  In this work, the first nonlinear particle-in-cell simulations carried out in
a stellarator with the global gyrokinetic code EUTERPE using realistic plasma
parameters are reported. Several studies are conducted with the aim of enabling
reliable nonlinear simulations in stellarators with this code. First, EUTERPE
is benchmarked against ORB5 in both linear and nonlinear settings in a tokamak
configuration. Next, the use of noise control and stabilization tools, a
Krook-type collision operator, markers weight smoothing and heating sources is
investigated. It is studied in detail how these tools influence the linear
growth rate of instabilities in both tokamak and stellarator geometries and
their influence on the linear zonal flow evolution in a stellarator. Then, it
is studied how these tools allow improving the quality of the results in a set
of nonlinear simulations of electrostatic turbulence in a stellarator
configuration.
  Finally, these tools are applied to a W7-X magnetic configuration using
experimental plasma parameters.
