Open circuit (or) No load characteristics of dc shunt generator
To get this characteristic, dc shunt generator is run with its load circuit open at constant speed.
The excitation current through field winding is increased from zero and the emf. induced at ach value of the field current is noted.
Then the graph is plotted taking field current along X axis and the induced emf. along the Y axis.
This characteristic is also called as magnetization characteristics of dc shunt generator
When the field current is less, the induced emf. will be directly proportional to the field current and it increases along the straight line AC as shown in the figure.
When the field current is increased beyond certain level its field magnet gets saturated.
Therefore the induced emf. will not increase proportion to the field current, and it is increases along the curve CD as shown in he above figure.
No comments:
Post a Comment