The field of internal combustion engines has been evolving since their invention, which dates back to the second half of nineteenth century. One of the potential improvements of internal combustion engines is also on the control system of the intake and exhaust valves. Internal combustion engines could have cleaner combustion and would even slightly improve efficiency with optimal independent valve control. Whether the newly developed or invented solution comes to serial production or not, it depends mainly on reliability of solution, its cost and emission regulations.
In the first chapter is presented a brief summary of the literature on the role of intake and exhaust valves in the internal combustion engines. The key parameters of the valves and their influence on internal combustion engine operation are described. These parameters determine the valve opening, the valve duration and the intake and exhaust valve overlap. There are also listed benefits, which can be achieved with individual control of these parameters. Based on these benefits is also based the motivation fort this research.
The second and the third chapter contain a brief summary of the literature review in the field of advanced individual valve control systems. The second chapter shortly presents existing conventional mechanical solutions, continuing with brief literature summary of advanced hydraulic, pneumatic, piezo and electromagnetic control approaches, that enable individual control of the valves. Third chapter is focused on electromagnetic solutions for individual valve control.
The fourth chapter presents the concept of design and optimisation of a multi-pole reluctance electromechanical converter designed for individual valve control. The presentation covers explanation of the theoretical background and the meaning and contribution of the geometry used. A model of the actuator for electromagnetic simulations is presented briefly, and computer aided design model for the construction of first prototype sample.
T. Munih: Zasnova in optimizacija večpolnega reluktančnega elektromehanskega pretvornika
The fifth chapter presents the analytical model of the designed actuator. The analytical model covers the electromagnetic and mechanical circuit, and thus enables rapid analytical simulations of the actuator's response, depending on the different input control strategies. The model is intended for better knowledge and understanding of actuator's transient response. It is also very supportive in analysing the appropriate control strategies.
The sixth chapter briefly presents the manufactured prototype. Shortly is presented designed and produced appropriate controller for the measurements, analyses of the transient responses and control strategies. Chapter continues with presentation of performed measurements, and their comparison with the simulated and calculated results. The comparison shows good matching of the results, with the exception in the area of starting region. There are also presented identified reasons for the result deviations in the starting region and justified with additional measurements and analyses. The actuator was also installed on the intake valve of a single cylinder diesel engine.
In the seventh chapter we introduced two control strategies for the control of presented and developed actuator concept. Strategies were verified and used on manufactured sample of the actuator.
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