Characteristics of Series DC Generator

Characteristics of Series DC Generator Points : Characteristics of Series DC Generator In a series wound dc generator, the armature winding, field winding and external load circuit, all are connected in series with each other, therefore, the same current flows through all parts of the circuit. 1. Magnetic Characteristic If curve is drawn between flux per pole and field current, the magnetic characteristic is obtained, as represented by curve. This curve starts from point F little way up the field axis due to residual magnetism. 2. Internal Characteristic If there would not have been demagnetizing effect of armature reaction, this curve would have given the total flux, when the machine is supplying current to the external load circuit, but due to armature reaction the actual curve lies somewhat below this curve as represented by curve IL Since the emf generated in the armature is directly proportional to the actual flux at a constant speed, this curve also gives emf generated in the armature to some other scale. This curve is internal or total characteristic because it also gives relation between generated emf E_g and armature current I_a since I_a = I_f.