Standard voltages for transmission. Advantage of high voltage transmission. Feeders, distributors & service mains.
sag calculation in conductors a) suspended on level supports b) support at different levels. Effect of wind & ice tension & sag at erection. Stringing chart
Phenomena, expression for disputative & visual critical voltages & corona power loss
Types, potential distribution over a string of suspension insulators. String efficiency & methods of increasing strings efficiency, testing of insulators.
Types, material used, insulation resistance, thermal rating of cables, charging current, grading of cables, capacitance grading & inter sheath grading, testing of cables.
calculation of inductance of single phase, 3phase lines with equilateral & unsymmetrical spacing. Inductance of composite conductor lines. Capacitance-calculation for two wires & three phase lines, capacitance calculation for two wire three-phase line with equilateral & unsymmetrical spacing.
Short tr.-lines, medium tr.-lines, nominal T method, end condenser method, p method and long transmission lines, ABCD constants of transmission lines, Power flow through lines, P-V & Q-V coupling.
radial & ring main systems, ac to dc distribution: calculation for concentrated loads and uniform loading