Emf produced by windings, Electrical Engineering

Assignment Help:

Q. emf produced by windings?

The time variation of emf for a single conductor corresponds to the spatial variation of air-gap flux density. By suitable winding design, the harmonics can be reduced appreciably, and the waveform of the generated emf can be made to approach a pure sine shape.

1677_emf produced by windings.png

Figure shows an elementary single-phase, two-pole synchronous machine. In almost all cases, the armature winding of a synchronous machine is on the stator and the field winding is on the rotor, because it is constructionally advantageous to have the low-power field winding on the rotating member. The field winding is excited by direct current, which is supplied by a dc source connected to carbon brushes bearing on slip rings (or collector rings). The armature windings, though distributed in the slots around the inner periphery of the stator in an actual machine, are shown in Figure (a) for simplicity as consisting of a single coil of N turns, indicated in cross section by the two sides a and -a placed in diametrically opposite narrow slots. The conductors forming these coil sides are placed in
slots parallel to the machine shaft and connected in series by means of the end connections.

The coil in Figure (a) spans 180° (or a complete pole pitch, which is the peripheral distance from the centerline of a north pole to the centerline of an adjacent south pole) and is hence known as a full-pitch coil. For simplicity and convenience, Figure (a) shows only a two-pole synchronous machine with salient-pole construction; the flux paths are shown by dashed lines. Figure (b) illustrates a nonsalient-pole or cylindrical-rotor construction. The stator winding details are not shown and the flux paths are indicated by dashed lines.


Related Discussions:- Emf produced by windings

What are the cautions to be taken, What are the cautions to be taken before...

What are the cautions to be taken before starting work on electrical installations? Ans: Before starting any electrical works on installations disconnect the power supply to

Example of binary subtraction - positive number , Example  of binary  sub...

Example  of binary  subtraction - positive number Case 1.   Positive  number is more than negative number ( i e, answer is positive)   Example   subtract  4510 ( 1011012

Requirement specification for the monitor and alarm system, Prepare a User ...

Prepare a User Requirement Specification for the monitor and alarm system. User Requirements Specification should be written in a clear and unambiguous manner to state: • The

What ratio is needed for the cable, Q. If b and a are the radii of the oute...

Q. If b and a are the radii of the outer and inner conductors, respectively, of a coaxial cable using a polyethylene dielectric (ε r = 2.26), what ratio b/a is needed for the cabl

Pinch off voltage, Pinch off Voltage: The current in N-JFET because of...

Pinch off Voltage: The current in N-JFET because of a small voltage V DS  is described by: I DSS = (2a) W/L (qN d μ n V DS ) In which 2a  = channel thickness

.voltmeter, circuit diagram,working and construction of voltmeter

circuit diagram,working and construction of voltmeter

Find the speed of the motor, Q. A 10-kW, 230-V shunt generator, with an arm...

Q. A 10-kW, 230-V shunt generator, with an armature-circuit resistance of 0.1  and a field- circuit resistance of 230 , delivers full load at rated voltage and 1000 r/min. If the

Input bias current of operational amplifier, Q. Input bias current of opera...

Q. Input bias current of operational amplifier? When operated at extremely low quiescent current values, the base bias currents will be low; but they do have to be taken into c

Design 100 two-motion selectors, Design : Rather than 100 two-motion selec...

Design : Rather than 100 two-motion selectors as in the case of Design 3, let's consider only 24 two-motion selectors. In the case 24 simultaneous calls can be put through the swi

Continuity equation - zero electric field, Continuity Equation: Expla...

Continuity Equation: Explain continuity equation and discus the special case of continuity equation when concentration is independent of time and with zero electric field.

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