  We study the dynamic vortex Mott transition in two-dimensional
superconducting arrays in a magnetic field with $f$ flux quantum per plaquette.
The transition is induced by external driving current and thermal fluctuations
near rational vortex densities set by the value of $f$, and has been observed
experimentally from the scaling behavior of the differential resistivity.
Recently, numerical simulations of interacting vortex models have demonstrated
this behavior only near fractional $f$. A fine-grid vortex model is introduced,
which allows to consider both the cases of fractional and integer $f$. The
critical behavior is determined from a scaling analysis of the current-voltage
relation and voltage correlations near the transition, and by Monte Carlo
simulations. The critical exponents for the transition near $f=1/2$ are
consistent with the experimental observations and previous numerical results
from a standard vortex model. The same scaling behavior is obtained for $f=1$,
in agreement with experiments. However, the estimated correlation-length
exponent indicates that even at integer $f$, the critical behavior is not of
mean-field type.
