Abstract: In light of the primary grinding circuit of a concentrator, a fuzzy control system for grinding mill feed quantity based on S7-300 PLC and Wincc was designed.The system adopts a set value fuzzy control and fuzzy PID control algorithms to set the mill feed quantity and timely set K_P , T_I , T_D parameters, well realizing the stable control of the feed quantity for the primary grinding mills of this concentrator.

Key words: Grinding mill feed quantity, Set value fuzzy control algorithm, Fuzzy PID control algorithm, S7-300 PLC, WinCC