Reaserch On Variable Samping Period Of Network Control System For Dynamic Secheduling

With the rapid development of Internet applications, the Internet application system has entered every aspect of our life,such as IOT、CPS、 AIS, can not do without a variety of network communications. Secondly,in some new industrial systems,such as PMS、CAES, the data in the processing control system are of high urgency, namely, the data requirements have a higher real-time, from the point of view of the composition and spatial distribution, these industrial systems are for the network of control system, namely data using transmission network as a carrier for transmission, the process control technology and computer processing technology integration into a remote distribution of the closed-loop system.Firstly, the paper expounds background of NCS,basic structure, application and the basic problems, and then introduces the basic concept of NCS scheduling, leading to the problem of scheduling.In this paper, the nodes with multiple control loops in the network environment on the co occupancy under the limited network resources, reasonable allocation of limited network bandwidth resources and online operation how to dynamically adjust the send priority problem of multiple transmission tasks are analyzed, and the introduction of an online dynamic adjusting method for transmitting node priority-EDF, the algorithm in practical application in online operation, can through the decision task transfer distance transmission cut-off time length dynamically allocated transmission task sends data packet priority, reasonable allocation of network resources, provide a good network environment for NCS.Considering the control performance of NCS and the sampling period of network quality sensor, a dynamic adjustment model based on Matlab-ANFIS sampling period is proposed, which is NCS-SPDS. In this model, the adaptive fuzzy inference theory is applied to to control loop sampling period of adjustment, to build a three control loop NCS simulation model, and at the same time introduced EDF on resource constrained scheduling, simulation analysis verified to improve the network environment, overcome the shortcomings of existing scheduling strategy, the system’s overall quality control has been greatly improved.Finally, in the PMS, by dynamically adjusting the sampling period to verify the effects of photovoltaic micro grid energy bi-directional converter PQ, VF, mode switching performance, from the experimental analysis that traditional prediction algorithm of least square method in use to meet a good real-time and control performance to meet the normal operation of the system, also ANFIS algorithm although has better control performance, but the large computing delay unable to meet photovoltaic micro grid system operation.