A detailed analysis is given of a flow-compensated, two-stage, four-way, closed-ports electrohydraulic flow-control valve. Factors considered in the analysis of the first stage include: the electromagnetic forces generated by the torque motor, impedance of the motor coil, inertia of the flapper, viscous damping forces, spring forces, pressure feedback forces, and leakage flow. Factors considered in the analysis of the second stage include the acceleration force on the spool, viscous friction forces, restraining spring forces, flow reaction forces, leakage flow, and the compressibility of the oil.
Experimental verification of the analytical work is included.
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