大面积负离子束源磁过滤器的设计及实验研究  

Design and experimental research of magnetic filter for large area negative ion beam source

作　　者：谢亚红 谢俊炜 韦江龙 顾玉明 蒋才超 潘军军[1] 许永建 谢远来 胡纯栋 XIE Ya-hong;XIE Jun-wei;WEI Jiang-long;GU Yu-ming;JIANG Cai-chao;PAN Jun-jun;XU Yong-jian;XIE Yuan-lai;HU Chun-dong(Institute of Plasma Physics,HFIPS,Chinese Academy of Science,Hefei 230031;University of Science and Technology of China,Hefei 230026)

机构地区：[1]中国科学院合肥物质科学研究院等离子体物理研究所,合肥230031 [2]中国科学技术大学,合肥230026

出　　处：《核聚变与等离子体物理》2023年第4期407-411,共5页Nuclear Fusion and Plasma Physics

基　　金：国家自然科学基金资助项目(11975264);国家重大科技基础设施建设项目-聚变堆主机关键系统综合研究设施(2018-000052-73-01-001228)。

摘　　要：中性束注入是磁约束核聚变能研究中重要的辅助加热手段。大面积负离子源是中性束注入系统的核心部件。在负离子源工作过程中,负离子的电子结合能非常小(约0.75e V),极易被高能电子破坏。为此需要设计过滤磁场降低电子温度,减少负离子的损失,同时也可以减少伴随引出的电子。根据大面积负离子束源的机械结构,分别设计了永磁体产生过滤磁场和利用等离子体电极(PG)电流产生磁场两种磁过滤器结构;通过有限元算法对产生的过滤磁场进行模拟分析和优化,完成了大面积负离子束源过滤磁场的研制。在负离子束源测试平台开展实验测试,引出区电子温度从5eV降至1eV。这个结果初步验证了大面积负离子束源的过滤磁场的性能,为大面积负离子束源的研制提供了支持。Neutral beam injection is an important auxiliary heating tool for magnetic confinement nuclear fusion research.Large area negative ion source is the core component of the neutral beam injector.When the negative ion source works,the negative ions are easily destroyed by electrons with high energy due to the low electron binding energy of negative ions(0.75eV).Therefore,a magnetic filter field should be introduced to decrease the electron temperature.And then the loss of negative ions can be reduced,and the component of co-extraction electron can also be decreased.According to the mechanical structure of the large area negative ion beam source two kinds of magnetic filter structures are designed respectively.One is produced by permanent magnet,the other is produced by the current through the plasma grid(PG).Through the finite element algorithm,the magnetic filter field was analyzed,tested and optimized on the negative ion beam source prototype.The electron temperature was decreased from 5eV to 1eV in the extraction region.This result verifies initially the performance of magnetic filter field for large area negative ion beam source and could support the development of large area negative ion beam source.

关 键 词：过滤磁场 中性束注入 等离子体电极 负离子束源 

分 类 号：TL629.1[核科学技术—核技术及应用]