分类: 核科学技术 >> 核科学与技术 提交时间: 2024-04-24
摘要: 射频功率源是负离子源中性束注入电源系统的重要组成部分,它为射频离子源产生等离子体和维持稳定放电提供射频电流。根据设计指标提出了全固态功率放大器设计结构,并对射频通路环节的缓冲放大电路、预推动放大器、功率放大器、功率合成器、输出匹配和滤波进行了设计与分析。最后过实验实现了150kW的射频等离子体放电,验证了这一拓扑结构的可行性。
分类: 物理学 >> 核物理学 提交时间: 2024-03-27
摘要: 采用有限元法和热介电张量模拟研究了非一次吸收假设,以及一次吸收假设对EAST四电流带天线少数离子加热波传播和功率沉积的影响。模拟结果显示:在其他参数相同的条件下,当天线电流相位为(0 0 π π)和(0 π π 0)时,两种模型计算的天线附近电场分布基本一致;当天线电流相位为(0 π 0 π)时,两个模型的电场模拟结果出现显著差别。环向传播多圈的离子回旋波是导致结果差异的主要原因。环形聚变装置中,当波的平行波数较大时,一次吸收假设的模拟结果偏小。对于环形聚变装置,一次吸收假设的适用性需要进一步系统的研究。
分类: 物理学 >> 电磁学、光学、声学、传热、经典力学和流体动力学 分类: 物理学 >> 气体、等离子体、放电物理 提交时间: 2017-11-27
摘要: An important feature of China Fusion Engineering Test Reactor(CFETR) project is represented by the additional heating obtained from the injection of neutral beams based on accelerated negative ions. For the neutral beams based on negative ions, the most important measurements are beam uniformity, beamlet divergence and stripping losses. According to the CFETR requirement, the maximum allowed beam divergence angle and beam non-uniformity are 6 mrad and ±10%,respectively. As 1D carbon tiles have large ratio between perpendicular conductivity and parallel conductivity and high stability, they can be used for beam uniformity and beamlet divergence measurement. This paper presents the investigation of the influence on the response of 1D carbon tile having the thermal characteristics and features of some dedicated diagnostics. Simulations show that it will be possible to verify experimentally whether the beam meets the requirement about the maximum allowed value. This work lays a foundation for design and application of high precision beam diagnostic targets.
分类: 物理学 >> 核物理学 提交时间: 2017-11-27
摘要: Neutral beam injection has been recognized as one of the most effective means for plasma heating.According to the research plan of the EAST physics experiment, two sets of neutral beam injector were built and operational in 2014. The paper presents the development of beam diagnosis system for EAST neutral beam injector (NBI) and the latest experiment results obtained on the test-stand and EAST-NBI-1 and 2. The results show that the optimal divergence angle is (0.62°, 1.57°) and the full energy particle is up to 77%. They indicate that EAST NBI work properly and all targets reach or almost reach the design targets. All these lay a solid foundation for the achievement of high quality plasma heating for EAST.
分类: 物理学 >> 核物理学 分类: 物理学 >> 电磁学、光学、声学、传热、经典力学和流体动力学 提交时间: 2017-03-02
摘要: The gyrotron is the most important device in the ECRH system. The cathode power supply is one of the most important ancillary devices for gyrotron. Some interesting transient phenomena about the cathode voltage and the cathode current was found in the gyrotron operation. In order to explain these phenomena, an equivalent model of the magnetron injection gun was proposed. The equivalent circuit is composed of parallel resistors and capacitors, and it can explain the test results very well.