Abstract: The present invention relates to an Electro-Thermal Heating element for a wind turbine blade comprising an electrically conductive resistive material; two active busbars for supplying electrical power to the electrically conductive resistive material; and at least one dummy busbar at a predetermined spacing between the two active busbars on the electrically conductive resistive material. The present invention is also directed to a method of repair of the Electro-Thermal Heating Element.

Abstract: The present invention relates to a method of controlling an electro-thermal heating system in a wind turbine blade, comprising measuring a supply voltage to the electro-thermal heating system, determining a duration of a variable time based enforced off period based on the measured supply voltage, and inserting the variable time based enforced off period between subsequent switching duty cycles that controls the electro-thermal heating system. The present invention also relates to a wind turbine that comprises one or more wind turbine blades wherein each wind turbine blade comprises an electro-thermal heating system and a processor adapted to perform the method.

Abstract: A method of inspecting a wind turbine blade. The wind turbine blade comprises an electro-thermal heating element and a surface protection layer. The method comprises: exposing a test point of the electro-thermal heating element; contacting the test point to establish an electrical connection between the test point and a sensor; and electrically connecting the sensor to the surface protection layer. The sensor is operated to measure a resistance value indicative of an electrical resistance between the test point and the surface protection layer. The resistance value is analysed to determine a condition of the wind turbine blade. The invention provides a method of inspecting a wind turbine blade which enables damage or defects to be detected which may be difficult to detect by visual inspection or traditional non-destructive testing techniques. For instance, the resistance value may give an indication of the presence of an electrical short between the heating element and the surface protection layer.

Abstract: The present invention relates to a method of identifying an electrical contact fault in a wind turbine blade electrical heating system, comprising inserting a predetermined enforced off cycle between or within a switching duty cycle, wherein the switching duty cycle controls the switching of one or more electrical contacts in the electrical heating system, measuring a current consumption during the predetermined enforced off cycle, determining if the measured current consumption exceeds a predetermined threshold, and wherein if the measured current consumption exceeds the predetermined threshold shutting down at least part of the electrical heating system. The present invention also relates to a wind turbine with one or more wind turbine blades that can identify an electrical contact fault.

Abstract: The present invention relates to a method of controlling an electro-thermal heating system in a wind turbine blade, comprising measuring a supply voltage to the electro-thermal heating system, determining a duration of a variable time based enforced off period based on the measured supply voltage, and inserting the variable time based enforced off period between subsequent switching duty cycles that controls the electro-thermal heating system. The present invention also relates to a wind turbine that comprises one or more wind turbine blades wherein each wind turbine blade comprises an electro-thermal heating system and a processor adapted to perform the method.

Abstract: The present invention relates to a method of identifying an electrical contact fault in a wind turbine blade electrical heating system, comprising inserting a predetermined enforced off cycle between or within a switching duty cycle, wherein the switching duty cycle controls the switching of one or more electrical contacts in the electrical heating system, measuring a current consumption during the predetermined enforced off cycle, determining if the measured current consumption exceeds a predetermined threshold, and wherein if the measured current consumption exceeds the predetermined threshold shutting down at least part of the electrical heating system. The present invention also relates to a wind turbine with one or more wind turbine blades that can identify an electrical contact fault.

Abstract: The present invention relates to an Electro-Thermal Heating element for a wind turbine blade comprising an electrically conductive resistive material; two active busbars for supplying electrical power to the electrically conductive resistive material; and at least one dummy busbar at a predetermined spacing between the two active busbars on the electrically conductive resistive material. The present invention is also directed to a method of repair of the Electro-Thermal Heating Element.

Abstract: The invention relates to a wind turbine blade oscillation preventer comprising an aperture and a sleeve and having a peripheral extent and a longitudinal extent, the preventer being configured for removable application over a wind turbine blade and configured to extend longitudinally thereover and peripherally thereabout; the preventer having a non-aerodynamic exterior surface which exhibits a rough surface capable of disrupting smooth or laminar airflow over a substantial portion of the longitudinal and peripheral extent of the sleeve when the preventer is in place on a wind turbine blade. The preventer further comprises a smooth interior surface extending along a substantial portion of the longitudinal extent of the sleeve. The invention also relates to a method of application of a blade oscillation preventer over wind turbine blades which comprise serrations at a trailing edge thereof.

Abstract: The invention relates to a wind turbine blade oscillation preventer comprising an aperture and a sleeve and having a peripheral extent and a longitudinal extent, the preventer being configured for removable application over a wind turbine blade and configured to extend longitudinally thereover and peripherally thereabout; the preventer having a non-aerodynamic exterior surface which exhibits a rough surface capable of disrupting smooth or laminar airflow over a substantial portion of the longitudinal and peripheral extent of the sleeve when the preventer is in place on a wind turbine blade. The preventer further comprises a smooth interior surface extending along a substantial portion of the longitudinal extent of the sleeve. The invention also relates to a method of application of a blade oscillation preventer over wind turbine blades which comprise serrations at a trailing edge thereof.