基于有源缓冲网络的高频GMAW设备设计

Design of High Frequency GMAW Equipment Based on Active Snubber Circuit

设计了一套高频熔化极气体保护焊接设备。主电路主要由两套并联的电路组成,通过PIC单片机控制两支开关管导通与关断来切换高频脉冲电流,通过程序控制电源输出电流的大小。设计了一套有源缓冲电路用于吸收主电路开关管两端的尖峰电压,既保证主电路安全工作的同时,又把开关管两端的尖峰能量反馈至主电路重复利用。经测试,设计的高频焊接设备峰值电流I_p可调节至150 A,基值电流I_b可调节至360 A,电流频率可调节范围为5~20 k Hz,脉冲电流可达到很快的上升及下降速度。采用此设备进行了Q235碳素结构钢的焊接工艺试验,焊缝成形良好。

A set of high frequency gas metal arc welding （GMAW） equipment was designed. The main circuit was composed of two parallel circuits, the switching of high frequency pulse current was controlled by PIC single chip microcomputer controlling two switch tubes on and off, and the output current of the power supply is controlled by program. A set of active snubber circuit was designed to absorb the peak voltage at the two ends of the main circuit switch tube, and it can not only ensure the safety of the main circuit, but also feed back the peak energy at both ends of the switch to the main circuit for reuse. After testing, the peak current Ip of the designed high frenquency welding equipment can be set to 150 A, the base current Ib can be set to 360 A, the current frequency adjustable range is 5-20 kHz, and the pulse current can reach very fast rise and fall speeds. The welding process test ofQ235 carbon structural steel was carded out by using this equipment, and the weld is well formed.