Networked Control Systems Based On Modified Fuzzy Immune PID Control

As the introduction of the communication networks, the data transmission between the nodes of the networked control systems will cause the delay and the packet loss, the size of the network delay has the relation with the network protocols, system architecture and the network loading and so on. The network delay may reduce the control performance of the system, and even let the system to be instable.Since that the conventional fuzzy immune PID control cannot resist the dynamic interference which affect the system performance or eliminate the static error of the system well, in this paper, we make a simulation comparative study between these two modified fuzzy immune PID control algorithms and the conventional fuzzy immune PID control within the NCS environment of the Truetime, for verifying the validity of the improved algorithm.First of all, to the improved fuzzy immune PID control algorithm (a), we apply it to the NCS and make the simulation study. This algorithm will use the feedback control law to adjust the proportional, integral and differential parameters of the controller while maintain the fuzzy immune control rules constant. The results show that when compared with the conventional fuzzy immune PID control of NCS, the NCS which based on the improved fuzzy immune PID control algorithm (a) could improve the control ability and the quality of control performance of the system furthermore, and can achieve better control effect.Second, we bring an improved fuzzy immune PID control algorithm (b) which may apply to the NCS. This algorithm uses the fuzzy control rules to instead of the rule of fuzzy immune control, and utilize the immune feedback control law to adjust the proportional, integral and differential parameters of the controller respectively. Simulation study have shown that when compared with the NCS with the conventional fuzzy immune PID, the NCS with the improved fuzzy immune PID control algorithm (b) could improve the dynamic response and enhance the control performance of the system by extending the fuzzy immune control rules.At last, we make a simulation comparative study between these two modified fuzzy immune PID control algorithms within the WNCS, for verifying the validity of the improved algorithms.