Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
The various parts of transformers are Core,Limb,Yoke,Windings,Conservator,Breather,Explosion vent,Buck holz relay
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
The simple elements of a transformer consists of two coils having mutual inductance and a laminated steel core.
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
A transformer is a static device, which transfer electric power from one circuit to another circuit without change in frequency.
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
They are used where the speed has to remain nearly constant with load and where a high starting torque is not required.
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
The characteristics curve of a motor are (i) Torque and armature current characteristic (Ta/Ia) (Electrical characteristic).(ii) Speed and armature current (N/Ia) characteristic.(iii) Speed and torque characteristic (N/Ta) (Mechanical characteristic).
with Solved Example Problems
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
The speed of the motor is diretly proportional to back emf (Eb) and inversly proportional to flux (ϕ).
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
Torque is turning or twisting force about an axis torque is measured by the product of force and the radius at which the force acts.
with Solved Example Problems
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
The field winding is excited by a separate DC source.The connection diagram of a separately excited DC motor.
with Solved Example Problems
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
In a DC motor when the armature rotates, the conductors cut the lines of force of magnet field, so that an emf is induced in the armature.
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
The basic principle is whenever a current carrying conductor is placed in a magnetic field the conductor experiences a force whose direction is given by fleming's left-hand rule.
Electrical Machines
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
DC motors convert electrical energy into mechanical energy.
Subject and UNIT: Basic Electrical and Electronics Engineering: Unit II: Electrical Machines
Shunt generators are used for supplying nearly constant loads. They are used for battery charging, for supplying the fields of synchronous machines and separately excited DC machines.