A new algorithm for identification of flow-rate characteristics of pneumatic solenoid valves — Based on the isothermal discharge method

To improve the identification precision of flow-rate characteristics of pneumatic solenoid valves, a new algorithm called Cbm algorithm is proposed. The error formation mechanism of current algorithm defined by the ISO6358/DIS-3 is analyzed. The Cbm algorithm has reduced the errors of pressure derivative by changing the calculation procedure of multivariable optimization. Five pneumatic solenoid valves are tested to compare the identification precision of different algorithms. The comparison results show that the Cbm algorithm improves the identification precision of flow-rate characteristics. The identification errors of sonic conductance of the Cbm algorithm are less than 4%, and the identification errors of critical pressure ratio of the Cbm algorithm are less than 10%.