3D simulation of a power transformer considering lamination effects

Poveda-Lerma, A.; Serrano-Callergues, Guillermo; Riera-Guasp, M.; Pineda-Sánchez, Manuel; Puche-Panadero, Rubén; Pérez-Cruz, J.

doi:10.1109/isef.2017.8090685

Cited by 3 publications

(2 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The hypothetical σ conductivity of the laminated core was determined based on the material-specific power loss characteristics, core dimensions, and magnetic induction distribution. This method, considering the power losses in laminated cores, has been used by various authors [23,28,[35][36][37].…”

Section: Construction Of Cascade Current Transformers For Measuring S...mentioning

confidence: 99%

Analysis of the Operation of Cascade Current Transformers for Measurements of Short-Circuit Currents with a Non-Periodic Component with a Large Time Constant of Its Decay

Leśniewska

Olak

2022

Energies

View full text Add to dashboard Cite

Simulations of emergency states and tests of resistance of electrical devices to emergencies are performed in specialized high-power laboratories, the so-called short-circuit laboratories. For most electrical power devices, such measurements are required by international standards. The basic equipment of short-circuit testing laboratories consists of current transformers for measuring short-circuit currents. These transformers should not only enable the accurate conversion of sinusoidal currents—which is typical for conventional current transformers, but also asymmetrical short-circuit currents containing an aperiodic component, which classic current transformers cannot reproduce. Therefore, manufacturers and designers try to meet the market demands and design these special class 0.2 current transformers. To meet the high technical requirements, the field-circuit method with three-dimensional space–time analysis of electromagnetic fields was used during design, considering physical phenomena in ferromagnetic cores (i.e., hysteresis and eddy current losses) and the load of the secondary winding of the current transformer by the measurement system. The article presents simulations of secondary currents for the short-circuit current transformer model, and the results were confirmed by measurements and oscillograms of the currents flowing in the windings of the real model. The prototype of the designed short-circuit transformer meets the IEC/EN standard requirements. When measuring harmonic currents, the transformation errors meet the requirements of class 0.2. During the short-circuit current waveforms, the maximum instantaneous peak error does not exceed 1% of the error for all the subsequent maxima of the current waveform during the specified transient switching cycle. In comparison, the standard allows this error to be 10%.

show abstract

Section: Construction Of Cascade Current Transformers For Measuring S...mentioning

confidence: 99%

Analysis of the Operation of Cascade Current Transformers for Measurements of Short-Circuit Currents with a Non-Periodic Component with a Large Time Constant of Its Decay

Leśniewska

Olak

2022

Energies

View full text Add to dashboard Cite

show abstract

“…This approach is valid if the flux is uniformly distributed, as in the case of a laminated E-I core using a butt joint lapping method [15], but it is not valid for analyzing the non-uniform distribution of flux if an alternate-lap joint lapping method is used. What is presented in this paper is the simulation of the laminated E-I core of a power transformer [16] using a full 3D FEM model [17], which is able to take into account the lamination effects, even in the case of alternate-lap joint stacks. This model can provide an accurate representation of the magnetic flux distribution in the laminations and spot possible areas with high saturations and losses [18], which can be avoided with an optimized design of the core.…”

Section: Introductionmentioning

confidence: 99%

Lamination effects on a 3D model of the magnetic core of power transformers

et al. 2017

View full text Add to dashboard Cite

Abstract:In this paper the lamination effect on the model of a power transformer's core with stacked E-I structure is analyzed. The distribution of the magnetic flux in the laminations depends on the stacking method. In this work it is shown, using a 3D FEM model and an experimental prototype, that the non-uniform distribution of the flux in a laminated E-I core with alternate-lap joint stack increases substantially the average value of the magnetic flux density in the core, compared with a butt joint stack. Both the simulated model and the experimental tests show that the presence of constructive air-gaps in the E-I junctions gives rise to a zig-zag flux in the depth direction. This interlamination flux reduces the magnetic flux density in the Ipieces and increases substantially the magnetic flux density in the E-pieces, with highly saturated points that traditional 2D analysis cannot reproduce. The relation between the number of laminations included in the model, and the computational resourses needed to build it, is also evaluated in this work.

show abstract