1.1 (3 marks) A single-phase power system consists of a 480 volt 60 Hz generator supplying a load of 4 + j 3 ohms through a transmission line whose impedance is 0.18 + j 0.24 ohm. The generator impedance may be neglected.
1.1.1 Determine the transmission loss (power loss in the transmission line resistance. (1 mark)
1.1.2 Redo the 1.1.1 when the following is done to the power system. The generated voltage is stepped up ten times by using an ideal transformer of turns-ratio 1:10. At the load end the reverse is done i.e a step-down transformer with turns-ratio of 10:1 is used before connecting the load. (1 mark)
Redo 1.1.2 using per unit quantities. You may select 50 kVA and 480 volts as bases. (1 mark)
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Here, first with actual line and load impedances, line current is calculated. The losses in resistance of transmission line is calculated. After this by including transformers, impedances on one side is calculated. Then line current and losses in line resistance is calculated. At the end by using per unit system, line losses are calculated.
1.1 (3 marks) A single-phase power system consists of a 480 volt 60 Hz generator supplying...
1. A single-phase power system consists of a 480-V 60-Hz generator supplying a load of Zload = 4 + j3 2 through a transmission line of impedance Zline = 0.18 + 0.24 2. (a) (i) If the power system is exactly as shown in Fig. P3.1, calculate the line current voltage at the load. (ii) Calculate the transmission line losses. (b) Suppose a 1:10 step-up transformer is placed at the generator end of the transmission line and 10:1 step-down transformer...
A single-phase 100-kVA, 2400/240-volt, 60-Hz distribution transformer is used as a step-down transformer. The load, which is connected to the 240-volt secondary winding, absorbs 80 kVA at 0.8 power factor lagging and is at 230 volts. Assuming an ideal transformer, calculate the following: a) primary voltage. b) load impedance. c) load impedance referred to the primary. d) the real and reactive power supplied to the primary winding
3.4 A single-phase 100-kVA, 2400/240-volt, 60-Hz distribution transformer is used as a step-down transformer. The load, which is connected to the 240-volt secondary wind- ing, absorbs 80 kVA at 0.8 power factor lagging and is at 230 volts. Assuming an ideal transformer, calculate the following: (a) primary voltage, (b) load impedance, (c) load impedance referred to the primary, and (d) the real and reactive power sup- plied to the primary winding.
1) A single-phase 50-kVA, 2400/240 volt, 60 Hz distribution transformer is used as a step-down transformer at the load end of a 2400-volt feeder whose series impedance is (1.0+2.0) Ω. The equivalent series impedance of the transformer is (10+j25) Ω referred to the high voltage (primary) side. The transformer is delivering rated load at 0.8 power factor lagging and at rated secondary volitage. Neglect the transformer exciting curent. Using the transtormer raltings as base quantities work this problem in per...
last two digits of student number are 10 Q.3 A single-phase power system is shown in Figure. The power source feeds a load through a transmission line and a IXY (kVA), 20kV/3.8kV transformer. The transformer's series impedance is shown as referred to the LV side. The source voltage is v:(t) = 2Xsin(3141) kV, which delivers 120 kVA at 0.95 power factor lagging to the system. Determine, a. actual voltage drop in the transmission line, (5 marks) b. actual voltage drop...
Problem 1: A single-phase load with a nameplate rating of 4.16kV, 2.5MW, 0.8 pf (lag) is being supplied from a 4.16kV singe-phase generator. There is a 5km transmission line between the generator and the load. The transmission line has an impedance of 0.5 / 60◦ ohms per 1000m. What is the ratio of the voltage at the load to the voltage at the generator terminals? What is the power loss in the transmission line? What is the actual load power?...
1) Figure- generator is producing a line voltage of 480 V, and the line impedance is 0.09 + j0.16 . Load 1 is Y connected, with a phase impedance of 2.5236.87° 0 and load 2 is A connected, with a phase impedance of 54-20° n. shows a three-phase power system with two loads. The A-connected 2 0.09 j0.16 n w Vca= 4802-240° V + Vab = 48020 V Vhc = 480-120° V 0.09 j0.16 0.09 j0.16 Load 1 Load 2...
1. In order to meet an emergency, three single-phase transformers with 12.470/7.200 V are connected in Delta-Wye to form a three-phase transformer which is fed by a 12.470 V transmission line. If the transformer supplies 60 MVA to a load, calculate: (3 marks) a. The turns ratio for each transformer b. The currents in the primary and secondary windings of the transformer c. The primary and secondary transmission line currents 2. A Wye-Delta transformer is connected to a 66 kV...
The circuit below represents a three-phase, 60 Hz, synchronous generator supplying powerto an induction motor. Since the system is balanced, the diagram represents only Phase A of the system. Assume the motor magnetizing reactance, the motor friction loss, core loss, and windage loss are neglected to simplify the circuit. In addition, all losses in the generator are ignored Generator rating: 10.0 MVA and 13.8 kV (line voltage); Motor rating: 9.0 MW output, 4 poles, 60 Hz, R10.9 Ohm and R2...
Consider a simple power system consisting of an ideal voltage source, an ideal step-up transformer, a transmission line, and ideal step-down transformer, and a load. The voltage ofthe source is Vs-480/00V. The impedance of the transmission line is Zline-1H2 Ω, and the impedance of the load is Zload 10+j25 2 (1) Assume that the transformers are not present in the circuit. What is the power factor of the system? What is the load voltage Vi and efficiency of the system?...