liu.seSearch for publications in DiVA
Change search
Refine search result
1234 1 - 50 of 183
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the 'Create feeds' function.
  • 1.
    Alegret, Guillem
    et al.
    MAN Diesel & Turbo, Copenhagen, Denmark.
    Llamas, Xavier
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Vejlgaard-Laursen, Morten
    MAN Diesel & Turbo, Copenhagen, Denmark.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Modeling of a Large Marine Two-Stroke Diesel Engine with Cylinder Bypass Valve and EGR System2015In: 10th IFAC Conference on Manoeuvring and Control of Marine Craft, International Federation of Automatic Control (IFAC) , 2015, Vol. 48, 273-278 p.Conference paper (Refereed)
    Abstract [en]

    A nonlinear mean value engine model (MVEM) of a two-stroke turbocharged marine diesel engine is developed, parameterized and validated against measurement data. The goal is to have a computationally fast and accurate engine model that captures the main dynamics and can be used in the development of control systems for the newly introduced EGR system. The tuning procedure used is explained, and the result is a six-state MVEM with seven control inputs that capture the main system dynamics.

  • 2.
    Alegret, Guillem
    et al.
    MAN Diesel & Turbo, Copenhagen, Denmark.
    Llamas, Xavier
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Vejlgaard-Laursen, Morten
    MAN Diesel & Turbo, Copenhagen, Denmark.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Modeling of a Large Marine Two-Stroke Diesel Engine with Cylinder Bypass Valve and EGR System2015In: 10th IFAC Conference on Manoeuvring and Control of Marine Craft MCMC 2015: Copenhagen, 24–26 August 2015 / [ed] Roberto Galeazzi and Mogens Blanke, IFAC Papers Online, 2015, Vol. 48, 273-278 p.Conference paper (Refereed)
    Abstract [en]

    A nonlinear mean value engine model (MVEM) of a two-stroke turbocharged marine diesel engine is developed, parameterized and validated against measurement data. The goal is to have a computationally fast and accurate engine model that captures the main dynamics and can be used in the development of control systems for the newly introduced EGR system. The tuning procedure used is explained, and the result is a six-state MVEM with seven control inputs that capture the main system dynamics.

  • 3.
    Andersson, Ingemar
    et al.
    Chalmers.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering.
    A Parametric Model for Ionization Current in a Four Stroke SI Engine2009In: JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND CONTROL-TRANSACTIONS OF THE ASME, ISSN 0022-0434, Vol. 131, no 2, 021001- p.Article in journal (Refereed)
    Abstract [en]

    A model for the thermal part of an ionization signal is presented that connects the ionization current to cylinder pressure and temperature in a spark ignited internal combustion engine. One strength of the model is that, after calibration, it has only two free parameters: burn angle and initial kernel temperature. By fitting the model to a measured ionization signal, it is possible to estimate both cylinder pressure and temperature, where the pressure is estimated with good accuracy. The model approach is validated on engine data. Cylinder pressure and ionization current data were collected on a Saab four-cylinder spark ignited engine for a variation in ignition timing and air-fuel ratio. The main result is that the parametrized ionization current model can be used to estimating combustion properties as pressure, temperature, and content of nitric oxides based on measured ionization currents. The current status of the model is suitable for off-line analysis of ionization currents and cylinder pressure. This ionization current model not only describes the connection between the ionization current and the combustion process, but also offers new possibilities for engine management system to control the internal combustion engine.

  • 4.
    Andersson, Ingemar
    et al.
    Chalmers.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Ion Current Interpretation for Sensing and Control of Combustion Stability1999In: Second conference on Computer Science and Systems Engineering in Linköping, 1999, 119-124 p.Conference paper (Refereed)
  • 5.
    Andersson, Ingemar
    et al.
    Chalmers.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Ion Sensing for Combustion Stability Control of a Spark Ignited Direct Injected Engine2000In: Electronic Engine Controls: Controls, 2000, Vol. SP-1500Conference paper (Refereed)
    Abstract [en]

    The combustion stability of a direct injected spark ignited engine depends on the injection timing and it is desirable to have a controller that minimizes the combustion variability. A novel approach for determining combustion stability in stratified mode is presented that rely on the ionization current and enables closed loop control of the injection timing. The coefficient of variation for IMEP is used as a measure of combustion stability and a connection between maximum torque and low combustion variability is pointed out. The coefficient of variation of the ion current integral is well correlated with the coefficient of variation for IMEP. Furthermore, it is shown how the integral of the ion current together with COV(ion integral) can be used to determine the combustion stability and to distinguish high combustion stability from misfire.

