Search for dissertations about: "core losses"

Showing result 1 - 5 of 76 swedish dissertations containing the words core losses.

2. 1. 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

4. 2. Temperature and heat losses simulation in core and winding of a power transformer

   Author : Kourosh Mousavi Takami; Mahmoudi Jafar; Lennart Harnefors; Mälardalens högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electric Power Transformer; Losses; Simulation; Temperature; Calculation; Electric power engineering; Elkraftteknik; elektronik; Electronics;

   Abstract : Simulering av temperatur och värmeförluster i kärna och lindning för en högspänningstransformator “... Ett ljus som lyser dubbelt så starkt, varar hälften så länge …”, i analogi med ljuset så kan transformatorer köras med överlast inom vissa gränser, men med följden att livslängden blir kortare. READ MORE

5. 3. 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

6. 4. 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

7. 5. A lumped element transformer model including core losses and winding impedances

   Author : David Ribbenfjärd; Göran Engdahl; Arvid Broddefalk; KTH; []
   Keywords : 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;

   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