Justification Of The Calculation Of The Dynamic Characteristics Of Porlarized Monostable Electromagnets For Vacuum Switching Devices Using The Combined Method

The paper considers the combined method of calculating the dynamic characteristics of a polarized electromagnet, which is used as a drive in vacuum contactors and medium voltage vacuum circuit breakers. The design of a monostable polarized electromagnet and the peculiarities of its operation during the switching on and off are considered. A calculation femm model of an electromagnet in a cylindrical coordinate system has been developed. The theoretical substantiation of the improved combined method of calculating the dynamic characteristics of an axially symmetric monostable polarized electromagnet, which is based on the numerical solution of the static equations of the electromagnetic field by the finite element method and the numerical solution of the transient equations of a nonlinear electric circuit, a magnetic circuit taking into account eddy currents, and nonlinear equations of motion is carried out. The developed combined calculation method allows to determine the current in the winding, the displacements and speed of the armature, the dependence of the armature pressing force to the stationary part of the magnetic core on the time of powering the coil winding during the operation of switching on the electromagnet, which is a necessary condition for designing such devices.