变极性等离子焊设备控制系统研究

Investigation of control system of welding equipment with polarity-variable plasma arc

根据变极性等离子焊机的发展方向,提出了双电源等离子焊设备的设计方案,其中主电路采用逆变技术,控制系统则采用单片机控制技术代替传统的模拟控制技术.通过控制定时器8253的输出改变IGBT的通断时间,实现对变极性等离子弧焊设备电流频率、正负半波导通比的调节和控制.实验表明,以单片机80C552为核心组成的变极性等离子弧焊设备控制系统硬件设计简单,调节方便,显著提高了系统的可靠性.

According to the trend of VPPAW equipment, a design scheme is introduced in which the welding machine is supplemented with double power sources, the main circuit being a inverter and the control system adopts singlechip technology instead of traditional analog technology. By using the output of the timer 8253 to change IGBT's on/off time, current frequency and DCEN/DCEP ratio are adjusted and controlled in VPPAW equipment. The tests show that the VPPAW control system with a monolithic computer 80C552 as its core is simple in hardware configuration, convenient to be regulated, and remarkable for improving the system reliability.