Electromagnetic field and thermal distribution optimisation in shell‐type traction transformers

Abstract

This study presents a method for analysing the eddy current distribution in splints and oil tank and investigates the losses because of eddy currents in a shell-type power transformer. An optimisation algorithm combining the Taguchi's and the Rosenbrock's method to decrease the eddy current losses is proposed based on an optimal placement and sizing approach of splints and magnetic shielding plates. The thermal distribution of the splints and the oil tank equipped with magnetic shielding is analysed. Results show the effectiveness of the proposed method because of a significant reduction of eddy current losses and a well-distributed temperature profile.

HST calculation of a 10 kV oil‐immersed transformer with 3D coupled‐field method

“…Metal structure parts inside the transformer will cause eddy current losses under the influence of leakage magnetic field, which may affect the oil flow in the transformer to a certain extent, and it may affect the HST simulation accuracy. The eddy current losses in splints and oil tank of a shell‐type power transformer were investigated in [14] with the finite‐element method (FEM). On the basis of the FEM method, the stray losses of the structural parts for an ODFS‐334 MVA/500 kV single‐phase auto‐transformer were investigated, and those losses were used as the heat source to calculate temperature rise in those structural parts [15].…”

Oil exponent thermal modelling for traction transformer under multiple overloads

“…However, due to the restrictions of related standards [18] and the consideration of capacity and safety, long‐time heat tests under overload are not allowed. Besides the experimental tests, numerical simulation [19, 20] based on the finite element method or the finite volume method, physical modelling [21–25] based on fluid mechanics, heat transfer theory, and electrical loss are effective means to explore local characteristics and solve specific thermal parameters in the transformer. However, as previously mentioned, the oil exponent is different among different transformers and this inconsistency (heterogeneity) will be amplified under overload.…”

Evaluation of ultraviolet ageing, pollution and varistor degradation effects on harmonic contents of surge arrester leakage current

“…For condition monitoring of surge arresters, many offline and online approaches have been presented in literature such as power loss method [2], Voltage-current (V-I ) characteristic curve analysis [3], leakage current measurement [4][5][6][7], temperature measurement [8][9][10] and electro-magnetic field measurement [11,12]. Thermo-vision and electromagnetic tests are non-destructive monitoring methods which are used for surge arresters condition monitoring.…”