Electric Machine

From:- Ashok Soni BE (Electrical & Electronics) GGCT Jabalpur

Classification of electrical machinesElectrical machines

Static Machine

RotatingMachines

Transformer

Classification of electrical machinesElectrical machines

DC Machines

AC Machines

DC Generator

DC Motor

AsynchronousMachine

SynchronousMachine

SynchronousGenerator

SynchronousMotor

Induction Machines

1 phase 3 phase 1 phase 3 phase 1 phase 3 phase

DC Machines

Basically Dc machine divided in two parts:- 1. DC Generator 2. DC Motor

There are two types of generators, one is AC generator and other is DC generator. Whatever may be the types of generators, it always converts mechanical power to electrical power

DC Machines

There are two types of motor, one is AC motor and other is DC motor. It is an electro-mechanical device that converts electrical energy to mechanical energy.

Generators is based on the fundamental principle of  Faraday’s laws of Electromagnetic Induction.

DC Generator Generators is based on the fundamental

principle of  Faraday’s laws of Electromagnetic Induction.

According to these law, when an conductor moves in a magnetic field it cuts magnetic lines force, due to which an emf is induced in the conductor. The magnitude of this induced emf depends upon the rate of change of flux (magnetic line force) linkage with the conductor.

DC Generator Hence the most basic tow essential

parts of a generator are 1. A magnetic field and 2. Conductors which move inside that magnetic field.

Here N & S pole produce a magnetic flux & ABCD is a show conductor.

DC Generator

DC Generator

DC GeneratorThe nature of induced EMF in the DC

Generator is always a AC (alternating) nature. With the help of commutator this induced AC (alternating) nature emf is converted in to a DC nature.

DC GeneratorThe direction of induced current in the

conductor in DC generator is determined by Fleming Right Hand rule.

DC Generator

DC Motor This DC or direct current

motor works on the principal, when a current carrying conductor is placed in a magnetic field, it experiences a torque and has a tendency to move. This is known as motoring action. If the direction of electric current in the wire is reversed, the direction of rotation also reverses.

DC Motor

DC Motor When magnetic field and electric field

interact they produce a mechanical force, and based on that the working principle of dc motor established. The direction of rotation of a this motor is given by Fleming’s left hand rule,

DC MotorThe force which is experienced by DC

machine is determined by:-F = BIL

where, B = Flux DensityI = Current flowing in conductorL = Length of conductor

Construction wise a DC motor is exactly similar to a DC generator, but electrically it is just the opposite.