Search for dissertations about: "transient overvoltage"

Showing result 1 - 5 of 8 swedish dissertations containing the words transient overvoltage.

2. 1. Run-Up Transient Analysis for Salient Pole Wound Field Synchronous Motors : Field winding and power electronics implications for a smoother and cooler asynchronous start

   Author : Roberto Felicetti; Urban Lundin; Andreas Binder; Uppsala universitet; []
   Keywords : apparent resistance; cable modeling; current control; transmission line model; eddy currents; field winding; frequency analysis response; Fourier Transform; impedance mismatch; main inductance; overvoltage; parasitic capacitance; partial discharge; quality factor; ringing; slew rate; stray inductance; voltage gradient; winding resonance frequency; asynchronous start; run-up; torque ripple; reluctance torque; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Abstract : Salient Pole Wound Field Synchronous Machines have better efficiency at full load than asynchronous machines of the same capability. Moreover, where asynchronous machines need inherently to draw a magnetizing current from the grid, Salient Pole Wound Field Synchronous Machines can work efficiently at unity power factor. READ MORE

4. 2. Analysis of High-Frequency Electrical Transients in Offshore Wind Parks

   Author : Tarik Abdulahovic; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; restrikes; very fast transient; surge protection; surge; voltage escalation; transient overvoltage; prestrikes; breaker;

   Abstract : In this thesis, a study of high frequency electromagnetic transient phenomena is performed. Models of various components needed for simulations of high frequency transients, such as transformers, cables and breakers are developed. READ MORE

5. 3. Analysis of High-Frequency Electrical Transients in Offshore Wind Parks

   Author : Tarik Abdulahovic; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; very fast transient; surge protection; surge; transient overvoltage; restrikes; prestrikes; breaker; voltage escalation;

   Abstract : In this thesis, a study of high frequency electromagnetic transient phenomena is performed. Models of various components needed for simulations of high frequency transients, such as for transformers, cables and breakers are developed. READ MORE

6. 4. High Frequency Model of Electrified Railway Propulsion System for EMC Analysis

   Author : Kelin Jia; Rajeev Thottappillil; Hans Bängtsson; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electromagnetic compatibility; railway; propulsion system; multitransmission line; ac motor modeling; vector fitting; fast transient;

   Abstract : A model of the electrified railway propulsion system working in a wide frequency range is studied in this thesis. The high frequency modeling is the first stage to study and predict the Electromagnetic compatibility (EMC) problems in the electrified railway propulsion system, which are safety and reliability issues of high concern. READ MORE

7. 5. Characteristic of Surge Transfer Through Transformers : Study of Conventional Distribution Transformer and XLPE Cable Winding Transformer (Dryformer)

   Author : Mighanda Manyahi; Vladmiir Rakov; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; Physics; Fysik; Electricity; Esp The Study Of Transients and Discharges; elektricitetslära; ssk studiet av transienter och urladdning;

   Abstract : Wide spread application and dependence on microelectronics based equipment in modern society has necessitated the study of power supply quality problems in low voltage power installations. In spite of improvements in surge protection, sensitive equipment connected to low-voltage side of distribution transformer has continued to fail due to transient voltages that are transferred through distribution transformer from high voltage circuits. READ MORE