Research On The Multi-task Scheduling For The Process Control System Of The Single Stand Reversible Cold Rolling Mill

Single stand reversible cold rolling mill has been more and more widely used becauseof the advantage of the high stiffness of its roll system, the large rate of screwdown afterevery pass, the high accurate of the products. During the cold rolling production process,the quality of the process control system of the single stand reversible cold rolling milldetermines the quality of the output strip and the rolling production efficiency. Sodeveloping the process control system software is meaningful. What’s more the core issuein the process control system development is the multi-task scheduling problem. So thispaper’s target is designing a reasonable multi-task scheduling method for the processcontrol system of the single stand reversible cold rolling mill. In order to achieve thetarget following work is done.First, this paper made the division of functions for the process control system of thesingle stand reversible cold rolling mill according to cold rolling producing technology.And then this paper made the functional design for process control level.Second, this paper designed material tracking module which is most closely relatedto multi-task scheduling problem. What’s more material tacking module’s fullfunctionality has been achieved by programming. The correctness of the design has beenverified.Finally, this paper researched on the concurrent multi-task in the process controlsystem of the single stand reversible cold rolling mill. A control method based on thesemaphore has been designed to solve mutex and synchronization of multi-task. Amultithread method has been put forward to improve the efficiency in the implementationof measured values’ treatment module. This paper researched on the serial multi-task too.A control system for serial multi-task based on finite automata has been designed. Thispaper made a division for multi-task by priority according to the multi-task’s degree ofimportance and degree of urgency. The method for multi-task’s processor scheduling hasbeen designed by combining multi-task’s priority and three scheduling policy includingsampling time scheduling, event-driven scheduling, time slice scheduling.Currently domestic research on the multi-task scheduling technology stays on thetheoretical level, while applied to the actual control system are rate. Therefore, theresearch on the multi-task scheduling solutions for the process control system of the singlestand reversible cold rolling mill in this paper combined multi-task scheduling theory andcold rolling production. The research had practical application value and reference valuefor similar control system.