Numerical Calculation and Experimental Verification for Leakage Magnetic Field and Temperature Rise of Transformer Core Tie-Plate

According to the actual structure and operation of the transformer, the test model of transformer core tie-plate (TCTP) is designed, and radial magnetic flux density and temperature rise of TCTP surface are measured. In order to reduce solution scale of three-dimensional (3-D) magnetic field, the stray losses in TCTP, tank, and other structural parts are obtained by using 3-D finite element method with surface impedance boundary condition. Then, TCTP temperature rises in different schemes are also calculated by magneto-thermal-fluid weak coupling method. The effectiveness of the used method is validated by comparison of the tested and calculated values of both radial flux density and temperature rise on TCTP surface. It is shown by analysis results that the actual distribution of the temperature rise can be reflected more accurately by the calculation method used in this paper, which provides a more efficient and reliable analysis method to optimize its structure and prevent occurrence of overheating of TCTP.