No abstract

During the last decade, significant change of direction in the development of control theory and its application has attracted great attention from the academic and industrial communities. The concept of "Intelligent supervision "has been suggested as an alternative approach to conventional supervision techniques for complex control systems. The objective is to introduce new mechanisms permitting a more flexible supervision system, but especially more robust one, able to deal with model uncertainties and parameter variations. In this work, we present an application of the fuzzy approach in fault detection and isolation of surge in this compression system. This paper illustrates an alternative implementation to the compression systems supervision task using the basic principles of model-based fault detection and isolation associated with fuzzy modelling approach. Application results of a fault detection and isolation for a compression system are provided, which illustrate the relevance of the proposed fuzzy fault detection and isolation method.

Problem statement:The surge phenomenon in the centrifugal compressor, the nonlinearities and uncertainties of the compression system make it impossible to use a conventional controller over a wide range of operation. Approach: A new dual fuzzy controller for nonlinear model of compression system was proposed in this study. This fuzzy controller was designed that consisted of active surge control and phase control without any explicit system models, but driven in human thinking mechanism. Results: Simulation example of compression system was given to demonstrate the validity of proposed control scheme. It was shown that fuzzy controller can be simplified and good tracking control performance can be achieved by choosing appropriate fuzzy roles. But, the dual fuzzy controller can successfully intervene in control surge of compression system. Conclusion: This new fuzzy control methodology suggested in this study reproduced well main characteristics of turbo compressor dynamic model developed by Moore and Gretzer and give place to a more precise and easy to handle representation. It is about an inaccuracies reproducing with a certain degree of satisfaction of real process without being as much complex.

Abstract-This paper provides the possible application of the fuzzy approaches in fault detection and isolation area for a class of complex industrial processes with uncertain interval parameters. The main idea of fuzzy fault detection and isolation is to build a model of a diagnosis procedures, using rules-based Fuzzy Expert System, capable to minimize false alarms enhance detectability and isolability and minimize detection time by hardware implementation to improve reliability, safety and global efficiency. This paper illustrates an alternative implementation to the compression systems supervision task using the basic principles of model-based fault detection and isolation associated with the self-tuning of surge measurements with subsequent appropriate corrective actions. Using a combination of fuzzy modeling approach makes it possible to devise a fault-isolation scheme based on the given incidence matrix. Simulation results of a fault detection and isolation for a compression system are provided, which illustrate the relevance of the proposed FDI method.

Fuzzy control is a practical alternative for a variety of challenging control applications since it provides a convenient method for constructing nonlinear controllers via the use of heuristic information. This approach provides a formal methodology for representing, manipulating, and implementing a human's heuristic knowledge about how to modeled and to control a system. This paper focuses on the application of fuzzy control approach to the surge phenomena in centrifugal compression system. Fuzzy controller is designed to consist of an active surge control and phase control without any explicit system models, but driven in the human thinking mechanism. This fuzzy control methodology suggested in this work reproduced well the main characteristics of the turbo compressor dynamic model developed by Moore and Gretzer and give place to a more precise and easy to handle representation. Application and simulation results are performed to demonstrate the effectiveness of this controller. Studies show that, the proposed controller provides good tracking control performance for the compression system at different operating conditions and moreover improves the dynamic performances of the system.