SKEE2413 Final Exams 201320142.pdf - -2SKEE 2413 Q1(a Explain the classification of transmission line based on their length and the parameters

# SKEE2413 Final Exams 201320142.pdf - -2SKEE 2413 Q1(a...

This preview shows page 1 - 3 out of 5 pages.

-2- SKEE 2413 Q1. (a) Explain the classification of transmission line based on their length and the parameters considered to represent the model. [7 Marks] (b) A hydroelectric power station is supplied from a reservoir having an area of 50 km 2 and a head of 50 m. If overall efficiency of the station is 60%, find the rate at which the water level will fall in mm/hour when the station is generating 30000 kW. Note: Density of water is 1000 kg/m 3 and gravitational constant is 9.81 m/s 2 . [7 marks] (c) A three phase 50 Hz transmission line with a length of 180 km is connected to a 3 MW load with 0.9 lagging power factor at 33 kV. The line conductor has series parameter of 0.2 + j0.5 Ω /km. Given the sending voltage and the sending current, V s = 22, 973.61 10.17 o and I s = 52.08 -11.53 o at 24.6% of voltage regulation. Calculate using nominal- π model, i. the shunt parameter of the transmission line [8 Marks] ii. the efficiency of the transmission line [3 marks] -3- SKEE 2413 Q2. (a) State what do you understand by Lenz Law. [3 marks] (b) Explain how practical transformer are usually being rated.  #### You've reached the end of your free preview.

Want to read all 5 pages?

• Fall '20
• Electric motor, Electric power, 6 hours, 5 hours, 0.1 mm
• • •  