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

Address bus - bus organisation , Address Bus The address  bus is the gr...

Address Bus The address  bus is the group  of 16 lines. It is used  to carry  the address of memory  location and  addresses  of input  and output  ports as shown. It is a unid

Explain effect of impurity on conductivity of semiconductor, Explain the ef...

Explain the effect of impurity on the conductivity of a semiconductor. To form a semi-conductor conductive, a small amount of appropriate impurity is added. This is then termed

Explain biased and double clipper circuits, Q. Explain biased and double c...

Q. Explain biased and double clipper circuits.   Clipper can be either forward biased or reverse biased. If a battery is connected in series with the diode in a positi

Determine whether the systemnoise, The expression given in Problem for (S 0...

The expression given in Problem for (S 0 /N 0 )PCM is plotted for a sinusoidal message in Figure to show the performance curves for a PCM system using a polar waveform. (a) Comm

Actual voltage reading in decimal, Prepare the assembly code to make a Digi...

Prepare the assembly code to make a Digital Volt Meter that shows the message and the correct voltage on the LCD. Once you managed to display the hex value for the conversion you w

Show n-channel depletion mode mosfet, Q. For a transistor, when v GS = -2....

Q. For a transistor, when v GS = -2.0 V, find V DSsat if Vp= -4.0 V for an n-channel depletion mode MOSFET. Solution: V p = -(V DSsat + v SG ) but  v SG = -v GS = -(-

Transformers, determine the efficience of a 16 KVA transformer for the full...

determine the efficience of a 16 KVA transformer for the full-load,unit power factor

Explain the meaning of amplitude modulation, a. Explain the meaning of ampl...

a. Explain the meaning of amplitude modulation? Show that the AM output having two sidebands and the carrier frequency. b. Illustrate that the equivalent parallel impedance of a

Programming, ELEC 132 COURSEWORK – ADC This work will be assessed based...

ELEC 132 COURSEWORK – ADC This work will be assessed based on program demonstration (during lab sessions) and design. You will also have to submit your c-source codes as word o

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