With the help of a labeled diagram explain, construction and working of an electric generator.
Hint: A dc generator (also known as dynamo) is an electrical machine that changes over mechanical energy to electricity. A DC machine comprises two fundamental parts; stator and rotor. Draw a line diagram of an electric generator and explain its various parts.
Complete step by step solution: A dc generator (also known as dynamo) is an electrical machine that changes over mechanical energy to electricity. A DC machine comprises two fundamental parts; stator and rotor.
Basic constructional parts of a DC machine are portrayed underneath:
1. Yoke: The external frame of a dc machine is called the yoke. It consists of cast iron or steel. It does not just give mechanical strength and stability to the entire machine yet additionally conveys the magnetic flux created by the field winding. 2. Poles and pole shoes: Poles are joined to the yoke with the assistance of bolts or welding. They convey field winding and shaft shoes are affixed to them. 3. Copper winding: Field loops are the previous wound and put on each shaft in a series arrangement. They are twisted so that they interchange North and South poles. 4. Armature core: Armature core is the rotor of a dc machine. It is round and hollow fit as a fiddle with openings to convey armature winding. The armature is developed of layered covered roundabout steel plates for diminishing eddy currents. 5. Armature winding: It is normally previous wound copper loops that rest in armature spaces. The armature conductors are protected from one another and the armature center. 6. Commutator and brushes: Physical contact with the armature winding is made through a commutator-brush game plan.
Working standard of a DC generator: According to Faraday’s laws of electromagnetic induction, whenever a conductor is placed in a varying magnetic field, an emf is induced in the conductor. The magnitude of induced emf can be calculated from the emf equation of the dc generator. In a DC generator, field curls produce an electromagnetic field and the armature conductors are pivoted into the field. Along these lines, an electromagnetically actuated emf is created in the armature conductors. The direction of the induced current is given by Fleming’s right-hand rule.
Note: One must not confuse between motor and generator. Both of them are different.