  We analyze quasiperiodic partially synchronous states in an ensemble of
Stuart-Landau oscillators with global nonlinear coupling. We reveal two types
of such dynamics: in the first case the time-averaged frequencies of
oscillators and of the mean field differ, while in the second case they are
equal, but the motion of oscillators is additionally modulated. We describe
transitions from the synchronous state to both types of quasiperiodic dynamics,
and a transition between two different quasiperiodic states. We present an
example of a bifurcation diagram, where we show the borderlines for all these
transitions, as well as domain of bistability.
