Vacuum interrupter in GIS

Loads of people can. Try this.

<...What are its advantages for its application in generator circuit breaker?...>

Compared to what else?

These type breakers are used in high and medium AC voltage switchgear...

https://en.wikipedia.org/wiki/Switchgear

https://switchgearcontent.com/2019/08/28/829/hv-vacuum-circuit-breaker-in-gis/

There is little to no advantage other than size for a generator circuit breaker. They are much more useful in applications with significant numbers of operations per day. Surge arresters are used to reduce voltage excursions that come with the sharp interruption of current typically associated with vacuum interrupters. Air break equipment provides a softer interruption that applies less stress to the stator winding insulation. Air break equipment is also a lower technical level for maintenance & repair, which sometimes is an advantage for the owning facility.

do u mean to say that gis with vacuum interrupters are more useful in generators with more number of interruptions per day? In my thinking, number of generator operations per day can not be guaranteed...is there any specific case where number of generator interruptions will be more? In a bad day with system collapse, there may be more no of vacuum interrupters per day while on some good days, there may not be any.

Is this a front-end design problem or a standardisation one?

Is there no established procedure within the facility for doing this?

I would not expect a medium voltage generator breaker to operate more than once a month, maybe less. Also, the stress on the interruption mechanism is much lower on a generator application than for an induction motor. If it was mine, I’d want to have a really good reason to apply a vacuum interrupter, because they are a risk to the machine insulation system.

You did not take that away from my first comment?

In mission critical operations, always design for the worst case scenario.

Is there no applicable and appropriate electrical standard locally that can be consulted?