Sökning: "hysteresis losses"

Visar resultat 1 - 5 av 21 avhandlingar innehållade orden hysteresis losses.

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

    Författare :Seyedali Mousavi; Göran Engdahl; Ebrahim Rahimpour; KTH; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  3. 2. Electromagnetic transformer modelling including the ferromagnetic core

    Författare :David Ribbenfjärd; Göran Engdahl; David Jiles; KTH; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  4. 3. A lumped element transformer model including core losses and winding impedances

    Författare :David Ribbenfjärd; Göran Engdahl; Arvid Broddefalk; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; power transformer; hysteresis; dynamic hysteresis; eddy currents; excess eddy currents; leakage flux; winding model; core model; magnetic measurements; magnetic materials; Electrical engineering; Elektroteknik;

    Sammanfattning : 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. LÄS MER

  5. 4. On magnetic amplifiers in aircraft applications

    Författare :Lars Austrin; Göran Engdahl; Lars Liljestrand; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; magnetic amplifier magamp ; amorphous; power losses; control winding; self-saturating; hysteresis; converter; more electric aircraft MEA ; inverter; power-by-wire; dymola; permanent magnet generator; PM-generator transformer rectifier unit TRU ; constant speed drive CSD ; excess losses or anomalous losses; modeling; simulation; unmanned aerial vehicle UAV ; Electrical engineering; Elektroteknik;

    Sammanfattning : In the process of designing an electric power supply system for an aircraft, parameters like low weight and low losses are important. Reliability, robustness and low cost are other important factors. LÄS MER

  7. 5. Modeling of losses in power transformers from dc to the low kilohertz range

    Författare :Julius Krah; Göran Engdahl; Roland Eriksson; Anthony Moses; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical power technology; power transformer; losses; magnetic hysteresis; magnetic measurement systems; medium frequency; eddy currents; skin effect; thermal diffusion; Elkraftteknik; Electric power engineering; Elkraftteknik;

    Sammanfattning : The development of HVDC converters, local generation and tractions systems increases the demand for power converters. While a lot of studies have been conducted on the power electronics, there are still open questions concerning the contained power transformer that operates at a few kilohertz. LÄS MER