Provided is a method of generating a converter control signal for a generator side converter portion, in particular of a wind turbine, being coupled to a generator, in particular a permanent magnet synchronous machine, the method including: deriving at least one harmonic torque reference, in particular based on a harmonic torque demand and/or a torque indicating feedback signal; deriving at least one harmonic flux reference, in particular based on a harmonic stator voltage demand and/or a stator voltage indicating feedback signal; adding all of the at least one harmonic torque reference to a fundamental torque reference and subtracting an estimated generator torque to derive a torque error; adding all of the at least one harmonic flux reference to a fundamental flux reference and subtracting an estimated generator flux to derive a flux error; and deriving the converter control signal based on the torque error and the flux error.

An arrangement for determining an operation parameter reference for controlling a generator side converter portion coupled to a generator is provided, including: at least one arithmetic element configured to derive at least one harmonic current error by subtracting a generator output current from at least one harmonic current reference; at least one harmonic current controller configured to determine at least one harmonic reference current deviation based on the harmonic current error; another arithmetic element configured to derive a fundamental current error by subtracting the generator output current from a sum of a fundamental current reference and the at least one harmonic current reference; still another arithmetic element configured to determine a modified fundamental current error as a sum of the fundamental current error and the harmonic reference current deviation; a fundamental current controller adapted to determine the operation parameter reference based on the modified fundamental current error.

A method for operating an asynchronous inverter-based resource connected to a power grid as a virtual synchronous machine to provide grid-forming control thereof includes receiving a frequency reference command and/or a voltage reference command. The method also includes determining at least one power reference signal for the inverter-based resource based on the frequency reference command and/or the voltage reference command. Further, the method includes generating at least one current vector using the power reference signal(s). Moreover, the method includes determining one or more voltage control commands for the inverter-based resource using the at least one current vector. In addition, the method includes controlling the inverter-based resource based on the one or more voltage control commands such that the inverter-based resource actively participates in controlling at least one of voltage and frequency at a point of interconnection between the inverter-based resource and the power grid in a closed loop manner.

A method for providing grid-forming control of a double-fed wind turbine generator connected to an electrical grid includes receiving at least one control signal associated with a desired total power output or a total current output of the double-fed wind turbine generator. The method also includes determining a contribution of at least one of power or current from the line-side converter to the desired total power output or to the total current output of the double-fed wind turbine generator, respectively. The method also includes determining a control command for a stator of the double-fed wind turbine generator based on the contribution of at least one of the power or the current from the line-side converter and the at least one control signal. Further, the method includes using the control command to regulate at least one of power or current in the stator of the double-fed wind-turbine generator.

Provided are a motor rotation angle measurement device and method. The device may comprise: a signal conditioning circuit, configured to receive a three-phase output voltage of a motor and separately generate three square-wave signals; and a processor, configured to generate a six-multiplying frequency pulse whenever jumping of any one of the three square-wave signals, is detected in a rotation period of a motor, generate compensation pulses between the current six-multiplying frequency pulse and a next six-multiplying frequency pulse based on a time interval between the current six-multiplying frequency pulse and a previous six-multiplying frequency pulse and a preset compensation subdivision coefficient k, and accumulate the number of the compensation pulses, wherein the number of the compensation pulses is related to the rotation angle of the motor.

A method and a wind turbine are provided. The wind turbine includes a gearless generator that is a synchronous generator and includes a stator and a generator rotor. The wind turbine includes a generator filter with modifiable filter properties that is coupled to the stator and configured to filter a stator current. The wind turbine includes a filter controller configured to control the generator filter.

Provided is controller for a wind turbine including a power controller unit for controlling a power output of an electric generator included in the wind turbine. The power controller unit operates the electric generator according to a speed reference value and a power reference value, the speed reference value and a power reference value being chosen along a linear operating trajectory in a power vs speed graph, the linear operating trajectory including a point corresponding to the nominal power and the nominal generator speed. The power controller unit includes a slider command for selecting the angular position of the linear operating trajectory in the power vs speed graph.

A method of operating a wind turbine is provided. A controller is configured to activate or deactivate each of two or more distinct control features, each control feature changing the operating characteristic of the wind turbine and having an impact on at least one of lifetime and energy production . The method includes determining a type of optimization parameter and an optimization target for the optimization parameter, wherein the optimization parameter is related to at least one of lifetime or energy production of the wind turbine. The method further performs one or more optimization steps, wherein each optimization step is performed for a different combination of activation states of the two or more control features. Based on the one or more optimization steps, an optimal combination of activation states of the two or more control features for which the estimated optimization parameter achieves the optimization target is determined.

A wind turbine having an electrical power generation assembly and a control device for controlling the power generation assembly is provided, the electrical power generation assembly including a generator, at least one converter connected to the generator, and an overheating detection device, wherein the overheating detection device includes—at least two temperature sensing elements at different positions of the power generation assembly, wherein the temperature sensing elements are connected in series along a signal line to provide a common sensor signal and are each adapted to indicate the exceeding of a respective critical temperature at their position in the common sensor signal, and—a detection unit for evaluating the common sensor signal, which is connected to the signal line.

A method for operating an electric machine (in particular a wind turbine) having a generator with a rotor and a stator is provided. The method includes: i) evaluating an active damping applied to the electric machine, ii) estimating a damping criterion from the evaluated applied active damping, and iii) shifting a dynamic capacity curve towards a maximum allowed level. The maximum allowed level is based on the damping criterion and a first operation criterion and/or a second operation criterion. Furthermore, the dynamic capacity curve is a dynamic power capacity curve or a dynamic torque capacity curve.