Development Of Network Based Resistance Spot Welding Controller

A kind of spot welding controller that can communicate by Ethernet has been developed on the background of automobiles production line, in order to solve the collision of control and communication time sequence, this controller has two SCMs, one charges for controlling spot welding process, the other is in charge of the communication spot welding process information and spot welding quality information between spot-welder and PC.The two SCMs implement data exchange by shared memory.On the side of spot welding software, not only the past voltage compensation and constant current algorithm which ensures spot welding quality are reserved, aiming at spot welding material with obvious dynamic resistance, but also the feedback control algorithm of dynamic resistance is designed on the basis of mode of heat percentage, and then the specific TCP state transition chart is established aiming at SCM and PC on the basis of normal TCP state transition chart, which is used to monitor soldering machine working situation in the real-time and long-distance way.Finally the three kind of control algorithms are verified by numerical method, the data show that they can control welding quality perfectly, the communication programmer is tested by professional monitoring software, the analysis of rock-bottom data indicates that the design thought not only makes the burden of network small and data transfer quick, but also can eliminate kinds of abnormal situation in the process of practical spot welding data transfer.The development of network based resistance spot welding controller can control the process of spot welding and realize the long-distance sending and monitoring of welding parameter, thereby the quality of spot welding is ensured and the demand of spot welding industrial development is satisfied.