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 max  to  min  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

Can you explain working principle of tl - ac alternator, Can you explain wo...

Can you explain working principle of TL/AC alternator? Ans . The core of the stator which is completely induced by the field coils, will get a residual magnetism if excited b

Find the voltage regulation and efficiency of the line, Q. A60-Hz, three-ph...

Q. A60-Hz, three-phase transmission line has a total per-phase series impedance of 35+j140 .Ifit delivers 40 MW at 220 kV and 0.9 power factor lagging, find: (a) The voltage, c

For carry flag - return instructions , For Carry Flag  RC (Return of ...

For Carry Flag  RC (Return of Carry) and RNC ( Return on no Carry) Instruction RC returns from  the subroutine  to the calling  program if carry  flag is et (CY= 1). The

What are program-invisible registers, What are program-invisible registers?...

What are program-invisible registers? The local and global descriptor tables are determined into the memory system. So as to access and give the address of these tables, the pr

What are the application specific instruction processors, What are the appl...

What are the application specific instruction processors? Single purpose processor or ASIP (Application Specific Instruction processor) a. Floating point Coprocessor and Gra

Define the tick of the property, Tick of the property, which is different f...

Tick of the property, which is different from the group (A) Ductility.                (B) Resistivity. (C) Tensile strength.   (D) Hardness. Ans: Tick of the pr

Data rates in pstns, Data rates in PSTNs: A voice channel in a PSTN is ...

Data rates in PSTNs: A voice channel in a PSTN is band limited with a nominal bandwidth of 3.1 kHz. A first-cut estimate of this can be attained from Nyquist's theorem that app

What do you mean by number systems, Q. What do you mean by Number Systems? ...

Q. What do you mean by Number Systems? The Digital circuits are inherently binary in nature, but numerous types of representations of numerical data are in use. The represen

Find percent error of both meters when measuring a current, Q. Error specif...

Q. Error specifications on a 10-A digital ammeter are given as 0.07% of the reading, 0.05% of full scale, 0.005% of the reading per degree Celsius, and 0.002% of full scale per deg

Partial derivatives - transistor hybrid model, Partial derivatives - Transi...

Partial derivatives - Transistor hybrid model: The partial derivatives are taken by keeping the collector voltage or base current constant as pointed out by the subscript atta

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