Abstract: A rotor blade for a wind turbine is disclosed, comprising a root section, a tip section, a middle section, a blade skin, an electric heating arrangement having a heating strip, and a blade portion of an energy transfer arrangement being electrically connected to the heating arrangement. The blade further comprises a lightning arrangement having one lightning receptor mounted to the tip section and being electrically connected to the heating strip, wherein electrical energy of a lightning strike can be conducted from the lightning receptor into the heating strip. Furthermore, the lightning arrangement comprises a grounding device which is mounted to the root section, which is configured for conducting electrical energy received from the lightning receptor via the heating strip into a grounding arrangement. The heating strip has a width-thickness relation of at least 50:1, is flexible, arranged with the blade skin and extends over 50% of a total length of the rotor blade.

Abstract: A method (1000, 1001) for operating a wind turbine (100-100d) is disclosed. The wind turbine includes a rotor (106) with rotor blades (108), a power conversion system (118, 210, 234) mechanically connected with the rotor (106), a first subsystem (310 ), a second subsystem (320), and an internal electric power distribution system (300-301b, 321, 322) connectable with the first subsystem (310) and the second subsystem (320). During operating (1100) the wind turbine (100-100d) in a normal operating mode in which the power conversion system (118, 210, 234) converts input motive power into electrical output power (P), the method (1000) includes detecting (1200) an increased power demand of the first subsystem (310), and actively increasing (1300) an amount (P1) of electric power (Pint) flowing through the internal electric power distribution system (300-301b, 321, 322) to the first subsystem (310) if a power demand of the second subsystem (320) is at least reduced.

Abstract: It is provided a wind turbine and methods of operating a wind turbine as described herein.

Abstract: The present disclosure is directed to a system comprising a structure being prone to lightning strikes and icing, wherein the structure comprises a shielding arrangement electrically connected to a lightning arrangement, an electric heating arrangement connected to a power source for mitigating icing of the structure, and an electrical insulation arrangement being effectively provided between the shielding arrangement and the electric heating arrangement. A power source is configured for applying a predetermined amount of electric test- and/or maintenance-energy such that the electric test- and/or maintenance-energy is effectively present between the shielding arrangement and the electric heating arrangement. A determination device is electrically connected to the shielding arrangement and to the electric heating arrangement in a way that the shield-heating-voltage and/or the shield-heating-current being present between the shielding arrangement and the electric heating arrangement can be determined.

Abstract: Systems and methods for providing power to a blade pitch system in a wind turbine are provided. A blade pitch system can include one or more motors configured to pitch one or more blades of a wind turbine and a power source. The power source can include a plurality of energy storage devices coupled in series. The plurality of energy storage devices can be configured to provide power to the one or more motors during a power loss event. The power source can further include at least one bypass current device configured to allow a bypass current to provide power from at least one energy storage device to the one or more motors. The bypass current can be a current that bypasses one or more failed energy storage devices in the plurality of energy storage devices.

Abstract: The present disclosure is directed to an energy storage system including a power source and a power converter coupled to the power source. The power converter is configured to output power suitable for consumption in a utility grid. The energy storage system also includes an energy storage device configured to receive the power output from the power converter and a charge discharge converter coupled between the power converter and the energy storage device. The charge discharge converter is configured to control at least one of charging or discharging the energy storage device. Furthermore, the energy storage device includes a transformer coupled between the charge discharge converter and the power converter.

Abstract: Apparatus, systems, and methods are provided for determining remaining lifetime of a battery, such as a battery used to power a pitch drive system in a wind turbine. In one example implementation, a method can include controlling a discharge of the battery through a load. The method can include obtaining data indicative of a discharge voltage and a discharge current of the battery during discharge through the load. The method can include obtaining data indicative of a temperature associated with the battery during discharge through the load. The method can include determining data indicative of remaining lifetime of the battery as a function of the discharge voltage, discharge current, and the temperature. The method can include performing at least one control action based at least in part on the data indicative of remaining lifetime of the battery.

