中文摘要：

介绍非线性参量近似熵的理论及算法，提出由近似熵的角度去分析短路过渡弧焊稳定性的思想，对指导实际焊接过程时的规范选择有参考作用。在焊接参数均满足匹配条件下，采集短路过渡的弧焊电流信号，对该电流信号的近似熵进行计算，结合传统的最佳电弧的理论认识，通过比较不同规范下近似熵的大小和近似熵的标准方差，探索得出近似熵与稳定性的规律。结果表明最佳的焊接规范具有近似熵较大，标准方差较小的特征，且在最佳的焊接规范中标准方差最小就对应着最佳电弧。

英文摘要：

The theory and related algorithm of the nonlinear parameter approximate entropy are introduced. A method for analysing the stability in short-circuiting transition arc welding is put forward based on approximate entropy, which can be helpful to select the welding conditions. With welding variables matched, the current data in short-circuiting transition arc welding are acquired and the approximate entropy of current is calculated. Referring to the traditional theoretical analysis of the best stable arc, the association features between approximate entropy and stability are studied by comparing value and standard deviation of approximate entropy. The results show that the better welding conditions are characterized by larger approximate entropy and lower standard deviation, and the lowest standard deviation among the better matching welding conditions indicates the best stable arc.