Control of rotor blade heaters
Iced wind turbine blades reduce the aerodynamic performance and thus the yield of wind turbines by aero losses at the rotor blade surface.
In icy conditions, a shutdown of the wind turbine is required for safety reasons. Ice detection systems are required for many sites.
More full-load hours through ice-free blades
To avoid icing, there are various passive and active concepts. A proven way to avoid icing on the rotor blade of a wind turbine is to heat the rotor blade. This results in more full-load hours and therefore provides an economic benefit..
Precise activation of rotor blade heating absolutely necessary
However, the heating systems require significant electrical energy, in some cases several hundred kW per wind turbine. Thus, the rotor blade heating consumes at some operational points more energy than generated by the wind turbine: The use of a rotor blade heating is detrimental.
To keep the power consumption of the heating system as low as possible, precise control is necessary. Due to the large lengths of modern blades, large parts of the heating energy are dissipated over the surface: The heating capacity of a system must be correspondingly high in order to enable heating of the rotor blade tip where the most ice attaches due to high wind speeds and where ice has the most impact on aerodynamics.
Passive sensors for efficiency monitoring of de-icing
If the heating power is adjusted sufficiently high, ice can be melted off during operation or ice accumulation can be avoided. Ice on the rotor blade changes the natural frequencies of the rotor blade. Vibration sensors in the rotor blade tip allow detection of very small masses of ice and can therefore be used for efficient monitoring of de-icing systems. fos4X provides fiber optic vibration sensors for installation in the rotor blade.