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What happen when you reverse the direction of rotation in a separately excited dc generator?
Wiki User
∙ 11y ago
When reverse the direction of a seperately excited DC generator,only polarities has been reversed,i.e., (+) becomes (-) and (-) become (+).
Wiki User
∙ 11y ago
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What is the difference between a seperately excited DC generator and DC shunt generator?
The difference between a separately excited DC generator and a Shunt DC generator is that for a separately excited Dc generator , the excitation field winding is supplied by an external source different from that supplying the armature while for shunt generator, the excitation field windind is connected in series with the armature and supplied by a single source.
What will happen if the generator rotates in the opposite direction from that specified?
If the rotation is reversed in DC generator the permanent magnetism already occurred for voltage build up process may demagnetize. this will causes no emf induce at starting time.The reversal of rotation is not affect externally excited generators
How is the induced voltage of separately excited dc generator affected if the speed increases?
as speed increases, induced voltage increases
Why alternator is much less likely to burn out on a sustained short circuit than a separately excited dc shunt generator?
Because the Power Factor is over corrected.
What are the application of differential compound generator?
Differential compounded generators are used in Ward Lenard motor generator loops. The shunt fields on these generators are separately excited and when the shunt field polarity is reversed by the controller the series field helps drive the generator voltage to zero thus aiding in the reversal of current.
What is separately-excited generator?
in a separately excited generator the field coils are excited from a separate source like a dc battery may be or any other small generator. They are self starting generators.
Different types of DC generator?
There are two types me dc generator 1 separately excited dc generator 2 self excited dc generator
Can you use the separately excited shunt generator machine as self excited generator?
You have a seperately excited generator and then you have a shunt generator which has the field winding in parallel with the armature terminals. In DC machines a separately excited generator could be run as a shunt generator provided the field winding is designed to work on the generated voltage. A separately excited alternator needs a DC supply for the field winding. In car alternators that is taken from the main winding via a rectifier and a voltage regulator.
What is the difference between a seperately excited DC generator and DC shunt generator?
The difference between a separately excited DC generator and a Shunt DC generator is that for a separately excited Dc generator , the excitation field winding is supplied by an external source different from that supplying the armature while for shunt generator, the excitation field windind is connected in series with the armature and supplied by a single source.
What will happen if the generator rotates in the opposite direction from that specified?
If the rotation is reversed in DC generator the permanent magnetism already occurred for voltage build up process may demagnetize. this will causes no emf induce at starting time.The reversal of rotation is not affect externally excited generators
Answering Which one is a separately excited generator - ac generator or dc generator?
Excitation is the phenomenon by which you control the excitation of field winding of a generator. In DC generator field winding is placed on stator and this field winding can be self excited or seperately excited depending upon the type on generator used. AC generators can also be self excited or seperately excited type but field winding is placed on rotor nad armature winding on stator.
What is dc separately excited shunt generator?
Either or both can be separately excited. To generate voltage you need a big magnet( the field). Most generators use an electro-magnet. Now the electro-magnet needs a source of power (electricity). We could use the generators own output to excite the field (magnet), this is called self excitation. The problem with self excitation is that we have to wait for the generator to turn and start generating, also to start generating (Building up) there must be some left over magnetism from the last time it was run (called residual magnetism) or not even a little voltage will be generated to start the field current flowing. To solve these problems we could use separately excited. This means we must have a separate source of power to excite the field to produce the magnetism. Sometimes a battery or gasoline driven generator is used to excite the field of a very large generator to get it generating and then we can use some of the generated output to either recharge the battery or switch over to from the battery. In any case we have adjustable control of the generator all the time. This is why most generators are designed to be separately excited. And that is why you car has a voltage regulator. It wakes up the alternator when the engine is started by separately exciting it (the field) with the battery and then regulates the output voltage of the alternator as the engine changes speed with the driver's commands from the gas pedal.
How is the induced voltage of separately excited dc generator affected if the speed increases?
as speed increases, induced voltage increases
How the polarity of generator be the same with reverse rotation?
That would all depend on the construction and type of generator.A simple DC generator may use permanent magnets for the field. In this case, because the coils pass the field in the opposite direction, the output will be opposite.If the field windings are excited by an external source, the output can be controlled either way.
Why alternator is much less likely to burn out on a sustained short circuit than a separately excited dc shunt generator?
Because the Power Factor is over corrected.
When a shunt generator fails to build up the voltage then how to rectify the fault?
It fails to build up because self excited DC motor's armature have only one direction of rotation. So that if the poles of the armature are reversed, then this causes the reduction in the residual magnetism and eventually, it will stop.
What are the application of differential compound generator?
Differential compounded generators are used in Ward Lenard motor generator loops. The shunt fields on these generators are separately excited and when the shunt field polarity is reversed by the controller the series field helps drive the generator voltage to zero thus aiding in the reversal of current.
