Calculation of Magnetic Fields Generated by Traction Transformers and Busbars in Electric Locomotive Systems by Finite Element Method

Abstract

The effects of the magnetic field intensity created around the power system equipment on human health are examined by various organizations. Permissible limit values have been determined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) when people are exposed to the magnetic field intensity generated by the power system equipment at a low frequency. Accordingly, the maximum allowable magnetic field intensity values for public areas and working environments are specified as 0.2mT and 1mT, respectively. In this context, it is seen that the magnetic field intensity generated by components such as traction transformer, busbar, driver, and motor used to provide traction power in locomotives are essential parameters. Therefore, it is recommended that the magnetic field intensities around these components remain below the limits for the health of passengers and personnel. For this reason, it is necessary to determine the magnetic field intensities around the components during the design phase of the locomotive systems. This study aimed to calculate the magnetic field densities generated by a traction transformer and a sample busbar structure used in locomotives. For this purpose, the geometric model of the traction transformer, a simple locomotive casing, and busbar structure was created in a three-dimensional coordinate system and transferred to the Ansys Electronics Suite finite element analysis software, and analysis studies were carried out. Finally, it is seen that the magnetic field intensities in the measurement planes determined according to the analysis results are below the limit values. Since the magnetic field intensity values change depending on the geometric structure of the model, material parameters, and operational status, the necessity of evaluating these analyses at the design stage has been emphasized within the scope of the study.