Modelling and analysis of spring return electromagnetic valve actuator for SI engine

Abstract

In internal combustion engines, variable valve timing is one of the most important parameters that affects engine performance, fuel consumption and exhaust emission. In all engine speed values, electromechanical valve actuators (EVA) are needed for variable valve timing. EVAs allow the intake and the exhaust valves to be opened and closed at the right time by the camshaft. The valves can be opened and closed by the magnet circuits and the opening and closing time can be controlled without depending on the camshaft present in all engines. The most critical part for EVA design is the solenoid in terms of the limited space on the cylinder head, the magnetic force required to open and close the valve, the coil temperature and the valve speed. This study proposes a comprehensive design of piston-type EVA and an analysis of its performance. The simulation results of the analysis with finite element method have been verified with the experimental test results. In addition, the conventional valve profile has been compared with the EVA valve profile.