References of "Borguet, Sébastien"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailA way to deal with model-plant mismatch for a reliable diagnosis in transient operation
Borguet, Sébastien ULg; Dewallef, Pierre ULg; Léonard, Olivier ULg

in Journal of Engineering for Gas Turbines & Power (2008), 130(3),

Least-squares health parameter identification techniques, such as the Kalman filter, have been extensively used to solve diagnosis problems. Indeed, such methods give a good estimate provided that the ... [more ▼]

Least-squares health parameter identification techniques, such as the Kalman filter, have been extensively used to solve diagnosis problems. Indeed, such methods give a good estimate provided that the discrepancies between the model prediction and the measurements are Zero-mean, white, Gaussian random variables. In a turbine engine diagnosis, however this assumption does not always hold due to the presence of biases in the model. This is especially true for a transient operation. As a result, the estimated parameters tend to diverge from their actual values, which strongly degrades the diagnosis. The purpose of this contribution is to present a Kalman filter diagnosis tool where the model biases are treated as an additional random measurement error. The new methodology is tested on simulated transient data representative of a current turbofan engine configuration. While relatively simple to implement, the newly developed diagnosis tool exhibits a much better accuracy than the original Kalman filter in the presence of model biases. [less ▲]

Detailed reference viewed: 40 (9 ULg)
Full Text
Peer Reviewed
See detailThe Fisher Information Matrix as a Relevant Tool for Sensor Selection in Engine Health Monitoring
Borguet, Sébastien ULg; Léonard, Olivier ULg

in International Journal of Rotating Machinery (2008), 2008

Engine health monitoring has been an area of intensive research for many years. Numerous methods have been developed with the goal of determining a faithful picture of the engine condition. On the other ... [more ▼]

Engine health monitoring has been an area of intensive research for many years. Numerous methods have been developed with the goal of determining a faithful picture of the engine condition. On the other hand, the issue of sensor selection allowing an efficient diagnosis has received less attention from the community. The present contribution revisits the problem of sensor selection for engine performance monitoring within the scope of information theory. To this end, a metric that integrates the essential elements of the sensor selection problem is defined from the Fisher information matrix. An example application consisting in a commercial turbofan engine illustrates the enhancement that can be expected from a wise selection of the sensor set. [less ▲]

Detailed reference viewed: 55 (4 ULg)
Full Text
See detailA Study on Observability and Sensor Selection for Efficient Jet Engine Health Monitoring
Borguet, Sébastien ULg; Léonard, Olivier ULg

in Proceedings of ISROMAC-12 (2008, February)

Detailed reference viewed: 25 (3 ULg)
Full Text
See detailComparison of Adaptive Filtering Schemes for Gas Turbine Performance Diagnostics
Borguet, Sébastien ULg; Léonard, Olivier ULg

in Proceedings of the 4th International Conference on Advanced Computational Methods in Engineering (2008)

Kalman filters are widely used in the turbine engine community for health monitoring purpose. This algorithm has proven its capability to track gradual deterioration with a good accuracy. On the other ... [more ▼]

Kalman filters are widely used in the turbine engine community for health monitoring purpose. This algorithm has proven its capability to track gradual deterioration with a good accuracy. On the other hand, its response to rapid deterioration is either a long delay in recognising the fault, and/or a spread of the estimated fault on several components. The main reason of this deficiency lies in the transition model of the parameters that assumes a smooth evolution of the engine condition. The aim of this contribution is to compare two adaptive diagnosis tools that combine a Kalman filter and a secondary system that monitors the residuals. This auxiliary component implements on one hand a covariance matching scheme and on the other hand a generalised likelihood ratio test to improve the behaviour of the diagnosis tool with respect to abrupt faults. [less ▲]

Detailed reference viewed: 35 (4 ULg)
Full Text
Peer Reviewed
See detailA sensor-fault-tolerant diagnosis tool based on a quadratic programming approach
Borguet, Sébastien ULg; Léonard, Olivier ULg

in Journal of Engineering for Gas Turbines & Power (2008), 130(2),

Kalman filters are widely used in the turbine engine community for health monitoring purpose. This algorithm gives a good estimate of the engine condition provided that the discrepancies between the model ... [more ▼]