  • 6.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering.
    Air-to-Cylinder Observer on a Turbocharged SI-Engine with Wastegate2001Conference paper (Refereed)
    Abstract [en]

    Observers for air mass flow to the cylinder is studied on a turbocharged SI-engine with wastegate. A position change of the wastegate influences the residual gas mass and causes the volumetric efficiency to change, which produces a transient in the air mass flow to the cylinder. Two standard methods of estimating air-to-cylinder are investigated. A new nonlinear air-to-cylinder observer is suggested with two states: one for intake manifold pressure and one for the offset in in-cylinder air mass compared to expected through the volumetric efficiency. The observers are validated on intake manifold pressure data from a turbocharged spark ignited production engine with wastegate.

  • 7.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering.
    Cylinder Air Charge Estimator in Turbocharged SI-Engines2004Conference paper (Refereed)
  • 8.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering.
    Detection of Exhaust Manifold Leaks on a Turbocharged SI-engine with Wastegate2002Conference paper (Refereed)
  • 9.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering.
    Exhaust Manifold Pressure Estimation on a Turbocharged SI-engine with Wastegate2001Conference paper (Refereed)
  • 10.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering.
    Mean-value Observer for a Turbocharged SI-engine2004Conference paper (Refereed)
  • 11.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Observer Based Feedforward Air-Fuel Control of Turbocharged SI-Engines2005Conference paper (Refereed)
    Abstract [en]

    Abstract: Air-fuel control on turbocharged (TC) SI-engines require precise prediction of the cylinder air-charge (CAC). Using an observer it is possible to both estimate the necessary system states and to provide a framework to design the necessary CAC feedforward controller. Here a mean value engine model of a TC SI-engine is used to develop an observer. The output of the observer is fed as an initial condition to a predictor which is used for feedforward of the CAC for air-fuel control. The resulting controller is experimentally validated on a SAAB 2.0 dm^3 TC engine using tip-in and tip-out transients. The results show that the excursions in lambda are less than 5%.

  • 12.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Observer Based Feedforward Air-Fuel Control of Turbocharged SI-Engines2005In: Proceedings of 16th Triennial World Congress, Prague, Czech Republic, IFAC Papers Online, 2005, Vol. 38, 200-205 p.Conference paper (Refereed)
    Abstract [en]

    Air-fuel control on turbocharged (TC) SI-engines require precise prediction of the cylinder air-charge (CAC). Using an observer it is possible to both estimate the necessary system states and to provide a framework to design the necessary CAC feedforward controller. Here a mean value engine model of a TC SI-engine is used to develop an observer. The output of the observer is fed as an initial condition to a predictor which is used for feedforward of the CAC for air-fuel control. The resulting controller is experimentally validated on a SAAB 2.0 dm3 TC engine using tip-in and tip-out transients. The results show that the excursions in Λ are less than 5%

  • 13.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Three Way Catalyst Control using a PI-style Controller with HEGO Sensor Feedback2002Conference paper (Refereed)
    Abstract [en]

    Recent research has shown that control of the oxygen content in the catalyst has potential to further reduce the emissions from spark ignited engines. This gives rise to a cascade structure where an outer loop influences an inner loop. Different ways of augmenting the inner loop, a traditional PI-feedback controller based on feedback from the binary oxygen sensor, are studied. The SI-engine constraints on the control, such as low emissions and drive ability, are considered in the evaluation of the controllers. The result is that a delayed switching of the sensor is needed to control the oxygen content in the TWC using binary sensor feedback.

  • 14.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering.
    Three Way Catalyst Control using PI-style Controller with HEGO Sensor Feedback2002Conference paper (Refereed)
  • 15.
    Andersson, Per
    et al.
    Linköping University, Department of Electrical Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering.
    Modeling and Architecture Examples of Model Based Engine Control1999Conference paper (Refereed)
  • 16. Andersson, Per
    et al.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Modelling and Architecture Examples of Model Based Engine Control1999Conference paper (Refereed)
    Abstract [en]

    Environmental regulations and drivability issues are driving forces in the development of control systems for automotive engines. Precise control of the air and fuel is fundamental for achieving the goals. Furthermore, the architecture for the controller plays a central role in how the goals are achieved.

    A comparison is made between two conventional controller structures and a model based structure. The performance of the different control structures is evaluated on a simulation model. To point out the differences the evaluation is concentrated to transient conditions where a step in throttle angle is used as input to the system. In addition, connections between controllers and the engine model is discussed.

