Research On The Control System Of Digital Welding Machine

With the appearance of the new materials and the development of the new technology and process, welding power source is required with higher level. But, most of the domestic welding machines adopt the power source of analog structure, and it becomes more and more difficult to meet the need of complicated welding process at present. The key to solve the problem is digitalization. So, the development of digital welding power source is the main trend.The main research of this article is about the digitalization of the controlling circuit. The controlling circuit use the combination of the MCU(Microcontroller) and DSP(Digital Signal Processor) to get control. The control system is programmed to meet the need of the requirement of the welding process of the basic welding method, such as MIG, Pulse MIG and so on, with the same hardware. Besides supervising the system, MCU control system takes charge of the display of the current and the arc voltage, the communication with PC and the control of other assistant equipment.The following is the process. Through the man-machine interaction system which consisted of LCD (Liquid Crystal Display) and keyboards, we can select welding parameters, such as the way of welding, diameter of the wire, wire feed speed, current, voltage and so on. In the closed loop, the information is transmitted to DSP from MCU and compared to the feedback data. Then, the result would be transmitted back to the MCU for adjusting the WFS, voltage and so on to the setting values. At the same time, the feedback date is transmitted to MCU for displaying on the control panel. The welding parameters could be loaded to the MCU from the professional welding database in the PC by the communication between them.