A 220 V d.c. shunt motor having an armature resistance of o.25 Q carries an armature current of 50 A and run at 600 r.p.m. if the flux is reduced by 10% by field regulator, find the speed assuming load torque remains the same

A 220 V d.c. shunt motor having an armature resistance of o.25 Q carries an armature current of 50 A and run at 600 r.p.m. if the flux is reduced by 10% by field regulator, find the speed assuming load torque remains the same

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

See similar textbooks

Similar questions

Electric Machine; Check image, all question there. Let’s consider three phase, Y connected, 220 volt (line to line), 7.5 kW, 55 Hz, four pole IM has the following parameter values in Ω/phase referred to the stator: R1=0.294Ω , R2=0.144 Ω, X1=0.503 Ω, X2=0.209 Ω, Xm=13.25 Ω Determine the following for 0.02 slip. a)Electromechanical Torque(Tmech) Electromechanical power(Pmech) b)Maximum electromechanical torque(Tmax),Corresponding speed(nr,max) c)Electromechanical starting torque(Tstart), Corresponding stator load current(I2,start)
The following figures give the O.C.C. of d.c. Shunt generator driven at a constant speed of 700r.p.m.Terminal voltage (V): 10 20 40 80 120 160 200 240 260Field Current (A) : 0 0.1 0.24 0.5 0.77 1.2 1.92 3.43 5.2Determine the critical resistance at (a) 700 r.p.m. (b) 850 r.p.m. If resistance of field coils is 50 Ω, findthe range of the field rheostat required to vary the voltage between the limits of 180 V and 250 V on opencircuit at a speed of 700 r.p.m.
Q20) A 1000rpm DC shunt generator is supplying 100 lamps of 60W at 230V, the armature and field resistance are respectively 0.1Ω and 115Ω.Calculate the generated emf. a. 232.809 V b. 222.809 V c. 212.809 V d. 242.809 V
Q19) A 1000rpm DC shunt generator is supplying 100 lamps of 60W at 230V, the armature and field resistance are respectively 0.1Ω and 115Ω.Calculate the Load current. a. 16.09 A b. 36.09 A c. 26.09 A d. 46.09 A
4. Two shunt generators operating in parallel have each an armature resistance of 0.02 . The combined external load current is 2500 A. If the generated e.m.fs. of the machines are 560 V and 550 V respectively, calculate the bus-bar voltage and output in kW of each machine. Subject: Electrical Machine 1
A 6-phase ∆-connected 1600 V (line-to-line), 150 kW, 50 Hz, six-pole induction drive is used in an electric car. The drive has the following parameter values in Ω/phase referred to the stator: R1 =0.334 Ω R2 =0.168 Ω Rm1 = 125 Ω X1 = 0.273 Ω X2 = 0.287 Ω Xm1 = 16.78 Ω The total friction, windage, and core losses may be assumed to be constant at Prot =773 W, independent of load. For a slip value of s=0.015: a) Draw the equivalent circuitb) Compute the speed, output torque, power and stator currentc)Determine the power factor and whether leading or lagging d)Calculate the efficiency when the motor is operated at rated voltage and frequency.
In the design shown in the figure, the two-stage reducer transmits the motion of the electric motor to the fabric(kumaş) winding system. Find the motor power in Watts depending on what is given. The gear numbers of the gears are z1, z2, z3 and z4; The yield of the 1st and 2nd stages is 0.99 and 0.99, respectively, the yield of each bed = 0.99. Coupling efficiency will be taken as 1. The diameter of the drum is Dt mm, the fabric speed = 2.7 m / sec and the belt is pulled with a force of 1967 N during operation. EXPLANATION: 1-) Pi number will be taken as 3 when necessary. 2-) Decimal numbers with commas and 2 (two) digits after the comma.
A three-phase, 4-pole IM draws 55kW real power from a three-phase 60Hz feeder. The copper and iron losses in the stator amount to 4kW. If the motor runs at 1740 rpm, draw power flow and calculate: a) the airgap power. b) the rotor loss. c) gross mechanical power. d) if the mechanical loss is 2kW, calculate the efficiency of the motor.
Two shunt generators and a battery are working in parallel. The open circuitvoltage, armature and field resistances of generators are 250 V, 0.24 ohm, 100ohms and 248V, 0.12 ohm and 100 ohms respectively. If the generators supply thesame current when the load on the bus-bars is 40 A. Calculate the e.m.f. of thebattery if its internal resistance is 0.172 ohm.(Ans. 248
| 40% | Part B: If the load Speed-Torque characteristics (including the mechanical | Tasses) is described by following equation: TL= [11.1+(§/150) Nrl, as shown in Fig 1. | Determine the speed control range(masimum range) for three of the following ases: | a- Reducing the stator voltage using autotransformer. b- Inserting extemal rotor resistance. [ | Reducing the input voltage by 35%. | | o Reducingteiopus voiage st V=085 Ve
Attached are the examples mentioned in the question below. These are examples from a textbook, not a graded exam or assignment so please do not reject. Question: The synchronous machine of Examples 5.1 and 5.2 is to be operated as a synchronous generator.For operation at 60 Hz with a terminal voltage of 460 V line-to-line, calculate the field currentrequired to supply a load of 85 kW, 0.95 power-factor leading. given Solution:46.3 A Can someone explain how to reach this answer? I've tried to figure it out in several ways but the closest answer I got was 54.6 A. Thank you!
40. A short shunt compound generator supplies a current of 80 A at 110 V. If the resistances of the armature, shunt field and series field are 0.025 ohm, 40 ohms and 0.02 ohm respectively, calculate the induced emf.