Fundamentals of Electric Circuits
6th Edition
ISBN: 9780078028229
Author: Charles K Alexander, Matthew Sadiku
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 12, Problem 42P
A balanced three-phase generator delivers 7.2 kW to a wye-connected load with impedance 30 − j40 Ω per phase. Find the line current IL and the line voltage VL.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
a.
Y-Connected
b.
В
100kW
Source
0.9 LAG
80KVA
0.8 LAG
Figure 1
80kW
0.85 LAG
A balanced three-phase load requires 1.8kW and power factor 0.5. If the line voltage at the terminals of the load is 230 V.
the magnitude of line current is:
Select one:
a. 7.82 A
O b. 9.03A
O c. 15.65 A
O d. 4.51 A
Two delta connected loads are connected in parallel and powered by a balanced Y-connectedsource. The smaller of two loads draws 10 kVA at a lagging power factor of 0.75 and the largerdraws 25 kVA at a leading power factor of 0.8. The line voltage is 400 V. Calculate a) The powerfactor at which the source is operating. b) The total power drawn by the two loads. c) The phasecurrent of each load.
Chapter 12 Solutions
Fundamentals of Electric Circuits
Ch. 12.2 - Given that Vbn=22030V, find Van and Vcn, assuming...Ch. 12.3 - A Y-connected balanced three-phase generator with...Ch. 12.4 - One line voltage of a balanced Y-connected source...Ch. 12.5 - A positive-sequence, balanced -connected source...Ch. 12.6 - In a balanced -Y circuit, Vab=44015 and ZY = (12 +...Ch. 12.7 - For the Y-Y circuit in Practice Prob. 12.2,...Ch. 12.7 - Calculate the line current required for a 30-kW...Ch. 12.7 - Assume that the two balanced loads in Fig....Ch. 12.8 - The unbalanced -load of Fig. 12.24 is supplied by...Ch. 12.8 - Find the line currents in the unbalanced...
Ch. 12.9 - Prob. 11PPCh. 12.9 - For the unbalanced circuit in Fig. 12.32, use...Ch. 12.10 - Repeat Example 12.13 for the network in Fig. 12.24...Ch. 12.10 - Let the line voltage VL = 208 V and the wattmeter...Ch. 12.10 - If the load in Fig. 12.35 is delta-connected with...Ch. 12 - What is the phase sequence of a three-phase motor...Ch. 12 - If in an acb phase sequence, , then Vcn is:Ch. 12 - Which of these is not a required condition for a...Ch. 12 - Prob. 4RQCh. 12 - Prob. 5RQCh. 12 - In a Y-Y system, a line voltage of 220 V produces...Ch. 12 - In a - system, a phase voltage of 100 V produces a...Ch. 12 - When a Y-connected load is supplied by voltages in...Ch. 12 - Prob. 9RQCh. 12 - Prob. 10RQCh. 12 - If Vab = 400 V in a balanced Y-connected...Ch. 12 - What is the phase sequence of a balanced...Ch. 12 - Given a balanced Y-connected three-phase generator...Ch. 12 - A three-phase system with abc sequence and VL =...Ch. 12 - For a Y-connected load, the time-domain...Ch. 12 - Using Fig. 12.41, design a problem to help other...Ch. 12 - Obtain the line currents in the three-phase...Ch. 12 - In a balanced three-phase Y-Y system, the source...Ch. 12 - A balanced Y-Y four-wire system has phase voltages...Ch. 12 - For the circuit in Fig. 12.43, determine the...Ch. 12 - In the Y- system shown in Fig. 12.44, the source...Ch. 12 - Using Fig. 12.45, design a problem to help other...Ch. 12 - In the balanced three-phase Y- system in Fig....Ch. 12 - Obtain the line currents in the three-phase...Ch. 12 - The circuit in Fig. 12.48 is excited by a balanced...Ch. 12 - A balanced delta-connected load has a phase...Ch. 12 - A positive sequence wye-connected source where ,...Ch. 12 - If Van = 22060 V in the network of Fig. 12.49,...Ch. 12 - For the - circuit of Fig. 12.50, calculate the...Ch. 12 - Prob. 20PCh. 12 - Three 440-V generators form a delta-connected...Ch. 12 - Find the line currents IaA, IbB, and IcC in the...Ch. 12 - A balanced delta connected source is connected to...Ch. 12 - A balanced delta-connected source has phase...Ch. 12 - In the circuit of Fig. 12.54, if , , , find the...Ch. 12 - Using Fig. 12.55, design a problem to help other...Ch. 12 - A -connected source supplies power to a...Ch. 12 - The line-to-line voltages in a Y-load have a...Ch. 12 - A balanced three-phase Y- system has V rms and Z =...Ch. 12 - In Fig. 12.56, the rms value of the line voltage...Ch. 12 - A balanced delta-connected load is supplied by a...Ch. 12 - Design a problem to help other students better...Ch. 12 - A three-phase source delivers 4.8 kVA to a...Ch. 12 - A balanced wye-connected load with a phase...Ch. 12 - Three equal impedances, 60 + j30 each, are...Ch. 12 - A 4200-V, three-phase