Sensorless position estimating and transition time identifying for the spool of a high speed on/off solenoid valve

In this paper, a sensorless method of detecting the spool position high-speed on/off solenoid valve is presented. The depends on analyzing time-current curve coil passing current and measuring maximum stroke spool, such that dynamic behavior estimated displacement plotted. A mathematical model developed effect hydraulic force studied. Experimental results show proposed error less than 7% when compared to measured by commonly used linear variable transducer.