直動形油圧サーボ弁における静的状態量の測定 Measurement of Static State Variables in a Direct Drive Electro-Hydraulic Servovalve
Making use of a direct drive servovalve's driving current, which is in proportion to the driving force, and the spool displacement obtained from a built-in LVDT, it is possible to get the state variables such as flow force, flow rate and load pressure for the purpose of valve control without attaching other transducers on the servovalve. In this paper, experiments were carried out using different loads. With PWM driving, no hysteresis appeared regardless of the flow rate. Because of the flow force compensation on the spool of the valve used in the experiment, an empirical equation was used for calculation of the flow rates from the measured flow forces. Under different loads, the calculated flow rates were in consistence with the measured ones. Then, load pressures were obtained from the calculated flow rates, with the discharge coefficients acquired using empirical equations. The calculated load pressures were in good agreement with the measured results.
日本油空圧学会論文集 30(6), 147-151, 1999-09-15
The Japan Fluid Power System Society