(a) Describe The advantages and disadvantages of DC and AC Transmission Systems? ii. 4+1 The advantages...

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(a) Describe The advantages and disadvantages of DC and AC Transmission Systems? ii. 4+1 The advantages of using high transmission voltage? (b) Analyze the expression for volume of conductor material in a single-phase, 3-wire overhead AC system? 1. (c Mllustrate graphically or mathematically that the current in the neutral wire of the single-phase, 3-wire overhead AC system will be zero in case of balanced load? A sub-station supplies power at 11 kV, 0-8 p.f. lagging to a cousumer through a single phase transmission line having total resistance (both go and return) of 0.15 . The voltage drop in the line is 15%. If the same power is to be supplied to the same consumer by two wire d.c. system by a new line having a total resistance of 0-05 and if the allowable voltage drop is 25%, calculate/analyze the d.c. supply voltage? 5. (a) Describe methods of improving string efficiency? 3. (a) The three bus-bar conductors in an outdoor substation are supported by units of post type insulators. Each unit consists of a stack of 3 pin type insulators fixed one on the top of the other. The voltage across the lowest insulator is 13-1 kV and that across the next unit is 11 kV. Calculate/Analyze the bus-bar voltage of the station? 8. 2. (a) Describe The advantages and disadvantages of DC and AC Transmission Systems? ii. 4+1 The advantages of using high transmission voltage? (b) Analyze the expression for volume of conductor material in a single-phase, 3-wire overhead AC system? 1. (c Mllustrate graphically or mathematically that the current in the neutral wire of the single-phase, 3-wire overhead AC system will be zero in case of balanced load? A sub-station supplies power at 11 kV, 0-8 p.f. lagging to a cousumer through a single phase transmission line having total resistance (both go and return) of 0.15 . The voltage drop in the line is 15%. If the same power is to be supplied to the same consumer by two wire d.c. system by a new line having a total resistance of 0-05 and if the allowable voltage drop is 25%, calculate/analyze the d.c. supply voltage? 5. (a) Describe methods of improving string efficiency? 3. (a) The three bus-bar conductors in an outdoor substation are supported by units of post type insulators. Each unit consists of a stack of 3 pin type insulators fixed one on the top of the other. The voltage across the lowest insulator is 13-1 kV and that across the next unit is 11 kV. Calculate/Analyze the bus-bar voltage of the station? 8. 2.

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1 a i Advantages and Disadvantages of DC transmission system Advantages 1 There are two conductors are used in DC transmission while three conductors are required in AC transmission 2 There are no ind... View the full answer