  • 17.
    Andersson, Per
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Frisk, Erik
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Eriksson, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Sensor Selection for Observer Feedback in Turbocharged Spark Ignited Engines2005Conference paper (Refereed)
  • 18.
    Bachmann, Bernhard
    et al.
    Dept. Mathematics and Engineering, University of Applied Sciences, Bielefeld, Germany.
    Ochel, Lennart
    Dept. Mathematics and Engineering, University of Applied Sciences, Bielefeld, Germany.
    Ruge, Vitalij
    Dept. Mathematics and Engineering, University of Applied Sciences, Bielefeld, Germany.
    Gebremedhin, Mahder
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory.
    Fritzson, Peter
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory.
    Nezhadali, Vaheed
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Sivertsson, Martin
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Parallel Multiple-Shooting and Collocation Optimization with OpenModelica2012In: Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany, Linköping University Electronic Press, 2012, 659-668 p., 067Conference paper (Refereed)
    Abstract [en]

    Nonlinear model predictive control (NMPC) has become increasingly important for today’s control engineers during the last decade. In order to apply NMPC a nonlinear optimal control problem (NOCP) must be solved which needs a high computational effort.

    State-of-the-art solution algorithms are based on multiple shooting or collocation algorithms; which are required to solve the underlying dynamic model formulation. This paper describes a general discretization scheme applied to the dynamic model description which can be further concretized to reproduce the mul-tiple shooting or collocation approach. Furthermore; this approach can be refined to represent a total collocation method in order to solve the underlying NOCP much more efficiently. Further speedup of optimization has been achieved by parallelizing the calculation of model specific parts (e.g. constraints; Jacobians; etc.) and is presented in the coming sections.

    The corresponding discretized optimization problem has been solved by the interior optimizer Ipopt. The proposed parallelized algorithms have been tested on different applications. As industrial relevant application an optimal control of a Diesel-Electric power train has been investigated. The modeling and problem description has been done in Optimica and Modelica. The simulation has been performed using OpenModelica. Speedup curves for parallel execution are presented.

  • 19.
    Broomhead, Timothy James
    et al.
    Department of Mechanical Engineering, The University of Melbourne, Australia.
    Manzie, Chris
    Department of Mechanical Engineering, The University of Melbourne, Australia.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Brear, Michael
    Department of Mechanical Engineering, The University of Melbourne, Australia.
    Hield, Peter
    Defence Science and Technology Organisation, Australia.
    A Robust Model Predictive Control Framework for Diesel Generators2014In: Proceedings of 19th IFAC World Congress / [ed] Edward Boje; Xiaohua Xia, International Federation of Automatic Control (IFAC) , 2014, Vol. 47, 11848-11853 p.Conference paper (Refereed)
    Abstract [en]

    A constraint tightened linear-time-varying MPC framework is proposed with applications in power tracking for variable and fixed speed generators. Current constraint tightening approaches are extended to allow for practical applications where future system representations are unknown. The resulting control structure is shown to be robustly feasible under given conditions. Knowledge about the geometry of system constraints is exploited to obtain a computationally efficient method of computing tightened sets online. A simulation study is presented demonstrating the ability of the controller to handle modelling error and demonstrate tracking of a commanded power profile.

  • 20.
    Brugård, Jan
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Mean Value Engine Modeling of a Turbo Charged Spark Ignited Engine: A Principle Study2001Report (Other academic)
    Abstract [en]

    Object oriented modeling of physical systems is an interesting paradigm, which has the potential to offer reusable models and model components. The aim of this study i to investigate how to build mean value models for automotive engines. MathModelica, a modeling tool for the object oriented modeling language Modelica, is used in this study. Several sub models have been developed for the different parts of the engine. Th models cover the air filter, intercooler, throttle, base engien, exhaust system, compressor, turbine, turbine shaft, and volumes. It is shown how the components can be connected to form both turbo charged engines as well as a naturally aspirated engines, which shows that the paradigm is applicable for the modeling and confirms the modeling principle. One problem that has popped up att several occasions is the selection of initial conditions for the simulation. Especially when restrictions with low pressure drops are connected between two volumes, the simulation engine has problems finding initial conditions. The models have been compared to measured engine data collected at a test bench in Vehicular Systems laboratory at Linköping University. The agreement with measurement data is good and the models work as expected.

  • 21.
    Criscuolo, Ivan
    et al.
    Department of Mechanical Engineering, University of Salerno, Fisciano, Italy.
    Leufvén, Oskar
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Thomasson, Andreas
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Model-Based Boost Pressure Control with System Voltage Disturbance Rejection2011In: Proceedings of the 18th IFAC World Congress, 2011 / [ed] Bittanti, Sergio, Cenedese, Angelo, Zampieri, Sandro, International Federation of Automatic Control (IFAC) , 2011, 5058-5063 p.Conference paper (Refereed)
    Abstract [en]

    Actuation systems for automotive boost control incorporate a vacuum tank and PWM controlled vacuum valves to increase the boosting system flexibility. Physical models for the actuator system are constructed using measurement data from a dynamometer with an engine having a two stage turbo system. The actuator model is integrated in a complete Mean Value Engine Model and a boost pressure controller is constructed. The developed model is used as basis for a nonlinear compensator, that is capable of rejecting disturbances from system voltage. An IMC based boost pressure controller is developed for the vacuum actuator and engine by using the engine model and then tested on the test cell. The controller performance is quantified and system voltage disturbance rejection is demonstrated.

