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The following parameters are based on a preliminary line design: per unit
A three-phase power of 700 MW is to be transmitted to a substation located 315 km from the source of power. (a) Determine a nominal voltage level for the three-phase transmission line, based on the practical line-loadability equation. (b) For the voltage level obtained in part (a), determine the theoretical maximum power that can be transferred by the line.
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Power System Analysis and Design (MindTap Course List)
- In the medium-length power transmission line model given below, since the end-of-line voltage value of the nominal-T equivalent circuit is 154 kv, find the voltage regulation value for this line and draw the phasor diagram.arrow_forwardCharacteristics of 165 kV, 150 MVA, 50 Hz 3-phase 100 km transmission linevalues are given below. r=0.103ohm/ kmx=0.525ohm/ kmy=3.3x10^-6 S/ km (a) Calculate the constants A and B for the equivalent circuit of this transmission line,(b) Load lagging power factor of 0.9 when the line is running at nominal (tag) value.if so, find the production side voltage. lesson: Power system analysesarrow_forwardQ1: A 3-phase of sequence ABC transmission line has a conductors of cross section area (82 mm?) and a diameter of (1 cm) as shown in figure below. Delivers a load of 15 MW at 30 kV and power factor of 0.78. Determine the efficiency and voltage regulation of the line. If the line length (65km). The line is completely transposed. For the copper p = 1/58 per meter length. 3 m 4 m 6 m 4 3 marrow_forward
- In short transmission line calculations, the effects of the line capacitance are neglected because such lines have smaller lengths and transmit power at relatively low voltages (< 20 kV). Select one: a. True O b. False O c. None of the abovearrow_forwardConsider the following statements: Surge impedance loading of a transmission line can be increased by 1. increasing its voltage level 2. addition of lumped inductance in parallel 3. addition of lumped capacitance in series 4. reducing the length of the line Which of these statements are correct? (a) 1 and 3 (b) 1 and 4 (c) 2 and 4 (d) 3 and 4arrow_forwardThe equivalent circuit of a single phase short transmission line is shown in Figure Q4 (b). Here, the total line resistance and inductance are shown as lumped instead of being distributed. i) Sketch the phasor diagram and assess with by labeling the details for the A.C. series circuit shown in Figure Q4 (b) for the lagging power factor at load point (Vn). ii) Summarize, the impact of voltage regulation and efficiency, if the line resistance and line increases are doubled Figure Q4(b). R XL Vs Vn Figure Q4(b) Loadarrow_forward
- 1) A 60-Hz, ...-km, three-phase overhead transmission line has a series impedance z = 0.8431L79.04 ohm/km and a shunt admittance y = 5.105 × 106 L90 S/km. The load at the receiving end is 125 MW at unity power factor and at 215 KVLL. Determine the voltage, current, real and reactive power at the sending end and the percent voltage regulation of the line for nominal pi network. (Please determine the length of the transmission line within the specified limits: 150-220 km. By considering the length value you determined yourself, solve the question.)arrow_forwardWhich Transmission Line Parameter is neglected or ignored in most classifications of Transmission Line Equivalent Circuits? A. The Line Inductance B. The Line Resistance C. The Shunt Conductance D. The Shunt Capacitancearrow_forward(a) A three phase transposed transmission tower comprises of three-bundled conductor and double-circuit configured in vertical position as shown in Figure 2. Each sub-conductor in each circuit and each phase is an ACSR type, size 477,000 cmil and stranding 26/7. Given the GMR of each sub-conductor is 0.8809 cm and diameter is 2.1793 cm, analyze: i. Inductance in mH/km ii. Capacitance in µF/km 0.75m 7.5m b' 4m 4m 45cm Figure 2arrow_forward
- iv. For a long high voltage transmission line with light loading : (a) The voltage is generally high due to reactive power generated by the line. (b) The voltage is generally high due to the light loading. (c) The voltage is generally high due to high reactive power generated and the low reactive power consumed by the line.arrow_forwardA 3 phase, 50 HZ, transmission line represented by TI-model and having the following parameters, A= 0.95L 1° and B = 100L 80°. The line supplies a full load of 80 MW at 220 KV and 0.8 lagging power factor. Determine the following (w a. The elements of the tra. ssion line matrix C and D. b. The values of the line parameters R, L, Rsh and Csh- c. The sending end complex power and power factor. d. The voltage regulation. e. The equivalent transmission line matrix if another line with parameters Z = 7+j70 O/phase and Y = j0.00 S/nhase is connected in parallel with the existing line. h 4 decimal places):arrow_forwardi. Some reasons for adopting high transmission line voltages are to improve ------and the enhancement of. ii. The per phase power transmitted under surge impedance loading of a transmission line is given by: iii. Power transmission lines are limited in their power handling capability by the andarrow_forward
- Power System Analysis and Design (MindTap Course ...Electrical EngineeringISBN:9781305632134Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. SarmaPublisher:Cengage Learning