Search for dissertations about: "Transformer modelling"

Showing result 1 - 5 of 12 swedish dissertations containing the words Transformer modelling.

  1. 1. Electromagnetic transformer modelling including the ferromagnetic core

    Author : David Ribbenfjärd; Göran Engdahl; David Jiles; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Power transformer; hysteresis; dynamic hysteresis; dynamic magnetization; eddy currents; excess losses; leakage flux; winding model; core model; magnetic measurements; magnetic materials; Electric power engineering; Elkraftteknik;

    Abstract : In order to design a power transformer it is important to understand its internal electromagnetic behaviour. That can be obtained by measurements on physical transformers, analytical expressions and computer simulations. READ MORE

  2. 2. Electromagnetic Modelling of Power Transformers with DC Magnetization

    Author : Seyed Ali Mousavi; Göran Engdahl; S. V. Kulkarni; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transformer; Hysteresis; DC magnetization; GICs; FEM; reluctance network method;

    Abstract : DC currents that flow through the ground can be injected to the star windings of power transformers from their grounded neutral points and close their path with transmission lines. The geomagnetically induced currents (GICs) and AC/DC convertors of high voltage direct current (HVDC) systems are the sources of such DC currents. READ MORE

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

    Author : Chandima Ekanayake; Chalmers University of Technology; []
    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

  4. 4. Electromagnetic Modelling of Power Transformers for Study and Mitigation of Effects of GICs

    Author : Seyedali Mousavi; Göran Engdahl; Ebrahim Rahimpour; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; transformer; hysteresis; DC magnetization; GMD; GICs; FEM; reluctance network method; low frequency transients; core losses; winding losses; eddy current losses; transformator; hysteresis; DC; likströmsmagnetisering; GMD; GIC; FEM; reluktansnätverksmodell; lågfrekventa transienter; kärnförluster; lindningsförluster; virvelströmsförluster; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Geomagnetic disturbances that result from solar activities can affect technological systems such as power networks. They may cause DC currents in power networks and saturation of the core in power transformers that leads to destruction in the transformer performance. READ MORE

  5. 5. Modelling approaches for audio frequency power transformers

    Author : Julius Krah; KTH; []
    Keywords : power transformer; audio frequency; loss; hysteresis; eddy currents; skin effect. Leakage inductance;

    Abstract : The development of HVDC converters, local generation andtractions systems increases the demand for power converters.While a lot of studies have been conducted on the powerelectronics, there are still open questions concerning thecontained power transformer that operates at a few kilohertz. READ MORE