This thesis is concerned with the study of proportional pressure control performance of a hydraulic compound valve.
The proportional pressure control mechanism consists of a pressure compensating mechanism and an electro-magnetic pilot relief valve. The major problem in the proportional pressure control of a hydraulic compound valve is instability.
The static and dynamic characteristics of the valve system is studied theoretically and experimentally. Dynamic equations are solved by digital computer simulation. It is shown that important parameters governing the system stability are the opening areas of both chokes and the spring constant in electro-magnetic pilot relief valve.
The inductive time constant of the electro-magnet is the most significant parameter for system response.
Experimental results shown good agreement with the theory and simulation.
