A Study on the Electromagnetic Field Characteristics of Two-Inverter System of Three-Phase Motor Assuming a Failure

Abstract

In order to consider the control stability and performance of the motor, it is required to analyze what kind of electromagnetic characteristics it has when the motor is faulty. Therefore, in order to secure the stability of the motor control, an analysis is performed to determine the electromagnetic characteristics of the motor in case of a defect. The number of inverter controllers generally used to control traction motors is one. However, in the case of a failure in the two-inverter system applied for the purpose of reducing the current burden of the controller when controlling the motor, finite element analysis is performed through simulation to analyze the change in the electromagnetic characteristics of the motor. As a result, it was found that there is no problem in the operation of the motor, but the current consumption must be increased due to the increase in torque ripple and phase voltage. At the base speed, it can be seen that the difference in back EMF between channels 1 and 2 is small, but in the field weakening region (high speed region), the torque ripple increases and the difference in back EMF between channels 1 and 2 is extremely large. The key point is that the method proposed in this paper not only reduces the current burden on the inverter during wiring, but also enables operation even when one inverter fails.