Parameter identification of a hydraulic servo-valve torque motor with magnetic fluids based on dynamic characteristics

Abstract

Due to the higher saturation magnetization and magnetoviscosity of magnetic fluids when exposed to a magnetic field, magnetic fluids are filled into the working gaps of a servo-valve torque motor to improve the dynamic performance of the torque motor in this paper. After the construction and working principle of a torque motor with magnetic fluids being introduced, the mathematical models are established. Simulation and experiments on the dynamic characteristics of the torque motor are carried out. Based on the experimental data and the mathematical model of the torque motor with magnetic fluids, the estimated values of the unknown parameters are obtained by a curve-fitting parameter identification method in the least-square sense.