Two shunt generators connected in parallel is inherently stable

Justify the statement:

Stability of operation is an important factor in the parallel operation of generators. Shunt generators share the load proportionately. Should anything to occur to upset this proportionate division of load, it would be desirable for the generators to restore automatically the division of load. Assuming that the speed governor of one of the motors driving the generators is such that it will not hold the speed constant and because of this condition the speed of generator 2 will increase. The increase in speed will produce a large r induced voltage in generator 2,which in turn will cause generator 2 to deliver more load. Of course ,if generator 2 delivers more of the load, generator 1 delivers less. This larger load upon generator 2 will cause more current to flow in the armature of generator 2,producing a larger I_aR_adrop, a larger drop due to armature reaction, and a larger reduction in armature current, all of which tends to oppose the increase in the induced voltage and thereby not allow the generator to deliver more current . In the meantime the load on generator 1 has decreased with a corresponding reduction in the I_aR_a drop and armature-reaction drop, and the field current increases slightly. All this factors tend to increase the generated voltage of generator 1. An increase in the generated voltage will cause the generator to deliver more, not less, load. Therefore generator 1 will tend to deliver the same amount of load instead of reducing the load. Thus the actions of both generators combine to maintain the proportionate division of load as originally set as justification requires.

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