Method for controlling a wind turbine system, the wind turbine system including a power conversion assembly for converting electrical power into a converted electrical power, wherein the wind turbine system is adapted to operate at a rated power, the method comprising: controlling the wind turbine system adaptively depending on whether the wind turbine system operates below its rated power or whether the wind turbine system operates at or above its rated power, wherein a power in the wind turbine system is monitored at different operating points and the wind turbine system is subsequently controlled in response to the monitoring, wherein the operating points depend on whether the wind turbine system operates below its rated power or at/above its rated power, wherein the method comprises: a) monitoring a power extraction parameter while the wind turbine system operates below its rated power, wherein the power extraction parameter is indicative of the power extracted by the wind turbine system from the wind prior to being converted in the power conversion assembly; b) controlling one or more operational variables of the wind turbine system in response to monitoring the power extraction parameter, while the wind turbine system operates below its rated power; c) monitoring the output power of the wind turbine system while the wind turbine system operates at or above its rated power, wherein the output power includes power supplied by the wind turbine system to an electric grid; and, d) controlling one or more operational variables of the wind turbine system in response to monitoring the output power, while the wind turbine system operates at or above its rated power, wherein the one or more operational variables of the wind turbine system which are controlled in response to monitoring the output power, and the one or more operational variables which are controlled in response to monitoring the power extraction parameter are the same operational variables, wherein monitoring the output power of the wind turbine system comprises: monitoring the output power of the wind turbine system at a primary and/or secondary side of a transformer included in the wind turbine system, wherein the transformer is adapted for transmitting power generated by the wind turbine system to the electric grid. controlling the wind turbine system adaptively depending on whether the wind turbine system operates below its rated power or whether the wind turbine system operates at or above its rated power, wherein a power in the wind turbine system is monitored at different operating points and the wind turbine system is subsequently controlled in response to the monitoring, wherein the operating points depend on whether the wind turbine system operates below its rated power or at/above its rated power, wherein the method comprises: a) monitoring a power extraction parameter while the wind turbine system operates below its rated power, wherein the power extraction parameter is indicative of the power extracted by the wind turbine system from the wind prior to being converted in the power conversion assembly; b) controlling one or more operational variables of the wind turbine system in response to monitoring the power extraction parameter, while the wind turbine system operates below its rated power; c) monitoring the output power of the wind turbine system while the wind turbine system operates at or above its rated power, wherein the output power includes power supplied by the wind turbine system to an electric grid; and, d) controlling one or more operational variables of the wind turbine system in response to monitoring the output power, while the wind turbine system operates at or above its rated power, wherein the one or more operational variables of the wind turbine system which are controlled in response to monitoring the output power, and the one or more operational variables which are controlled in response to monitoring the power extraction parameter are the same operational variables, a) monitoring a power extraction parameter while the wind turbine system operates below its rated power, wherein the power extraction parameter is indicative of the power extracted by the wind turbine system from the wind prior to being converted in the power conversion assembly; b) controlling one or more operational variables of the wind turbine system in response to monitoring the power extraction parameter, while the wind turbine system operates below its rated power; c) monitoring the output power of the wind turbine system while the wind turbine system operates at or above its rated power, wherein the output power includes power supplied by the wind turbine system to an electric grid; and, d) controlling one or more operational variables of the wind turbine system in response to monitoring the output power, while the wind turbine system operates at or above its rated power, wherein the one or more operational variables of the wind turbine system which are controlled in response to monitoring the output power, and the one or more operational variables which are controlled in response to monitoring the power extraction parameter are the same operational variables, wherein monitoring the output power of the wind turbine system comprises: monitoring the output power of the wind turbine system at a primary and/or secondary side of a transformer included in the wind turbine system, wherein the transformer is adapted for transmitting power generated by the wind turbine system to the electric grid.