  • 22.
    Edlund, Simon
    et al.
    Nokia Svenska AB, Linköping, SWEDEN.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Pettersson, Magnus
    SCANIA AB, Södertälje. SWEDEN.
    A Real-Time Platform for Collaboration Projects in Power Train Modeling and Control1999Conference paper (Refereed)
    Abstract [en]

    The requirements on research and development in automotive control are growing fast, and therefore convenient and efficient ways to make prototype experiments and demonstrations are sought for. Collaboration projects put some additional constraints on the experimental system used due to issues of safety and secrecy. These requirements are outlined, a real-time platform is developed, and experiences from some collaboration projects between industry and academia are discussed.

  • 23.
    Ekberg, Kristoffer
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Sivertsson, Martin
    Linköping University, Department of Electrical Engineering. Linköping University, Faculty of Science & Engineering.
    Cycle Beating - An Analysis of the Boundaries During Vehicle Testing2016In: IFAC PAPERS ONLINE, ELSEVIER SCIENCE BV , 2016, Vol. 49, no 11, 657-664 p.Conference paper (Refereed)
    Abstract [en]

    Todays vehicle industry is strictly controlled by environmental legislations. The vehicle industry is spending much money out reducing the fuel consumption and fulfilling the emission requirements to make sales possible in different regions in the world. Before introducing; a vehicle on the market, it is tested according to standardized driving cycles to specify the vehicle pollutant emissions and fuel consumption. These cycles allow some deviation from the reference vehicle speed during tests, e.g. NEDC allows deviations of +/- 2 km/h and +/- 1 s. This paper uses dynamic programming to find fuel optimal velocity profiles, given the allowed deviations of +/- 2 km/h and +/- 1 s from reference speed during drive cycle test. By taking advantage of the allowed deviation, the fuel consumption can be reduced by up to 16.56 % according to model results, ruoriing NEDC if gear selections are unrestricted (i.e. using automatic gearbox), and up to 5.90 % if changing gears according to the specifications in the drive cycle. Two different optimization goals are investigated, minimum amount of mass fuel consumed and best mileage. (C) 2016, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.

  • 24.
    Eriksson, Daniel
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Frisk, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Krysander, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Analysis and optimization with the Kullback-Leibler divergence for misfire detection using estimated torque2013Report (Other academic)
    Abstract [en]

    Engine misfire detection is an important part of the On-Board Diagnostics (OBDII) legislations to reduce exhaust emissions and avoid damage to the catalytic converters. The flywheel angular velocity signal is analyzed, investigating how to use the signal in order to best detect misfires. An algorithm for engine misfire detection is proposed based on the flywheel angular velocity signal. The flywheel signal is used to estimate the torque at the flywheel and a test quantity is designed by weighting and thresholding the samples of estimated torque related to one combustion. During the development process, the Kullback-Leibler divergence is used to analyze the ability to detect a misfire given a test quantity and how the misfire detectability performance varies depending on, e.g., load and speed. The Kullback-Leibler divergence is also used for parameter optimization to maximize the difference between misfire data and fault-free data. Evaluation shows that the proposed misfire detection algorithm is able to have a low probability of false alarms while having a low probability of missed detections.

  • 25.
    Eriksson, Daniel
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Frisk, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Krysander, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Flywheel angular velocity model for misfire and driveline disturbance simulation2013In: Proceedings of the 7th IFAC Symposium on Advances in Automotive Control, The International Federation of Automatic Control, Elsevier, 2013, Vol. 46, no 21, 570-575 p.Conference paper (Refereed)
    Abstract [en]

    A flywheel angular velocity model for misfire and disturbance simulation is presented. Applications of the model are, for example, initial parameter calibration and robustness analysis of misfire detection algorithms. An analytical cylinder pressure model is used to model cylinder torque and a multi-body model with torsional flexibilities is used to model crankshaft and driveline oscillations. Misfires, cylinder variations, changes in auxiliary load, and flywheel manufacturing errors can be injected in the model and the resulting speed variations can be simulated. A qualitative validation of the model shows that simulated angular velocity captures the amplitude and oscillatory behavior of measurement data and the effects of different phenomena, such as misfire and flywheel manufacturing errors.

  • 26.
    Eriksson, Daniel
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Frisk, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Krysander, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Flywheel angular velocity model for misfire simulation2013Manuscript (preprint) (Other academic)
    Abstract [en]

    A flywheel angular velocity model for misfire and disturbance simulation is presented. Applications of the model are, for example, initial parameter calibration or robustness analysis of misfire detection algorithms. An analytical model of cylinder pressure is used to model cylinder torque and a multi-body model is used to model crankshaft and driveline oscillations. Different types of disturbances, such as cylinder variations, changes in auxiliary load, and flywheel manufacturing errors can be injected in the model. A qualitative validation of the model shows that simulated angular velocity captures the amplitude and oscillatory behavior of real measurements and the effects of different types of disturbances, e.g. misfire and flywheel manufacturing errors.

