Short note on DC generator
Classification of dc generators on the mode of field excitation, and short note on Dc generators. Which should be helpful in the field of electrical engineering. Which is a machine that converts mechanical energy into electrical energy
DC generator
An electrical generator is a rotating machine which usually converts mechanical energy into electrical energy for doing work. The energy changing is based on the principle of electromagnetic induction. According to Faraday's laws of electromagnetic induction, Whenever a conductor is feel motion in a magnetic field, emf induced dynamically in the conductor. When an external load is connected to the conductor this induced emf make a current flow in the load. Thus the mechanical energy which is given in the form of movement to the conductor is converted into electrical energy.
Dc generators can be classified as per their methods of field excitation. There are two types of dc generators on the basis of excitation.Separately excited Dc generators:-
If the field winding is excited by a separate dc supply from the external source, then the generator is called separately excited dc generators.Self excited Dc generators:-
If the field winding energy is supplied from the armature of the generator it self, then it is called self excited dc generators. Self excited dc generators are further classified as:- Series generator:-
In series generator field winding is connected series to the armature it self.
The voltage generated in series field generator is E(generated)=V(terminal voltage)+I(a)*R(a)+I(se)*R(se)+V(brush).
Power generated is E(g)*I(a).
Power delivered to the source is V*I(a). Shunt generator:-
In shunt generator field winding is connected across the armature or parallel to the armature.
The generated emf in shunt field generator is E(generated)=V(terminal voltage)+I(a)*R(a).
Power generated is E(g)*I(a).
Power delivered to the source is V*I(a). Compound generator
The compound generator consists of both shunt field and series field winding on its structure. One winding is series and other is in parallel with the armature of the generator. Depending upon the shunt field and series field connections of the compound generator can be classified as :-Long shunt compound generator:-
In a long shunt compound generator shunt field winding is connected parallel to both the series field and armature winding.
The voltage generated in series field generator is E(generated)=V(terminal voltage)+I(a)*R(a)+I(se)*R(se)+V(brush).
Power generated is E(g)*I(a).
Power delivered to the source is V*I(a).Short shunt compound generator:-
In short shunt compound generator shunt field winding is connected parallel with the armature and this combination is connected in series with series field winding of the generator. The voltage generated in series field generator is E(generated)=V(terminal voltage)+I(a)*R(a)+I(se)*R(se)+V(brush).
Power generated is E(g)*I(a).
Power delivered to the source is V*I(a).