Kalman filters are widely used in the turbine engine community for health monitoring purpose. This algorithm gives a good estimate of the engine condition provided that the discrepancies between the model prediction and the measurements are Zero-mean, white random variables. However this assumption is not verified when instrumentation (sensor) faults occur As a result, the identified health parameters tend to diverge from their actual values, which strongly deteriorates the diagnosis. The purpose of this contribution is to blend robustness against sensor faults into a tool for performance monitoring of jet engines. To this end, a robust estimation approach is considered and a sensor-fault detection and isolation module is derived. It relies on a quadratic program to estimate the sensor faults and is integrated easily with the original diagnosis tool. The improvements brought by this robust estimation approach are highlighted through a series of typical test cases that may be encountered on current turbine engines. [less ▲]

Detailed reference viewed: 29 (9 ULg)
Full Text
Peer Reviewed
See detailCoupling Principle Component Analysis and Kalman Filtering Algorithms for On-Line Aircraft Engine Diagnostics
Borguet, Sébastien ULg; Léonard, Olivier ULg

in Proceedings of the 18th ISABE Conference (2007, September)

Engine health monitoring has been an area of intensive research for more than three decades. Numerous methods have been developed with the goal of determining a faithful picture of the engine condition ... [more ▼]

Engine health monitoring has been an area of intensive research for more than three decades. Numerous methods have been developed with the goal of determining a faithful picture of the engine condition. It becomes largely admitted that a practical implementation of a monitoring tool will rely on an adequate fusion of some techniques. In this framework, the present contribution proposes an original approach for coupling two diagnosis tools in order to enhance the capability of an engine health monitoring system. One tool is based on a Principal Component Analysis scheme and the other one on a Kalman filter technique. The three methodologies are compared and the benefit of the fused tool is demonstrated on simulated fault cases which can be expected on a current turbofan layout. [less ▲]

Detailed reference viewed: 40 (3 ULg)
Full Text
Peer Reviewed
See detailOn Inverse Problems in Turbine Engine Parameter Estimation
Henriksson, Mattias; Borguet, Sébastien ULg; Léonard, Olivier ULg et al

in Proceedings of the ASME Turbo Expo 2007 (2007, May)

This paper extends previous work on model order reduction based on singular value decomposition. It is shown how the decrease in estimator variance must be balanced against the bias on the estimate ... [more ▼]

This paper extends previous work on model order reduction based on singular value decomposition. It is shown how the decrease in estimator variance must be balanced against the bias on the estimate inevitably introduced by solving the inverse problem in a reduced order space. A proof for the decrease in estimator variance by means of multi-point analysis is provided. The proof relies on comparing the Cramer-Rao lower bound of the single point and the multi-point estimators. Model order selection is discussed in the presence of a varying degree of a priori parameter information, through the use of a regularization parameter. Simulation results on the SR-30 turbojet engine indicate that the theoretically attainable multi-point improvements are difficult to realize in practical jet engine applications. [less ▲]

Detailed reference viewed: 41 (3 ULg)
Full Text
Peer Reviewed
See detailA Sensor-Fault-Tolerant Diagnosis Tool Based on a Quadratic Programming Approach
Borguet, Sébastien ULg; Léonard, Olivier ULg

in Proceedings of the ASME Turbo Expo 2007 (2007, May)

Kalman filters are widely used in the turbine engine community for health monitoring purpose. This algorithm gives a good estimate of the engine condition provided that the discrepancies between the model ... [more ▼]

Kalman filters are widely used in the turbine engine community for health monitoring purpose. This algorithm gives a good estimate of the engine condition provided that the discrepancies between the model prediction and the measurements are zeromean, white random variables. However, this assumption is not verified when instrumentation (sensor) faults occur. As a result, the identified health parameters tend to diverge from their actual values which strongly deteriorates the diagnosis. The purpose of this contribution is to blend robustness against sensor faults into a tool for performance monitoring of jet engines. To this end, a robust estimation approach is considered and a Sensor Fault Detection and Isolation module is derived. It relies on a quadratic program to estimate the sensor faults and is integrated easily with the original diagnosis tool. The improvements brought by this robust estimation approach are highlighted through a series of typical test-cases that may be encountered on current turbine engines. [less ▲]

Detailed reference viewed: 22 (0 ULg)
Full Text
Peer Reviewed
See detailA Quadratic Programming Framework for Constrained and Robust Jet Engine Health Monitiring
Borguet, Sébastien ULg; Léonard, Olivier ULg

in Proceedings of the 2nd European Conference on Aerospace Sciences (2007)

