Mathematical modeling of energy efficient field reduction systems of traction motor for ac electric locomotives

This article describes the standard field reduction system of traction electric motors of a contactor-resistors type using inductive shunts, its drawbacks are revealed. An improved field reduction system of traction electric motors of an AC locomotive based on IGBT transistors has been developed and proposed. The proposed solution will allow to exclude the copper-containing inductive shunt from the power circuit, while providing reliable protection in non-stationary operating modes of the electric locomotive, as well as reduce electricity consumption for train traction. To prove the advantages of the proposed the field reduction system of traction electric motors, a method of comparative analysis of electromagnetic processes of the mathematical model of the standard and proposed systems of the field reduction of traction electric motors of an electric locomotive obtained in the MatLab Simulink environment was applied. As a result, it is proved that the implementation of the field reduction systems of traction electric motors using IGBT transistors with the developed control algorithm provides an increase in the power factor of an electric locomotive on average by at least 4%, and also significantly reduces the ripple current of the traction electric motor.