Dead zone compensation method of zero position control of double electromagnet proportional direction valve
                                                      ZHANG Jiaxu1, YU Yaxin1, WENG Zhidan2, JIN Bo3, GUO Qiang3
(1.College of Mechanical and Automatic Control, Zhejiang SciTech University, Hangzhou 310018,China;2.Ningbo HOYEA Machinery Manufacture, Ningbo 315153,China; 3.Department of Mechanical Engineering, Zhejiang University, Hangzhou 310027, China)

Abstract: Aiming at the problem of proportional directional valve position control in zero position，which is driven by two electromagnet and with valve center position sensor, the valve center position control system was modeled by Simulink, the cause of zero dead zone was studied. The influence of the factors forming zero dead zone on the time of dead zone was analyzed by simulation. The compensation strategies of zero current step and attenuated position instruction jump were proposed according to different factors, and the compensation performances of different compensation methods were compared. Finally, it was verified by experiments.The results indicate that the dead zone of zero position control and response waveform of the valve，which due to the nonlinear and timevarying system can be effectively eliminated by the position control compensation method.

Key words: zero position dead zone; position compensation; current step; proportional directional valve; valve core