Abstract
When short circuit failures occur in a marine electric power generating system, the current of main a. c. generator should be maintained at not less than three times of it's rated value for two seconds. To satisfy this condition, the main generator must be excited by the current transformer (CT) at these short circuit faults.
The short circuit current decays with transient time constant of the main generator, but the current heats the feeder line and the voltage induced by the inrush current from CT may give a harmful influence upon the exciting system. Therefore, it is especially successful to make the short current rapidly reduce and to keep a certain short circuit current constant, from the view point of the generator protection and the circuit breaker behavior.
We have used the current limit cotrol apparatus annexed the bypass thyristor type AVR for above pourpose and we have analyzed the sudden short circuit current of the self-excited ac generator. The analytical results obtained are very much in agreement with the experimental results.
