Fault detection and isolation

A. Genovesi, J. Harmand, and J.P. Steyer. Integrated fault detection and isolation Application to a winery s wastewater treatment plant. Applied Intelligence Journal (APIN), 13 207-224, 2000. 

J.P. Steyer, A. Genovesi, and J. Harmand. Advanced monitoring and control of anaerobic wastewater treatment plants Fault detection and isolation. Wat. Sci. TechnoL, 43(7) 183-190, 2001. 

The models used can be either fixed or adaptive and parametric or non-parametric models. These methods have different performances depending on the kind of fault to be treated i.e., additive or multiplicative faults). Analytical model-based approaches require knowledge to be expressed in terms of input-output models or first principles quantitative models based on mass and energy balance equations. These methodologies give a consistent base to perform fault detection and isolation. The cost of these advantages relies on the modeling and computational efforts and on the restriction that one places on the class of acceptable models. 

Related to fault detection and isolation Cred credibility function... 

The literature focused on model-based FD presents a few applications of observers to chemical plants. In [10] an unknown input observer is adopted for a CSTR, while in [7] and [21] an Extended Kalman Filter is used in [9] and [28] Extended Kalman Filters are used for a distillation column and a CSTR, respectively in [45] a generalized Luenberger observer is presented in [24] a geometric approach for a class of nonlinear systems is presented and applied to a polymerization process in [38] a robust observer is used for sensor faults detection and isolation in chemical batch reactors, while in [37] the robust approach is compared with an adaptive observer for actuator fault diagnosis. 

In order to achieve both sensor fault detection and isolation, two state observers of the system are adopted the first observer uses the measurements provided by Sr, 1 and 5j i, while the second observer uses the measurements provided by Sr> 2 and 6 2-... 

The healthy measure, obtained via the diagnostic system described above, is used to feed a bank of observers providing process/actuator fault detection and isolation. One observer detects the occurrence of an actuator or process fault, while the other Np observers, each one corresponding to a fault type, are used for isolation and identification. 

Fig. 6.6 Sensor fault detection and isolation residuals (slow drift at sensor k = 9000 s)...

Figures 6.9 and 6.10 show the results obtained when the measured signal of sensor Spi has been frozen at its value taken at /[ = 3000 s. Since these last two cases involve abrupt faults, detection and isolation are practically contemporary.

Fig. 6.20 Sensor Sr 2 and cooling system faults detection and isolation residuals for the sensor fault...

K. Patan and T. Parisini. Identification of neural dynamic models for fault detection and isolation the case of a real sugar evaporation process. Journal of Process Control, 15 67-79, 2005. 

Keywords sensor network, genetic algorithm, fault detection and isolation. 

Fault detection and isolation based on the model-based approach ... 

In this paper, we present a method for the fault detection and isolation based on the residual generation. The main idea is to reconstruct the outputs of the system from the measurement using the extended Kalman filter. The estimations are compared to the values of the reference model and so, deviations are interpreted as possible faults. The reference model is simulated by the dynamic hybrid simulator, PrODHyS. The use of this method is illustrated through an application in the field of chemical process. 

Keywords Fault Detection and Isolation, Extended Kalman Filter, Dynamic Hybrid Simulation, Object Differential Petri nets. Distance. 

In a very competitive economic context, the reliability of the production systems can be a decisive advantage. This is why, the fault detection and diagnosis are the purpose of a particular attention in the scientific and industrial community. The major idea is that the defect must not be undergone but must be controlled. Nowadays, these functions remain a large research field. The literature quotes as many fault detection and diagnosis methods as many domains of application (Venkatasubramanian, et ah, 2003). A notable number of works has been devoted to fault detection and isolation, and the techniques are generally classified as ... 

In this paper, the proposed approach to fault detection and isolation is a model-based approach. The first part of this communication focuses on the main fundamental concepts of the simulation library PrODHyS, which allows the simulation of the system reference model of a typical process example. Then, the proposed detection approach is presented. This exploits the extended Kalman Filter, in order to generate a fault indicator. In the last part, this approach is exploited through the simulation of the monitoring of a didactic example. 

Fault Detection and Isolation Based on the Model-Based Approach... 

Fault detection and isolation are a prerequisite of fault diagnosis necessitating system observability and proper signal measurement and processing in the presence of noise. The thus obtained information then is to be processed in real time by a decision support software system that takes into account that sensors themselves can be faulty. According to Venkatasubramanian et al. [14-16], fault detection and diagnosis methods may be classified into... 

Patton, R., Chen, J. (1997). Observer-based fault detection and isolation Robustness and applications. Control Engineering Practice, 5,671-682. 

Staroswiecki, M., Comtet-Varga, G. (2001). Analytictil redundancy relations for fault detection and isolation in algebraic dynamic systems. Automatica. 37.687-699. 

Zhang, X. (2009). Modeling, control, fault detection and isolation of chemical processes using a bond graph framework [PhD thesis], Texas Tech University. 

Moreover, as to hybrid system models, the previously considered examples show that fault detectability and isolability is mode dependent. As can be seen from the FSM in Table4.2, faults in some components may be detectable in all modes, e.g. a faulty capacitance in the switched network of Fig. 3.4, while other faults can only be detected in some modes, such as faulty resistances R and R2. (Wang et al. call such faults weakly detectable [9].) It may also be possible that a fault cannot be detected in none of the system modes. Similar observations can be made with regard to fault isolation bearing in mind that a necessary condition for a fault to be isolated is that it can be detected. 

Samantaray, A. K., Medjaher, K., Quid Bouamama, B., Staroswiecki, M., Dauphin-Tanguy, G. (2006). Diagnostic bond graphs for online fault detection and isolation. Simulation Modelling Practice and Theory, 14 3), 237-262. 

Quid Bouamama, B., Medjaher, K., Bayart, M., Samantaray, A., Coniard, B. (2005). Fault detection and isolation of smart actuators using bond graphs and external models. Control Engineering Practice, 13(2), 159-175. 

Borutzky, W. (2012). Bond-graph-based fault detection and isolation for hybrid system models. Proceedings of IMechE Part I J Systems and Control Engineering, 226(6), 742-760. 

Meinguet, R, Sandulescu, P., Asltm, B., Lu, L., Ngac-Ky, N., Kestelyn, X., et al. (2012). A signal-based technique for fault detection and isolation of inverter faults in multi-phase drives. In IEEE International Conference On Power Electronics, Drives and Energy Systems 2012 (PEDES 2012). (pp. 1-6). Bengaluru, India. 

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