Electrical Engineering ⇒ Topic : Characteristics of DC Generators

There are three important characteristics of any dc generator.They are:

•   the open circuit characteristic (0.C.C.):

      Sometimes the O.C.C. is also known as the no-load magnetisation characteristic. It gives the relation between the generated emf on no-load and the field current when the machine is driven at its rated speed.

•      The external characteristic or the load characteristic: It gives the relation between the terminal voltage across the armature and the load current when the machine is driven at its rated speed.
•         The internal characteristic: It gives the relation between the generated emf with load and the load current when the machine is run at its rated speed.

        The definitions given above for the three characteristics are the same for all types of generators, whether they are separately excited, shunt, series or compound generators.

D.C. GENERATOR CHARACTERISTICS