Temperature field analysis and structural optimization based on multi-physics-coupling

The hot spot temperature of an oil-immersed transformer is a critical indicator of its service life and operational performance. In this study, a detailed examination of a 66kV naturally cooled transformer is conducted by establishing a two-dimensional physical model and simulating the transient temperature field under natural oil circulation conditions using finite element software. This analysis primarily focuses on the temperature rise from the initial moment until thermal equilibrium is reached, providing insights into the thermal dynamics of the transformer. Additionally, the study investigates the behavior of the hot spot temperature under varying conditions, particularly assessing the influence of load rate and ambient temperature. The findings reveal that both factors significantly impact the hot spot temperature, thereby affecting the transformer's overall thermal performance. Furthermore, the research evaluates the effect of the oil baffle plate's position relative to the winding on heat dissipation efficiency. Results indicate that the strategic installation of an oil baffle plate can effectively reduce the hot spot temperature, with the optimal configuration being the placement of the oil baffle plate between the two windings to enhance heat dissipation performance. In conclusion, this study underscores the importance of precise thermal management in oil-immersed transformers. By comprehensively understanding the effects of load rate, ambient temperature, and the placement of oil baffle plates, it is possible to significantly improve the thermal performance and extend the service life of these transformers. This research contributes valuable knowledge to the field, offering practical guidelines for optimizing transformer design and operation.