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).
Q. Write short note on Quantization? Quantization: This is first step in PCM. Total amplitude range of the modulating signal is divided into a number of standard levels calle
name two types of axial flow turbines
describe torque angle in ships electrical propulsion system
Q. Explain the working principle of a Q meter. Also explain the factors that cause errors during a Q factor measurement. Ans. Working Principle of Q Meter: the q meter is
What is expanded memory system? EMS: The area at location C8000H-DFFFFFH is frequently open or free. Such area is used for the expanded memory system into a XT or PC system, or
Explain the suitability of copper that is used as electrical conducting materials. Copper : Pure annealed is utilized for the winding of electrical machines. High pur
derive transfer function of S= 2.25+j4.5
Dummy coils : These coils are used with wave winding and resorted to when the requirement of the winding are not met by the standard armature punching available in armature win
a) State the principle of working of transformer. b) A 230/110 V, single-phase transformer takes an input of 350 volt-amperes at no load while working at rated voltage. The core
Characteristics of unijunction transistor: Characteristics : The static emitter characteristic of UJT at a given inter base voltage VBB in shown in fig. From fig., it is no
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: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd