When excitation is increased (over excitation), the synchronous generator operates at?

Synchronous generator will operate at lagging power factor.

operates at lagging power factor

Ans.3 because for a given fixed out put load, an increse in excitation of the generator will result in increased lagging pf.

When the excitation feeding to Generator is increased more than normal leve to be over excitation. Then Synchronous Generator operates at Lagging Power Factor.

If excitation is increased, E cosδ > V, the generator delivers reactive power to the load and operates at lagging power factor.

Over excited syn. generator operates at Lagging power factor

operates in lagging power factor