Research Of The Spot Welding Control System Based On Modularization

At present, resistance spot-welding technology has already become an indispensable part in modern industrial production. It has stronger welding capability and rapid welding speed. However, some conditions, such as environment, temperature and humidity, etc. will affect welding effects. Moreover, interactive nugget forming process can be observed with the naked eye. It is a kind of multifarious dynamic thermal process. In order to ensure high benefit and high quality for welding, it is necessary to research a kind of control monitor with high welding precision and strong universality. With the intellectualization of control technology, welding quality control has considerable progress. Control methods are expanded to Fuzz Control, Fuzzy-PI Control, Model Reference Fuzzy Adaptive Control, and Fuzzy Neural Network Control, etc. The extensive use of the above-mentioned methods certainly will drive the further development of spot-welding control system.By beginning with the system composition of electric welding, the task regards inverter AC resistance welding system as the primary power system. By analyzing characters and principles of inverter AC resistance welding and extracting key parameters of power supply, the task confirms that electric current is the principal controlled object. By analyzing characters of the controlled object and combining with characteristics of various control methods, the task adopts Fuzzy PID control strategy and obtains a good control effect. In system implementation, master controller considers FX3 UPLC as a hard core control device. By combining with matched spot-welder’s welding starting signal circuit, clock circuit, silicon controlled trigger circuit, etc. peripheral circuits and control programs, the task completes the design of electric-welding control system and improves system’s anti-interference from multiple aspects of circuit design and circuit protection in implementation process.