波形控制CO2焊接逆变电源—电弧系统的仿真研究

由于短路过渡CO2焊接电弧负载的非线性与时变性的特点，CO2焊接电源－电弧系统的研究与设计有其固的难点，采用在控制领域最具影响的MATLAB软件，在对CO2焊接电弧建模、逆变电源－－电弧系统建模的基础上，仿真了波形控制CO2焊接逆变电源－电弧系统的动态过程，并且在模拟示波器上输出了CO2焊接电弧的几个典型参数的动态波形，通过计算机仿真，提出了CO2焊接焊丝熔化速度与送丝的平衡长度的概念，揭示了焊丝平衡长度的物理过程，这对研究CO2焊接过程有重要意义，给出了评价计算机仿真CO2焊接过程正确与否的基本原则，即CO2焊接焊丝平衡长度的变化范围必须是大于0，最大值是几毫米（具体值与焊接参数有关）的数量程度，给出了波形控制CO2焊接逆变电源－电弧系统的控制结构，通过仿真可以看出短路过渡CO2焊接逆变电源控制参数对系统的影响规律，辅助优化设计系统。

Study on inverted power-arc system of wave-controlled CO2 welding with computer simulation

It is difficult to study and design th e CO2 welding power -arc system due to the s hort transfer of CO2 welding which has nonlinear and instantaneous characteristics.This paper studies the dynamic process of th e CO2 welding invert power -arc systembased on the modeling of CO2 welding arc and the modeling of invert power -arc system with MATLAB software.At the s ame time,several representative wa ves of CO2 welding arc are showed on the simulation scope.Anew concept i s put forward to deal with the balance between the speed of wire melting and the speed of wire supplying,and this new concept is called balance length,which is important to discover the physics principle of wire balance le ngth and study the process of CO2 welding.This paper also offers a principle to access the validity of CO2 welding process based on computer simulation.The balance length should be designed between 0mm and several millimeter(this numerical value is accordance t o the welding parameter),A type of structure of wave -controlled CO2 welding invert power -arc is simulated to disclose the law of the effect on the power -arc systemand welding parame ter on the CO2 welding systemprocess,to aid optim izing the systemdesign.