a) A six-pole, lap-wound, 220 V, shunt-excited d.c. machine takes an armature currentof 2.5 A when unloaded at 950 r/min. When loaded, it takes an armature current of54 A from the supply and runs at 950 r/min. The resistance of the armature circuit is0.18 S2 and there are 1044 armature conductors. For the loaded condition, calculate:the induced e.m.f.CS Scanned with CamScanneri.ii.the useful flux per pole.iii.the torque developed by the machine in Nm.

Answered: a) A six-pole, lap-wound, 220 V,…

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

Chapter12: Power System Controls

Section: Chapter Questions

Problem 12.4P

See similar textbooks

Similar questions

The resistance of the field winding(copper wire) of a DC machine is 0.25 ohm at 25°C. When operating at full-load, the temperature of the winding is 75 °C. The temperature coefficient of resistance of copper is 0.00427 per °C at 0°C. Find the resistance of the field winding at full-load.
a) A six-pole, lap-wound, 220 V, shunt-excited d.c. machine takes an armature current of 2.5 A when unloaded at 950 r/min. When loaded, it takes an armature current of 54 A from the supply and runs at 950 r/min. The resistance of the armature circuit is 0.18 and there are 1044 armature conductors. For the loaded condition, calculate: b) Use the information provided in Part (a) above to determine: i. The constant loss, C The output power when the machine is loaded. ii. iii. The output torque when the machine is loaded. Hint: Draw the power flow diagram.
A thicker wire is used in the DC series field winding than DC shunt field winding in DC machines. * O because it carries the load current. O to prevent mechanical vibrations. O to provide strength. O to produce large flux. The speed of a DC motor can be changed by varying - armature resistance circuit O flux per pole O voltage source O all of above
5. In relation to a compound d.c machine, choose the right statement from the following. (A) The resistance of the shunt field coil will be many times higher than the series field coil. (B) The resistance of the shunt field coil and the series field coil are of the same order. (C) The resistance of the series field coil will be many times higher than the shunt field coil. (D) Either of (A), (B) and (C) is true statement.
I:01)
dc machines
The armature of a d.c. The machine has a resistance of 0.25 ohm and is connected to a 300V supply. Determine the e.m.f. generated when it runs as a generator giving 100 A and as a motor taking 80 A.
The armature circuit of a free excited direct current motor with a nominal voltage of 600 V is fed from an adjusted direct voltage source. The excitation circuit is also powered from a regulated voltage source. It is used in an application that requires motor speed adjustment. The speed of the motor at the nominal armature voltage was measured as 1600 rpm. All losses of the motor and voltage source and the effect of armature reaction are neglected. It is accepted that the engine is not saturated.Answer the questions below.a) Draw the armature and excitation circuit of the motor and write the formulas for the equivalent circuit.b) If the load moment of the motor at the nominal armature voltage is 420 Nm, then calculate the armature current and the input power of the motor.c) If the armature voltage of the motor is kept constant at 600 V and the excitation current is decreased until the speed reaches 4000 rpm, then calculate the shaft moment. Show this working area on the M = f (W) axis.
q8
I need the complete solution.
Two shunt generations each having an armature resistance of 0.05 ohm and field resistance 40 ohms respectively are connected in parallel. The e.m.f include in one machine is 250 V and that induced in the other machine is 260 V. they supply together a load current of 2000 A. Determine:(i) Terminal voltage; and(ii) Output of each machine.
• A DC shunt machine while running as generator develops a voltage of 250 V at 1000 r.p.m. on no-load. It has armature resistance of 0.5 ohm and field resistance of 250 ohm. When the machine runs as motor, input to it at no-load is 4 A at 250 V. Calculate the speed and efficiency of the machine when it runs as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4 %

SEE MORE QUESTIONS

Recommended textbooks for you

Power System Analysis and Design (MindTap Course …

Electrical Engineering

ISBN:

9781305632134

Author:

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

Publisher:

Cengage Learning

Delmar's Standard Textbook Of Electricity

Electrical Engineering

ISBN:

9781337900348

Author:

Stephen L. Herman

Publisher:

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

Delmar's Standard Textbook Of Electricity

Electrical Engineering

ISBN:

9781337900348

Author:

Stephen L. Herman

Publisher:

Cengage Learning

SEE MORE TEXTBOOKS