Differential long shunt compound

Differential short shunt compound

Cumulative long shunt compound

Cumulative short shunt compound

Cork screw rule

Right hand palm rule

Fleming’s left-hand rule

Fleming’s right hand rule

$$Generated\ emf=\frac{\phi ZN}{60}\ Volt$$  

$$Generated\ emf=\frac{\phi ZN}{60}\times\frac{A}{P}\ Volt$$  

$$Generated\ emf=\frac{\phi ZN}{60}\times\frac{P}{A}\ Volt$$  

$$Generated\ emf=\frac{ZN}{60\phi}\times\frac{P}{A}\ Volt$$  

$$E_b=\frac{V}{I_aR_a}$$  Volts

$$E_b=V\times I_aR_a$$  Volts

$$E_b=V-I_aR_a$$  Volts

$$E_b=V+I_aR_a$$  Volts

Pole tip

Pole coil

Pole core

Pole shoe

Shunt generator

Series generator

Compound generator

Separately excited generator

Heat

Kinetic

Chemical

Mechanical

Short shunt compound generator

Long shunt compound generator

Differential compound generator

Cumulative compound generator

Cork screw rule

Fleming’s left-hand rule

Fleming’s right hand rule

Faradays laws of electromagnetic induction

BLV volts

BL sinθ volts

BLV sinθ volts

BLV cosθ volts

Cork screw rule

Right hand palm rule

Fleming’s left hand rule

Fleming’s right hand rule

Stator

Pole core

Pole shoes

Yoke (or) frame

4

6

8

12

Side end plates

Pole shoe lamination

Commutator segment

Armature core lamination

In series with armature

In parallel with armature

In series with shunt field

In parallel with shunt field

Build up the voltage

Reduce the field current

Reduce armature current

Maintain constant output voltage

Resistance between the opposite brushes

Resistance between brush and commutator raiser

Resistance between brush and commutator

Resistance between brush and armature conductors

Full load voltage drop

Armature voltage drop

Armature reaction drop

Shunt field voltage drop

Long shunt compound

Cumulative compound

Differential compound

Short shunt compound

Reduce the copper loss

Reduce the friction loss

Reduce the hysteresis loss

Reduce the eddy current loss

Reduce armature current

Reduce armature voltage drop

Run armature with less weight

Reduce the temperature of armature

Protect brushes from damage

Protect the residual magnetism

Avoid short circuit in armature

Avoid over loading of generator

Connect more loads

Reduce commutation effect

Neutralize armature reaction effect

Increase the efficiency of generator

Loose brush contact

Armature resistance is more

Field resistance is above critical resistance

Prime mover is running at above rated speed

Shunt generator

Series generator

Compound generator

Self excited generator

Reduce the air gap

Increase the field strength

Minimize the magnetic losses

Spread out flux uniformly in the air gap

Maintain constant voltage

Collects the current unidirectionally

Reduces the voltage drop at brushes

Increases the terminal voltage than rated

Steel and graphite

Carbon and graphite

Cast iron and graphite

Aluminium and graphite

Heavy short circuit in load

Running without load continuously of rotation very often

Continuous running without break

Change of direction of rotation very often

Field coils

Armature core

Laminated pole core

Winding conductors in armature

Because of armature reaction effect

Due to increased in armature resistance

Because of brush voltage drop decreases

Due to increased in shunt field inductance

Shunt generator

Series generator

Differential compound generator

Cumulative compound generator

Replacing the brushes frequently

Heating the machine by running periodically

Cleaning the commutator segments regularly

Blowing hot air in to the machine during maintenance

Shunt generator

Series generator

Compound generator

Separately excited generator

Shunt generatorcompound generator |

Series generator

Differential compound generator |

Cumulative compound generator |

Low current low voltage

High current low voltage

Low current high voltage

High current high voltage

Maintain constant voltage

Nullifying statically induced emf

Increasing statically induced emf

Smooth reversal of current direction

To reduce the copper loss

To increase the residual magnetisme

To decrease the residual magnetism

To reduce the reluctance of magnetic path

Cast iron

Soft iron

Aluminium

Rolled Steel

Supplies output continuously

Makes output in the uni direction

Makes output in the opposite direction

Collects the output from alternate conductors

Pulsating voltage

Oscillating voltage

Alternating voltage

Direct current voltage

To fix the key way

To make air circulation

For lubrication purpose

For easy removal from shaft

To increase the flux in air gap

To decrease the magnetizing current

To magnetize the poles to produce coil flux

To increase the reluctance of magnetic path

Soft iron

Soft iron

Cast steel

Stainless steel

Reduce the friction loss

Reduce the windage loss

Reduce the hysteresis loss

Reduce the eddy current loss

Shunt generator

Series generator

Differential compound generator

Cumulative compound generator

Minimizes rough commutation

Maintain constant output voltage

Neutralizes the demagnetizing effect

Decreases the excitation current of field coils

Output voltage is pulsating

Output voltage is above normal

Generator fails to build up voltage

Generator builds up voltage normally

Output voltage increases

Output voltage decreases

Output voltage is pulsating

Output voltage will become zero

178 V

243 V

357 V

428 V

Using compensating winding

Providing additional inter poles

Increasing brush contact resistance

Adding resistance wires with winding

Field coil resistance increases

Armature resistance increases

Increase the armature reaction

Looses its residual magnetism

160V

320V

480V

640V

Induced emf increases

Induced emf decreases

No change in induced emf

Induced emf becomes zero

Short circuit in field winding

Short circuit in armature winding

MNA and GNA position changed

Too much spring tension at brush