Method, program and computer-readable medium for avoiding an unintended fall of a blade of a wind turbine, and energy conversion system

An energy conversion system of a wind turbine, the energy conversion system comprising:

• a rotating electrical machine;
• at least one machine-side converter coupled to the rotating electrical machine;
• at least one direct current link (DC-link) coupled to the at least one machine-side converter;
• at least one grid-side converter, which is configured to couple the DC-link to an electrical grid;
• and
• a master controller for avoiding an unintended fall of a blade of the wind turbine, when the blade or another blade of the wind turbine is arranged at a rotor hub of the wind turbine, the wind turbine comprising the rotor hub, the rotating electrical machine mechanically coupled to the rotor hub, the at least one machine-side converter electrically coupled to the rotating electrical machine and comprising several semiconductor switches, the wind turbine further comprising a direct current link (DC-link) electrically coupled to the at least one machine-side converter, the master controller configured to:
• generate a short circuit at the DC-link by activating all of the semiconductor switches at a same time.