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A new kind of roller thrusttorsion coupling was designed with low friction and simple structure, the linear movement of proportional electromagnet armature can be changed into the rotation of the spool movement, at the same time, the rotary torque of spool was enlarged. With large flow and simple structure, the new kind of 2D electrohydraulic proportional directional valve (EPDV) mainly consists of roller thrusttorsion coupling and electromagnet armature, which has position feedback. Based on the principle of the roller compressiontorsion coupling, the mathematical model was established, and 2D valve was simulated by the software Matlab. Direct and pilot experiment results show that, with good input and output characteristics, the high pressure and large flow control can be achieved by this valve, the noload hysteresis is 1.0%, flow hysteresis is under 5% when system pressure is at 21MPa, and the linearity and repeating characteristic are all good. Frequency width is improved to about 12Hz at -3dB and -90°and rising time of step response is about 0.45s. The valve’s static and dynamic performance is good, and simulation analysis and experimental results are basically same, which lay foundation for its engineering application.