高速旋转电弧传感器的数学模型

以气保护焊接系统的数学模型和HALMOY焊丝熔化模型为基础，对高速旋转电弧传感器进行数学建模。利用该数学模型模拟焊接电流、弧长和焊丝伸出长度随时间的变化规律。实际焊接试验显示，模拟焊接电流与实际焊接电流波形高度吻合，说明建立的数学模型是准确的。结果表明，高速旋转电弧焊接时，弧长的变化较焊丝伸出长度的变化更为显著。利用每个电弧旋转周期内左半周与右半周平均电流值的差，可以判断焊枪的偏差量及其方向，同时还可根据平均电流值的大小来检测角接终止点。所建立的模型对于高速旋转电弧传感系统的设计具有指导意义。

MATHEMATIC MODEL OF HIGH SPEED ROTATIONAL ARC SENSOR

A mathematical model of high speed rotational arc sensor, which is used in gas metal arc welding (GMAW) of fillet joints, is developed. It is based on the mathematical model of GMA welding system and Halmoy's wire melting model. The variations of welding current, arc length and wire extension are simulated by using the developed model. It is shown that the simulation results of welding current, arc length and wire extension agree with the experimental results in fillet joints. Based on the mathematical model, the variation of arc length is bigger than that of wire extension. The deviation and direction of the welding gun can be detected by the difference between the left half-cycle current and the right half-cycle current during each torch rotational cycle. In addition, the end point of the fillet joint can be detected by the average current value in each torch rotational cycle. The mathematical model developed is helpful to the design and application of high speed rotational arc sensors.