D.c. generator, Electrical Engineering

Assignment Help:

D.C. Generator

250_DC generator.png

A magnetic field is produced by afield coil supplied with a D.C. current and a rotor is placed between shaped pole pieces and wound with an armature winding. The diagram above shows only one turn of the armature winding, but in practice there will usually be more than one. The ends of the armature winding are connected to two slip rings that rotate with the armature and the voltage generated is 'picked off' the rings by brushes that bear against the slip rings

 

690_brushes , rings armature winding , rotor.png

The emf generated may be calculated either using the equation for the emf induced in a conductor of length l moving

in an electric field of flux density B webers/m 2

e=B.l.v

with a velocity v m/sec or by considering the rate of change of flux linkage with the armature coil. We shall use the latter method. Due to the shaping of the pole pieces, the flux threading through a particular armature  coil  is  constant  at  +  max   as  it turns from O4   to  O1 and decreases linearly from +Ømax  to  -Ømin  while  the  rotor  is turning from  O1 to O2 . It is constant again during O2 to   O3 and then increases linearly during  O3to O4. (ref graph)

 

1313_D.C. Generator 1.png


Related Discussions:- D.c. generator

Semiconductor devices, Semiconductor Devices: We have studied semicond...

Semiconductor Devices: We have studied semiconductor devices. Firstly, we understand what semiconductors in terms of energy band diagrams are. Then we understand what is dopin

Electric Circuit, The manufacturer of a 6V dry-cell flashlight battery says...

The manufacturer of a 6V dry-cell flashlight battery says that the battery will deliver 15 mA for 60 continuous hours. During that time the voltage will drop from 6V to 4V. Assume

Plc - programmable logical controller , PLC ( Programmable Logical  Contr...

PLC ( Programmable Logical  Controller ) PLC  stand for programmable logical  controller.  PLC   is an  industrial computer  used to monitor inputs and depending upon  their  m

Ac, power factor improvement

power factor improvement

Explain stator of a synchronous machine, Explain Stator of a Synchronous Ma...

Explain Stator of a Synchronous Machine? The stator of a synchronous machine is made of thin laminations of highly permeable (silicon) steel in order to reduce the core losses.

Determine the current and voltage in given network, Q. For a part of the ne...

Q. For a part of the network shown in Figure, given that i 1 = 4A; i 3 (t) = 5e -t , and i 4 (t) = 10 cos 2t, find v 1 , v 2 , v 3 , v 4 , i 2 , and i 5 .

Common-drain jfet amplifier, Q. Common-Drain JFET Amplifier? Figure (a)...

Q. Common-Drain JFET Amplifier? Figure (a) shows a CD JFET amplifier in which resistors R 1 , R 2 , and R SS are selected by the bias design, and capacitors CG and CS are chos

Determine the reactive kva of the motor, Athree-phase, wye-connected, round...

Athree-phase, wye-connected, round-rotor, 220- V, 60-Hz, synchronous motor, having a synchronous reactance of 1.27  per phase and negligible armature resistance, is connected in p

Intrinsic semiconductor, Draw a graph illustrating how resistivity varies w...

Draw a graph illustrating how resistivity varies with temperature for an intrinsic semiconductor. b) Gallium nitride, GaN, has an energy gap of 3.36 eV at 300 K. Calculate the w

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd