| The main transformer of high-speed electric multiple units(EMU) is one of the most important components in locomotive. To design a suitable transformer for the locomotive, we have to face the demands of high power capacity, light weight, limite dimensions and low loss. Therefore, magnetic field emulation analysis of the transformer we designed based on finite element method become much more necessary. We can calculate characteristic quantities such as inductance and impedance by numerical approach, to make sure whether the transformer we designed accord with practical application.With the help of ANSYS, a finite element analytical software, the 3D emulate model of the main transformer of the EMU has been built based on statical magnetic scalar potential method. Acrossing the three pretreatment step of exactly structure building, accurately finite element subdivision and loading current load, we can calculate the energy in each winding or between two windings. On the basis of relation of winding energy and winding inductance at stable state, the inductance matrix of the transformer windings can be figured out. Also, the distribution of magnetic field intensity of windings and iron core along special path has been shown in this paper. To calculate the short circuit impedance between two windings, circuit equivalent method, which predigest primary circuit into T type circuit has been taken usage on the condition of ignoring the resistance of the winding. Besides, this study has constructed a simulation circuit model based on MATLAB/SIMULINK software. This model can simulate current change on running state of no-load-switching-on, short-circuit and loading. The result of simulation has shown that the steady state value of current is according to theoretical arith- metic. Of course, we can calculate short circuit impedance from the short circuit current of steady state. Comparing with experiment result, the method used in the paper is proved to be feasible. |
PDF Full Text Request