Abstract: In order to reduce dependence of operating skill, fuzzy control system is developed, the core of which is a 16 bit single chip microcomputer of Intel 80c196kc. It is realized by software programming. In this system two fuzzy controller are designed. The PID parameter selfadjusting fuzzy controller is used to compensate welding current deviation in the process of are voltage optimized control. To obtain the optimum result of ultimate frequency of short circuit transfer, the self-optimizing fuzzy controller carries out the are voltage self-optimizing by under the condition of the given welding current. Are voltage and welding current are kept the optimum matching relationship by two fuzzy controllers.

Key words: CO2 short circuit transfer welding, Fuzzy control, Operations skills, Single chip microcomputer