A new non-dimensional approach to the explicit characterization of the non-linear steady state performance of an axial piston motor is presented. The motor is driven by a servovalve and it is shown how the flow characteristics, including losses, may be sufficiently represented by a well-established single equation that may then be used to produce directly usable design equations for speed, efficiency, and power transfer. This has not been previously deduced and the new equations allow direct determination of the conditions for maximum efficiency and power transfer, which leads to the establishment of new conclusions regarding the effect of flow and torque losses for both open-loop and closed-loop operation. The approach is validated by experimental results.
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