CLASSIFICATION OF DC MACHINE

 Classification of DC Machine

DC Machines have been classified into multiple categories based on the connection of field winding and armature winding. The connections are mentioned below :-


Separately Excited

In Separately Excited DC Machine there is isolation between field circuit and armature circuit.

Separately Excited DC Machine

a) Voltage excited:- Long thin wired having higher resistance is used.

b) Current excited:- Short thin wires having low resistance is used, a constant current is wired from any other sources.


Self Excited

a) Series excited:- In series excited dc machine there is flow of common current in field winding and armature winding.

Series Excited DC Machine

b) Shunt excited:- In shunt excited dc machine there is common voltage across field winding and armature winding.

Shunt Excited DC Machine

c) Compound excited:- In this type of Machine there are two field winding out of which one is Shunt Connected and other is Series Connected. The flux in machine is due to both series as well as shunt winding.

1. Cumulatively Compound:- If both fluxes are added it is called as Cumulatively Compound. 
2. Differentially Compound:- If both fluxes are subtracted it is called as Differentially Compound.

There are two constructions for cumulative compound as well as differentially compound based on placement of series and shunt field coils.