabricated, and its saturation characteristics are investigated. The responsivity of the 40-μm- diameter PD is as high as 0.83 A/W, and the direct current (DC) saturation current is up to 275 mA. The 1-dB compression point at the 3-dB cutoff frequency of 9 GHz is measured to be 100 mA, corresponding to an output radio frequency (RF) power of up to 20.1 dBm. According to the calculated electric field distributions in the depleted region under both DC and alternating current (AC) conditions, the saturation of the UTC-PD is cansed hv cnmnlete field screening at high optical iniectinn levels展开更多
基金supported by the State Key Laboratory of Power System and Generation Equipment,Dept.of Electrical Engineering,Tsinghua University(Grant No.SKLD22M03)Taikai Innovation Funding(Grant No.JTCB202209210002).
文摘The construction of the future energy structure of China under the 2050 carbon-neutral vision requires compact direct current(DC)gas-insulation equipment as important nodes and solutions to support electric power transmission and distribution of long-distance and large-capacity.This paper reviews China's 10-year progress in DC gas-insulated equipment.Important progresses in basic research and industry perspective are presented,with related scientific issues and technical bottlenecks being discussed.The progress in DC gas-insulated equipment worldwide(Europe,Japan,America)is also reported briefly.
文摘The fusion splicing of double-clad (DC) specialty fibers based on active alignment is crucial to the investigation of high-power monolithic fiber lasers. Given the wave-guiding characteristic of DC fiber, a light stripper is introduced in an active alignment experiment. We propose a novel method for stripping light that is convenient, highly effcient, and low cost. This method is also effective for low-numerical-aperture beams that escape from the fiber core. A splice loss as low as 0.05 dB is achieved.
基金supported by the National Basic Research Program of China(Nos.2011CB301902 and 2011CB301903)the High Technology Research and Development Program of China(Nos.2007AA05Z429 and 2008AA03A194)+2 种基金the National Natural Science Foundation of China(Nos.60723002,50706022,60977022,and 51002085)the Beijing Natural Science Foundation(No. 4091001)the Industry,Academia and Research Combining and Public Science and Technology Special Program of Shenzhen(No.08CXY-14)
文摘A back-illuminated mesa-structure InGaAs/InP charge-compensated uni-traveling-carrier (UTC) photodi- ode (PD) is fabricated, and its saturation characteristics are investigated. The responsivity of the 40-μm- diameter PD is as high as 0.83 A/W, and the direct current (DC) saturation current is up to 275 mA. The 1-dB compression point at the 3-dB cutoff frequency of 9 GHz is measured to be 100 mA, corresponding to an output radio frequency (RF) power of up to 20.1 dBm. According to the calculated electric field distributions in the depleted region under both DC and alternating current (AC) conditions, the saturation of the UTC-PD is cansed hv cnmnlete field screening at high optical iniectinn levels