Adjusted computer model of electromagnetic processes of an auxiliary asynchronous motor with an autonomous voltage inverter for an electric locomotive

Abstract

Introduction. The author examines the problem of improving the accuracy of computer simulation of electromagnetic processes of an auxiliary asynchronous motor of an electric locomotive with the frequency adjusted by an autonomous voltage inverter. The calculations of instantaneous motor phase currents were improved. The research justified the proposed adjustments to the computer model of a three-phase asynchronous motor to consider the skin effect in the stator and rotor windings, and the effect of the magnetic circuit saturation from leakage fluxes on the leakage inductance of the phases and, thereby, on the instantaneous phase currents. The model is necessary to enhance the reliability of the auxiliary electric drive of an electric locomotive through the correct selection of semiconductor switches for the electric motor inverter. Materials and methods. The researcher chose computer simulation using OrCAD as our research method, and the input data include experimental instantaneous phase voltages of the auxiliary asynchronous motor.Results. The article presents the results of adjusted computer simulations of instantaneous variables for steady-state engine operation and compares them with experimental data.Discussion and conclusion. The author compared the experimental and calculated data (phase current, torque, rotation speed of the auxiliary asynchronous motor of an electric locomotive) and substantiated the adjusted computer model to reduce errors in the calculation of electromagnetic processes of the electric motor. The adjusted computer model improves the accuracy of calculating the instantaneous phase currents of the motor. The calculations were performed for the steady-state operation of an asynchronous motor of the AZhV250M2RUHL2 type. The results show that the skin effect has the greatest influence on the leakage inductance of the stator winding.

Keywords

• ac electric locomotive
• auxiliary asynchronous motor
• variable frequency electric drive
• leakage inductance
• phase current
• magnetic circuit saturation
• skin effect
• computer simulation