Abstract: In this paper,A newly developed wire feeder control system with upslope output characteristic has been discussed and tested.The test results showed that:① If the amplifying coefficicnt,Ki,of positive feedback from armature current to the system output voltage is equal to the armature internal resistance,Rs,the rotating speed of wire feeding motor will be independent of the change of load.②Control system compcnsation must be carried out for eliminating the system unstabilily or oscillation at the point of Ki=Rs and in the region about Ki=Rs.The principle of choosing the parameters for the compensation device is given.The performance of wire feeder using this newly developed control system is much better than that using the convenlional one.