transmission line has an...Ch. 12 - The total power measured in a three-phase system...Ch. 12 - Given the circuit in Fig. 12.57 below, find the...Ch. 12 - Find the real power absorbed by the load in Fig....Ch. 12 - For the three-phase circuit in Fig. 12.59, find...Ch. 12 - A balanced delta-connected load draws 5 kW at a...Ch. 12 - A balanced three-phase generator delivers 7.2 kW...Ch. 12 - Refer to Fig. 12.48. Obtain the complex power...Ch. 12 - A three-phase line has an impedance of 1 + j3 per...Ch. 12 - A balanced wye-connected load is connected to the...Ch. 12 - A three-phase load consists of three 100-...Ch. 12 - The following three parallel-connected three-phase...Ch. 12 - A balanced, positive-sequence wye-connected source...Ch. 12 - Each phase load consists of a 20- resistor and a...Ch. 12 - A balanced three-phase source with VL = 240 V rms...Ch. 12 - Consider the wye-delta system shown in Fig. 12.60....Ch. 12 - A four-wire wye-wye circuit has...Ch. 12 - Using Fig. 12.61, design a problem that will help...Ch. 12 - A balanced three-phase Y-source with VP = 880 V...Ch. 12 - A three-phase supply, with the line-to-line...Ch. 12 - Using Fig. 12.63, design a problem to help other...Ch. 12 - Determine the line currents for the three-phase...Ch. 12 - Solve Prob. 12.10 using PSpice or MultiSim. For...Ch. 12 - The source in Fig. 12.65 is balanced and exhibits...Ch. 12 - Use PSpice or MultiSim to determine Io in the...Ch. 12 - Given the circuit in Fig. 12.67, use PSpice or...Ch. 12 - Using Fig. 12.68, design a problem to help other...Ch. 12 - Use PSpice or MultiSim to find currents IaA and...Ch. 12 - For the circuit in Fig. 12.58, use PSpice or...Ch. 12 - A balanced three-phase circuit is shown in Fig....Ch. 12 - A three-phase, four-wire system operating with a...Ch. 12 - As shown in Fig. 12.72, a three-phase four-wire...Ch. 12 - Meter readings for a three-phase wye-connected...Ch. 12 - A certain store contains three balanced...Ch. 12 - The two-wattmeter method gives P1=1200W and...Ch. 12 - In Fig. 12.73, two wattmeters are properly...Ch. 12 - If wattmeters W1 and W2 are properly connected...Ch. 12 - For the circuit displayed in Fig. 12.74, find the...Ch. 12 - Predict the wattmeter readings for the circuit in...Ch. 12 - Prob. 75PCh. 12 - Show that the I2R losses will be higher for a...Ch. 12 - A three-phase generator supplied 10 kVA at a power...Ch. 12 - Prob. 78CPCh. 12 - A balanced three-phase generator has an abc phase...Ch. 12 - A balanced three-phase source furnishes power to...Ch. 12 - A professional center is supplied by a balanced...Ch. 12 - A balanced three-phase system has a distribution...Ch. 12 - A commercially available three-phase inductive...Ch. 12 - Figure 12.76 displays a three-phase...Ch. 12 - Design a three-phase heater with suitable...Ch. 12 - For the single-phase three-wire system in Fig....Ch. 12 - Consider the single-phase three-wire system shown...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, electrical-engineering and related others by exploring similar questions and additional content below.Similar questions
- Three phase power A balanced delta-connected source delivers power to a balanced delta-connected load. The line-to-line voltage at the source is l'i- 173 I'and the load impedance is Za = 30 + j!0 O. jie 2 E 30a 1732120 V 1732-120V jio n Figure 3 a) Find the rmis equivalent line-to-neutral source voltage and the equivatent wye load. b) Find the ms magnitudes of the line currents, the load currents, and the voltages. across the load impedances. c) Find the total power delivered to the load. Assume the line is ideal.: d) What would the power lost in the line if its impedance is v2<45°n. shiearrow_forward5. The figure below shows two star connected loads with three phase power. The voltage source is 120Z0°. The loads are Z₁ = 10 + j4 № and Z₂ = 2 +j3 №. The cables are negligible. Calculate: a) the line and phase current. b) the real power from the source. c) the reactive power of the circuit. Is V N Z₁ Z₁ Z₁ Z₂ Z₂ N N Z₂arrow_forwardA delta connected load of impedances (6 + j9) ohms each is supplied through a line having an impedance of (1 + j2) ohms. The supply voltage is balanced 3-phase, 400 V, 60 Hz mains. Find the total power drawn by the load.arrow_forward
