The Research On Control System Of The Intermediate-frequency Inverter Of Spot Welding Based On STM32

Since inverter power has advantages over others, including small volume, lightweight, high power factor, high control accuracy and so on, it has become thedominent researching direction of resistance spot welding power source. It istheoretically and practically valuable for the accomplishment of inverter process ofinverter spot welding machine and intelligent control of welding spot quality. Afteranalysising the spot welding control system, the article has designed fuzzy controllerbased on interpolation algorithm, in order to realize the spot welding constant currentcontrol. The simulation results, with the help of MATLAB software, show that thesort of controller is characterized by fast response speed, high stead accuracy, smallovershot and is superior to the traditional fuzzy controller in control effect.With theexpanding scale of industry production, the problem of information transfer amongdevices is more and more evident, which largely restrict the automation of workshop.However, the emergence of CAN bus well solves the information isolation. Thearticle introduces CAN bus into the spot welding control system and dealing with thedata communication problem between spot welding controller and PC. It aims toaccomplish automation control of spot welding in process as well as the detectionand management of multi-parameter information, and, eventually, to realize thenetwork production of spot welding workshop.The article has accomplished the design of peripheral circuit centre on STM32, including the IGBT driving circuit, starting circuit of welding,detection and processingcircuit of welding, water pressure start-up circuit, communication circuit of lower level CAN controller and the hardware circuit of PC CAN communication interface cardof PCI-6820.The design of the controller system software adopt the sense of modular, whichis divided into three parts: the initialization of STM32F103ZET6in the CANcontroller and the message receiving as well as sending procedures; the proceduredesign of PCI-6820adapted to PC CAN interface card and the visualizing interface ofPC; the detection of welding circuit as well as data processing.According to the research, the sort of spot welding control system based on CANbus has met the demands of spot welding control in process. The accomplishment of this research will play an important role in promoting the intelligentization and networking of spot welding in process.