Sökning: "eddy currents"
Visar resultat 16 - 20 av 37 avhandlingar innehållade orden eddy currents.
16. Measurement and modelling of unbalanced magnetic pull in hydropower generators
Sammanfattning : Hydropower research is often perceived to be an old and exhausted field of study but with ageing equipment and the need for more intermittent operation caused by an increased share of other renewable energy sources new challenges lie ahead.The main focus of this dissertation are the electromagnetic forces resulting from nonuniform air gap flux, whether it be caused by rotor eccentricity or a faulty field winding. LÄS MER
17. A measurement approach to determination of coating thickness with eddy currents and to a capacitive person detector for robot safety
Sammanfattning : The research presented in this thesis is about coating thickness measurements using eddy currents, and a capacitive detector for detecting humans, for safety in industry.A method for determination of coating thickness of a copper-plated steel wire by measurement of the internal wire impedance, when this is forced by a constant, sinusoidal current, is presented. LÄS MER
18. Inductive measurement of narrow gaps for high precision welding of square butt joints
Sammanfattning : A recent method in aero engine production is to fabricate components from smaller pieces, rather than machining them from large castings. This has made laser beam welding popular, offering high precision with low heat input and distortion, but also high productivity. LÄS MER
19. Electromagnetic Modelling of Power Transformers for Study and Mitigation of Effects of GICs
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
20. An inductive gap measurement method for square butt joints
Sammanfattning : A recent method in aero engine production is to fabricate components from smaller pieces, rather than machining them from large castings. This has made laser beam welding popular, offering high precision with low heat input and distortion, but also high productivity. LÄS MER