5. A 240-V rms 60-Hz source supplies a parallel combination of a 5-kW heater and a 30-kVA induction motor whose power factor is 0.82. Determine: (a) the system apparent power (b) the system reactive power (c) the kVA rating of a capacitor required to adjust the system power factor to 0.9 lagging (d) the value of the capacitor required.

5. A 240-V rms 60-Hz source supplies a parallel combination of a 5-kW heater and a 30-kVA induction motor whose power factor is 0.82. Determine: (a) the system apparent power (b) the system reactive power (c) the kVA rating of a capacitor required to adjust the system power factor to 0.9 lagging (d) the value of the capacitor required.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.24P: A source supplies power to the following three loads connected in parallel: (1) a lighting load...

See similar textbooks

Similar questions

A source supplies power to the following three loads connected in parallel: (1) a lighting load drawing 10kW. (2) an induction motor drawing 10kVA at 0.90 power factor lagging, and (3) a synchronous motor operating at 10hp,85 effIciency and 0.95 power factor leading (1hp=0.746kW). Determine the real, reactive, and apparent power delivered by the source. Also, draw the source power triangle.
A single-phase, 120V(rms),60Hz source supplies power to a series R-L circuit consisting of R=10 and L=40mH. (a) Determine the power factor of the circuit and state whether it is lagging or leading. (b) Determine the real and reactive power absorbed by the load. (c) Calculate the peak magnetic energy Wint stored in the inductor by using the expression Wint=L(Irms)2 and check whether the reactive power Q=Wint is satisfied. (Note: The instantaneous magnetic energy storage fluctuates between zero and the peak energy. This energy must be sent twice each cycle to the load from the source by means of reactive power flows.)
1. A motor load consists of a resistance of 6 Ohms in series with an inductance of 12 mH. Assume 120Vac, 60 Hz supply. a. What is the complex impedance of the load? b. What is the ac current through this load? c. What is theta, the angle between voltage and current through this load? d. What is the power factor? e. What capacitance should be added in parallel with this load to correct the power factor to 1? f. What is the current from the supply when the power factor is corrected?
A 240 rms 60 Hz source supplies a parallel combination of a 4.5-kW heater and a 27-kVA inductor motor whose power factor is 0.82. Determine the kVA rating of the capacitor required to adjust the system power factor to 0.9 lagging and the value of the capacitor required?
A 240 kVA synchronous motor of rated apparent power consumes 95 kW of active power of the power grid. And it is possible to adjust it so that by working with this same active power, it compensates the power factor by providing reactive power (i.e., appearing with a capacitive component). How can you get this? What is the maximum reactive power that it can provide?
A drilling machine is driven by a single-phase induction machine connected to a 110 V RMS supply. Assuming that the machining operation requires 1 kW, that the tool machine has 90 percent efficiency, and that the supply current is 14 A RMS with a power factor of 0.8. Find the AC machine efficiency.
A drilling machine is driven by a single-phaseinduction machine connected to a 110-V rms supply.Assume that the machining operation requires 1 kW,that the tool machine has 90 percent efficiency, andthat the supply current is 14 A rms with a power factorof 0.8. Find the AC machine efficiency.
A 400-V, 3-phase induction motor load takes 900 kVA at a power factor of 0.707. Calculate the KVA rating of the capacitor bank to raise the resultant power factor of the installation of 0.866 lagging. Find also the resultant power factor when the capacitors are in circuit and the motor load has fallen to 300 kVA at 0.5 power factor.
A series circuit consisting of a resistor that dissipates 640watts, a coil and an ideal capacitor is connected across a 220volts, 60Hz power supply. The current drawn by the load is 8 amperes. The voltage across the coil is 150 volts and its power factor is 0.8 lagging. Determine: a. the resistance of the resistor (10 Ohms)b. the resistance and the inductance of the coil ( 15 Ohms, 29.8416 mH)c. the voltage across the capacitor (181.6515 V)d. the capacitance of the capacitor (116.8207 μF)
A 25 kVA, 240 V single phase source supply the rated power at the rated voltage to a motor at 0.8 power factor lagging. Find the capacitor bank in order to improve the power factor to 0.9 lagging connected to a motor.a. Calculate the real power, reactive power and current before capacitor bank is connected? b. Calculate the power and reactive power after capacitor bank is connected? c.What is kVA rating of capacitor bank QC?
A single-phase alternator connected to 6,600-V bus-bars has a synchronous impedance of 10Ω and a resistance of 1 Ω. If its excitation is such that on open circuit the p.d. would be 5000 V, calculate the maximum load the machine can supply to the external circuit before dropping out of step and the corresponding armature current and p.f. [2864 kW, 787 A, 0.551]
A 40 kW induction motor, with a lagging power factor of 0.76, is supplied by a 120 V rms 60 Hz sinusoidal voltage source. Find the capacitance needed in parallel with the motor to raise the power factor to: (a) 0.9 lagging, and (b) 1.0.