Abstract: This paper describes the technical requirements,structure of electrical control system,and technical characteristics of the control system of the acrylic fiber production line.Targeting the regulation problem of the tension roller system of its control system during production,the theory base and design method of the closed loop PID regulation system are introduced.Based on the tension roller system mathematical model,the MatLab simulation is used to verify the correctness of the closed loop regulation system.The real-time monitor results show the feasibility of the closed loop system in practical engineering.