The three-phase alternator, Electrical Engineering

Assignment Help:

The Three-phase alternator

In this case, three separate sets of coils are wound on the stator and connected to produce three separate outputs. Because of the physical displacement of the coils around the stator, the outputs will have different phases with respect to each other. Three-phase systems are common even when DC outputs are required (e.g. electric alternators to charge a car battery) because of the torque reaction problem mentioned above. The AC output is rectified with a set of six diodes mounted in a single pack (two diodes are needed to rectify each phase).

A  two-pole, three-phase alternator is shown in the diagram below. Stator coils AB belong to phase 1, coils CD to phase 2 and coils EF to phase 3. Each pair of coils are connected  in series and their outputs add (e.g. A and B are connected in series to  produce  phase  1  output).  Notice  it  is two-pole because there are only two poles (i.e. one pole pair) on the rotor. The frequency of each phase output is therefore equal to the rotational speed of the rotor.

1357_The Three-phase alternator.png

 

 

 

Unlike the single-phase  alternator, it turns out  that  the  torque  required  to  drive  a three-phase alternator is constant, with no pulsating component. This is an important advantage.The figure below shows the arrangement for   a     multipole   three-phase   alternator. Again, coils A&B, C&D and E&F are connected in series to three differnet outputs, each with a phase shift  of 120° apart (because of the physical arrangement of the coils on the stator).

1646_Three-phase alternator.png

 

 


Related Discussions:- The three-phase alternator

Lossy transmission line, Q. The model of an elemental length of a lossy tra...

Q. The model of an elemental length of a lossy transmission line is shown in Figure (a), along with its parameters, where R is series resistance per unit length, L is serie

Classify the conducting materials, Classify the conducting materials. ...

Classify the conducting materials. Conducting materials are classified by low resistivity materials and high resistivity materials. Low resistivity materials: The conduct

Sketch a graph comparing the fcc class, a) In the United States, the Federa...

a) In the United States, the Federal Communications Commission (FCC) is charged with the regulation of radio and wire communication (FCC part 15). It basically sets limits on the

Explain time multiplexed space switching, Explain time multiplexed space sw...

Explain time multiplexed space switching? With a neat diagram illustrate its operation. Ans: Time division switches where an outlet or an inlet corresponded to a single s

Information processing, Information Processing: Information processin...

Information Processing: Information processing is the key to improving cutting and productivity costs of excess work. Converting information to a computerized format in GIS i

Strain gauge bridge circuit, Explain kinds of strain gauge bridge circuits ...

Explain kinds of strain gauge bridge circuits and resistance strain gauges.

Power factor correction, i want to prodused domestic power factor correctio...

i want to prodused domestic power factor correction like industial

Compare with register, Compare with Register The contents  of the re...

Compare with Register The contents  of the register  are compared with  the contents  of the accumulator  here  register  may be  any one  of the  A, B, C, D E, H, or L  reg

Show voltage wave form of rlc series circuit, Q. The voltage wave form of F...

Q. The voltage wave form of Figure is applied to an RLC series circuit with R = 2, L = 2H, and C = 1 F. Obtain i(t) in the series circuit. (Note that the capacitor and inductor va

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