Abstract: A method for operating a wind farm comprising several wind turbines that are connected to an internal grid of the wind farm is disclosed. In the method, during a mains failure the electrical consumers of the wind turbines are supplied with electrical energy by a mains replacement supply unit. Each electrical consumer of the wind turbines is assigned to one of at least two groups and according to the group assignment is always switched on by an operation control unit when required, or only switched on if there is a sufficient power reserve. The wind farm is designed to carry out the method.

Abstract: A wind turbine having a generator for generating electrical energy and a transformer is disclosed. The transformer is designed to receive electrical energy from the generator on a secondary side and to discharge said electrical energy again on a primary side at a higher voltage. The wind turbine also comprises a temperature monitoring means for the transformer. The voltage supply to the temperature monitoring means is fed from the primary side of the transformer. The temperature monitoring means is thereby independent of the control system of the wind turbine. The temperature monitoring means reduces the risk of the transformer overheating. A method for operating such a wind turbine is also disclosed.

Abstract: A wind turbine having a generator for generating electrical energy and a transformer is disclosed. The transformer is designed to receive electrical energy from the generator on a secondary side and to discharge said electrical energy again on a primary side at a higher voltage. The wind turbine also comprises a temperature monitoring means for the transformer. The voltage supply to the temperature monitoring means is fed from the primary side of the transformer. The temperature monitoring means is thereby independent of the control system of the wind turbine. The temperature monitoring means reduces the risk of the transformer overheating. A method for operating such a wind turbine is also disclosed.

Abstract: A method for operating a wind farm comprising several wind turbines that are connected to an internal grid of the wind farm is disclosed. In said method, during a mains failure the electrical consumers of the wind turbines are supplied with electrical energy by a mains replacement supply unit. Each electrical consumer of the wind turbines is assigned to one of at least two groups and according to the group assignment is always switched on by an operation control unit when required, or only switched on if there is a sufficient power reserve. The wind farm is designed to carry out said method.