System reduces costs and increases reliability
The innovative Nordex Advanced Anti-icing System comprises
a sensor positioned on the nacelle and heating elements
integrated in the rotor blade, which work on the principle of
electrical resistance heaters. The heating elements are each
composed of many individual segments and are positioned close
to the surface. Hence – unlike hot-air heaters – they do not heat
the entire blade structure from the inside but directly impact the
aerodynamically relevant surfaces of the rotor blade threatened
by ice formation.
However, the special feature is the full integration of the Anti-icing
System with the lightning protection functionality. The combined
function of these two systems reduces costs while the segmen-
tation of the heating elements increases robustness, because the
failure of a single segment only slightly impairs the function of the
In order to keep the energy consumption of the Anti-icing System
as low as possible, the turbine control can adjust, fully variably,
the heating output to the prevailing climatic conditions.
Continued operation even under harsh conditions
Thanks to improved algorithms and models for the temperature
development of the rotor blade surface, no sensors are required
in the rotor blade anymore, this improves reliability and reduces
service cost. Instead, their task is managed by a sensor pos
itioned on the nacelle and, in addition, the relevant environmental
parameters are continuously monitored, with the data being for-
warded to the control unit of the system. As soon as the data pre-
dicts the danger of ice formation, the control unit automatically
switches on the heating elements. Consequently, this prevents
icing of the rotor blades before it even occurs or thaws any ice
that may have already formed.
After a turbine has been out of service – following events such
as a grid failure – a turbine equipped with the Advanced Anti-icing System can be restarted faster in freezing conditions. In a
case such as this, the turbine control unit detects the reduction in
output due to ice formation and activates the Anti-icing System.
The heating elements located close to the surface melt the ice
within a short time and the turbine can once again produce power
in the optimum output range.
The Advanced Anti-icing System for the Delta4000 has been
undergoing field tests since 2014 and is already available with
start of serial production. The existing proven Nordex Anti-icing
System is available for turbines of the Delta generation.
Left: The Advanced Anti-icing System reduces
icing-related output losses by up to 80 per cent; the
photo to the right shows a turbine with the system
deactivated for comparison purposes.
The new energy-optimised resistance heating
only acts on the areas of the rotor surface that
are particularly threatened by ice formation. As a
result, the energy consumption of the system, at a
maximum of 125 kilowatts for all three rotor blades,
is especially low.
It is a highly robust overall system due to seg-
mented heating elements. If necessary, individ-
ual segments can be replaced without having to
dismantle the rotor blade.
Losses in output due to ice formation can be
reduced by up to 80 per cent.
The advantages of the Nordex Group’s
Advanced Anti-icing System:
INSIDE PRODUCT MANAGEMENT