用有限电流元法识别HL-2A 装置的等离子体边界

在电流丝模型对HL-2A装置等离子体边界重建取得满意结果3]、5]的基础上，本文用有限电流元模型对HL-2A等离子体边界进行了重建研究。计算和实验结果表明，在通常情况下，有限电流元模型比固定电流丝模型的重建误差稍小，前者误差小于3mm，后者误差小于6mm。当部分有限电流元分布在等离子体边界之外时，用有限电流元模型仍然可以成功重建边界。有限电流元的位置在一定范围内变化时，重建的误差都很小。用普通奔腾4 2.4GHz PC机计算一组等离子体放电边界的时间不超过1ms。有限电流元法能准确而快速地识别等离子体的偏滤器位形，这对于HL-2A装置的实时位形控制是基本和重要的。

Plasma boundary identification in HL-2A by means of the finite current element method

In this paper, the finite current element (FCE) method used in HL-2A is described. The calculation and test results show that the error of the reconstructed boundary given by the FCE method (<3mm) is smaller than that obtained by the current filament method used before (<6mm). Even if some current elements are located out of the plasma boundary, the FCE method can also identify the plasma boundary successfully. If the location of the finite current elements is changed in a certain area, the error of the reconstructed boundary is always very small. By employing a conventional PC (Pentium 4 2.4GHz), the calculation time of one set of plasma discharge parameters does not exceed 1ms. Thus, the FCE method can identify the diverted plasma configuration quickly and accurately. This is essential and important for real-time shape control in HL-2A.