Kalman filters are largely used in the jet engine community for condition monitoring purpose. This algorithm gives a good estimate of the engine condition provided that the residuals between the model ... [more ▼]

Kalman filters are largely used in the jet engine community for condition monitoring purpose. This algorithm gives a good estimate of the engine condition provided that the residuals between the model prediction and the measurements are zero-mean, Gaussian random variables. In the case of sensor faults, this assumption does not hold anymore and consequently the diagnosis is spoiled. This contribution presents a recursive estimation algorithm based on a Quadratic Programming formulation which provides robustness against sensor faults and allows constraints on the health parameters to be specified. The improvements in estimation accuracy brought by this new algorithm are illustrated by a series of typical test-cases that may be encountered on current turbofan engines. [less ▲]

Detailed reference viewed: 10 (2 ULg)
Full Text
Peer Reviewed
See detailA Way to Deal with Model-Plant Mismatch for a Reliable Diagnosis in Transient Operation
Borguet, Sébastien ULg; Dewallef, Pierre ULg; Léonard, Olivier ULg

in Proceedings of the ASME Turbo Expo 2006 (2006, May)

Least-squares health parameter identification techniques such as the Kalman filter have been massively used to solve the problem of turbine engine diagnosis. Indeed, such methods give a good estimate ... [more ▼]

Least-squares health parameter identification techniques such as the Kalman filter have been massively used to solve the problem of turbine engine diagnosis. Indeed, such methods give a good estimate provided that the discrepancies between the model prediction and the measurements are zero-mean, white random variables. In turbine engine diagnosis, however, this assumption does not always hold due to the presence of biases in the model. This is especially true for transient operation. As a result, the estimated parameters tend to diverge from their actual values which strongly deteriorates the diagnosis. The purpose of this contribution is to present a Kalman filter diagnosis tool where the model biases are treated as an additional random measurement error. The new methodology is tested on simulated transient data representative of a current turbofan layout. While relatively simple to implement, the newly developed diagnosis tool exhibits a much better accuracy than the original Kalman filter in the presence of model biases. [less ▲]

Detailed reference viewed: 26 (2 ULg)
Full Text
See detailCycle Optimization of a Turbine Engine: an Approach Based on Genetic Algorithms
Borguet, Sébastien ULg; Kelner, Vincent ULg; Léonard, Olivier ULg

in Proceedings od the 7th Belgian Congress on Theoretical and Applied Mechanics (2006, May)

Multi-objective optimization is performed of a turbofan. The objectives are to minimize the Specific Fuel Consumption at cruise conditions, as well as to maximize the Specific Thrust during the take-off ... [more ▼]

Multi-objective optimization is performed of a turbofan. The objectives are to minimize the Specific Fuel Consumption at cruise conditions, as well as to maximize the Specific Thrust during the take-off phase. Three design variables have been selected: the by-pass ratio, the fan pressure ratio, and the high pressure compressor pressure ratio. The backbones of the optimization approach consist of a genetic algorithm and a modular gas turbine simulation tool. [less ▲]

Detailed reference viewed: 34 (3 ULg)
Full Text
Peer Reviewed
See detailOn-Line Transient Engine Diagnostics in a Kalman Filtering Framework
Borguet, Sébastien ULg; Dewallef, Pierre ULg; Léonard, Olivier ULg

in Proceedings of the ASME Turbo Expo 2005 (2005, June)

A common assumption made in the performance assessment of a turbine engine for aircraft propulsion consists in restricting the data processing to steady-state data. This especially holds for on-board ... [more ▼]

A common assumption made in the performance assessment of a turbine engine for aircraft propulsion consists in restricting the data processing to steady-state data. This especially holds for on-board performance monitoring of a commercial aircraft which spends up to 90% of the time in cruise flight where such conditions are satisfied. The present contribution is intended to investigate the ability of a diagnosis method to process unsteady data rather than steady-state data. The aim of this unsteady approach is to strongly reduce the time and the efforts spent to obtain a reliable diagnosis. In order to assess the improvements in terms of diagnosis efficiency and engine operability, the resulting diagnostic method is tested for different degradations that can be expected on commercial turbofans. The results are also compared to those obtained from cruise flight steady-state data in order to balance the two approaches. [less ▲]

Detailed reference viewed: 34 (7 ULg)
See detailVers un contrôle adaptatif des turboréacteurs
Borguet, Sébastien ULg

Master of advanced studies dissertation (2004)

Detailed reference viewed: 25 (9 ULg)