In this paper, periodic power pulsations from a three-bladed wind turbine are analyzed. The influence of wind shear, wind speed, turbulence intensity, rotor position and tower oscillation is investigated. No clear dependence between the periodic power components and the wind shear or turbulence intensity has been verified, The investigated turbine sometimes produces large power pulsations at the tower resonance frequency, These occur when the turbine oscillates in the sideways direction of the nacelle.