Mechanism Modeling and Parameters Identification of Pneumatic Booster Mass Flow

Pneumatic amplifier is not only the commonly used independent electrical attachment but also one of key components of the valve positioner. In this paper, a mass flow mechanism model of the typical pneumatic amplifier is established, and the method of parameter identification is proposed. Firstly, according to the working principle and structural characteristics of the pneumatic amplifier, the mass flow model of the pneumatic amplifier is established by using the principle of thermodynamics and fluid mechanics. Secondly, a new sub model is established for the important equivalent orifice area by the experimental study, and the parameter identification is carried out. Finally, the model is verified by the experimental platform of the control valve. The results show that the accuracy of the model is up to 90% compared with the actual typical pneumatic amplifier.