  We investigate the collective phase dynamics in conventional long Josephson
junction (LJJ) stacks and in layered superconductors, exhibiting intrinsic LJJ
behaviors. Using a theoretical model which accounts for both the magnetic
induction effect and the breakdown of local charge neutrality (i.e., charging
effect), we show that the collective motion of Josephson vortices, including
the dispersion of Josephson plasma mode and the Swihart-type velocity, in an
intrinsic LJJ stack such as Bi$_2$Sr$_2$CaCu$_2$O$_{8+y}$ (BSCCO) is
significantly modified from those in a conventional LJJ stack. In BSCCO, the
strength of the charging effect $\alpha$ is small (i.e., $\alpha \sim
0.1-0.4$), but it leads to notable changes in collective phase dynamics,
including changes to the stability condition. Also, we show that splitting of
the supercurrent branch in the resistive state is due to collective motion of
Josephson vortices. The width of spread of these sub-branches in the linear
current-voltage regime depends on $\alpha$, suggesting another way to measure
the charging effect in BSCCO.
