Abstract: 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.

Abstract: The present invention relates to a method for operating a converter system of a wind turbine, wherein the converter system includes converter modules capable of converting electric power produced by a generator to electric power applicable to a utility grid. The converter modules include generator inverters and grid inverters. The method determines the enabling/disabling of the converter modules in response to a parameter related to the variable amount of electric power being produced by the generator. Advantages of the present invention are optimisation of power efficiency of the converter modules and improved reliability of the converter modules. Another advantage is the capability of fast enabling and disabling of the converter modules.

Abstract: The present invention relates to a method for operating a converter system of a wind turbine, wherein the converter system includes converter modules capable of converting electric power produced by a generator to electric power applicable to a utility grid. The converter modules include generator inverters and grid inverters. The method determines the enabling/disabling of the converter modules in response to a parameter related to the variable amount of electric power being produced by the generator. Advantages of the present invention are optimisation of power efficiency of the converter modules and improved reliability of the converter modules. Another advantage is the capability of fast enabling and disabling of the converter modules.

Abstract: The present invention relates to a method for operating a converter system of a wind turbine, wherein the converter system includes converter modules capable of converting electric power produced by a generator to electric power applicable to a utility grid. The converter modules include generator inverters and grid inverters. The method determines the enabling/disabling of the converter modules in response to a parameter related to the variable amount of electric power being produced by the generator. Advantages of the present invention are optimisation of power efficiency of the converter modules and improved reliability of the converter modules. Another advantage is the capability of fast enabling and disabling of the converter modules.

Abstract: The present invention relates to a method for operating a converter system of a wind turbine, wherein the converter system includes converter modules capable of converting electric power produced by a generator to electric power applicable to a utility grid. The converter modules include generator inverters and grid inverters. The method determines the enabling/disabling of the converter modules in response to a parameter related to the variable amount of electric power being produced by the generator. Advantages of the present invention are optimisation of power efficiency of the converter modules and improved reliability of the converter modules. Another advantage is the capability of fast enabling and disabling of the converter modules.

Abstract: Method for commutation of a brushless motor being supplied with electrical energy from a DC intermediary circuit via a multi-phase inverter, by which a first current and a second current value are determined and the length of a commutation interval is set in dependence of these current values. With motors being exposed to heavily varying load torques during one rotation, e.g. motors driving a compressor, a stable operation must be reached. For this purpose a correction value is added to the pre-set commutation interval determined by the speed of the motor, said correction value being the result of the difference of the actual value of the intermediary circuit current and a filtered and delayed value of the intermediary circuit current, multiplied by a weighting factor.