Search for dissertations about: "Göran Bergqvist"

Found 4 swedish dissertations containing the words Göran Bergqvist.

  1. 1. On methods of measuring magnetic properties of power transformers

    Author : Claes Carrander; Göran Engdahl; Anders Bergqvist; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; No-load; magnetizing current; losses; diagnostics; delta; three-phase; power transformer; magnetic core; electrical steel; measurements; simulation; Electrical Engineering; Elektro- och systemteknik;

    Abstract : The core of a power transformer can weigh hundreds of tons, and represents a significant part of the total ownership cost of the transformer, in terms of both the construction cost and of the monetary cost of losses. It is therefore desirable to have a method of diagnosing the core to ensure optimal performance, and to enable the operator to plan repairs of damaged or defective cores. READ MORE

  2. 2. The Chevreton Superenergy Tensor in Einstein-Maxwell Spacetimes

    Author : Ingemar Eriksson; Göran Bergqvist; Paul Todd; Linköpings universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Einstein-Maxwell; graviational energy; superenergy; Bel tensor; Chevreton tensor; conservation laws; Conformal Einstein space; Theory of relativity; gravitation; Relativitetsteori; gravitation;

    Abstract : In this thesis we investigate the superenergy tensor that was introduced by Chevreton in 1964 as an electromagnetic counterpart to the Bel-Robinson tensor for the gravitational feld.We show that in Einstein-Maxwell spacetimes with a source-free electromagnetic feld, the Chevreton superenergy tensor has many interesting properties. READ MORE

  3. 3. Dimensionally dependent identities and the Lanczos potential

    Author : Anders Höglund; Göran Bergqvist; Linköpings universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP;

    Abstract : To antisymmetrize over more indices than the number of dimensions gives a dimensionally dependent identity. In this thesis such identities for tensors, spinors and matrices are discussed and some new results are presented which generalise earlier results of Lovelock. READ MORE

  4. 4. Spinors, Clifford algebras and superenergy tensors

    Author : Paul Lankinen; Göran Bergqvist; James Vickers; Mälardalens högskola; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; MATHEMATICS; MATEMATIK; Matematik tillämpad matematik;

    Abstract : .... READ MORE