Development Of The MCU System Of Digital Welding Power Source Basing On Dual-processor Control

Production becomes faster and more efficiencent as the welding technology is widely used. This may need high quality welding power source. The digital welding power source, which is the developing direction of this field, now becomes a frontal subject as the automatic and intelligent technology develops.This paper analyses the research status of the digital welding power source inside our country and abroad. A dual-processor control digital welding power source basing on MCU + DSP structure is developed in the aim of perfecting the digital welding power source system and making full use of its advantages. This power source can be used for CO2 welding and other welding methods. The MCU system is fully developed according to the requirements of the dual-processor control digital welding power source. Both hardware and software of the MCU system is established and the man-machine interface is designed. The interface adopts net structure, which adds guide function to the traditional tree structure. Thus, the interface can jump to any page easily. The selection of the welding machine parameters, the setup and saving of the welding parameters, the real-time change and display of these parameters are all realized. The man-machine interface has several advantages, such as functional multiplicity, operational agility, and so on.The scheduling control function is realized in this design and the 2-step and 4-step operation modes are also designed.The hardware and software of the communication interface between MCU and DSP is designed and a communication protocol is made, which ensure that steady communication is available. The communication between the MCU and the upper computer is also discussed and an upper computer control interface is designed. A wire speed control system is designed adopting the PI control strategy. The model of this wire speed control system is established using the Simulink software. The PI parameters are fixed on by simulation and real experiment separately.Experiment results show that the MCU system can realize the man-machine interface function and the scheduling control function .The wire speed is accurate. The MCU system developed in this paper can meet the requirements of the CO2 welding method, and it also provides a platform for multifunctional digital welding power source research in the future.