EAST-NBI离子源电极打火分析及处理  

Analysis and processing of breakdown of ion source for EAST neutral beam injector

作　　者：许永建 张黎 谢亚红[1] 蒋才超 梁立振 胡纯栋[1] 

机构地区：[1]中国科学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：《核技术》2017年第11期73-77,共5页Nuclear Techniques

基　　金：国家自然科学基金(No.11405207、No.11675215);中国科学院等离子体物理研究所基金(No.DSJJ-15-GC03)资助~~

摘　　要：强流离子源是EAST(Experimental Advanced Superconducting Tokamak)中性束注入器(Neutral Beam Injector,NBI)最关键的核心部件,其能达到的性能在很大程度上决定了EAST中性束注入器所能达到的指标。离子源在束引出时电极打火现象偶有发生,这对于离子源的正常运行有非常严重的影响,甚至危害离子源的寿命。本文结合离子源运行过程中的束引出实验波形和水流量热计(Water Flow Calorimetry,WFC)系统的测量数据得出等离子体发射面的束流光学系统一直处于非最佳聚焦状态是导致打火的原因,试通过优化高压投入时刻等离子体与高压的匹配,实现高压的稳定投入有效抑制打火现象的发生,并且给离子源加入硬件保护机制,为离子源安全稳定运行奠定基础。Background： The high current ion source is a key component of neutral beam injector, and its reachable performance determines the achievable targets of the experimental advanced superconducting tokamak （EAST） neutral beam injector （NBI）. Electrode breakdown of ion source happens occasionally during the beam extraction, which has a very serious impact on the normal operation of ion source and even endangers the life of the ion source. Purpose： This paper aims to analyze the reason of breakdown and propose improvement measures. Methods： The waveforms of beam extraction and the data of water flow calorimetry （WFC） of the abnormal shot of 7801 and normal shot of 7799 were studied. Results： The analysis shows that the cause of breakdown is the dual effect of over-focus and under-focus of extraction beam. Optimizing the matching of the plasma and the high pressure can effectively reduce the phenomenon of breakdown, and in order to protect ion source, a hardware protection mechanism is added. Conclusion： The analysis results lay a foundation for the safe and stable operation of ion source.

关 键 词：离子源 束引出 电极打火 水流量热计 

分 类 号：TL654[核科学技术—核技术及应用]