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

Calculate the current flowing through the inductor, The circuit is altered ...

The circuit is altered by replacing the capacitor, C1 with an inductor of 150mH and left with the switch in position (a) for a long time. At time t=0, the switch is moved from posi

Role of a bus arbiter in a multiprocessor configuration, Discuss the role o...

Discuss the role of a bus arbiter in a multiprocessor configuration. Bus arbiter: It functions to resolve priority among bus masters and permits only one device at a time to

Why we need digital systems, Q. Why we need digital systems? EASIER TO ...

Q. Why we need digital systems? EASIER TO PROCESS: For the reason that digitized information breaks all information into discrete units the information is easier to process and

Show example on residential wiring, Q. A person, while driving a car in a c...

Q. A person, while driving a car in a cyclone and waiting at an intersection, hears a thumping sound when a power line falls across the car and makes contact with the chassis. The

Explain the or gates - microprocessor, Explain the OR Gates - microprocesso...

Explain the OR Gates - microprocessor? The OR GATE has high or logic 1 output if any of the inputs are high. The output Q is true if input A OR input B is true (or both of t

Explain practical digital to analog converters, Explain Practical Digital t...

Explain Practical Digital to Analog Converters? In several DSP applications, we must reconstruct an analog signal after the digital processing stage. This is completed using a

Draw a block diagramfor a 2-to-4 decoder, Q. Draw a block diagramfor a 2-to...

Q. Draw a block diagramfor a 2-to-4 decoder. Obtain the truth table, and develop a logic diagram.

Find the nature of the armature voltage, Q. The flux-density distribution p...

Q. The flux-density distribution produced in a two - pole synchronous generator by an acexcited field winding is B(θ, t) = B m sin ω 1 t cos θ Find the nature of the armatur

Calculate the starting torque, A squirrel-cage inductionmotor operates at a...

A squirrel-cage inductionmotor operates at a slip of 0.05 at full load. The rotor current at starting is five times the rotor current at full load. Neglecting stator resistance and

Digital electronics, Design a logic circuit when to provide an output when ...

Design a logic circuit when to provide an output when any two or three of four switches are closed.

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