Adaptive fuzzy modulation for networked PI control systems.

摘要

Networks and their applications have been evolving substantially in the last two decades. Network-based control systems, also called Networked Control Systems (NCS), are one of the hottest topics in network-based applications. By networked control system we mean controlling the system through the network, i.e., using networks for remote control and automation.; One major concern of using networks in remote control and automation is the Quality of Service (QoS) deterioration effects. These QoS deterioration effects such as: network-induced time delays, bandwidth constraints, multiple-packet transmission, and dropping network packets are serious tribulations. Without considering the effect of the QoS deterioration the performance of the NCS closed-loop control system could be degraded and even destabilized.; In this thesis, an adaptive fuzzy logic modulation scheme is proposed to compensate for the network-induced time delays in the network-based PI control systems. This scheme is based on modulating the control signal provided by the PI controller and applied to the remote controller via the network. A network-based controlled DC motor is used in this thesis to illustrate the effectiveness of the proposed scheme.