Scheduling Algorithm in Networked Control Systems Based on Importance

In order to enhance the performance of networked control system, a novel scheduling algorithm is proposed. MCF (maximum-change-first) which is the simplified MEF-TOD is used to design the basic priority, and then, LDLP (larger-delay-lower-priority) strategy is used to dynamically adjust the priority of the message. In the view of the importance of the message, the new scheduling algorithm called MCF-LDLP gives a more sound foundation to design the priority. The EDF, MEF and MCF-LDLP are simulated and the results are compared in IAE, settle time and override which showed that although the proposed scheduling algorithm discard more messages, the overall performance of the control system are better than the others, even under the circumstances of an over-loaded network or severe disturbance.