波控CO2短路过渡焊逆变电源电弧系统仿真

Simulation of CO_2 Short-circuiting Welding under Waveform Control on Inverter Power Source

针对CO2气体保护焊短路过渡过程具有非线性和强时变性等特点,采用MATLAB仿真软件对逆变电源-电弧系统进行了仿真。仿真研究中,在波形控制的基础上,采用了恒流控制。对电流反馈信号和电压反馈信号分别进行了模拟仿真,利用逆变电源中的PWM控制方式来改变占空比的大小,从而改变电源的输出。给出了CO2焊短路过渡过程中电压和电流的动态波形。通过仿真可看出,波形中存在着逆变谐波的影响。仿真波形与实测波形基本一致,该结果为以后深入研究谐波以及随机干扰对电源控制过程的影响奠定了基础。

According to the character of the non-linearity and timed-denaturation of short-circuiting transfer in CO2 gas shielded arc welding, the inversion power-arc system was simulated by usage of the waveform control and the MATLAB simulation software.Based on the waveform control,the constant current control,feedbacks of current and voltage were taken at the different time during the simulation process.The duty ratio was changed by the PWM control in inverter power source to change the output of power source.The dynamic waveforms of voltage and current in the process of CO2 short- circuit transfer welding were outputted, which had embodied the effect of inversion harmonic wave.The simulation wave is identical with the true waveform.The simulation result establishes the foundation for studying the effect of harmonic and random interferences on control process of power supply.