An analysis of existing models for hydraulic servo valves is presented for use in simulations of a camless engine actuator. Because of the limitations of the accepted models, a new servo valve model is derived, presented and verified. The updated model allows for more complex internal geometry, including new port shapes and port lapping parameters. Comparative results are presented, outlining the significant improvement in valve lift versus time simulation of the newly derived model. The improved model results allow for better simulations and control system design for camless engine valve actuators.
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