Abstract:

In order to study the optic characteristics of 80kV/40A/5s hot-cathode ion source of neutral beam injector (NBI) on HL-2M tokamak, Charge-coupled Device (CCD) infrared thermography technology was used to measure the temperature distribution caused by the beam bombardment on the calorimetric target and the feature parameter (1/e half width) of beam power distribution was obtained. On the NBI hot-cathode ion source platform, the discharge and extraction parameters of the ion source were scanned, and beam power distributions on the calorimetric target were obtained. The experimental results show that the available perveance range of 80kV/45A ion source on HL-2M NBI system was 0.7~1.5μP. In the same perveance, when the voltage ratio of the gradient electrode to the plasma electrode is higher, the half width of the extraction beam power distribution is smaller.

Key words: HL-2M tokamak, Neutral beam injector ion source, Perveance, Infrared thermography

摘要：

为了研究HL-2M装置中性束注入(NBI)加热用的80kV/45A/5s热阴极离子源束光学特性，采用红外电荷耦合元件(CCD)成像技术，测量离子源引出粒子束轰击量热靶板产生的温度分布，得到束功率密度空间分布区间特征参数1/e半宽度。在NBI热阴极离子源调试平台上，扫描离子源的放电和引出参数，利用CCD红外热像仪获得了对应参数下量热靶上的束功率密度分布。实验结果表明，HL-2M装置NBI加热系统80kV/45A离子源可用的导流系数范围为0.7~1.5μP。同样导流系数下，梯度电极与等离子体电极的分压比较高时，引出束流的半宽度较小。

关键词: HL-2M装置, 中性束注入离子源, 导流系数, 红外热像仪