表面张力过渡动态过程的仿真

在分析短路过渡、熔滴受力以及表面张力过渡控制理论的基础上，建立了表面张力过渡动态过程的数学模型及仿真模型。系统地分析了送丝速度、熔化率、熔滴的变化对弧长的影响，并建立了其数学模型。比较了在表面张力控制区内选择不同的电流控制方式时对焊接系统动特性的影响。对仿真模型进行了试验验证，仿真结果与试验结果基本吻合，证实了模型的正确性。试验结果表明，采用输出斩波控制方式较逆变环节控制方式能够更快速地将电流减小以满足表面张力控制的需要。

Dynamic process of surface tension transformation (STT)

By analyzing the short circuit transformation, the forceacting on droplets and the control theory of the STT, a mathematical modeland a simulation model of the STT dynamic process were established. Itanalyzes systemically the influence of wire feed speed, melting rate andthe variations of droplet on arc length, and founds its mathematical model.This paper also compares the influences of different control mode of thecurrent on the dynamic characteristic of the welding system in the STT pe-riods. Different simulation models were taken into experiment, the simula-ted results corresponds with the experiment results, which proved the SIM-ULINK models to be correct. The results show that output control modecan reduce the current more rapidly to meet the need of STF control sys-tem than invert-loop control mode.