A 400v symmetrical three phase source with grounded neutral

Question

Problem 1: An overhead line is supported between two towers. The base of Tower A is 185m above sea level and the tower is 25m high. Tower B base is at 200m above sea level and the tower is 35m high. The distance between the towers is 350m. The conductor weight is 32N/m and the tension at the tower is 35kN. At what height above sea level is the lowest point of the conductor, assuming that xW << T_o so that the approximation y = x²W/2T_o may be used.

Problem 2: A 400V symmetrical three phase source with grounded neutral supplies a load comprising three impedances in star formation. The impendence have the following values:

Za = 20Ω

Zb = (12 + j5)Ω

Zc = (3 - j4)Ω

Calculate the total active and reactive power supplied to the load both with and without the load star point grounded.

Problem 3: While on a walk in the countryside, you come across a fallen HV conductor which, due to a protection failure, has not tripped. If the HV system is solidly grounded, explain how the fault current presents a danger to you. Would this danger still be present if the system was arc-suppressed?

Answer 1

By using the formulas and principles of Electrical engineering, solve and provide solution to following questions and please try to describe the whole computation part in a word paper. Question 1: An overhead line is supported between the two towers. The base of Tower A is 185m above the sea level and tower is 25m high. The base of tower B base is at 200m above sea level and the tower is 35m high. The distance between the towers is around 350m. The conductor weight is 32N/m and the tension at tower is 35kN. Determine the height above sea level which is the lowest point of the conductor, supposing that xW << To in such a way the approximation y = x2W/2To might be utilized. Question 2: At the time of walk in the countryside, you come across a fallen HV conductor which, because of a protection failure, has not tripped. If the HV system is firmly grounded, describe how the fault current presents a danger to you. Explain would this danger still be present if the system was arc-suppressed?