الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The performance of the underground distribution system is critically influenced by its installations. In this thesis different installation methods of single-core screened cables buried directly in the ground, with and without armour have been studied. These methods are such as bonding types and different configurations. Single-point bonding and two-point bonding types of the metallic sheath have been presented. The core transposition and core, sheath transposition of nonarmoured single-core cable has been investigated. The transposition of armoured single-core cable using only core and using core, sheath and armour has been investigated. Touching trefoil, trefoil, equilateral, touching flat, flat symmetrical and flat asymmetrical configurations of the single-core cables have been modeled. A model for single-core screened cables has been designed with only inductance consideration or with inductance and capacitance consideration. Mathematical algorithm has been proposed to be applied on two bonding types and different configurations taking into account the cable armour. The procedure takes into account the existence of all three cable sheaths as the return path for the ground-fault current for nonarmoured single-core cables. It also takes into account the existence of all three cable sheaths and all three cable armours as the return path for the ground-fault current for armoured single-core cables. Equivalent series impedance matrices and Equivalent shunt susceptance matrices of armoured and nonarmoured single-core cables under the two bonding types and different configurations have been calculated. Sheath resistance, armour resistance and the clearance between the three single-core cables have been taken into consideration. Based on this mathematical algorithm the calculations have been carried out by a proposed computer program using MATLAB to determine the effect of installation methods on the voltage DROP, sheath current and armour current of the single-core cables along their route. The behavior of the protective relaying under these installation methods have been discussed. Balanced and unbalanced performance of the single-core cables under steady state operation, at constant frequency and under two bonding types and different configurations has been discussed. Cases study has been taken to show how the proposed algorithm can be applied. Some recommendations from this work have been presented.