Symptom Related Diagnostic Procedures
ELECTROMAGNETIC SOUND IS AUDIBLE
DESCRIPTION
The electromagnetic noise of the traction motor may become more noticeable when accelerating on a steep slope (large output torque).
This occurs when the IGBT switching frequency is lowered by the traction motor inverter due to high temperature of the IGBT inside the traction motor inverter. This does not indicate a problem with the traction motor inverter characteristics or control.
This phenomenon is one of the protective controls. Refer to "Protection Control" Protection Control.