  • 27.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    A European Perspective on Collaborative Research in Modeling and Control of Turbocharged Engines2014In: Journal of the Society of Instrument and Control Engineers, ISSN 0453-4662, Vol. 53, no 8, 716-724 p.Article in journal (Refereed)
    Abstract [en]

    Modeling and simulation plays an important role in the design of the control systems for advanced power­trains. One clear trend is that turbocharged engines are becoming more common and are also being equipped with more than one boosting device. To systematicaUy handle these advanced turbocharging concepts we need to build more knowledge and this knowledge is encap­sulated in models. Recent results for modeling and control of compres­sors in advanced engines are provided.   In particular the experimental results from a large measurement cam-paign with engine and gas stand hardware an;\ sum­marized as rules of thumb extrapolating manufacturer compressor data. Thereafter, system properties öf V­engines with pa.rallel turbocharging is investigated and used to illustrate applications of the newly developed modeling knowledge. It is used to niodel, simulate and analyzc a compressor instability phenomenon that gives rise to an oscillation. A detection scheme and a con­troller is also developed and it is shown to quell the oscillation. Finally the benefits of academic and industrial collab­oration, that play an important role in the authors lab as well as in many European institutes, are commented upon. A concluding remark is that thc works that are summarized would not have been possible without the cooperation between academy and industry.

  • 28.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    A Real-Time Platform for Spark Advance Control1997Report (Other academic)
    Abstract [en]

    With the aim at spark advance control, a method for estimating the peak pressure position (PPP) from the ionization current has previously been developed and off-line validated. To implement the concept on an engine a real-time platform is needed. A hardware platform, that consists of a PC, an electronic engine control unit (ECU), and a synchronization circuit, is described. The platform synchronizes the data acquisition with the engine and the functionality is validated. Also a refined interpretation algorithm for estimating the PPP is described and validated to give a good estimate. The algorithm is suitable for implementation on the described real-time platform.

  • 29.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    CHEPP – A Chemical Equilibrium Program Package for Matlab2005In: SAE technical paper series, ISSN 0148-7191, Vol. 4, no 113, 730-741 p.Article in journal (Refereed)
    Abstract [en]

    A program package, that calculates chemical equilibrium and thermodynamic properties of reactants and products of a combustion reaction between fuel and air, has been developed and validated. The package consists of the following four parts: 1) A program for calculating chemical equilibrium. 2) A database that contains thermochemical information about the molecules, which comes from the GRI-Mech tables. 3) A GUI that allows the user to easily select fuels, fuel/air ratio for the reaction, and combustion products. 4) A set of functions designed to access the thermochemical database and the chemical equilibrium programs. Results are validated against both the NASA equilibrium program (Gordon and McBride, 1994) and the program developed by Olikara and Borman (1975). It is shown that the new method gives results identical to those well recognized Fortran programs.

  • 30.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Development of a Hardware and Software Platform that Constitutes a Step Towards Adaptive Engine Control1998Conference paper (Refereed)
  • 31.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Documentation for the Chemical Equilibrium Program Package CHEPP2000Report (Other academic)
    Abstract [en]

    A program package has been developed that calculates chemical equilibrium and thermodynamic properties of reactants and products of a combustion reaction between fuel and air. The package consists of the following four parts: 1) A program for calculating chemical equilibrium. 2) A database that contains thermochemical information about the molecules, which comes from the GRI-Mech tables. 3) A GUI that allows the user to easily select fuels, fuel/air ratio for the reaction, and combustion products. 4) A set of functions designed to access the thermochemical database and the chemical equilibrium programs. The program package is validated with respect to how well it can reproduce results shown in the standard literature. The thermodynamic properties for the individual molecules and the results from the equilibrium calculation all agree with the results shown in the literature. There is almost perfect agreement, between the results produced by the program package and those shown in the book by Heywood, when comparing the thermodynamic properties of the mixture of equilibrium products.

  • 32.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Increasing the Efficiency of SI-Engines by Spark Advance Control and Water Injection1997Report (Other academic)
    Abstract [en]

    By directly measuring in-cylinder parameters and adjusting the spark advance, the engine efficiency can be maximized. A feedback scheme for spark-advance control using the ionization current as sensed variable has earlier been presented. One issue is to verify that the algorithm works when the environmental conditions changes the burn rate. Humidity significantly affects the burn rate and active water injection is used to slow down the combustion giving a peak pressure position (PPP) that occurs too late. The ionization current based feedback-scheme adjusts the spark advance, and moves the PPP back to optimum. An additional result is that the engine efficiency can be increased by combining active supply of water to the combustion and the spark-advance control scheme.