- A 208-V three-phase power system is shown in Figure A-13. It consists of an ideal 208-V Y-connected three-phase generator connected through a three- phase transmission line to a Y-connected load. The transmission line has an impedance of 0.06 + j0.120 per phase, and the load has an impedance of 12 + j9 N per phase. For this simple power system, find The magnitude of the line current I 0.06 N j0.12 N 0.06 N j0.12 n V- 1202-240° Van Z, = 12 + 9 N 12020 208 V Van - 1202-120°( 0.06 N j0.12 narrow_forward2. For the following system shown in the figure, calculate: a. The current through each phase of the load. b. The total real and reactive power of the three-phase load. c. The power factor at the load side. A 220 V 20° 220VL-120° U8 vol 152 I 220 VI20° 9. M.arrow_forwardA negative sequence balanced three-phase Y-connected source supplies power to a balanced, three-p connected load with an impedance of 12 + j9 22/0. The line impedance is 1 +j1 02/0. The line to neutral voltage of the source in the a-phase is 240 V. The current in the c-phase of the load is: Select one: O a. 14.633 A O b. 3748 A O c. 37.48 A O d. 14.633 Aarrow_forward
- Draw a 3-phase wye-connected generator with transmission lines connected to a 3-phase delta-connected load. Assume the lines connecting them have an inductance of j5 per phase. The generated voltages are 120 Vrms with phase 'a' having a phase angle of 0°. The loads are 10 Ohm resistors per phase. When drawing, make sure to label all 3 phases with voltage phasors, line inductances, and load resistances.arrow_forwardZjine 1:10 10:1 VG = 13.84 0° kV Zoad T1 T2 A 13.8-kV, single-phase generator supplies power to a load through a step-up transformer, a transmisson line, and a step-down transformer as in the figure above. Assume the transformers are ideal. The load's impedance is Zload = 200 L 36.87°, and the transmission line's impedance is Zline = 80 L 60° What is the efficiency of the transmission system?arrow_forwardA wye-connected load has an impedance of (4.69 + j1.71) per phase. The load is connected across a 120 V, 3-phase source. Find the line current.arrow_forward
- 2. A voltage applied to a load is V=208420°V and current through load is I=10 &-10° A. Find the following [SO 1] o complex power consumed by load • Is the load inductive or capacitive? o the power factor of the load o the reactive power consumed or generated by the load. o Does the load consume or supply reactive power? 3. A single phase motor draws 20 kVA at 0.70 lagging power factor from a 120 V source. The PUD desires to improve the power factor to 0.9 lagging by connecting a shunt capacitor bank across the terminals of the motor. Determine the size of the capacitor bank in VARS. Calculate the following: [SO 1] a) What are the initial load current, real and reactive powers of the load? b) What are the real and reactive power after adding the capacitor bank? c) What is the kVAr rating of the capacitor bank? (3) d) What is the load current? di) How is the load current affected by the load reactive power?arrow_forwardA three-phase A-connected generator has an inter- nal impedance of 9 + j90 m2/þ. When the load is removed from the generator, the magnitude of the terminal voltage is 13,800 V. The generator feeds a A-connected load through a transmission line with an impedance of 20 + j180 m2/þ. The per-phase impedance of the load is 7.056 + j3.417 N. a) Construct a single-phase equivalent circuit. b) Calculate the magnitude of the line current. c) Calculate the magnitude of the line voltage at the terminals of the load. d) Calculate the magnitude of the line voltage at the terminals of the source.arrow_forwardA positive sequence balanced three-phase Y-connected source supplies power to a balanced, three-phase A- connected load with an impedance of 12 + j9 /0. The line impedance is 1 +j1 0/0. The line to neutral voltage of the source in the a-phase is 240 V. The current in the c-phase of the load is: Select one: O a. 37.48 A O b. 37.48 A O c. None of these O d. 14.63 A TOSHIBAarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Power System Analysis and Design (MindTap Course ...Electrical EngineeringISBN:9781305632134Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. SarmaPublisher:Cengage Learning
Power System Analysis and Design (MindTap Course ...
Electrical Engineering
ISBN:9781305632134
Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma
Publisher:Cengage Learning
What is the Difference Between Single Phase and Three Phase???; Author: Electrician U;https://www.youtube.com/watch?v=FEydcr4wJw0;License: Standard Youtube License