Abstract: A system and method for protecting an idling wind turbine power system from damage during loss of grid power. The wind turbine power system has a plurality of rotor blades. The method includes monitoring an incoming wind direction at the wind turbine power system. When the incoming wind direction is changing at a predetermined attack angle, the method also includes rotating at least one of the rotor blades of the wind turbine power system to a pitch angle that is offset from a feather position by a predetermined number of degrees to reduce and/or eliminate flutter phenomenon from occurring.

Abstract: A yaw system of a wind turbine having contingency autonomous control capabilities includes a plurality of yaw system components configured to change an angle of a nacelle of the wind turbine relative to an incoming wind direction. The plurality of yaw system components includes an auxiliary power supply comprising a brake power control device, a braking unit coupled to the brake power control device, at least two energy storage devices coupled to the braking unit, a plurality of yaw drive mechanisms communicatively coupled to the auxiliary power supply via a communication link, and a controller configured to implement a protective control strategy for the yaw system in response to one of the yaw system components experiencing a failure. Each of the yaw drive mechanisms includes a yaw power control device.

Abstract: Systems and methods for operating an energy storage system in a wind turbine system are provided. A wind turbine system can include a wind turbine, a power conversion system operably coupled to the wind turbine and an AC line bus, and an energy storage system coupled to the AC line bus. The energy storage system can include a transformer, a power converter, and an energy storage device and can be configured to store and provide power generated by the wind turbine. The method can include operating the wind turbine system to generate power, determining one or more operating parameters for the wind turbine system, determining an operating mode based on the one or more operating parameters, and controlling the wind turbine system based at least in part on the operating mode. Controlling the wind turbine can control a power flow into or out of the energy storage system.

Abstract: Systems and methods for operating an energy storage system in a doubly fed induction generator wind turbine system are provided. An energy storage system can include a transformer configured to transform AC power from a first voltage to AC power at a second voltage and a bi-directional AC to DC power converter coupled to the transformer. The bi-directional AC to DC power converter can be configured to convert the AC power at the second voltage to a DC power. The energy storage system can further include an energy storage device coupled to the bi-directional AC to DC power converter. The energy storage system can be configured to receive power generated by a rotor of the DFIG via an AC line bus. The energy storage device can be configured to store the power received by the energy storage system.

Abstract: The present disclosure is directed to an energy storage system including a power source and a power converter coupled to the power source. The power converter is configured to output power suitable for consumption in a utility grid. The energy storage system also includes an energy storage device configured to receive the power output from the power converter and a charge discharge converter coupled between the power converter and the energy storage device. The charge discharge converter is configured to control at least one of charging or discharging the energy storage device. Furthermore, the energy storage device includes a transformer coupled between the charge discharge converter and the power converter.

Abstract: A yaw system of a wind turbine having contingency autonomous control capabilities includes a plurality of yaw system components configured to change an angle of a nacelle of the wind turbine relative to an incoming wind direction. The plurality of yaw system components includes an auxiliary power supply comprising a brake power control device, a braking unit coupled to the brake power control device, at least two energy storage devices coupled to the braking unit, a plurality of yaw drive mechanisms communicatively coupled to the auxiliary power supply via a communication link, and a controller configured to implement a protective control strategy for the yaw system in response to one of the yaw system components experiencing a failure. Each of the yaw drive mechanisms includes a yaw power control device.

Abstract: Apparatus, systems, and methods are provided for determining remaining lifetime of a battery, such as a battery used to power a pitch drive system in a wind turbine. In one example implementation, a method can include controlling a discharge of the battery through a load. The method can include obtaining data indicative of a discharge voltage and a discharge current of the battery during discharge through the load. The method can include obtaining data indicative of a temperature associated with the battery during discharge through the load. The method can include determining data indicative of remaining lifetime of the battery as a function of the discharge voltage, discharge current, and the temperature. The method can include performing at least one control action based at least in part on the data indicative of remaining lifetime of the battery.

