Search for dissertations about: "core magnetization"

Showing result 1 - 5 of 26 swedish dissertations containing the words core magnetization.

2. 1. 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

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

   Author : Seyed Ali Mousavi; Göran Engdahl; S. V. Kulkarni; KTH; []
   Keywords : 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

5. 3. Effect of Dielectric and Magnetic Material Characteristics on Frequency Response of Power Transformers

   Author : Nilanga Abeywickrama; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency response analysis; dielectric insulation; Complex permeability; core magnetization; finite element method; transformer diagnosis.; high frequency modelling; magnetic viscosity; silicon steel;

   Abstract : Frequency response analysis (FRA) technique has become increasingly popular for the assessment of mechanicalintegrity in power transformers. This method is based on the fact that the shape of the frequency response at higher frequencies is uniquely determined by the geometrical construction of the transformer. READ MORE

6. 4. 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

7. 5. Design of Powder Core Motors

   Author : Avo Reinap; Industriell elektroteknik och automation; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; claw-pole motor; Soft magnetic composite; Electrical engineering; 3D finite element analysis; Elektroteknik;

   Abstract : The goal of the study presented in this thesis is to evaluate the advantages and drawbacks of using powder technology in the design of the iron core of small claw-pole electric motors. The use of soft magnetic composites (SMC) and compaction technology allows the creation of complex 3D iron cores. READ MORE