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Showing result 1 - 5 of 338 swedish dissertations matching the above criteria.

  1. 1. Electrical Characterisations of Bearings

    Author : Abhishek Joshi; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ball bearing; Equivalent circuit model; Lubricants; Bearing Capacitance; Spherical bearing; Mechanical bearing; Bearing currents; Electrical conduction; Electrical characterisation;

    Abstract : Mechanical bearings are an integral part of industry, and are used in various places in order to reduce friction between two interacting surfaces and are used to transmit power and loads. Mechanical bearings are one of the most extensively used components within the wind industry, but on the other hand they are also one of the most dominantly failing failed components. READ MORE

  2. 2. High resolution electrical characterization of III-V materials and devices

    Author : Olivier Douheret; Srinivasan Anand; Wilfried Vandervorst; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical engineering; condensed matter; electrics; electrical; materials science; Elektroteknik; elektronik och fotonik; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

    Abstract : The continuing shrinkage of semiconductor devices towards nanoscale features and increased functionality has prompted a strong need for high-resolution characterization tools capable of mapping the electrical properties with nanoscale lateral resolution. In this regard, scanning capacitance microscopy (SCM) scanning spreading resistance microscopy (SSRM) and Kelvin probe force microscopy (KPFM) have emerged as powerful techniques. READ MORE

  3. 3. Characterization of Conduction and Polarization Properties of HVDC Cable XLPE Insulation Materials

    Author : Hossein Ghorbani; Hans Edin; Gilbert Teyssedre; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC insulation; power cable insulation; cross-linked polyethylene insulation; conductivity; dielectric losses; space charge; Electrical Engineering; Elektro- och systemteknik;

    Abstract : High voltage direct current (HVDC) cables with extruded insulation system were introduced in 1998. Since then this technology has been growing rapidly with many installations that are today operational at voltages up to 320 kV. READ MORE

  4. 4. Characterization of Conduction and Polarization Properties of HVDC Cable XLPE Insulation Materials

    Author : Hossein Ghorbani; Hans Edin; Erling Ildstad; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC insulation; power cable insulation; cross-linked polyethylene insulation; conductivity; dielectric losses; space charge; HVDC isolation; kraftkabel isolation; tvärbunden polyeten isolationsmaterial; elektrisk ledningsförmåga; dielektriska förluster; rymdladdning; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Since its first introduction in 1998, extruded direct current (DC) cable technology has been growing rapidly leading to many cable system installations with operation voltages up to 320 kV. Cable manufacturers invest heavily on technology development in this field and today extruded DC cable systems for operation voltages as high as 525 kV are commercially available. READ MORE

  5. 5. Diagnosis of Moisture in Transformer Insulation - Application of frequency domain spectroscopy

    Author : Chandima Ekanayake; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; moisture content; diagnostic methods; modelling; polarisation depolarisation currents PDC ; frequency domain spectroscopy FDS ; dielectric response measurements; Oil-impregnated pressboard paper insulation; Karl Fischer titration KFT ; conductivity; ageing;

    Abstract : This thesis presents application of dielectric response measurements for identifying condition of high voltage insulation in power transformers. Results of such measurements, incorporated with different modelling techniques, allow to estimate moisture content in solid part of transformer insulation. READ MORE