Generators 030103d Flashcards
What are the two basic components of an electric generator?
Objective 1 Page 4
Magnetic Field
Wire loops or coils
What does the magnetic circuit do in a generator?
Objective 1 Page 5
Provides the complete path for the magnetic lines of force in the magnetic field.
What four things does the magnetic circuit consist of?
Objective 1 Page 5
Field Yoke(Frame) - Metallic housing that provides a means of attachment and mechanical protection for the interior components.
Pole Cores - Metallic poles that the conductor coils are wrapped around
Armature - Central rotating part that holds the conductors.
Air Gap - space between the armature and stationary poles.
What are the three electrical components of a generator?
Objective 1 Page 5
Field Coils - Conductors wound around the pole cores.
Armature Windings - Conductor coils wound around the armature core.
Brushes - Provides a current path through a sliding connection from the rotating armature core to the output terminals.
What does each finger represent in the left hand rule for generators?
Objective 1 Page 2
Thumb - Direction of the movement of the conductor
Index Finger - Direction of the magnetic field from north to south.
Centre Finger - Direction of current flow.
What is the generated voltage in a conductor dependant on?
Objective 2 Page 7
The angle at which the conductor crosses the magnetic lines of force.
What are the four factors that affect the amount of voltage that is produced in a generator?
Objective 2 Page 10
Angle the conductor cuts the lines of force.
Speed at which the conductor is cutting the lines of force.
Flux density. Concentration of lines of force.
Length. If the conductor length is increased, it will cut more lines of force.
What happens to polarity as a conductor is rotated through a magnetic field?
Objective 2 Page 9
Polarity reverses for each half of the rotation.
At what angle is the maximum voltage generated for a conductor cutting lines of force?
Objective 2 Page 9
When the conductor is at right angles to the lines of force. (90°)
When at this angle it is cutting lines of force at a higher rate.
What is a split ring also referred to as?
Objective 3 Page 16
A Commutator
A generator that utilizes a commutator provides what type of current?
Objective 3 Page 16
DC Current
A generator that utilizes slip rings provides what type of current?
AC Current
What is a commutator?
A slip ring that is cut in half or split and each half is insulated from each other.
What is known as the neutral plane?
Objective 3 Page 13
The position where the armature windings are moving parallel to the magnetic flux lines. At this position there is no EMF or voltage being induced.
