Multifunctional optimal design of an electromagnetic valve actuator with hybrid magnetomotive force for a camless engine

This paper proposes a novel design of an electromagnetic valve actuation system for internal combustion engines. This electromagnetic valve uses a hybrid magnetomotive force with a permanent magnet and electromagnet to control the variable timing and soft landing of the valve. Under the restriction of engine space and operation, the dynamics of the electromagnetic valve are modeled with an equivalent magnetic circuit, which is used to perform both sensitivity analysis and an optimal design function to satisfy multiple objectives, such as magnetic holding force, release current, and its rising time. The final design is verified and refined by finite element analysis. A prototype is fabricated and the experimental results show that the dynamical performances of the electromagnetic valve are satisfactory and may be improved by advanced feedback controls.