This invention relates to a wind turbine having an additional mass each placed between a mounting end and a free end of at least two rotor blades. This invention further relates to a method for controlling a wind turbine with a pitch system for pitching a blade in a pitch angle and with blades with a mass for increased inertia, which wind turbine is operated in a normal operation mode in which a generator has a generator speed at a generator torque, and which wind turbine is to remain electrically coupled to a grid during a low voltage condition and with supplied current specifications, torque reference, power references, or according to a grid code.