Results 61 to 70 of about 420 (253)

FIRST-ORDER PERTURBATION APPROACH TO TRANSFORMER WINDING DEFORMATIONS

Progress In Electromagnetics Research Letters, 2013
An on-line method to detect radial mechanical deforma- tions of power transformer winding turns is presented. First-order perturbation theory is applied to a transformer winding surrounded by the transformer tank wall and the iron core. The transformer wind- ing is modeled as thin conducting cylindrical rings (winding segments or turns) situated within
Mariana Dalarsson, Martin Norgren
openaire   +1 more source

Hydrogen‐Assisted Fracture of Iron‐Based Fe–Ni–Al Alloys

Advanced Engineering Materials, EarlyView.
Principal relations and fracture mechanisms of single‐phase and precipitate‐strengthened Fe–Ni–Al alloys subjected to prior electrochemical hydrogen charging are identified. The mechanisms of hydrogen effect on strength and microhardness are discussed, including hydrogen‐induced increase in microhardness and the role of hydrogen in fracture behavior ...
Nataliya Yadzhak, Olha Zvirko, Rostyslav Leshchak, Hryhoriy Nykyforchyn   +3 more
wiley   +1 more source

Diagnosing Transformer Winding Deformation Faults Based on the Analysis of Binary Image Obtained From FRA Signature

IEEE Access, 2019
Frequency response analysis (FRA) has been widely accepted as a diagnostic tool for power transformer winding deformation faults. Typically, both amplitude-frequency and phase-frequency signatures are obtained by an FRA analyzer.
Zhongyong Zhao, Chenguo Yao, Chao Tang, Chengxiang Li, Fayou Yan, Syed Islam   +5 more
doaj   +1 more source

Creep‐Induced Microstructural Evolution in an A2‐B2 Superalloy

Advanced Engineering Materials, EarlyView.
A 27.3Ta‐27.3Mo‐27.3Ti‐8Cr‐10Al (at.%) refractory high‐entropy alloy with precipitation‐strengthened A2‐B2 microstructure was studied by creep tests at 1030°C, which demonstrate a transition in deformation mechanisms in the range of 100–150 MPa applied stress. This is associated with changes in dislocation–precipitate interactions. Relevant deformation
Liu Yang, Aparajita Pramanik, Sandipan Sen, Shubhashis Dixit, Marcel Muench, R. J. Vikram, Daniel Schliephake, Yolita M. Eggeler, Ankur Chauhan, Martin Heilmaier, Alexander Kauffmann   +10 more
wiley   +1 more source

Research on transformer early fault diagnosis based on fiber - optic leakage magnetic field measurement

Frontiers in Energy Research
When a severe fault occurs within a transformer, the fault current escalates rapidly, making it challenging for differential protection systems to promptly isolate the faulty transformer.
Junchao Wang, Zhixiang Tong, Kun Zhang, Yaqi Liu, Xiangli Deng, Hang Tu   +5 more
doaj   +1 more source

Influence of Test Temperature and Test Frequency on Fatigue Life of Aluminum Alloy EN AW‐2618A

Advanced Engineering Materials, EarlyView.
The influence of test temperature and test frequency on the fatigue life of EN AW‐2618A is investigated. High‐cycle fatigue tests are performed at different test temperatures and frequencies on the 1000 h/230°C overaged state. Both test parameters reduce fatigue life due to time‐dependent damage mechanisms.
Ying Han, Julian M. Rosalie, Jan Radners, Mauro Madia, Philipp von Hartrott, Birgit Skrotzki   +5 more
wiley   +1 more source

High‐Temperature Nanoindentation of Metals: Assessing Thermal Drift, Frame Compliance, and Chemical Composition Effects on the Reported Mechanical Properties

Advanced Engineering Materials, EarlyView.
Do not let thermal drift and instrument artifacts deceive high‐temperature nanoindentation results. We compare classical Oliver–Pharr and automatic image recognition analyses across steels and a Ni alloy to quantify these effects. Accounting for artifacts reveals systematic softening with temperature, while Cr and Ni additions boost resistance ...
Velislava Yonkova, Steffen Brinckmann, Ruth Schwaiger   +2 more
wiley   +1 more source

Modeling, simulation and measurement of converter transformer winding multi-frequency vibration Based on electromagnetic structure coupling

International Journal of Electrical Power & Energy Systems
The converter transformer is the key equipment of the UHV DC transmission system, assuming the function of AC/DC conversion. The electromagnetic environment and structural deformation of the converter transformer windings mutually interact under high ...
Peiyu Jiang, Fanghui Yin, Liming Wang
doaj   +1 more source

Creep Properties and Deformation Mechanism of Additively Manufactured NiAl‐CrMo Composites

Advanced Engineering Materials, EarlyView.
Additively manufactured NiAl‐CrMo composites contain numerous interfaces and cell boundaries that control their creep response. At 700°C under high applied stress, creep is dominated by dislocation‐controlled power‐law mechanisms. At 800°C–900°C and lower stresses, creep is primarily diffusion‐controlled along cell boundaries.
Jan Vollhüter, Andreas Bezold, Johan Westraadt, Katharina Fiegl, Subham Chattoraj, Benjamin Wahlmann, Carolin Körner, Michael Mills, Mathias Göken, Steffen Neumeier   +9 more
wiley   +1 more source

Recycling of NiTi Shape Memory Alloys: Fundamental and Technological Aspects of a Vacuum Induction Melting Processing Route

Advanced Engineering Materials, EarlyView.
The present study investigates recycling of NiTi shape memory alloys via vacuum induction melting. An ingot was synthesized from elemental Ni and Ti and subjected to three subsequent remelting cycles. Remelting increases process durations and impurity levels and adversely affects microstructures and functional properties.
Sakia Sophia Noorzayee, Son Tung Mai, Sarath Menon, Braulio Gadiel Sánchez Ortega, Ralf Drautz, Alexander Kauffmann, Gunther Eggeler, Jan Frenzel   +7 more
wiley   +1 more source