Abstract: Systems and methods for providing power to a blade pitch system in a wind turbine are provided. A blade pitch system can include one or more motors configured to pitch one or more blades of a wind turbine and a power source. The power source can include a plurality of energy storage devices coupled in series. The plurality of energy storage devices can be configured to provide power to the one or more motors during a power loss event. The power source can further include at least one bypass current device configured to allow a bypass current to provide power from at least one energy storage device to the one or more motors. The bypass current can be a current that bypasses one or more failed energy storage devices in the plurality of energy storage devices.

Abstract: Systems and methods for operating an energy storage system in a doubly fed induction generator wind turbine system are provided. An energy storage system can include a transformer configured to transform AC power from a first voltage to AC power at a second voltage and a bi-directional AC to DC power converter coupled to the transformer. The bi-directional AC to DC power converter can be configured to convert the AC power at the second voltage to a DC power. The energy storage system can further include an energy storage device coupled to the bi-directional AC to DC power converter. The energy storage system can be configured to receive power generated by a rotor of the DFIG via an AC line bus. The energy storage device can be configured to store the power received by the energy storage system.

Abstract: Systems and methods for operating an energy storage system in a wind turbine system are provided. A wind turbine system can include a wind turbine, a power conversion system operably coupled to the wind turbine and an AC line bus, and an energy storage system coupled to the AC line bus. The energy storage system can include a transformer, a power converter, and an energy storage device and can be configured to store and provide power generated by the wind turbine. The method can include operating the wind turbine system to generate power, determining one or more operating parameters for the wind turbine system, determining an operating mode based on the one or more operating parameters, and controlling the wind turbine system based at least in part on the operating mode. Controlling the wind turbine can control a power flow into or out of the energy storage system.

Abstract: Systems and methods to provide for the controlled braking of a generator (e.g., a doubly-fed induction generator (DFIG)) in a wind power system are provided. In one example implementation, a method for braking a wind-driven doubly fed induction generator can include: receiving, by one or more control devices, a command to brake a wind-driven doubly fed induction generator; and generating, by the one or more control devices, a pulse width modulation scheme for the rotor side converter to provide a rotor side output to a rotor of the doubly-fed induction generator. The rotor side output includes a non-zero DC component and an AC component. The method includes controlling, by the one or more control devices, the rotor side converter in accordance with the pulse width modulation scheme. The non-zero DC component of the rotor side output can reduce a speed of rotation of the wind-driven doubly fed induction generator.

Abstract: Systems and methods to provide for the controlled braking of a generator (e.g., a doubly-fed induction generator (DFIG)) in a wind power system are provided. In one example implementation, a method for braking a wind-driven doubly fed induction generator can include: receiving, by one or more control devices, a command to brake a wind-driven doubly fed induction generator; and generating, by the one or more control devices, a pulse width modulation scheme for the rotor side converter to provide a rotor side output to a rotor of the doubly-fed induction generator. The rotor side output includes a non-zero DC component and an AC component. The method includes controlling, by the one or more control devices, the rotor side converter in accordance with the pulse width modulation scheme. The non-zero DC component of the rotor side output can reduce a speed of rotation of the wind-driven doubly fed induction generator.

Abstract: In one embodiment, an energy storage system includes a plurality of energy storage banks. The plurality of energy storage banks include a first set of one or more energy storage banks and a second set of one or more energy storage banks. The first set of the energy storage banks is associated with a faster charge/discharge rate relative to the second set of energy storage banks. The energy storage system includes at least one control device that is configured to control the first set of energy storage banks to accept or discharge energy in response to fluctuations in a power signal associated with a first frequency; and is further configured to control the second set of energy storage banks to accept or discharge energy in response to fluctuations in the power signal associated with a second frequency. The first frequency is greater than the second frequency.