  • 33.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Les rencontres scientifiques d’IFP energies nouvelles RHEVE 2011: International Scientific Conference on Hybrid and Electric Vehicles2013In: Oil & Gas Science and Technology: Revue de l'Institut Français du Pétrole, ISSN 1294-4475, Vol. 68, no 1, 9-12 p.Article in journal (Other academic)
  • 34.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Mean Value Models for Exhaust System Temperatures2003In: SAE technical paper series, ISSN 0148-7191, Vol. 111, no 3Article in journal (Refereed)
    Abstract [en]

    Exhaust temperatures are important for turbine and catalyst performance. A set of exhaust temperature models suitable for turbo matching as well as design and analysis of engine control systems are developed and investigated. The models are lumped parameter heat transfer models, that fall within the category of mean value engine models. The model is developed for describing exit temperatures from the exhaust manifold and temperature drops in pipe sections in the exhaust system. The components used to model the exhaust temperature are: engine out temperature, temperature drop in a straight pipe, and a set of heat transfer modes. The model is validated using data from three different engines. It is shown that, for a spark ignited engine operating at MBT and stoichiometric conditions, it is sufficient to model the engine out temperature as a linear function of mass flow. Recommendations for tuning the model are also given. A thorough survey of exhaust heat transfer literature is also made together with a comparative summary of the different heat transfer modes that are present in the exhaust.

  • 35.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Methods for Ionization Current Interpretation to be Used in Ignition Control1995Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is desirable to measure engine performance for several reasons, e.g. when computing the spark advance setting in spark-ignited (SI) engines. There exists two methods, among others, of measuring the performance, such as measuring the pressure and the ionization current. Since the ionization current reflects the pressure, it is interesting to study if it is possible to extract information from the ionization current about the combustion and pressure.

    Three different algorithms for extracting information from the ionization current are studied. The first algorithm, ion peak, searches the \second peak" in the ionization signal. The second algorithm computes the centroid. In the third algorithm a model of the ionization signal structure is fitted to the ionization signal.

    The algorithms are tested in four operating conditions. The first algorithm uses the local information around the second peak and is sensitive to noise. The second algorithm uses a larger portion of the ionization signal, which is more stable. It provides promising results for engines with a clear post flame phase. The third algorithm, ion structure analysis, fits an ideal model to the ionization signal. The algorithm provides promising results, but the present implementation requires much computational effort.

  • 36.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Modeling and Control of Supercharged SI and CI Engines2006In: Proceedings of New Trends in Engine Control, Simulation and Modelling, 2006Conference paper (Refereed)
    Abstract [en]

    A component based modeling methodology for turbocharged engines is described and applied. Several component models are compiled and reviewed. In addition new models are developed for the compressor efficiency, compressor flow, and turbine flow. Two application examples are finally given where the modeling methodology and the component models have been used. The applications are: Observer design and air/fuel ratio control of SI engines. Control design of DI engines with VGT and EGR.

    CONFERENCE INFORMATION: Les Rencontres Scientifiques de l’IFP : "New Trends in Engine Control, Simulation and Modelling" 2-4 October 2006, IFP, Rueil-Malmaison, France

  • 37.
    Eriksson, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Modeling and Control of Turbocharged SI and DI Engines2006Conference paper (Refereed)
  • 38.
    Eriksson, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Modeling and Control of Turbocharged SI and DI Engines2007In: Oil & gas science and technology, ISSN 1294-4475, Vol. 62, no 4, 523-538 p.Article in journal (Refereed)
  • 39.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Requirements for and a Systematic Method for Identifying Heat-Release Model Parameters1998In: SAE technical paper series, ISSN 0148-7191, Vol. 107, 898-908 p.Article in journal (Refereed)
    Abstract [en]

    Heat release analysis by using a pressure sensor signal is a well recognized technique for evaluation of the combustion event, and also for combustion diagnostics. The analysis includes tuning of several parameters in order to accurately explain measured data. This work presents and investigates a systematic method for estimating parameters in heat release models and minimizing the arbitrary choices. In order for the procedure to be systematic there are also the requirements on the model, that it includes no inherent ambiguities, like over-parameterization with respect to the parameters and to the information contained in the measurements. The fundamental question is which parameters, in the heat release model, that can be identified by using only cylinder pressure data. The parameter estimation is based on established techniques, that constructs a predictor for the model and then minimizes a least-squares objective function of the prediction error. The study is performed on data measured on a SAAB 2.3 liter, four stroke four cylinder, normally aspirated, gasoline engine.

