排序方式: 共有28条查询结果,搜索用时 265 毫秒
1.
杨宇晴 张新军 赵燕平 秦成明 程艳 毛玉周 杨桦 王健华 袁帅 王磊 琚松青 陈根 邓旭 张开 万宝年 李建刚 宋云涛 龚先祖 钱金平 张涛 《等离子体科学和技术》2018,20(4):45102-111
Recent ion cyclotron resonance frequency(ICRF) coupling experiments for optimizing ICRF heating in high power discharge were performed on EAST. The coupling experiments were focus on antenna phasing and gas puffing, which were performed separately on two ports of the ion cyclotron resonance heating(ICRH) system of EAST. The antenna phasing was performed on the I-port antenna, which consists of four toroidally spaced radiating straps operating in multiple phasing cases; the coupling performance was better under low wave number ∣k_‖∣(ranging from 4.5 to 6.5). By fuelling the plasma from gas injectors, placed as uniformly spaced array from top to bottom at each side limiter of the B-port antenna, which works in dipole phasing, the coupling resistance of the B-port antenna increased obviously.Furthermore, the coupling resistance of the I-port antenna was insensitive to a smaller rate of gas puffing but when the gas injection rate was more than a certain value(1021 s~(-1)), a sharp increase in the coupling resistance of the I-port antenna occurred, which was mainly caused by the toroidal asymmetric boundary density arising from gas puffing. A more specific analysis is given in the paper. 相似文献
2.
3.
4.
1.5MW Ion Cyclotron Wave Heating system was developed, the transmitter and the antenna both have their ground loops, which will severely perturb the system‘s normal operation. To avoid perturbation, a DC break was designed. The S parameter and the VSWR (voltage standing wave ratio) of incident port were calculated; the thermal effect caused by conductor loss and dielectric loss was analyzed. 相似文献
5.
An Ion Cyclotron Range of Frequency (ICRF) system with a radio frequency (RF) power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak (EAST).High RF power transmitters were designed as a part of the research and development (R&D) for an ICRF system with long pulse operation at megawatt levels in a frequency range of 25 MHz to 70 MHz.Studies presented in this paper cover the following parts of the high power transmitter:the three staged high power amplifier,which is composed of a 5kW wideband solid state amplifier,a 100kW tetrode drive stage amplifier and a 1.5MW tetrode final stage amplifier,and the DC high voltage power supply (HVPS).Based on engineering design and static examinations,the RF transmitters were tested using a matched dummy load where an RF output power of 1.5MW was achieved.The transmitters provide 6MW RF power in primary phase and will reach a level up to 12MW after a later upgrade.The transmitters performed successfully in stable operations in EAST and HT-7 devices.Up to 1.8MW of RF power was injected into plasmas in EAST ICRF heating experiments during the 2010 autumn campaign and plasma performance was greatly improved. 相似文献
6.
7.
An antenna array suitable for plasma heating and current drive has been designed for the ion cyclotron resonance frequency range (ICRF) heating on the EAST superconducting tokamak. The ICRF heating is planned to operate in a frequency range of 30 MHz to 80 MHz and hence the antenna geometry is optimized for 55 MHz. The design is based on the conventional strap antenna element. The coupling properties of the antenna are calculated with a slab model of the plasma for the antenna simulation. The coupling code is extended for the analysis of the toroidal antenna array separated by septa. 相似文献
8.
Design of a New Type of Stub Tuner in ICRF Experiment 总被引:2,自引:0,他引:2
In the Ion Cyclotron Range of Frequency(ICRF) heating experiment,impedance matching is of great practical significance,because wide variations in antenna loading are observed within the discharge,in tokamaks operating in H-mode.A sudden decrease in antenna loading accompanying the L-mode to H-mode transition typically occurs on a timescale of a few millisec onds,as does the increase in loading at the H- to L-mode transition.Therefore,it is necessary to match dynamically in the transmission line between the generator output and the antenna input connections[1].A new type of stub tuner being developed utilizes the difference in radio-frequency wavelengths between gas and liquid due to different relative dielectric constants.The impedance matching can be adjusted in realtime in an attempt to track the variations in the antenna loading.Since there are no mechanically moving parts in the short ends of stub,the change can be more convenient and safe,moreover,it can withstand higher voltage without breakdown.this system device will be applied in the HT-7 superconductor Tokamak ICRF experiment. 相似文献
9.
在EAST装置内离子回旋共振加热(ICRF)系统中,天线与液态调配器之间传输线上的驻波电压幅值会因为负载阻抗的变化而变得很大,为此设计了ICRF功率传输预匹配支节。本设计采用解析法和Smith圆图法相结合的分析方式,在ICRF系统中安装了预匹配支节,并对其降压效果进行了测试。测试结果表明,安装预匹配支节之后,预匹配支节与液态调配器之间传输线上的驻波电压幅值得到有效降低,可作为优化ICRF功率传输系统功率传输性能的候选者。 相似文献
10.
Gen CHEN 《等离子体科学和技术》2022,24(1):15602
The Ion Cyclotron Radio Frequency (ICRF) heating antenna on EAST adopts a decoupling device to constrain power coupling among the radiation straps, which was discovered shortcomings such as long size, poor contact, and etc. In order to improve these weak points, a new type decoupler with terminal-loaded tunable capacitor is designed to replace the previous design. Besides the capability of the tunable admittance parameters of decoupler, the withstand voltage of the capacitor is the most significant consideration for working under high power. Therefore, the theoretical analysis carefully elaborates the capacitor withstand voltage, and the detailed analytical equations and criteria for design are given. After the comparative analysis of theoretical calculation and 3D simulation results, the decoupler design scheme is finalized. The capacitor-loaded decoupler has been successfully adopted for ICRF antenna at port N on EAST, and achieved the optimization of adjacent port isolation from −22 to −58 dB at 37 MHz without plasma to restrict mutual coupling. The new design of the decoupler has greatly improved its compactness and automatic adjustment performance, and could be good solution for the decoupling network of ICRF antennas. 相似文献