基于模糊逻辑的电阻点焊恒流控制系统

CONSTANT-CURRENT CONTROL SYSTEM OF RESISTANCE SPOT WELDING BASED ON FUZZY LOGIC

研制了用于电阻点焊的模糊控制系统。本系统以Intel80C196KC单片机为工具 ,采用了模糊控制的算法 ,能够补偿各种干扰对焊接过程中电流的影响 ,使其保持恒定 ,从而保证了点焊的焊接质量。模糊控制器以焊接过程中焊接电流输入值和输出值的偏差及偏差变化率为输入 ,以焊接主回路中晶闸管调整角为输出。结果表明 ,该系统性能稳定 ,与常规的PID控制相比 ,性能优越 ,能有效地保证焊接过程中的电流恒定 。

The article studies a fuzzy logic control system for the resistance spot welding. The system adopting the single-chip microcomputer of intel80C196KC as the core tool and fuzzy logic as the adjusting way can compensate for the all kinds of influences on the welding current and make the current constant in the welding process, thus it can guarantee the quality of the welding. The difference between the effective value of current and preset value of current as well as the variation of the difference as two input variables to control and adjust the angle of flow of thyristors that are in the welding main return circuit. The results of the experiments show that the system, compared with the general PID controller, is more stable and can keep the current constant in the welding process, and then guarantees the quality of the welding.