Plasma boundary identification is a basic task for studies on equilibrium and confinement in a divertor tokamak. With the progress on the experiments after engineering experiments, the boundary identification becomes an important issue for HL-2A. In order to satisfy the requirements of preciseness, simplified measurements and quickness, the filament current method instead of solving the equilibrium equations is used to identify plasma boundary on HL-2A. The involved principle, mathematics and the progresses, which have been made with this method, are given.
为了研究HL-2A等离子体偏滤器位形,研制了等离子体形状实时显示系统.采用固定位置电流丝和有限电流元的方法编写了CF编码.采用32道同时刻采集器UA301采集等离子体周围的磁场信息,使用P43GHz E CPU组装的兼容计算机处理数据.这个系统每4ms采集一次数据并存盘,每16ms重画一次等离子体边界.放电结束后可以详细地计算等离子体边界及其磁场以及由此导出的等离子体参数.
The Ethernet and field-bus communications are used in the machine control system(MCS) of HL-2A. The control net, with a programmable logic controller (PLC) as its logic controlmaster, an engineering control management station as its net server, and a timing control PCconnected to a number of terminals, flexibly and freely transfers information among the nodeson it with the Ethernet transmission techniques. The PLC masters the field bus, which carriessmall pieces of information between PLC and the field sites reliably and quickly. The control netis connected into the data net, where Internet access and sharing of more experimental data areenabled. The communication in the MCS guarantees the digitalization, automation and central-ization. Also provided are a satisfactory degree of safety, reliability, stability, expandability andflexibility for maintenance.