  • 40.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Simulation of a vehicle in longitudinal motion with clutch engagement and release2001Conference paper (Refereed)
    Abstract [en]

    A simple model for driver and vehicle in longitudinal motion is developed and simulated. The focus is on describing and handling simulation of clutch lock and clutch release which changes the model structure, both during start and gear shifts, in Simulink. Special attention is given the problem of simulating start and stop of a vehicle with rolling resistance at zero speed. Only principles for simulating the system with variable structure is of interest and therefore the models are maintained at lowest possible complexity. The system is successfully simulated and the validation is performed using three scenarios: one with only clutch lock and clutch release, one with start and stop of vehicle, and one full European drive-cycle.

  • 41.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Spark Advance for Optimal Efficiency1999In: SAE technical paper series, ISSN 0148-7191, Vol. 108, 789-798 p.Article in journal (Refereed)
    Abstract [en]

    Most of todays spark-advance controllers operate in open loop but there are several benefits of using feed-back or adaptive schemes based on variables deduced from the cylinder pressure. A systematic study of how different engine conditions change the deduced variables, at optimal ignition timing, is performed. The analysis is performed using a one-zone heat-release model and varying the model parameters. The deduced variables that are studied are: position of the pressure peak, mass fraction burned levels of 30%, 45%, 50%, and 90%, and the pressure ratio. For MBT timing the position for 45% mass fraction burned changed least under a large variety of changes in burn rate. Cycle-to-cycle variations do not have a significant effect and it suffices to evaluate the mean values for the burn rate parameters. The pressure ratio produces values similar to the mass fraction burned and requires no separate treatment.

  • 42.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    VehProLib - Vehicle Propulsion Library, Library development issues2003In: Proceedings of the 3rd International Modelica Conference, Linköping, November 3-4, 2003Conference paper (Refereed)
    Abstract [en]

    A Modelica library called Vehicle Propulsion Library is under development. Its structure and important design issues are described and the current status is shown. The vehicle propulsion library aims at providing functionality for studying and analyzing the performance of different powertrain configurations. The included components cover the range from zero dimensional in-cylinder models to longitudinal models for complete vehicles.

  • 43.
    Eriksson, Lars
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Andersson, Ingemar
    Chalmers.
    An Analytic Model for Cylinder Pressure in a Four Stroke SI Engine2003In: SAE technical paper series, ISSN 0148-7191, Vol. 111, no 3Article in journal (Refereed)
    Abstract [en]

    An analytic model for cylinder pressures in spark ignited engines is developed and validated. The main result is a model expressed in closed form that describe the in-cylinder pressure development of an SI engine. The method is based on a parameterization of the ideal Otto cycle and takes variations in spark advance and air-to-fuel ratio into account. The model consists of a set of tuning parameters that all have a physical meaning. Experimental validation on two engines show that it is possible to describe the in-cylinder pressure of a spark ignited combustion engine operating close to stoichiometric conditions, as a function of crank angle, manifold pressure, manifold temperature and spark timing.

  • 44.
    Eriksson, Lars
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Frei, Simon
    Onder, Christopher
    Guzzella, Lino
    Control and Optimization of Turbo Charged Spark Ignited Engines2002Conference paper (Refereed)
    Abstract [en]

    The subject of this study is the trade-off between fuel economy and transient performance in turbocharged engines. It quantifies the losses and gains of different engine control strategies. Two extreme strategies are analyzed, one for optimal fuel economy and the other for fast transient response. Models for the components that influence the fuel economy are developed and described. An optimization problem for best fuel economy is solved analytically and a fuel-optimal controller is implemented based on that result. This controller is compared to one which is optimized for fast transient response with respect to the gains in fuel economy and losses in transient response. Simulations of a highly boosted engine show that a fuel-optimal controller can improve the fuel economy of a vehicle operated at cruising speed by 1-3% and at highway speed by 4%, and that the highest achievable improvement is above 10%. The losses in transient response are around 0.4 s for cruising conditions. Furthermore, measurements on a low-boosted engine on a test bench are used to show that the fuel-optimal controller reduces fuel consumption by 1.9% at highway conditions.

  • 45.
    Eriksson, Lars
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Larsson, Anders
    Scania CV AB, Sweden.
    Thomasson, Andreas
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    The AAC2016 Benchmark - Look-Ahead Control of Heavy Duty Trucks on Open Roads2016In: IFAC PAPERSONLINE, ELSEVIER SCIENCE BV , 2016, Vol. 49, no 11, 121-127 p.Conference paper (Refereed)
    Abstract [en]

    A benchmark problem for fuel efficient control of a truck with engine, driveline, and chassi models on a given mission with a road topography profile is formulated. The Vehicle model is provided with open access to the vehicle model equations and parameters. It is compiled from model components validated in previous research projects and the result is a non-linear model that contains mixed continuous and discrete control variables. The driving; scenario is provided as road slope profile and a desired trip time. The problem to solve is a combination of engine-, driveline- and Vehicle-control while fulfilling demands on emissions, driving time, legislative speed, and engine protections. (C) 2016, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.

