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Fault Detection for Common Rail Diesel Engines with Low and High Pressure Exhaust Gas Recirculation

Inst. of Automatic Control, TU Darmstadt-Christopher Eck, Andreas Sidorow, Ulrich Konigorski, Rolf Isermann
Published 2011-09-11 by SAE International in United States
The complexity of the air path of modern common rail diesel engines is rapidly increasing and simultaneously, the demand on air and turbocharger control performances is becoming more challenging. To meet the upcoming emission regulations, the usage of a low pressure exhaust gas recirculation (EGR) circuit in addition to the standard high pressure EGR circuit is often considered. This kind of architecture usually requires a more sophisticated air control system in which a precise control of the EGR flow delivered by the two recirculation branches is required. Moreover, as an alternative or in addition to the low pressure EGR, the implementation of a NOx reduction system e.g. a NOx trap is possible. To proper maintain the correct efficiency of this kind of after-treatment system, special regeneration strategies are adopted where a rich combustion is used instead of the standard Diesel lean mode. During the rich phase the air control plays a key role since the air charge delivered to the cylinders is directly related to the torque. The above example shows that an air system…
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Model Based Fault Diagnosis of the Intake and Exhaust Path of Turbocharged Diesel Engines

TU Darmstadt-Andreas Sidorow, Christopher Eck, Rolf Isermann, Ulrich Konigorski
Published 2011-09-11 by SAE International in United States
Faults in the intake and exhaust path of turbocharged common-rail Diesel engines can lead to an increase of emissions and performance losses. Standard fault detection strategies based on plausibility checks and trend checking of sensor data are not able to detect and isolate all faults appearing in the intake and exhaust path without employing additional sensors. By applying model based methods a limited sensor configuration can be used for fault detection. Therefore a model based fault diagnosis concept with parity equations is considered, [1]. In this contribution the fault diagnosis system, which comprises semi-physical thermodynamic turbocharger model, models of gas pressure in the intake and exhaust manifold, residual generation, residual to symptom transformation and fault diagnosis is presented.The residuals are calculated from the difference between the virtual sensors and the measured values and from the difference between the virtual sensors and outputs of reference models which represent the turbocharger quantities in the fault-free operation, [1], [2]. The created residuals are applied for the detection of leakages, restrictions and clogged actuators in the intake and exhaust…
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Model Based Fault Detection of the Air and Exhaust Path of Diesel Engines Including Turbocharger Models

GM Powertrain Europe-Francesco Cianflone , Gerhard Landsmann
Inst. of Automatic Control, TU Darmstadt-Andreas Sidorow, Rolf Isermann
Published 2011-04-12 by SAE International in United States
Faults in the intake and exhaust path of turbocharged common-rail diesel engines lead to an increase of emissions and to performance losses. Fault detection strategies based on plausibility checks, threshold based trend or limit checking of sensor data are not able to detect and isolate all faults appearing in the intake and exhaust path without increasing of the number of sensors. The need to minimize mass and reduce cost, including the number of sensors, while maintaining robust performance leads to higher application of models for intake and exhaust path components. Therefore a concept of model based fault detection with parity equations is considered. It contains the following parts: modeling, residual generation with parity equations using parallel nonlinear models, fault to symptom transformation with masking of residuals dependent on the operating point and limit violation checking of the residuals.A semi-physical, isentropic efficiency based model of the turbocharger with variable geometry (VGT) can help to detect more faults and to extend the operation region of the fault detection. The developed semi-physical turbocharger model contains a physical core…
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Parameter Estimation for Physical Based Air Path Models of Turbocharged Diesel Engines — An Experience Based Guidance

SAE International Journal of Engines

Institute of Automatic Control, TU Darmstadt, Germany-Matthias Mrosek, Sebastian Zahn, Rolf Isermann
  • Journal Article
  • 2009-24-0134
Published 2009-09-13 by Consiglio Nazionale delle Ricerche in Italy
Physical based air path models lead to a substructuring of the highly complex engine systems into several interacting submodels of low order. They offer detailed process information, support advanced control system design and allow to significantly reduce the calibration effort. Hence, physical approaches are predestinated to cope with the rise in system complexity and with the increasingly challenging demands concerning air system performance. Whereas the basic model equations are known a general methodology to obtain the model parameters is lacking. The purpose of this paper is to shed light on the identification procedure and to offer the automotive engineer helpful advice to gain well calibrated simulation models. Analysing the air path equations the determining factors on the parameter quality are investigated. Based on the results sensible modifications of the test bed setup and the measurement strategy are presented. In addition the need for careful data processing is discussed. The comparison of simulation results and measurement data from the engine test bed proves the potential of the developed methodology.
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A Rule-based Collision Avoidance System – Scene Interpretation, Strategy Selection, Path Planning and System Intervention

SAE International Journal of Passenger Cars - Mechanical Systems

Adam Opel GmbH-Ali Khanafer, Dirk Balzer
TU Darmstadt-Rolf Isermann
  • Journal Article
  • 2009-01-0156
Published 2009-04-20 by SAE International in United States
To reduce accidents and fatalities on the roads, active safety systems which can avoid accidents or mitigate their effects are increasingly required. Contrary to already available driver assistance systems a future system can be a Collision Avoidance System which will be able to solve many critical traffic situations by warning, braking or steering. This paper will present a system consisting of environment sensing and situation analysis blocks as well as intervening strategy blocks. The main focus will be put on the scene interpretation of a situation and its optimization. Therefore a rule-based Fuzzy System will be described. Furthermore the Strategy Selection and the Path Planning in case of system intervention will be shown by simulation.The system has been developed during the work at the Adam Opel GmbH.
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Model-Based Fault Detection for An Active Vehicle Suspension

