Distributed Synchronization Control System Design And Software Implementation

Nowadays,along with the development of science and technology,the communication of internet technology and computer technology has been applied in industry,agriculture,business and other fields,produced huge convenience and economic benefits.In the fields such as industry,aviation,communication,open,distributed,heterogeneous distributed system due to the huge advantage of resource share,high availability,parallel processing and so on,become the mainstream of modern computer application system;Especially large-scale production,it is the typical application examples that information technology and control technology.But along with the continuous expansion of the system,the constant improvement of the evolution and maintenance requirements,as well as the distributed control system characteristic of distribution,autonomy and heterogeneity become the primary difficulties of the development of long plagued and restriction.Much research and practice shows that the distributed control system and the computer software architecture in combination with each other,to guide the implementation of distributed control system with the software system and operation,which can effectively solve the DCS's software system's complexity,the defects such as poor maintainability and long development cycle,improve the quality of the software,makes software development and extension,reuse and maintenance in simplification and modularization,the realization of the distributed system was constructed successfully.Now,the field of industrial control,generally uses the C/S(Client/Server)mode of distributed control system,the control system,the Server must respond to the request comes from the operator,the Client,its' application,request the Server's performance must be very high,and if the Client to the Real-time demand is high,may cause the request timeout,causing the Client operation failure and lead to the entire control equipment or system paralysis.Industry solution to this situation is generally adopted improve server performance or set the time limit of the client's request is bigger,it may temporarily alleviate the problem,but can not fundamentally solve the problem.Therefore,how to improve the real-time distributed system through the software system structure and the ability to quickly handle response,guarantee the validity and reliability of the system system,is the key to the distributed system development,also is the core content of this study.In view of the above situation,this paper puts forward a kind of synchronous Control mechanism based on Distributed systems,as a Distributed Synchronization Control system(Distributed Synchronization Control system,DSC),and on the in-depth research,design,and application instructions,specific work is as follows:(1)According to the distributed system and synchronization control is put forward which combination of DSC,the system is mainly used to coordinate various Clients(control system for the Subsystem(short for SS)or Bottom Component(short for SS))collaboration,SS of the synchronous(in this article the so-called synchronization,only refers to the time synchronization,which at the same time,SS began to perform their respective action)at the same time to complete the operation of the user.In this paper between the Client and Server to increase a Synchronous Control Module(SM for short),used for SS synchronous Control and management: explanation and the commands issued by the Server,accepted and comprehensive result of SS reply.(2)The design of the work mode of DSC: Server will user commands directly to the SM,the SM is responsible for the command parsing,for each SS,issued after parsing different command;When SS execution after the completion of the action,will be in the form of "events" to inform SM,SM for SS the execution result later.SM in issued an order at the same time,will start the timer,tag from the command issued to receive each SS in response time,when more than a certain time(after general Settings for the 30 s),will stop waiting,and did not return the SS reset;If a SS perform error,SM integrated all SS the results,this command execution report Server error,according to the error information positioning errors of SS,to reset the SS,or other operations.(3)This system adopts the clock synchronization system,to provide a common clock for the whole system,all SS this clock as a time reference,perform all actions for this clock frequency of integer times.This avoids the distributed control system in each Client individually,clock a various problems caused by the different,make the whole system time "normalization",effectively improve the effectiveness and precision of the system control.(4)We design a "Synchronous Diagnosis" way(short for SD).To perform an action in the process,if a SS error happens,can be directly sent via bus synchronous diagnostic error message refers to the SM,the SM concludes that the level and nature of the error,if influence to the whole system running,will immediately notify the other SS stop to perform an action,and report Server error the execution;If the SS error level is lower,will directly to ignore this error.By this way,can avoid system running under the error status,cause needless loss.(5)Using universal network protocol Socket,complete the communication between Server and SM,SM and SS,SS.Based on the existing network protocol,to avoid the development of network components,greatly save development time of the system.