Dc Generator Flashcards
The yolk of the DC Machine is made of
Cast Steel
Cast steel is used for its strength and durability in the construction of DC machines.
The armature of the AC machine is made of
Silicon Steel
Silicon steel is preferred for its magnetic properties, which enhance efficiency.
The coupling field between the electrical and mechanical of a DC machine is
Magnetic Field
The magnetic field plays a crucial role in the operation of DC machines.
The real working part of the machine is the
Armature Winding
The armature winding is essential for converting electrical energy into mechanical energy.
What is the primary purpose of the armature winding in a DC machine?
To facilitate commutation
Commutation is the process of switching the current direction in the armature winding.
What component of a DC machine carries all the flux?
The yolk
The yolk is part of the magnetic circuit in a DC machine.
How many poles does a 4 pole DC machine have?
Four
The number of poles is essential for determining the machine’s magnetic circuit.
What type of pole arrangement is used in the field structure of a DC machine?
Salient Pole arrangement
Salient poles are projections on the surface of the rotor or stator.
How many poles do small DC machines generally have?
2 poles
Smaller machines typically use fewer poles for simplicity and efficiency.
Why is the armature of a DC machine laminated?
To reduce eddy current loss
Laminating helps to minimize the circulating currents that can cause energy loss.
What type of current flows in the armature conductors of a DC machine?
AC
Despite being a DC machine, the armature produces alternating current due to its rotation.
Where does the greatest eddy current loss occur in a DC machine?
In the armature
Eddy currents are induced in the conductive parts of the armature.
What is the typical brush voltage drop in a DC machine?
About 2 volts
This drop is significant for the overall performance of the machine.
Why are carbon brushes used in a DC machine?
Because they provide good conductivity and wear resistance
Carbon brushes are preferred for their durability and conductivity.
The armature winding of a DC machine is a _______ winding.
closed circuit
A closed circuit is essential for current flow and operation.
What is the commutator pitch for a simplex lap winding?
1
The pitch determines the connections in the winding arrangement.
In a simplex wave winding, the number of parallel paths is equal to _______.
the number of poles
This relationship is crucial for understanding the winding configurations.
In a DC machine, the number of commutator segments is equal to _______.
the number of coils
This equivalence is important for proper commutation and functionality.
