A Frequency-Domain Model of Electromagnetic Actuators Composed of Solid Iron Cores With Hysteresis Effects

A model in the frequency domain is considered and checked with experimental results for the dynamic characteristics of magnetic actuators with solid iron core. First, an analytical magnetic reluctance based on a two-dimensional analysis is approximated in a simple form with a half-power of frequency and an accompanying complex number. This approximation is used to describe the dynamic characteristics of the electromagnet system with a C-shaped stator. Magnetic hysteresis effect is considered with a simple phase shift and with the conception of a complex value of permeability; leakage flux is ignored. The model is given by relations in the form of Laplace transform with the variation of working air-gap. For the symmetric electromagnet system with a uniform cross-sectional area, the frequency responses are compared with the experimental results when the working air-gap is fixed.