A method for monitoring at least one rotor blade of a wind turbine includes implementing, via a controller, a control scheme for monitoring blade damage of the at least one rotor blade. The control scheme includes monitoring at least one electrical condition of a pitch system of the wind turbine. The method also includes converting the electrical condition(s) of the pitch system into a frequency domain. Further, the method includes determining one or more peaks of the frequency domain around a frequency component related to a natural frequency of the rotor blade. Moreover, the method includes determining a frequency deviation between the one or more peaks of the frequency domain and the frequency component related to the natural frequency of the rotor blade. As such, a frequency deviation outside of a predetermined frequency range is indicative of a rotor blade anomaly. Thus, the method includes implementing a control action when the frequency deviation is outside of the predetermined frequency range.

A method for monitoring at least one rotor blade of a wind turbine includes implementing, via a controller, a control scheme for monitoring blade damage of the at least one rotor blade. The control scheme includes monitoring at least one electrical condition of a pitch system of the wind turbine. The method also includes converting the electrical condition(s) of the pitch system into a frequency domain. Further, the method includes determining one or more peaks of the frequency domain around a frequency component related to a natural frequency of the rotor blade. Moreover, the method includes determining a frequency deviation between the one or more peaks of the frequency domain and the frequency component related to the natural frequency of the rotor blade. As such, a frequency deviation outside of a predetermined frequency range is indicative of a rotor blade anomaly. Thus, the method includes implementing a control action when the frequency deviation is outside of the predetermined frequency range.

Disclosed are a method and apparatus for detecting a yaw-to-wind abnormality. The method includes: acquiring a wind direction deviation angle within a specified time period; calculating a power performance index, wherein the power performance index is a dimensionless number used to characterize power generation performance of a wind turbine; determining an optimal wind direction deviation angle based on the power performance index; determining a current wind direction deviation angle according to probability distribution of the wind direction deviation angle; and if a difference between the optimal wind direction deviation angle and the current wind direction deviation angle is greater than a preset threshold, determining that a yaw-to-wind abnormality is detected. Compared with the related technology in which yaw-to-wind detection is performed through a power fitting curve, in the technical solution according to the embodiments of the present disclosure, a power index is directly used, which avoids the problem of poor power curve fitting effect and improves the accuracy of yaw-to-wind detection.

Disclosed are a method and apparatus for detecting a yaw-to-wind abnormality. The method includes: acquiring a wind direction deviation angle within a specified time period; calculating a power performance index, wherein the power performance index is a dimensionless number used to characterize power generation performance of a wind turbine; determining an optimal wind direction deviation angle based on the power performance index; determining a current wind direction deviation angle according to probability distribution of the wind direction deviation angle; and if a difference between the optimal wind direction deviation angle and the current wind direction deviation angle is greater than a preset threshold, determining that a yaw-to-wind abnormality is detected. Compared with the related technology in which yaw-to-wind detection is performed through a power fitting curve, in the technical solution according to the embodiments of the present disclosure, a power index is directly used, which avoids the problem of poor power curve fitting effect and improves the accuracy of yaw-to-wind detection.

A wind turbine (10) is disclosed having a hub (14) with electrical power therein and at least one blade (20) attached to the hub. The blade (20) has a blade root (21), a blade tip (26) and a down-wire (30) for the conduction of lightning current to the ground. The wind turbine (10) further has a blade electrical system (99) that takes electrical power from the hub (14) and transmits electrical power into the blade (20) to at least one area located between the blade root (21) and the blade tip (26). The blade electrical system (99) if formed by a power-transfer unit (100) having a power-driver unit (110), a power-conditioner unit (130) and a dielectric (120) separating the power-driver unit (110) and the power-conditioner unit (130). The power-driver unit (110) receives electrical power from the hub (14) and transmit the electrical power through the dielectric (120) to the power-conditioner unit (130). An electrical-power bus (200) is electrically attached to the power-conditioner unit (130) and extends into the blade (20). At least one powered unit (300) is provided which is electrically connected to, and electrically powered by, the electrical-power bus (200).

The invention provides a method for monitoring health state of blade root fastener, comprising the following steps: obtaining a sequence of acceleration signals representing the lateral vibration of the nacelle and a sequence of rotational speed signals representing the rotational speed of the rotor; analyzing the sequence of acceleration signals and the sequence of rotational speed signals to determine the amplitude of the nacelle at 2-time-frequncy of the rotational speed of the rotor; and determining the health state of the blade root fastener based on the amplitude. The invention also provides a system for monitoring the health state of the blade root fastener. Through the present invention, the health state of the blade root fastener can be determined with low cost and high precision, thereby improving the operation efficiency and operation safety of the wind turbine.

The invention provides a method for monitoring health state of blade root fastener, comprising the following steps: obtaining a sequence of acceleration signals representing the lateral vibration of the nacelle and a sequence of rotational speed signals representing the rotational speed of the rotor; analyzing the sequence of acceleration signals and the sequence of rotational speed signals to determine the amplitude of the nacelle at 2-time-frequncy of the rotational speed of the rotor; and determining the health state of the blade root fastener based on the amplitude. The invention also provides a system for monitoring the health state of the blade root fastener. Through the present invention, the health state of the blade root fastener can be determined with low cost and high precision, thereby improving the operation efficiency and operation safety of the wind turbine.

Provided herein are detection systems and related methods for detecting moving objects in an airspace surrounding the detection system. In an aspect, the moving object is a flying animal and the detection system comprises a first imager and a second imager that determines position of the moving object and for moving objects within a user selected distance from the system the system determines whether the moving object is a flying animal, such as a bird or bat. The systems and methods are compatible with wind turbines to identify avian(s) of interest in airspace around wind turbines and, if necessary, take action to minimize avian strike by a wind turbine blade.

Provided herein are detection systems and related methods for detecting moving objects in an airspace surrounding the detection system. In an aspect, the moving object is a flying animal and the detection system comprises a first imager and a second imager that determines position of the moving object and for moving objects within a user selected distance from the system the system determines whether the moving object is a flying animal, such as a bird or bat. The systems and methods are compatible with wind turbines to identify avian(s) of interest in airspace around wind turbines and, if necessary, take action to minimize avian strike by a wind turbine blade.

A method is provided for monitoring a pitch control system for a rotor blade of a wind turbine. The method comprises a step of receiving a blade pitch signal representative of a pitch position of the rotor blade, a step of determining a pitch deviation, based on the blade pitch signal and a blade pitch reference. If the determined pitch deviation exceeds a first pitch deviation threshold, a pitch deviation variable is increased by an amount that depends on the determined pitch deviation, the first pitch deviation threshold, and a duration of a time period during which the determined pitch deviation has been exceeding the first pitch deviation threshold. An error signal is provided when the increased pitch deviation variable exceeds a pitch deviation variable threshold.