Abstract:A proportional raise valve was designed to meet the requirement of electro-hydraulic rockshaft on big-power tractors. The flow rate characteristics of four types of regulator orifice were analyzed. The mathematical model of the valve was established based on state space method, then the stable performance and dynamic performance of the valve were simulated by using Matlab/Simulink. An indoor test-bed was built to test the designed proportional raise valve. The results showed that the valve core with half-round regulator orifice had shorter travel and better low-flow rate characteristics. The coefficient of determination of the linearity of flow rate curve due to the control current change was 0.9986. The overshoot of step response was 6.25% and the set up time was 0.3 s.