What Are Circulating Currents in AC Generators?

When an electrical generator is in operation, it is capable of generating alternating current that can make the current circulate. The circulating current is just similar to a current flow that you can see in a river or even other water situation. The current circulates by moving back and forth between the two generator fields. When you want to design a generator set and also determine the placement and synchronization of generator, you have to know and understand the operation of circulating current, know the condition that can cause it to be more or less prevalent, plus also to understand the correct way to mitigate any of the effects provide by the circulating current.

All you need to know about circulate currents in AC generators:

  • Multiple generators
  • Circulating currents travel a certain particular path
  • It travels differently through many generators
  • It can cause a variety of problems for electrical circuits

Circulating Currents in AC Generators

What Are Circulating Currents in AC Generators?

  • If there are more than one generator start to operate at the same time, you will be able to see the occurrence of circulating current
    • Whenever you see two or more generators started to operate in synchronization, you will definitely find circulating currents in your AC generators.

    A single generator will not be able to circulate current from the generator.

  • Circulating currents needs a particular path so that it can travel between the generators that you are using as part of a group.
    • Circulating currents travel by leaving the line leads of the first generator before moving through the parallel bus of the second generator and then return to the second generator.
    • The load side of the generator will not be used by a circulating current because there is lots of existing current or electrical flow at the load side resulting from the generator output.
    • Circulating currents will only move onto the path that provides the least resistance.
  • If there is more than one generator being setup, the travelling of the circulating current does not use certain particular path. It may travel via variety of paths within the generator.
    • Because of this, electrical engineers and site managers will have problems in determining from which area these additional amps and current are coming from.
    • It can also be the cause of a dangerous and harmful situation.
  • Whenever current start to circulate
    • The action done by the circulating current may cause wires or generator parts to overheat.
    • This is because they are not designed for accessing the current flow created by these rogue currents.

    Always remember that circulating currents that can be found in your AC generator,

    • Can definitely cause your breakers to trip or even making its fuses to blow.
    • The problem can lead to operational down time where the circulating current would be able to overpower the circuit in which it has traveled.

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