الفهرس | Only 14 pages are availabe for public view |
Abstract Integration of a communication network in the control system loops makes the analysis and the design of the networked control systems (NCSs) more complex. Hence, the controlling of systems over the network leads to some challenges or problems include networked-induced delays and data packet losses which can deteriorate the system performance and may destabilize the system. In this thesis, a robust 𝐻∞ adaptive fuzzy controller (AFC), a robust adaptive fuzzy predictive controller (AFPC) and a remote adaptive predictive fuzzy proportional-derivative (RAPF-PD) controller have been presented to act as solutions to some of these challenges in NCSs. Furthermore, the proposed schemes improve the performance of the system in the presence of networked-induced delays, some packet losses, external disturbances, and structure uncertainty with guarantee the stability of the NCSs. The proposed 𝐻∞ AFC is applied for a class of nonlinear systems over network in the forward channel. The fuzzy logic systems (FLSs) are used as universal approximators to approximate the unknown nonlinear function of the system. The proposed 𝐻∞ AFC has a filtered tracking error to facilitate the handling of the networkedinduced delay and also it is robust enough to cope the external disturbances and the effect of the fuzzy approximation error which causes the modeling errors. The AFPC based on adaptive smith predictor (ASP) and state predictor has been developed for a class of nonlinear systems over network in the forward and feedback communication channels. The ASP is employed to compensate the time-varying delays effect to achieve the desired tracking performance. In addition to the RAPF-PD controller based on ASP has been developed for networked direct current motor position control via a real-time communication between two personal computers using user datagram protocol (UDP). Finally, simulated applications have demonstrated the feasibility, effectiveness and robustness of the proposed schemes. |