Limited motion actuators for automotive applications

Electromechanical limited motion linear actuators are playing an increasingly important role in electrohydraulic automotive systems. A detailed understanding of the transient field distribution within the actuator and the influence of material properties and the geometry of the moving member is a clear pre-requisite to reliably predicting the dynamic performance of any electromechanical actuation system, which in turn facilitates design optimisation including the selection of the most appropriate magnetic materials to meet a given performance specification. To this end, a comprehensive dynamic system simulation facility has been developed, which is based around the calculation of the transient magnetic field distribution by nonlinear finite element analysis and the simultaneous solution of the coupled equations governing electrical drive circuit and the coupled mechanical system