  • 46.
    Eriksson, Lars
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Lindell, Tobias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Leufvén, Oskar
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Thomasson, Andreas
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Scalable Component-Based Modeling for Optimizing Engines with Supercharging, E-Boost and Turbocompound Concepts2012In: SAE International Journal of Engines, ISSN 1946-3936, E-ISSN 1946-3944, Vol. 5, no 2, 579-595 p.Article in journal (Refereed)
    Abstract [en]

    Downsizing and turbocharging is a proven technology for fuel consumption reduction in vehicles. To further improve the performance, electrified components in the turbocharger arrangements have been proposed, and investigations have shown acceleration improvements, emission reductions, and further fuel conversion efficiency benefits. Simulation tools play an important role in the design process as the interplay between component selection, control strategy, system properties and constraints is very complex. Evaluations are performed with respect to BSFC map, fuel consumption in a drive cycle, acceleration performance, as well as many other aspects. A component-based engine and vehicle model is developed and evaluated to facilitate the process of assessing and optimizing the performance of e.g. engine, charging system, and electrical machine components. Considerations of the execution time and model fidelity have resulted in a choice of models in the mean value engine model family. The turbocharging and electrical system models have all been evaluated using experimental data from engine dynamometer tests and turbocharger gas stand measurements and other dedicated component measurements.

  • 47.
    Eriksson, Lars
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Nezhadali, Vaheed
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Andersson, Conny
    Linköping University.
    Compressor Flow Extrapolation and Library Design for the Modelica Vehicle Propulsion Library - VehProLib2016In: SAE 2016 World Congress and Exhibition, SAE International , 2016, 2016-01-1037Conference paper (Refereed)
    Abstract [en]

    Modelbased systems engineering is becoming an important tool when meeting the challenges of developing the complex future vehicles that fulfill the customers and legislators ever increasing demands for reduced pollutants and fuel consumption. To be able to work systematically and efficiently it is desirable to have a library of components that can be adjusted and adapted to each new situation. Turbocharged engines are complex and the compressor model serves as an in-depth example of how a library can be designed, incorporating the basic physics and allowing fine tuning as more information becomes available. A major part of the paper is the summary and compilation of a set of rules of thumb for compressor map extrapolation. The considerations discussed are extrapolation to surge, extrapolation to restriction region, and extrapolation out to choking. Furthermore the compressor diameter is coupled to the maximum performance of the compressor such as maximum speed, mass flow, and pressure ratio. All this is a result of an analysis of a database of more than 300 compressors. The paper uses the compressor modeling to discuss how wishes for extendability and reuse of component performance influences the library design. A Modelica library named Vehicle Propulsion Library VehProLib has been developed to meet these goals by including basic components that give a starting point for modeling and at the same time allows reuse and extendablility.

  • 48.
    Eriksson, Lars
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Increasing the Efficiency of SI-Engines by Spark-Advance Control and Water Injection1998Conference paper (Refereed)
    Abstract [en]

    Engine efficiency can be maximized by directly measuring in-cylinder parameters and adjusting the spark advance, using a feedback scheme based on the ionization current as sensed variable. Water injection is shown to increase the engine efficiency, if at the same time the spark advance is also changed when water is injected to obtain maximum efficiency. A spark-advance control scheme, that takes the water injection into account, is thus necessary to increase the efficiency.

  • 49.
    Eriksson, Lars
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Ionization Current Interpretation for Ignition Control in Internal Combustion Engines1997In: Control Engineering Practice, ISSN 0967-0661, E-ISSN 1873-6939, Vol. 5, no 8, 1107-1113 p.Article in journal (Refereed)
    Abstract [en]

    Spark advance setting in spark-ignited engines is used to place the in-cylinder pressure curve relative to the top dead center. A feedback scheme, not a calibration scheme, based on ionization current is proposed here. It is thus related to pressure sensor feedback schemes, that have reported good results, but have not yet been proved cost effective, due to the cost of the pressure sensor. The method proposed here is very cost-effective, since it uses exactly the same hardware and instrumentation (already used in production cars) that is used to utilize the spark plug as a sensor to detect misfire and as a sensor for knock control. A key idea in the method is to use parameterized functions to describe the ionization current. These parameterized functions are used to separate out the different phases of the ionization current. Special emphasis is laid on getting a correct description of the pressure development. The results are validated on a SAAB 2.3 l production engine by direct comparison with an in-cylinder pressure sensor (used only for validation, not for control), but also by using a physical model relating the ionization current to the pressure.

  • 50.
    Eriksson, Lars
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Modeling and control of engines and drivelines2014Book (Refereed)
1234 1 - 50 of 183
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf