Numerical calculation of the non-linear dynamic process in electromagnetic devices

A direct coupling model is developed that can be used in analyzing the two-dimensional nonlinear transient magnetic field in electromagnetic devices excited by a voltage source. The relevant numerical method is presented for calculation of the dynamic characteristic of the devices. In the method, mechanical movement, eddy currents, exciting electric circuit, and the nonlinear problem of the magnetic material are taken into account. The direct coupling method is used for solving the transient magnetic field. The numerical technique that modifies the nonsymmetric coefficient matrix to a symmetric and banded one with edges has considerably reduced the computer memory capacity needed and the CPU time. An example of an application is given for a brake electromagnet system