Sökning: "reluctance network method."

Hittade 5 avhandlingar innehållade orden reluctance network method..

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

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

   Sammanfattning : 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. LÄS MER

3. 2. An FRA Transformer Model with Application on Time Domain Reflectometry

   Författare :Hanif Tavakoli; Göran Engdahl; Jonas Ekman; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; complex permeability; lumped circuit model; frequency response analysis; time domain reflectometry; high frequency modeling; transformer diagnosis; reluctance network method.;

   Sammanfattning : Frequency response analysis (FRA) is a frequency-domain method which is used to detect mechanical faults in transformers. The frequency response of a transformer is determined by its geometry and material properties, and it can be considered as the transformer’s fingerprint. LÄS MER

4. 3. 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

5. 4. Dimensioning Tools of MEA Actuator Systems, Including Modeling, Analysis and Technology Comparison

   Författare :Mohsen Torabzadeh-Tari; Göran Engdahl; Hans Bernhoff; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dimensioning tools; MEA; More Electric Aircraft; EMA; Electro Mechanical Actuator; EM; Electrical Machine; Converter; Inverter; Finite Element Method; FEM; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Sammanfattning : Aircraft design is an example of complex engineering where dimensioning tools can be valuable for the designers and decision makers in the early stage of the development process. These tools can be in form of a database over key numbers for different components or technologies. One of the critical parts of an aircraft is the actuator system. LÄS MER

7. 5. Byggbranschens innovationsbenägenhet : En studie om den svenska byggbranschens inställning till innovationer och branschens beredskapatt hantera innovationsfrågor

   Författare :Sune Björklöf; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Building sector; Dissemination of innovation; Innovation; Qualitative method; Socio Cultural tradition; Technical innovation;

   Sammanfattning : The attitude of the building sector towards innovation and its intellectual and organizational preparedness for dealing with the issues of innovation is the aim of this study. The core question can be formulated as follows: Why does a building company accept certain innovations but not others? The fundamental ideas of the study are rooted in the central European tradition of the historico-qualitiative school of thought. LÄS MER