Experimental procedure to obtain electromagnetic properties of A-36 low carbon steel plates utilized in transformers

Aragon-Verduzco, D. A.; Olivares-Galván, J. C.; Escarela‐Perez, R.; Campero‐Littlewood, E.; Ocon-Valdez, Rodrigo; Magdaleno-Adame, Salvador

doi:10.1109/tdc-la.2016.7805679

Cited by 4 publications

(13 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, these differences are not so significant, and thus the analyses of their results can be performed on the basis of an average behavior. Thus, in Figure 6(a), a graphic with the results of the volumetric losses, obtained by Aragon-Verduzco et al (2016), is added as a reference in view of the comparison to the results obtained using the proposed method. In fact, the results obtained using the two different methods are significantly similar and show a very good agreement.…”

Section: Analyses Of the Resultsmentioning

confidence: 99%

“…Similarly, the behavior of the AC magnetization curve, shown in Figure 6(b), is also compared to that of (Aragon-Verduzco et al, 2016). In this case, the results obtained using the proposed method, for Toroids A and B, keep a very close similarity, mutually, whereas they significantly differ from the results of (Aragon-Verduzco et al, 2016). Nonetheless, the essence of the difference is basically due to a factor scale, whereas the behavior is basically the same for both methods, which is somehow in accordance with the literature.…”

Section: Analyses Of the Resultsmentioning

confidence: 99%

“…Regarding the magnetic permeability of the ASTM A36 steel, Table III shows the values obtained using the proposed method, in average, for different values of magnetic flux density, ranging from 0.5 to 1.5 T. For the sake of comparison, the corresponding values of the relative magnetic permeability, obtained by Aragon-Verduzco et al (2016) are also given. Thus, because of the significant difference between the values of the relative magnetic permeability for a same value of magnetic flux density, the skin effect of the distribution of the magnetic flux density over the cross section of the magnetic circuits arises as being one of the most likely reasons for such this difference.…”

Section: Separation Of Lossesmentioning

confidence: 99%

“…On the other hand, to obtain these data by testing a sample of a structural steel through a conventional Epstein frame is not so feasible because of the dimensional incompatibility between it and any minimally representative sample of a structural steel. On the other hand, despite the exceptional case of the work of (Aragon-Verduzco et al, 2016) obtaining these data by testing samples of a structural steel through a conventional Epstein frame is not so feasible because of the dimensional incompatibility between it and any minimally representative sample of a structural steel. Nonetheless, this work presents the proposal of a relatively simpler, alternative and new experimental method to obtain these important data.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Experimental evaluation of electric and magnetic properties of structural steel

Piccoli

Cabral

Oliveira³

et al. 2018

COMPEL

View full text Add to dashboard Cite

Purpose This paper aims to present the proposition of a new experimental method for obtaining very crucial data of the structural steel that is used in the tank of oil filled power transformers, namely, the volumetric losses and the magnetic permeability, both in function of the density of magnetic flux. Although these data are not usually available, they are fundamental for helping the transformer designer in avoiding the occurrence of hot spots in the transformer tank. The adoption of a conventional Epstein frame has restrictions because of the incompatibility between it and the samples of the steel. Design/methodology/approach The basis of the proposition is the same as that of the Epstein frame, with significant attention paid to the additional losses in the winding that creates the magnetic flux to the samples in the core. These losses can be significant and are created by the harmonics of current along the windings and are summed to the ohmic losses. For separating these winding losses from the magnetic losses, each sample is made as being the core of a toroidal 1:1 transformer. Thus, two tests with two identic of these toroidal transformers are necessary. Findings The proposed methodology is simple, because it is very similar to the classical tests of transformers (no-load and short-circuit tests). The process of separation of losses requires only a numerical fitting of curves for adjusting the winding losses as a function of the current amplitude, and the obtained results are coherent with the expected behavior of the magnetic losses and the magnetic permeability of a structural steel. Research limitations/implications The method gives very approximate results in comparison to those obtained using the Epstein frame. The influences of the temperature and/or of the skin effect have not been evaluated. Practical implications Practical, real and thus confident data of structural steel, such as the magnetic permeability and the volumetric losses (hysteresis and Foucault), become available for the transformer designer to take actions for not only reducing the tank losses but also for avoiding the occurrence of hot spots through computer simulation. Originality/value The proposition is very new, as it allows to test steel samples with a size that does not fit to a usual Epstein frame. It takes into account the real influence of harmonic of currents in the losses along the winding of a classical Epstein frame, which has not been so far mentioned. It allows obtaining data of structural steel that had not been considered important until now.

