Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
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).
Direct and Indirect Semiconductors 1) In a common quantitative calculation of band structures, the wave function of a single electron traveling by a perfectly periodic lattice
Consider a GLC parallel circuit excited by i(t) = Ie st in the time domain. Assume no initial inductive current or capacitive voltage at t = 0. Draw the transformed network in the
Determine the current through each parallel branch of the system
polarity of dot convention
Explain all of your steps and follow a logical train of thought. Clearly describe all design rationale. 1) Design a device to deliver a sinusoidal 500kHz pulse through a piezoe
Synchronization: Whatever type of weep is used, it must be synchronized with the signal being measured. Synchronization has to be done to obtain a stationary pattern. This requir
What is tunnel effect? Discuss the Alpha decay as an example of tunnel effect. Prove that tunneling increases on decreasing the height and width of the barrier. Explain what do you
Explain hall affect and derive the mathematical expression for hall coefficient, also describe its applications. Sol. Hall effect If a metal or semiconductor material carr
Define the term Paging Unit. Paging Unit: The paging mechanism functions along with 4K - byte memory pages or along with a new extension obtainable to the Pentium with 4M byt
Semi-conductors have temperature coefficient of resistance. (A) Negative (B) Positive (C) Both positive and negative (D) none o
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!
whatsapp: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd