Modeling, simulation and robust control of an electro-pneumatic actuator for a variable geometry turbocharger (original) (raw)
Related papers
2012
This work has been performed at the System and Transports (SeT) laboratory, under the supervision of Prof. M. El Bagdouri and Dr. S. Laghrouche. This work would not have been possible without their motivation, enthusiasm and immense knowledge. First, I would like to thank both of my supervisors for all the support and encouragement they have provided during this work. I would also like to thank them for providing me an opportunity to work with project partners of SIMBA (SIMulation de la Boucle d'Air) from industry. I would like to thank the jury members: Prof. X. Brun and Prof. H. Chafouk for reviewing my thesis and giving me very useful remarks on the report. I am also very thankful to Prof. A. El Moudni and Prof. M. Basset for their participation as examiners in the jury. This project was realized with collaboration of Faurecia Emissions Control Technologies, Honeywell Turbo Technologies and Mark IV. I am also grateful to Mr. D. Ragot from Faurecia, Mr. D. Guyon from Mark IV and Mr. J. S. Roux from Honeywell for their guidance and technical support which helped me to solve technical issues related to my thesis. My colleagues certainly deserve a mention since they have significantly contributed not only to my work but also to my social life. Special thanks to Mr. F. S. Ahmed for his help for conducting experiments on the test bench, Mr. M. Harmouche for helping me to sort out bugs in control theory, Mr. I. Matraji, A. El Amroui and K. Dar for their moral support and organizing the outdoor activities which made my stay very memorable in Belfort. Last but not the least, I would like to say special thanks to my parents and other family members for their continues support and love throughout my life. They were always v vi CONTENTS there to celebrate my success and to overcome the fear of failures in my life. Their unconditional support helped me to accomplish this objective with courage and enthusiasm.
Modeling and Identification of Electro-Pneumatic VNT Actuator for Simulation and Control
8th IFAC Symposium on Nonlinear Control Systems, 2010
An accurate non-linear model based control of the electro-pneumatic actuator adjoined to a Variable Nozzle Turbocharger (VNT) is proposed in this paper. Electro-pneumatic actuator is composed of electro-pneumatic pressure converter (EPC) coupled to pneumatic actuator. A precise physical model which captures fundamental dynamics of pneumatic actuator and its interaction with EPC is proposed. Dynamics of the pressure inside the actuator chamber are modeled, considering variation in volume and the temperature, along with EPC controlled air mass flow to the actuator. Modeling of air-leakage phenomenon in the EPC is also addressed. Comparison between simulation and experimental results shows the effectiveness of the proposed model.
Experimental setup for turbocharger control
This paper presents the mechanical details regarding a new control test rig for laboratory use. A variable geometry turbocharger is this system central part. In this paper it will be shown how this rotating machine can be decoupled from the internal combustion engine and fitted in a testbench where a computer emulates the vehicle’s motor. In order to accomplish this, a dozen of mechanical parts were designed and built. In addition, a set of sensors and actuators was adapted to the system. This article will show the final result of a system that will be used to test several different control strategies, with relevance given to the coefficient diagram method.
Nonlinear Modeling of the VNT Pneumatic Actuator with Aero-dynamic Force
IFAC Proceedings Volumes, 2010
This paper describes a physical model of an industrial pneumatic actuator used to control variable nozzle turbocharger (VNT). Friction force, that causes hysteresis, is identified using Dahl friction model. Model is tested and compared with experimental results, provided by Honeywell Turbo Technologies (HTT), at different engine conditions. Aerodynamic force acting on the turbocharger is modeled and identified as a function of pressure ratio across turbine and vane angle of the VNT. Comparison between simulation results and experimental results shows the effectiveness of the proposed model.
Energy Conversion and Management, 2014
This paper provides a reliable tool for simulating the effects of exhaust gas flow through the variable turbine geometry section of a variable geometry turbocharger (VGT), on flow control mechanism. The main objective is to estimate the resistive aerodynamic force exerted by the flow upon the variable geometry vanes and the controlling actuator, in order to improve the control of vane angles. To achieve this, a 1D model of the exhaust flow is developed using Navier-Stokes equations. As the flow characteristics depend upon the volute geometry, impeller blade force and the existing viscous friction, the related source terms (losses) are also included in the model. In order to guarantee stability, an implicit numerical solver has been developed for the resolution of the Navier-Stokes problem. The resulting simulation tool has been validated through comparison with experimentally obtained values of turbine inlet pressure and the aerodynamic force as measured at the actuator shaft. The simulator shows good compliance with experimental results.
