Abstract
This study concerns with a semi-active damper, in which a pressure regulating mechanism similar to a balanced piston-type relief valve is built-in. In the previous paper, a mathematical model for the damper was derived and it was pointed out by numerical simulation that the system is less stable in the extended stroke than in the compressed stroke. The present paper focuses on the stability of the extended stroke. A modified equivalent model has been proposed to obtain the steady operating point. The effects of system parameters on the stability are investigated on the basis of this model. Furthermore, the effect of the damping coefficient of the pilot valve is investigated by a reduced order model, and it is clarified that the increase in the damping of the pilot valve deteriorates the stability of the system.
