Abstract: A wind energy power plant optical vibration sensor is described, using two light sources 15, 16 that emit light at different respective frequencies. The light from the first light source falls on a surface 44 of the wind energy power plant at a detection site. Movements in the surface result in changes to the phase of the light reflected back from the surface which can be detected by mixing the first light with the light emitted from the second light source. The difference in frequencies between the two light sources results in a beating of the resulting interference signal, whereas movements in the sensor surface result in changes in the phase timing and frequency of the beats.

Abstract: The invention comprises a wind turbine having an optical wind sensor 10. The optical wind sensor generates one or more multiple beams of light 42, each of which forms a sensor beam pointing along a sensor axis. Where more than one sensor beam is used the beams are arranged so that the different sensor axes lie at least partly orthogonal to each other, allowing the wind direction 40 to be detected for any direction of wind. Each multiple sensor beam comprises at least two individual sensor beams having different respective wavelengths of light. The different colour of the individual light beams allows the sensor system to detect which of the light beams is triggered first when matter in the wind passes through the beam and reflects light back to light collecting device.

Abstract: Broad band optical strain sensing systems for a wind turbine. The strain sensing system includes an optical fiber with an input at one end and an output at the opposite end. The optical fiber is provided with Bragg sensors between the input and the output. By injecting light at the input of the fiber, measuring the spectral intensity distribution of at the output of the fiber and determining spectral locations of intensity notches in the spectral intensity distribution, it is possible to determine strain values at the locations of the Bragg sensors from the transmitted light.

Abstract: Broad band optical strain sensing systems for a wind turbine. The strain sensing system includes an optical fiber with an input at one end and an output at the opposite end. The optical fibre is provided with Bragg sensors between the input and the output. By injecting light at the input of the fiber, measuring the spectral intensity distribution of at the output of the fiber and determining spectral locations of intensity notches in the spectral intensity distribution, it is possible to determine strain values at the locations of the Bragg sensors from the transmitted light.

Abstract: The invention relates to a broad band optical strain sensing system for a wind turbine. The strain sensing system includes an optical fiber with an input at one end and an output at the opposite end. The optical fiber is provided with Bragg sensors between the input and the output. By injecting light at the input of the fiber, measuring the spectral intensity distribution of at the output of the fiber and determining spectral locations of intensity notches in the spectral intensity distribution, it is possible to determine strain values at the locations of the Bragg sensors from the transmitted light.

Abstract: The invention relates a wind turbine rotor. The rotor comprises at least one wind turbine blade, at least one image capturing device, and one or more markers arranged on the blade so that the at least one image capturing device may detect the position of the markers. The invention further relates to a wind turbine and use thereof.

Abstract: The invention relates to a broad band optical strain sensing system for a wind turbine. The strain sensing system includes an optical fibre with an input at one end and an output at the opposite end. The optical fibre is provided with Bragg sensors between the input and the output. By injecting light at the input of the fibre, measuring the spectral intensity distribution of at the output of the fibre and determining spectral locations of intensity notches in the spectral intensity distribution, it is possible to determine strain values at the locations of the Bragg sensors from the transmitted light.

Abstract: The invention relates to a method for sensing strain in a component in a wind turbine comprising an optical sensor system. The method comprises the step of inputting a optical signal into at least one optical fibre of said sensor system comprising one or more fibre Bragg grating sensors. Further, the method comprises the step of measuring the transmitted optical signals of said one or more sensors with at least one light detector connected to the other end of said at least one optical fibre, and processing the measured signals in a control unit in order to establish a value of the strain for the component. The invention also relates to an optical strain sensing system for a component in a wind turbine and uses hereof.