Sökning: "Power transformer"

Visar resultat 11 - 15 av 78 avhandlingar innehållade orden Power transformer.

1. 11. Modelling approaches for audio frequency power transformers

   Författare :Julius Krah; KTH; []
   Nyckelord :power transformer; audio frequency; loss; hysteresis; eddy currents; skin effect. Leakage inductance;

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

3. 12. On Waveform Distortion in Modern Low-Voltage Installations with Multiple Nonlinear Devices

   Författare :Tatiano Busatto; Math Bollen; Xiongfei Wang; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; power quality; power system harmonics; power electronics; nonlinear systems; Electric Power Engineering; Elkraftteknik;

   Sammanfattning : The continuing society quest for more comfort combined with the need to minimize global environmental impacts is constantly introducing new technologies into our daily lives. Among the recent developments, the advances in energy-efficient lighting and renewable energy technologies have enabled a maturity level in cleaner electricity production and efficient use of energy. LÄS MER

4. 13. On feature extraction of voltage disturbance signals

   Författare :Emmanouil Styvaktakis; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spectrum estimation; power quality; capacitor switching; transformer saturation; voltage dips; fault location; power sustem monitoring; induction motors; short time Fourier transform; power sustem faults;

   Sammanfattning : .... LÄS MER

5. 14. 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

7. 15. Control of Dynamically Assisted Phase-shifting Transformers

   Författare :Nicklas Johansson; Hans-Peter Nee; Olof Samuelsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Thyristor Controlled Series Capacitor; Thyristor Switched Series Capacitor; Controlled Series Compensator; Dynamic Power Flow Controller; Phase-Shifting Transformer; Power Oscillation Damping; Transient Stability; Power Flow Control; Adaptive Control; Electric power engineering; Elkraftteknik;

   Sammanfattning : In this thesis, controllers for power oscillation damping, transient stability improvement and power flow control by means of a Controlled Series Compensator (CSC) and and a Dynamic Power Flow Controller (DPFC) are proposed. These devices belong to the group of power system components referred to as Flexible AC Transmission System (FACTS) devices. LÄS MER