Sökning: "Electrical conductivity"

Visar resultat 21 - 25 av 340 avhandlingar innehållade orden Electrical conductivity.

  1. 21. The Effects of Lightning on Low Voltage Power Networks

    Författare :Raul Montaño; Vernon Cooray; Marcos Rubinstein; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical engineering; Lightning induced effects; Lightning Electromagnetic fields; Electromagnetic Compatibility EMC ; Surge Protective Devices SPDs ; Low voltage power networks; Elektroteknik; elektronik och fotonik; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

    Sammanfattning : The present society is highly dependant on complex electronics systems, which have a low damage threshold level. Therefore, there is a high risk of partial or total loss of the system’s electronics when they are exposed to a thunderstorm environment. LÄS MER

  3. 22. Surface potential dynamics on insulating polymers for HVDC applications

    Författare :Shahid Alam; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dielectric spectroscopy; silicone rubber; intrinsic conduction; surface potential decay; activation energy; electric conductivity; HVDC insulation;

    Sammanfattning : The use of high voltage direct current (HVDC) technology in power transmission systems is continuously expanding. Nowadays, HVDC transmissions operate at voltages up to 800 kV and higher levels are being developed. LÄS MER

  4. 23. Partial Discharge Analysis of Stator Insulation at Arbitrary Voltage Waveform Stimulus

    Författare :Xiaolei Wang; Hans Edin; Joachim Holböll; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Partial discharge (PD) detection is a powerful tool to diagnose the defects and degradation in high voltage electrical insulation systems. It can be performed in both on-line and off-line conditions. LÄS MER

  5. 24. Electron microscopy studies of tungsten oxides in the range WO₃ - WO₂˔₇₂ : phase relations, defect structures, structural transformations and electrical conductivity

    Författare :Wubeshet Sahle; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Oorganisk kemi; Volfram;

    Sammanfattning : The article reviews recent studies of structural variations in the W-O system in the composition range of WO3-WO2.72. Several types of defect structures have been observed in high resolution electron microscopy studies and defect models have been proposed. LÄS MER

  7. 25. Carbon Based Materials Synthesis and Characterization for 3D Integrated Electronics

    Författare :Shuangxi Sun; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TIM; G-CNT; electrical resistivity; VA-CNTs; thermal resistance; 3D IC integration; TSV; graphene; VA-CNT-Solder; VA-CNT-Cu;

    Sammanfattning : 3D IC packaging technology extends Moore’s law and shifts the IC field into a new generation of smaller, but more powerful devices. Interconnection and thermal management as two critical parts of 3D IC integration packaging, are facing harsh challenges due to the miniaturization of IC devices. LÄS MER