First, the impact of new technical requirements for wind turbines on the dynamical behaviour of the power system was quantified. Especially the impact of different control systems of wind turbines on the power system dynamic were simulated and quantified. Secondly, the influences of the wind energy on frequency and voltage under steady state conditions were investigated. Wind generators generate electricity by tapping into the energy in the wind. Consequently, the turbine positioned upstream in the wind direction influences the wind speed at turbine locations on its downwind side. This shadowing effect from upstream turbines on other turbines further downstream is referred to as the wake effect and its impact on the output power of the wind farm was the final investigation.