Experimental study of impedance characteristics in pulsed electrical discharges
Other Title(s)
دراسة تجريبية لخصائص الممانعة للتفريغ الكهربائي النبضي
Dissertant
Thesis advisor
Comitee Members
al-Amidy, Dhia H.
Suhayl, Abd Allah Muhsin
Khamis, Rad Azzawi
Husayn, Ali Abd al-Karim
Iltaif, Abd al-Husayn Khudayr
University
University of Baghdad
Faculty
College of Science
Department
Department of Physics
University Country
Iraq
Degree
Ph.D.
Degree Date
2011
English Abstract
A number of pulsed experiments has been carried out using a high-voltage circuit containing R, L and C in certain arrangements.
Three configurations (spherical, rod-sphere and cylindrically-tipped) of the spark gap electrodes, which were made of either steel or copper, have been used as a high-current switch operated by a voltage of up to 8 kV and triggered in both self- and a third-electrode modes.
Current measurements are carried out using both currentviewing resistors and Rogowski coils designed and constructed for this purpose.
Typical current waveforms have shown obvious dominating inductance effect of the circuit components in an underdamped oscillation.
The behavior of the circuit impedance is studied by recording both pulsed current peaks and charging voltages when currents of up to 4.5 kA are recorded.
The duration of these current pulses are found to extend between 0.1 μs and 0.3μs depending on the values of the circuit components as well as the spacing of the spark gap electrodes along which the plasma propagates with certain speeds of an average value of 5.6 m ms-1 at atmospheric pressure.
Over the whole range of experimental conditions, the average nominal impedance values ranged between 2 Ω and 30 Ω depending on the gap and circuit parameters.
Typical damage patterns were observed in the spherical electrodes with average diameters of up to 8.3 mm on the high voltage electrode and 10.5 mm on the grounded sphere resulting from accumulative discharges and power dissipation within the gap.
Results of the three spark gap configuration were compared with each other to establish an optimum conditions and parameters, which were capable of imposing such features on all experiments.The application of an external longitudinal magnetic field (27G) on the cylindrically-tipped electrodes showed a slight change in the discharge voltage and an alteration in the discharge current density due to physical effects including lateral diffusion of electrons and their energy over successive collisions.
Main Subjects
No. of Pages
140
Table of Contents
Table of contents.
Abstract.
Abstract in Arabic.
Chapter One : Introduction.
Chapter Two : Diagnostics.
Chapter Three : Pulsed electrical discharge experiments.
Chapter Four : Results analysis and discussion.
References.
American Psychological Association (APA)
al-Rashidi, Ala Fadil Ahmad. (2011). Experimental study of impedance characteristics in pulsed electrical discharges. (Master's theses Theses and Dissertations Master). University of Baghdad, Iraq
https://search.emarefa.net/detail/BIM-606165
Modern Language Association (MLA)
al-Rashidi, Ala Fadil Ahmad. Experimental study of impedance characteristics in pulsed electrical discharges. (Master's theses Theses and Dissertations Master). University of Baghdad. (2011).
https://search.emarefa.net/detail/BIM-606165
American Medical Association (AMA)
al-Rashidi, Ala Fadil Ahmad. (2011). Experimental study of impedance characteristics in pulsed electrical discharges. (Master's theses Theses and Dissertations Master). University of Baghdad, Iraq
https://search.emarefa.net/detail/BIM-606165
Language
English
Data Type
Arab Theses
Record ID
BIM-606165