POWER SYS. ANALYSIS+DESIGN
6th Edition
ISBN: 9780357700907
Author: Glover
Publisher: INTER CENG
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Textbook Question
Chapter 2, Problem 2.29MCQ
The total instantaneous power absorbed by a three-phase motor (under balanced steady-state conditions) as well as a balanced three-phase impedance load is
(a) A constant (b) A function of time
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What is the main direct cause of reactive power in AC system?A. Resistance of transmission linesB. Inductance and capacitance in the loadsC. Ideal transformer connected in the systemD. Power produced by generator
two synchronous generators are connected in parallel, feeding a load together. the frequency of the first generator in the no-load State is 52 Hz and the slope of the characteristic is 1 MW/Hz. the total power of the load fed by these two generators is 2.5 MW and the power coefficient is 0.6 inductive. by drawing the characteristic curve of the system;a) what is the frequency of the system when the load in question is fed, and how do the two generators share the load between themselvesb) if a load of 0.5 MW is added to the system, find the operating frequency of the new system and the powers given by each generatorc) if a second load of 0.5 MW is connected to the system, the idle operating frequency of the second generator is increased by 0.5 Hz, what happens to the operating frequency of the system and the power values given by the generators
8 = 0
Q1: What does happen if we change two currents?
Q2: What does happen if we have a three-phase four poles machine?
a
Q3: What does happen if we have a two-phase two poles machine?
Q4: What does happen if we apply a capacitance in phase b and then use same
voltage for both phase.
Dr. Ali K....p. . --
Chapter 2 Solutions
POWER SYS. ANALYSIS+DESIGN
Ch. 2 - The rms value of v(t)=Vmaxcos(t+) is given by a....Ch. 2 - If the rms phasor of a voltage is given by V=12060...Ch. 2 - If a phasor representation of a current is given...Ch. 2 - Prob. 2.4MCQCh. 2 - Prob. 2.5MCQCh. 2 - Prob. 2.6MCQCh. 2 - Prob. 2.7MCQCh. 2 - Prob. 2.8MCQCh. 2 - Prob. 2.9MCQCh. 2 - The average value of a double-frequency sinusoid,...
Ch. 2 - The power factor for an inductive circuit (R-L...Ch. 2 - The power factor for a capacitive circuit (R-C...Ch. 2 - Prob. 2.13MCQCh. 2 - The instantaneous power absorbed by the load in a...Ch. 2 - Prob. 2.15MCQCh. 2 - With generator conyention, where the current...Ch. 2 - Consider the load convention that is used for the...Ch. 2 - Prob. 2.18MCQCh. 2 - The admittance of the impedance j12 is given by...Ch. 2 - Consider Figure 2.9 of the text, Let the nodal...Ch. 2 - The three-phase source line-to-neutral voltages...Ch. 2 - In a balanced three-phase Y-connected system with...Ch. 2 - In a balanced system, the phasor sum of the...Ch. 2 - Consider a three-phase Y-connected source feeding...Ch. 2 - For a balanced- load supplied by a balanced...Ch. 2 - A balanced -load can be converted to an...Ch. 2 - When working with balanced three-phase circuits,...Ch. 2 - The total instantaneous power delivered by a...Ch. 2 - The total instantaneous power absorbed by a...Ch. 2 - Under balanced operating conditions, consider the...Ch. 2 - One advantage of balanced three-phase systems over...Ch. 2 - While the instantaneous electric power delivered...Ch. 2 - Given the complex numbers A1=630 and A2=4+j5, (a)...Ch. 2 - Convert the following instantaneous currents to...Ch. 2 - The instantaneous voltage across a circuit element...Ch. 2 - For the single-phase circuit shown in Figure...Ch. 2 - A 60Hz, single-phase source with V=27730 volts is...Ch. 2 - (a) Transform v(t)=75cos(377t15) to phasor form....Ch. 2 - Let a 100V sinusoidal source be connected to a...Ch. 2 - Consider the circuit shown in Figure 2.23 in time...Ch. 2 - For the circuit shown in Figure 2.24, compute the...Ch. 2 - For the circuit element of Problem 2.3, calculate...Ch. 2 - Prob. 2.11PCh. 2 - The voltage v(t)=359.3cos(t)volts is applied to a...Ch. 2 - Prob. 2.13PCh. 2 - A single-phase source is applied to a...Ch. 2 - Let a voltage source v(t)=4cos(t+60) be connected...Ch. 2 - A single-phase, 120V(rms),60Hz source supplies...Ch. 2 - Consider a load impedance of Z=jwL connected to a...Ch. 2 - Let a series RLC network be connected to a source...Ch. 2 - Consider a single-phase load with an applied...Ch. 2 - A circuit consists of two impedances, Z1=2030 and...Ch. 2 - An industrial plant consisting primarily of...Ch. 2 - The real power delivered by a source to two...Ch. 2 - A single-phase source has a terminal voltage...Ch. 2 - A source supplies power to the following three...Ch. 2 - Consider the series RLC circuit of Problem 2.7 and...Ch. 2 - A small manufacturing plant is located 2 km down a...Ch. 2 - An industrial load consisting of a bank of...Ch. 2 - Three loads are connected in parallel across a...Ch. 2 - Prob. 2.29PCh. 2 - Figure 2.26 shows three loads connected in...Ch. 2 - Consider two interconnected voltage sources...Ch. 2 - Prob. 2.35PCh. 2 - Prob. 2.36PCh. 2 - Prob. 2.37PCh. 2 - Prob. 2.38PCh. 2 - Prob. 2.39PCh. 2 - A balanced three-phase 240-V source supplies a...Ch. 2 - Prob. 2.41PCh. 2 - A balanced -connected impedance load with (12+j9)...Ch. 2 - A three-phase line, which has an impedance of...Ch. 2 - Two balanced three-phase loads that are connected...Ch. 2 - Two balanced Y-connected loads, one drawing 10 kW...Ch. 2 - Three identical impedances Z=3030 are connected in...Ch. 2 - Two three-phase generators supply a three-phase...Ch. 2 - Prob. 2.48PCh. 2 - Figure 2.33 gives the general -Y transformation....Ch. 2 - Consider the balanced three-phase system shown in...Ch. 2 - A three-phase line with an impedance of...Ch. 2 - A balanced three-phase load is connected to a...Ch. 2 - What is a microgrid?Ch. 2 - What are the benefits of microgrids?Ch. 2 - Prob. CCSQCh. 2 - Prob. DCSQ
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- Real Power Versus Voltage curve may be used to assess the a.Steady state voltage stability b.Loading of that particular AC Generator c.Dynamic voltage stability d.Complete Voltage stability 2- kinetic energy stored in the rotor of a synchronous alternator is given by a.G * H * w b.m * a c.0.5*m*v*v d.S * Harrow_forwardA synchronous generator has been synchronized to an infinite grid of 13.8 kV and 60 Hz. The generator prime mover C/C is such that the no-load frequency is 62.5 Hz and the power slope is 1 MW/Hz. The AVR C/C (The reactive power against the terminal voltage C/C) is such that the zero reactive power voltage is 14.6 kV, while the slope is 0.4 MVAR/kV. Calculate: (a) the kVA loading of the generator and its power factor. (b) the settings of the prime mover and AVR such that the generator delivers 3 MW at 0.85 lagging power factor.arrow_forward(a) For the system shown in figure find steady state error for (i) Unit step input 10 (ii) Unit Ramp input B)arrow_forward
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