This paper presents the describing equations of a pressurecompensated poppet valve; the magnitude and phase relationships of the open-loop system are examined, and stability predictions made, using Nyquist techniques. Effects of chang ing the valve mass, valve-cavity volumes, and the lengths of supply and discharge lines are discussed.
Experimental data are presented on the observed system instability for various line lengths, valve-cavity volumes, and valve masses. The results of these studies are compared to the computer predictions, and other experimental observations are discussed.
The usefulness of Nyquist's criteria in analyzing the stability of the hydraulic poppet valve is discussed with respect to the problem of determining the location of poles of the open loop.