A Dynamic Model of an Electropneumatic Valve Actuator for Internal Combustion Engines
Journal of Dynamic Systems, Measurement, and Control, 2010
This paper presents a detailed model of a novel electropneumatic valve actuator for both engine intake and exhaust valves. The valve actuator’s main function is to provide variable valve timing and variable lift capabilities in an internal combustion engine. The pneumatic actuation is used to open the valve and the hydraulic latch mechanism is used to hold the valve open and to reduce valve seating velocity. This combination of pneumatic and hydraulic mechanisms allows the system to operate under low pressure with an energy saving mode. It extracts the full pneumatic energy to open the valve and use the hydraulic latch that consumes almost no energy to hold the valve open. A system dynamics analysis is provided and followed by mathematical modeling. This dynamic model is based on Newton’s law, mass conservation, and thermodynamic principles. The air compressibility and liquid compressibility in the hydraulic latch are modeled, and the discontinuous nonlinearity of the compressible f...
Active Control Turbocharger for Automotive Application: An Experimental Evaluation
8th International Conference on Turbochargers and Turbocharging, 2006
The current paper presents the results from a comprehensive set of experimental tests on a prototype active control turbocharger. This is a continuing series of test work as part of the development of this new type of turbocharger. Driven by the need to comply to increasingly strict emissions regulations as well as a continuing strive for better overall performance the active control turbocharger is intended to provide an improvement over the current state-of-the-art in turbocharging. In this system, the nozzle is able to alter the throat inlet area of the turbine according to the pressure variation of each engine exhaust gas pulse thus imposing a substantially more 'active' form of control of the conditions at the turbine rotor inlet.
Issues in the integration of active control turbochargers with internal combustion engines
International Journal of Automotive Technology, 2012
The application of active control means to regulate the flow of exhaust gas in a turbocharger turbine is a concept developed by the Turbomachinery Group at Imperial College, London. It is a new concept the first results of which were made public in 2004. This paper presents the theoretical grounding behind the idea, its development and the elements required for a successful implementation of active control for a turbocharger turbine and the integration of such a turbocharger system within an internal combustion engine. This paper is intended to fill a gap in the theoretical understanding of the issues pertaining to the concept of Active Control for Turbocharger Turbines. The discussion is led towards a theory summarising the flow physics and their effect on the behaviour of the exhaust gas flow occurring during turbocharger turbine inlet geometrical changes and the implications from the periodic nature of these geometric changes in particular with respect to cycle performance results both for the turbocharger and for the engine. This paper is written with the purpose of presenting a realistic context of ACT operation by identifying and considering those parameters relevant to the operation and successful application of ACT to an internal combustion engine. In addition, the requirements for a dedicated ACT control strategy which can be effective in the ACT-engine integrated environment are, also, highlighted.
Study of the nonlinear control techniques for single acting VGT pneumatic actuator
International Journal of Vehicle Design, 2012
In this paper, we have developed a detailed mathematical model of a pneumatic actuator for a Variable Geometry Turbocharger (VGT) equipped with an Electro-pneumatic Pressure Converter (EPC). This model may require complex calculations for control purpose; therefore the dynamics of the EPC have been neglected and replaced by a static gain. These models incorporate friction and aerodynamic force related effects by using adaptive LuGre model. To compensate for parametric uncertainties, two single-input single-output nonlinear position control laws are designed using the second order sliding mode (SMC) and backstepping control. A comparative study with experiments shows the effectiveness of the proposed controllers.
IEEE Transactions on Industrial Electronics, 2018
Electrical turbocharger assist is one of the most critical technologies in improving fuel efficiency of conventional powertrain vehicles. However, strong challenges lie in high efficient operations of the device due to its complexity. In this paper, an integrated framework on characterization, control, and testing of the electrical turbocharger assist is proposed. Starting from a physical characterization of the engine, the controllability and the impact of the electrical turbocharger assist on fuel economy and exhaust emissions are both analyzed. A multivariable robust controller is designed to regulate the dynamics of the electrified turbocharged engine in a systematic approach. To minimize the fuel consumption in real time, a supervisory level controller is designed to update the setpoints of key controlled variables in an optimal way. Furthermore, a cutting-edge experimental platform based on a heavy-duty diesel engine is built. The proposed framework has been evaluated in simulations, physical simulations, and experiments. Results are presented for the developed system and the proposed framework that demonstrate excellent tracking performance, high robustness, and the potential for improvements in fuel efficiency. Index Terms-Electrical turbocharger assist (ETA), multivariable control, real-time energy management, system characterization, testing framework design. NOMENCLATURE GHG Greenhouse gas. EM Electrical machine. ETA Electrical turbocharger assist. TDE Turbocharged diesel engine. ETDE Electrified turbocharged diesel engine.