Materials selection process for electrical insulation application was carried out using Cambridge Engineering Selector (CES) program. Melt mixing technique was applied to prepare polyvinyl-chloride- (PVC-) nanofumed silica and nanomontmorillonite clay composites. Surface analysis and particles dispersibility were examined using scanning electron microscope. Dielectrical properties were assessed using Hipot tester. An experimental work for dielectric loss of the nanocomposite materials has been investigated in a frequency range of 10 Hz–50 kHz. The initial results using CES program showed that microparticles of silica and clay can improve electrical insulation properties and modulus of elasticity of PVC. Nano-montmorillonite clay composites were synthesized and characterized. Experimental analyses displayed that trapping properties of matrix are highly modified by the presence of nanofillers. The nanofumed silica and nanoclay particles were dispersed homogenously in PVC up to 10% wt/wt. Dielectric loss tangent constant of PVC-nanoclay composites was decreased successfully from 0.57 to 0.5 at 100 Hz using fillers loading from 1% to 10% wt/wt, respectively. Nano-fumed silica showed a significant influence on the electrical resistivity of PVC by enhancing it up to 1 × 1011 Ohm·m.

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Voltage collapse is an undesired phenomenon that occurs due to voltage instability and is generally associated with weak or stressed system (heavily loaded lines), long lines, radial networks, faults and/or reactive power shortages. Its occurrence is not frequent in developed countries despite their large and complex networks but its frequency is high in Egypt. Voltage collapses are highly catastrophic anytime they occur. On the Egyptian Interconnected Electrical Grid EIEG, the system collapse phenomenon is frequently experienced and often leads to either partial or total system collapse blackout, which greatly impairs the nation's socioeconomic development and industrialization. This high rate is due to the fact that the EIEG is weak, highly stressed, long and radial in nature hence lacking flexibility. The analysis is performed for EIEG power system. Modern advances in technology are changing the way utility industry increase the transmission of power throughout the country. Distributed energy resources are constantly improving their reliability and power capabilities. The model analysis technique is performed for system using the constant load model. The simulation results are Q-V curves on weak voltages by Power World Simulator PWS Software and Matlab Program.

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