show abstract

Section: Analyses Of the Resultsmentioning

confidence: 99%

Section: Analyses Of the Resultsmentioning

confidence: 99%

Section: Separation Of Lossesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Experimental evaluation of electric and magnetic properties of structural steel

Piccoli

Cabral

Oliveira³

et al. 2018

COMPEL

View full text Add to dashboard Cite

show abstract

“…On the other hand, by depending on the amplitude of the leakage magnetic field, the so developed eddy losses can become quite significant, which implies in loss of efficiency as well as in the occurrence of hot spots. Thus, although such these issues have been addressed and published for the steady-state operation of power transformers [1][2][3][4], the evaluation of the losses within these structural parts has not been equally diffused for the transient state, as in the case of inrush currents or GICs events. Moreover, the influence of power harmonics on these losses, as in the case of a transformer supplying a variable frequency driver (VFD) that is becoming more and more frequent has become a very significant issue for transformer designers to consider.…”

Section: Introductionmentioning

confidence: 99%

Alternative model for computing transformer tank induced losses in the time domain

Oliveira¹,

Sadowski²,

Cabral³

2020

IET Electric Power Applications

View full text Add to dashboard Cite

In the performance evaluation of power transformers, the occurrence of eddy currents and their effects on the transformer tank have been widely modelled and studied for the cases of power frequency in the steady state. Nonetheless, for the cases when harmonic components are present (zero‐sequence flux) or for transient conditions (inrush or geomagnetically induced current (GIC) events) there is much to do. With this aim, this work presents the proposal in using temporal modelling for evaluating eddy currents in transformer tank walls in practical cases of sinusoidal, harmonic and transient excitations. Obtained results are compared with consolidated commercially available software based on finite elements for showing how good this proposition is.

show abstract

Análisis térmico de los elementos de sujeción del núcleo de un reactor trifásico

González¹

View full text Add to dashboard Cite

In this thesis work the temperature distribution in the frame bolts of a 5 MVA, 115 kV, 60 Hz, three-phase five-limbs shunt reactor is obtained utilizing the finite element method (FEM) and the commercial ANSYS Maxwell software. This because the reactor actually failed while it was running, the failure occurred progressively as the screw insulation was damaged and caused an unwanted temperature rise. A time-harmonic analysis is performed to compute the magnetic field distribution in the reactor and the power losses in the frame bolts. A three-dimensional (3-D) shunt reactor model is utilized, and Maxwell’s equations are solved utilizing scalar and vectorial magnetic potentials. The 3-D electromagnetic shunt reactor model is validated by comparing the value of inductance measured in the laboratory with the value of inductance computed in the 3-D FE simulation. In addition, the core losses computed in the FE simulation are compared with the core losses measured in the laboratory. This thesis work is important for transformer manufacturers which requires an adequate shunt reactor model to analyze it under different operation conditions and to optimize the actual design.

show abstract

Experimental procedure to obtain electromagnetic properties of A-36 low carbon steel plates utilized in transformers

Cited by 4 publications

References 10 publications

Experimental evaluation of electric and magnetic properties of structural steel

Experimental evaluation of electric and magnetic properties of structural steel

Alternative model for computing transformer tank induced losses in the time domain

Análisis térmico de los elementos de sujeción del núcleo de un reactor trifásico

Contact Info

Product

Resources

About