Analysis of Performance Effect Factors of Three-Stage Electro-Hydraulic Servo Valve

TAbstract T— A new modeling software, AMEsim is put forward in this paper to develop a nonlinear model for a higher performance three stage electro-hydraulic servo valve. The simulation results and experimental results on existing valve are consistent, which proves that the developed model is right. The analysis of the model shows that pilot valve bandwidth mainly affects the bandwidth of three-stage electro-hydraulic servo valve and is responsible for overshoot. The analysis also indicates that pilot valve resolution affects the resolution of three-stage electrohydraulic servo valve and pilot valve rated flow affects the bandwidth and overshoot. The result further reveal that the position transducer affects the bandwidth and overshoot, servo controller affects the bandwidth and stability, the spool diameter and mass affect the bandwidth and hydraulic natural frequency, flow force on spool affects the bandwidth, overlap distance of restriction edge affects the dead zone size of mid-position and resolution of midposition, coulomb friction force between spool and sleeve affects the resolution and radial clearance affects leakage flow and resolution. The analytical results are very useful because the methods can be applied to other similar systems.