Modified method for transformer magnetizing characteristic computation and point‐on‐wave control switching for inrush current mitigation

2019 ◽  
Vol 47 (10) ◽  
pp. 1664-1679 ◽  
Author(s):  
Abdelghani Yahiou ◽  
Abdelhafid Bayadi ◽  
Badreddine Babes
1997 ◽  
Vol 78 (05) ◽  
pp. 1360-1365 ◽  
Author(s):  
G Freyburger ◽  
S Javorschi ◽  
S Labrouche ◽  
P Bernard

SummaryThe aim of the present study was to evaluate the relative performance of five screening methods for APC resistance caused by the factor V:Q506 mutation: the original method Coatest® APC™ Resistance Chromogenix, a modified method using the same reagents but a predilution 1+4 of the plasma in a factor V deficient plasma from Stago (Stago deficient V) or from Chromogenix (V-DEF Plasma), the Coatest® APC™ Resistance V (Chromogenix), and Accelerimat™ from bioMérieux. Normalization was done against a pool of normal plasmas for the methods from Chromogenix. The study included 350 subjects, 219 were genotyped (174 FV:R506R, 42 FV:Q506R, 3 FV:Q506Q) and most of them were assessed by more than one method. Uncertainty in predicting the FV genotype was evaluated by statistical analysis, which provided a way to quantitate the performance of the different diagnostic approaches. Performance of each test was evaluated by its sensitivity, specificity, R.O.C. curves, positive and negative likelihood ratios (LR), and the overall performance was determined by two parameters derived from the LR curves : the maximum LR value obtained at the crossover of the two curves, and the distance between the two curves for LR = 10. Coatest® APC™ Resistance V and Accelerimat™ were proven to be the methods most able to discriminate for factor V:Q506, while normalization was not shown to improve the screening performance. The original method from Chromogenix was confirmed to undergo many influences (factor XII, PAI-1, thrombin- antithrombin complexes, antithrombin III, hematocrit). Although a very good improvement was provided by the newest methods, they were shown to be influenced by protein S and/or factor V levels in the sample plasma.


1969 ◽  
Vol 60 (4) ◽  
pp. 657-668 ◽  
Author(s):  
Frances J. Thomas ◽  
A. W. Steinbeck

ABSTRACT A modified method for the estimation of urinary pregnanetriol, pregnanetriol, pregnanetriolone, Δ5-pregnenetriol and tetrahydro S was investigated. The steroids, separated by chromatography, were measured quantitatively, tetrahydro S by reaction with blue tetrazolium and the other three as acetaldehydogenic substances. The excretion of these steroids was studied in suspected instances of adrenal and/or ovarian disease. Urinary pregnanetriol and tetrahydro S levels were normal in Cushing's syndrome, secondary adrenocortical carcinoma, the Stein-Leventhal syndrome, idiopathic hirsutism and hypertension. Tetrahydro S was doubtfully elevated in an instance of ectopic ACTH Cushing's syndrome. Pregnanetriol excretion was elevated in untreated cases of congenital adrenal hyperplasia and after treatment in some. Pregnanetriolone was found in all patients with congenital adrenal hyperplasia, including those receiving cortisone. Pregnanetriolone was also detected in Cushing's syndrome, secondary adrenocortical carcinoma, the Stein-Leventhal syndrome, ectopic ACTH Cushing's syndrome and suspected congenital adrenal hyperplasia. Δ5-pregnenetriol was present as a glucuronide in the Stein-Leventhal syndrome and idiopathic hirsutism. The diagnostic implications of these results are discussed.


2010 ◽  
Vol 130 (4) ◽  
pp. 430-436 ◽  
Author(s):  
Naoki Dou ◽  
Atushi Toyama ◽  
Kohki Satoh ◽  
Tadashi Naitoh ◽  
Kazuyuki Masaki

2012 ◽  
Vol 132 (6) ◽  
pp. 588-596
Author(s):  
Tadashi Naitoh ◽  
Keiki Takeda ◽  
Atsushi Toyama ◽  
Tatsuhiko Maeda

2012 ◽  
Vol 132 (3) ◽  
pp. 260-267 ◽  
Author(s):  
Tatsuhiko Maeda ◽  
Tadashi Naitoh ◽  
Atsushi Toyama ◽  
Keiki Takeda

2020 ◽  
Vol 10 (10) ◽  
pp. 20-32
Author(s):  
Aleksey A. KUVSHINOV ◽  
◽  
Vera V. VAKHNINA ◽  
Aleksey N. CHERNENKO ◽  
◽  
...  

The mathematical model of a shell-core power transformer’s magnetization branch is substantiated. By using the model, analytical expressions for the magnetizing current instantaneous values under the conditions of geomagnetic disturbances can be obtained. Quantitative assessments of the magnetizing inrush current amplitudes and durations versus the geomagnetic disturbance intensity are obtained. The dynamics of the power transformer magnetic system saturation transient and changes in the magnetization inrush current amplitudes and durations after a sudden occurrence of geomagnetic disturbances are shown. The error of estimating the magnetizing inrush current amplitudes under geomagnetic disturbances is determined based on comparison with experimental data.


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