Reduced-Order Modeling of Traction Transformer Considering Coupling of Electric-Thermal-Fluid Multi-physical Domains

The operating condition of the traction transformer has an important impact on the safe and smooth operation of the traction power supply system. It should be noted that the temperature distribution can reflect the operating state of the transformer. Therefore, it is necessary to study the transformer temperature field. The numerical models commonly used at present to solve the temperature field are computationally costly in terms of time and difficult to derive the temperature in real-time. In order to solve this problem, the reduced-order modeling of transformers in coupled multi-physical domains is proposed in the paper. First, a full-order three-dimensional model of the traction transformer is established and the accuracy of the model is verified. Second, the reduced-order model is obtained by mode analysis based on the full-order model. Finally, the reduced-order model is applied to solve the temperature field, and the calculation error and time of different models are compared. The results show that the error between the calculated values of the reduced-order model and the full-order model is within 0.05 °C while the calculation time is improved by 3 times compared with the full-order model, which verifies the accuracy and timeliness of the reduced-order model.