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On what basis is the power rating of the generator decided??
bittu123
- Nov 9th, 2011
The core criteria for deciding rating of machine is LOSSES. while this may ultimately justify all the reason specified by above person. Because temperature rise of machine depend on losses. Insulatio...
raviiisc
- Jun 9th, 2011
For any electrical equipment the power rating is decided by the thermal rating.orThe temperature withstanding capability of the machine.For generator the power rating depends on temperature, volume of rotor.
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How torque is developed in motor ?
raviiisc
- Jun 9th, 2011
It is due to the interaction of one flux and one current.For example in Motor (induction motor 3-phase), the stator flux interacts with the rotor current leads to torque development.Somebody also says...
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Large Size Synchronous Machines
Why almost all large size synchronous machines are constructed with rotating field system type?
Rhombus
- Jun 11th, 2011
All the large size synchronous machines have rotating field winding because in the other case where armature is rotating we require four slip rings.. but in case of rotating field we can do with only..2 slip rings..!! :):)
veerateja
- Jul 11th, 2010
Large size synchronous machines or Alternators have rotating field winding on rotor for many reasons of them the important reasons are:- 1. The rotor can rotate at very high speeds. 2. The voltage reg...
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What should be power angle for 11KV AC generation ?
For 600 MW Generation Purpose.
raviiisc
- Jun 9th, 2011
It will be 30 to 45 degrees.We wont allow the generator to operate at its maximum power transfer such as 90 degrees.At this the reactive power supplied by generator is the leading reactivepower. But w...
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Power Generation
What measures will take for cost saving in utility and power generation
bittu123
- Nov 9th, 2011
POWER GENERATION 1. Try to increase "Diversity factor" as much as u can. 2. Try to increase "Load factor" 3. Try to decrease "Maximum demand" UTILITY : 1. Use Power factor improvement instrument lik...
Nishant Choudhary
- Jun 3rd, 2011
The first thing always be remembered that for economical purpose the power factor should always be kept around unity or close to unity this u can do by avoiding light loads or by using APFC panels to improve power factor
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Explain how direct current is produced in single-loop d.c. generator?
Nishant Choudhary
- Jun 3rd, 2011
The current produced in the armature is ac current but the commutator segment and the brushes acts as mechanical rectifier which converts ac voltage to dc voltage
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Relay setting details
How to set the various setting value of a relay depend upon the electrical motors ?
Nishant Choudhary
- Jun 3rd, 2011
Its very simple first note the current rating of the motor on the name plate then adjust the current setting just above the name plate motor of the motor
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Ferroresonant transformer
What is a ferroresonant transformer and what is its working principle?
Nishant Choudhary
- Jun 3rd, 2011
Ferroresonant transformer are constant voltage transformer they maintain the output power to constant for any variation in input
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How to run three phase induction motor as a generator
Abushama
- May 29th, 2011
Since the induction motor and Generator have the same constructor then running a motor as a generator is possible . if we want to run ?induction motor as a generator two things should be done , First...
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What is slip power and slip recovery ?
guthajimmy
- May 3rd, 2011
SLIP-POWER: A PART OF THE AIR-GAP POWER WHICH IS NOT CONVERTED INTO MECHANICAL POWER IS CALLED SLIP POWER. IT IS REPRESENTED BY sPg. &n...
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How is a 100 MVA transformer cooled?
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Syncronous Machines Slip
In syncronous machines, less slip is useful or more slip is useful? Why?
venky_sastra
- Dec 28th, 2008
A synchronous machine is defined as a machine which rotates with the constant speedslip= Ns-Nr/Nssince in syn m/c Ns=NrS=0The significance of slip comes only in induction machines where the slip exists.
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What is the reason of power development in synchronous generator due to saliency ?
abishgk
- Aug 13th, 2010
In salient pole synchronous machine has non-uniform air gap so the reactance will vary with rotor position. It has mainly two axis are there 1. Direct axis 2. Quadrature axis.
santosh soni
- Dec 21st, 2006
IN SALIENT POLE SYN. ALTERNATOR IT IS THE CHANGE IN THE RELUCTANCE WITH SPACE WHICH RESULT IN GENERATION OF BOTH RELUCTANCE POWER & ELECTROMAGNETIC POWER.
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What is the voltage that is supplied to the electric traction trains
nileshvalvekar
- Aug 12th, 2009
Above both answers are correct but at some level. The ans. should be 1) 25 Kv Ac system2) 1500 V Dc systemabove voltages are used depending on the system being used.
haveasafeday
- Feb 5th, 2008
Right that it is 25kv ac. But the traction motor is a DC series motor for on-load starting.
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How do we select a cable for a machine as per standards. Is there is any standard to select a cable as per voltage, or as per KVA and as per amps ratings?
prafulla patil
- Nov 15th, 2010
Cable size depends upon current carrying capacity and operating Voltage of Machine to select cable size also the Distance from the Supply Panel to Machine and way of laying cable under ground or on ca...
jatin patel
- Oct 16th, 2007
Cable size depends upon current carriying capacity and voltage to withstand,to select cable size we must have knowledge of load of machine and operating voltage
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Why we are using Sinusidol wave in all electrical systems?
SURAJTHEGREAT
- Apr 19th, 2011
We know flux(phi)=NBA cos(teta)e=-d(phi)/dttherefore on differentiating we gete=NBAw sinwt.ie.sinusoidal wave.Moreover when 3 phase are displaced by angle 120 with respect to each other,rotating magnetic field is produced.
cvk
- Oct 6th, 2007
Reson 1 is the way power is generated. Due to the construction of generators, the default wave form is sinusoidal. Secondly, the frequency of sine wave is a single definite value while other wave form...
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Why is r.m.s. value used to express a.c. quantities?
SURAJTHEGREAT
- Apr 10th, 2011
AC values are always alternating.Hence we cannot make a precise analysis!!!!So we use RMS value.Let us consider a bulb B.IF it is switched to position A(it is connected to ac supply).IF switched to po...
raviiisc
- Apr 9th, 2011
The rms value arised in the following manner:The heat dissipation with AC supply will found, then the DC supply is applied such that same heat production in resistor. That DC voltage value is said to ...
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Quiescent Point
What is a Quiescent Point (commonly called a Q-point)?
uttkarsh BIT
- Mar 26th, 2011
Quiescent or Q-point of any device is the intersection point of its characteristic curve and a given load line(or load curve). It actually is the most suitable point around which the device works under maximum efficiency.
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Apparent Power and Reactive Power
What is apparent power and reactive power?
Steeve Cantave
- Mar 15th, 2011
Apparent power is the power that is needed for the circuit to perform. In an AC circuit with resistive, capacitive, and inductive components, not all power is converted from electrical to non-el...
zaheerdahri
- Dec 23rd, 2010
Apparent PowerApparent power (S) is the power delivered to an electrical circuit. The measurement of apparent power is in voltamperes (VA).Reactive PowerReactive power (Q) is the power consumed in an ...
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