DaimlerChrysler Research Center Frankfurt-Hans-Peter Schöner
Darmstadt University of Technology-Daniel Fischer, Rolf Isermann
  • Technical Paper
  • 2004-05-0054
Published 2004-05-23 by Society of Automotive Engineers of Korea in South Korea
Automobiles show an increasing number of mechatronic developments by the integration of mechanic and electronic systems. In the case of vehicle suspension systems, this comprises the application of hydraulic, pneumatic and/or electric actuators with the aim of active roll and pitch stabilization and an increase of driving safety and comfort in general. Supplementary, the integration of these actuators and the involved sensors and electronic control units enables a detailed process supervision, fault detection and identification (FDI) for the whole system. This was developed for an active vehicle suspension system on a test rig.The inquired active suspension is a hydraulic fully loaded active suspension, whereat a hydraulic plunger is added in series with the conventional steel spring. This assembly is equivalent to the Active- Body-Control System of DaimlerChrysler. The test rig is equipped with suitable sensors for a series passenger car. The goal is to detect faults of all involved sensors with the distinction of noise, outliers, breakdown, and also offset and gain faults.One approach to solve FDI problems is to use parameter estimation and parity…

Fault-Tolerant Filtering in Active Vehicle Suspensions

DaimlerChrysler Research Center-Eberhard Kaus
Darmstadt University of Technology-Daniel Fischer, Rolf Isermann
  • Technical Paper
  • 2004-05-0180
Published 2004-05-23 by Society of Automotive Engineers of Korea in South Korea
The problem considered in this paper is the design and analysis of a sensor fault-tolerant filtering method for active vehicle suspensions. As the suspension system of an automotive vehicle influences driving comfort and safety, a reliable operation of the system is required.Components, sensors and actuators in physical systems are often subject to unexpected and not permitted deviations from acceptable/usual/standard conditions. These deviations are called faults. Faults can cause the loss of the overall performance of a physical system, which may present hazards to personnel or lead to unacceptable economic loss. The aim of the fault-tolerant control is to adjust or to modify on-line the nominal control laws in order to maintain the safety of the operators and the reliability of the process.This paper aims at investigating the design of a sensor fault- tolerant filtering method mainly because: (1) sensors are critical components in almost all modern engineering system; (2) a sensor fault- tolerant filter can, in principle, indirectly solve the problem of sensor fault-tolerant control. In fact, from the control point of view, sensor fault-tolerant…

Controller Design for An Active Steering System in Passenger Cars Based on Local Linear Models

Darmstadt University of Technology-Jürgen Schmitt, Matthias Schorn, Rolf Isermann
  • Technical Paper
  • 2004-05-0046
Published 2004-05-23 by Society of Automotive Engineers of Korea in South Korea
A new approach for an active steering control system based on local linear models to improve the lateral dynamic behavior of passenger cars is considered. In combination with braking control systems the active steering system is used to stabilize the vehicle in critical situations.Similar to the Electronic Stability Program (ESP) which uses active braking, the active steering system compares the desired yaw rate calculated from the steering wheel angle with the actual yaw rate. To calculate the desired yaw rate a time-variant one track model is used for a dry road surface. A feedback controller is designed to control the desired yaw rate given by the driver by generating an additional steering wheel angle. The used one track model depends on the vehicle velocity, on front and rear cornering stiffness, on the vehicle mass and on the moment of inertia. Furthermore, dynamic vertical load variation, large tire side slip angles and the influence of roll and pitch motions result in deviations of the one track model. However, the vehicle velocity can be measured and its…

Improving the Performance of an Active Steering System by Variation of the Antiroll Bar Stiffness at the Front and Rear Axle

TU Darmstadt-Jürgen Schmitt, Matthias Schorn, Rolf Isermann
  • Technical Paper
  • 2004-35-0053
Published 2004-04-19 by University of Salerno in Italy
This paper proposes a control system for active steering of a passenger car based on Local Linear Models. Furthermore, it is investigated how an active suspension system can improve the performance of the active steering system in critical driving situations. Active antiroll bars at the front and rear axle are introduced as active elements in the suspension system. Based on the characteristic velocity of the vehicle, a control concept for the antiroll bar stiffness variation at the front and rear axle is proposed. Simulations with a three-dimensional vehicle model are carried out to verify the effectiveness of the proposed control system.

Characteristic Velocity Stability Indicator for Passenger Cars

Darmstadt University of Technology-Rolf Isermann, Marcus Börner
  • Technical Paper
  • 2004-35-0133
Published 2004-04-19 by University of Salerno in Italy
A precise knowledge about the current driving condition is getting increasingly important for future driver assistance systems to support the prevention of any critical driving situation. Moreover a precise knowledge about the driving situation can be used in testing and comparing new passenger cars. After a short introduction of a lateral vehicle model, an analytical approach for an online calculation of different driving conditions (i.e., stability, understeering, oversteering, and neutralsteering) is given. A characteristic velocity stability indicator is defined, which allows online computation of the present driving condition. Real test drives show the application.