Why Doesn't a Synchronous Machine Induce EMF in DC Field Wires?

In summary, the DC field wires in a synchronous machine do not produce induced EMF because they are connected to a steady DC power source, which does not cause a change in magnetic flux. This cannot be replaced with AC field wires as the type of wires does not affect induced EMF production. While there are ways to generate induced EMF in the DC field wires, it is not commonly done due to potential instability. However, not having induced EMF in the DC field wires can be advantageous for control and stability. Induced EMF can be produced in other parts of the synchronous machine, but the DC field wires are purposely designed to maintain a constant magnetic field.
  • #1
klmnopq
27
0
conflict: why synchronous machine doesn't produce induced EMF in the DC field wires

Isn't it current path through winding which produce magnetic field (rotating) the must produce EMF in the dc winding of field (same theory of induction)

but why isn't true in synchronous
 
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  • #2


Two questions:

1. What makes you think it doesn't?
2. What is releative motion between rotating field wires and the magnetic field in which they rotate?

Read up on "amortisseur windings".
 
Last edited:
  • #3


thanks very much
 

Related to Why Doesn't a Synchronous Machine Induce EMF in DC Field Wires?

1. Why does a synchronous machine not produce induced EMF in the DC field wires?

The DC field wires in a synchronous machine are responsible for producing a constant magnetic field. This magnetic field is necessary for the machine to operate, but it does not create any induced EMF. This is because the DC field wires are connected to a DC power source, which produces a steady current and does not change over time. Induced EMF is only created when there is a change in magnetic flux, which is not present in the DC field wires.

2. Can the DC field wires be replaced with AC field wires to produce induced EMF?

No, the type of field wires used in a synchronous machine does not affect the production of induced EMF. The key factor is the change in magnetic flux, not the type of current used. In fact, the DC field wires are more efficient for producing a constant magnetic flux, making them the preferred choice for synchronous machines.

3. Is there a way to generate induced EMF in the DC field wires?

Yes, there are methods to generate induced EMF in the DC field wires, such as by using a rotating armature or by varying the excitation current. However, these methods are not commonly used as they can cause instability and affect the performance of the synchronous machine.

4. Are there any advantages to not having induced EMF in the DC field wires?

Having a constant magnetic field in the DC field wires allows for better control and stability in the operation of the synchronous machine. It also reduces the risk of voltage fluctuations and damage to the machine. Therefore, not having induced EMF in the DC field wires can be considered an advantage.

5. Can induced EMF be produced in other parts of a synchronous machine?

Yes, induced EMF can be produced in other parts of a synchronous machine, such as in the stator windings or the rotor windings. These induced EMF are necessary for the generation of electrical power in the machine. However, the DC field wires are specifically designed to not produce induced EMF in order to maintain a constant magnetic field.

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