New method of identifying dead zone of hydraulic proportional directional valve

To observe the dynamic characteristics of the pressure at outlets of proportional valves,a new method of identifying the dead zone of the proportional directional valve was proposed.The common dead zone of the hydraulic valve is caused by non-flow within certain zone of the spool since the spool of slide valve covers valve ports to some extent.Nonlinearity of the dead zone is one of the key factors affecting the static and the dynamic performances of proportional valves,and the dead zone is usually eliminated through the addition of compensation within controllers.As a rule,the compensation is estimated through a set of parameters with expensive flow sensors being required.However,the new method of identifying the parameters of the dead zone only needed pressure sensor.The results show that the new method has lower cost and faster speed.