The influence of the dispersion flux on the connection transient regime for DC electromagnets

The aim of the present paper is to analyze the behavior of the direct current electromagnets with null starting flux (when the initial position of the mobile armature does not meet the mechanical equilibrium) in dynamic regime. The electromagnets are considered as electromechanical energy conversion systems with two degrees of freedom, one electric (magnetic) and another mechanic [1]. The behavior of these electromagnetic devices is described by using typical mathematical systems of differential equations which can be solve with the finite difference method and iterative calculation of the characteristic parameters. The papers discuss about the influence of the dispersion magnetic flux from the connection process that can be translated into a decrease of the useful flux found at the electromagnet air gap, which also leads to a decrease of the electromagnetic force of the device. All this factors contribute at the increase of the connection time. By using modern methods for calculation, monitor of the parameters evolution with appropriate software (Mathcad 15) for a U-I electromagnet type supplied by a direct current power supply, was developed an algorithm which can determine the parameters values in the connection process. (displacement of the armature, total magnetic flux, dispersion magnetic flux etc.).