Parallel Operation of DC Shunt Generators

Generator 1 is connected to the bus bars and supplies the load. Generator 2 is required to be connected in parallel with generator 1 to supply a part of the load.

Procedure to be followed during paralleling of DC shunt Generators

Generator 2 is speeded up to the rated voltage by means of a prime mover. The switch S3 is closed and a voltmeter is placed across the open switch S2. The excitation of the generator is changed until the reading of the voltmeter connectrd across the open switch S2 is zero. At this instant, the voltage of the generator 2 is same as the voltage of the generator 1. When the switch S2 is closed, the generator 2 will be in parallel with generator 1. As a result, generator 1 supplies the entire load, whereas generator 2 is in floating stage. To shift the entire load from generator 1 to generator 2, the switch S1 must be opened. To shift the load manually as per requirement, the field rheostats of generator 1 and generator 2 is to adjust and the corresponding reading of current in ammeters A1 and A2 should be observed very carefully.