Search for dissertations about: "current transformer"

Showing result 1 - 5 of 41 swedish dissertations containing the words current transformer.

  2. 1. Aspects on measuring electrical current utilizing magnetic zero-flux technique

    Author : Maria Hammarqvist; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Current Transformer; AC Current; Frequency Response; Measurement Uncertainty; Traceability; Zero-Flux Measurement Technique; Zero-Flux;

    Abstract : The utilization of high accuracy measurements of electrical quantities is a prerequisite for the development of modern society. Generally, measurements serve different purposes and hence the criteria for the measurement equipment and method are different. READ MORE

  4. 2. DC-DC Converters - Dynamic Model Design and Experimental Verification

    Author : Bengt Johansson; Industriell elektroteknik och automation; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; robotics; buck; dc-dc converter; modeling; audio susceptibility; current-mode control; load current; gain scheduling; current transformer; experimental verification; Electronics and Electrical technology; Automation; Elektronik och elektroteknik; Elektroteknik; Electrical engineering; reglerteknik; robotteknik; Automatiska system; control engineering;

    Abstract : To obtain high performance control of a dc-dc converter, a good model of the converter is needed. The load usually affects the dynamics and one way to take this into consideration is to regard the load as a part of the converter. The load is often the most variable part of this system. READ MORE

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

    Author : Seyedali Mousavi; Göran Engdahl; Ebrahim Rahimpour; KTH; []
    Keywords : 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

  6. 4. Electromagnetic transformer modelling including the ferromagnetic core

    Author : David Ribbenfjärd; Göran Engdahl; David Jiles; KTH; []
    Keywords : 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

  7. 5. On methods of measuring magnetic properties of power transformers

    Author : Claes Carrander; Göran Engdahl; Anders Bergqvist; KTH; []
    Keywords : 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