Life insurance for wind turbines - Wöhrle Market Soultions

How Wöhrle protects wind turbines

The latest UPS system from Wöhrle, consisting of the WP-LFP lithium battery and the WP-R2 modular UPS system, is a pioneering solution. The WP-LFP is characterized in particular by its scalability, high energy density and excellent safety. The WP-R2, on the other hand, impresses with its high efficiency and reliable availability. Together, these two products form the Wöhrle Power System, which will help to safeguard wind turbines worldwide in the future.

The energy transition

The inclusion of a global target to triple renewable energy by 2030 in the COP28 text is historic for wind power, among others. This boosts the wind industry's confidence in its growth and its role in achieving the target. GWEC Market Intelligence forecasts an increase of 791 GW of new capacity globally over the next five years (approx. 158 GW per year until 2028) under favorable policy conditions. Five pillars will support this success over the next five years:

China's high energy targets:
The Chinese government plans for more than 80 % of total energy consumption to come from non-fossil energy sources by 2060.¹
Europe's energy transition after the Ukraine crisis:
Europe is accelerating the expansion of renewable energies in order to ensure energy security following Russia's invasion of Ukraine.
USA - Renewable energies through IRA:
With the Inflation Reduction Act (IRA), the USA has made the largest investment in climate protection. This will help provide new clean energy, create local supply chains and jobs, among other things, in the period 2023-2032.

How modern wind turbines work

Modern wind turbines mainly work according to the principle of lift. This involves the use of aerodynamically shaped rotor blades, similar to those used in aircraft construction. When the wind hits the blades, pressure is created at the front, while suction is created at the rear. The nacelle, which carries the rotor, is optimally aligned with the wind using servomotors. The amount of energy generated depends, among other things, on the size of the area exposed to the air currents, which is why the rotor blades are as long as possible. Accordingly, the wind turbines grow ever taller. As a result, wind turbines with a hub height of up to 170 m are no longer a rarity. However, these large turbines are exposed to strong forces, especially at wind speeds of 25 to 30 m/sec. To prevent damage, the rotor blades are turned out of the wind when a certain maximum wind speed is reached. In this position, known as the "vane position", they offer the least resistance to the wind while the rotor turns slowly. This protective mechanism prevents the rotational forces from becoming too great and overloading the wind turbine.

Tracking with servomotor

The servomotors in the nacelle play a decisive role by ensuring both the alignment of the nacelle and the vane position.
control. These motors are essential for the performance and reliability of the wind turbine. When there is no wind, the turbine is operated via the
Medium-voltage connection supplied with electricity. In the event of a power failure in the grid, the wind turbine would not be able to react and would be at the mercy of the forces of nature. In the event of a power failure, the rotor blades must automatically switch to the vane position to avoid a potential situation in which the wind blows the blades sideways, which could lead to undesirably high forces. To prevent damage, the new Wöhrle Power System ensures that the servomotors can continuously align the nacelle so that it is always optimally positioned in the wind, even in the event of a power failure. This means that the wind always hits the turbine from the front. In this way, the blades offer the lowest air resistance in the vane position and the system is protected even in strong storms.

Wind turbines are exposed to extreme weather conditions, regardless of whether they are installed on land or in the water. They have to withstand heat, humidity and cold. A reliable power supply is therefore of crucial importance and must be specially tailored to the needs of wind turbines. Wöhrle Stromversorgungssysteme GmbH has long specialized in the development and manufacture of power supply solutions for demanding industrial applications. It produces power supplies for DC and AC systems to the highest standards. With the new Wöhrle Power System, consisting of the WP-LFP lithium battery and the WP-R2 UPS, Wöhrle offers an optimum emergency power supply for wind turbines.

Higher benefits require extended risk cover

With the steady increase in the output and size of wind turbines, particularly onshore turbines, the associated risks are also increasing. Operators must expect that there may be two to three situations in a ten-year period that lead to a loss of the medium-voltage supply. The new system from Wöhrle is specially designed for such cases. It can supply servomotors and other loads for hours on end and can therefore also bridge longer outages. It also has a considerable power reserve. The power storage unit is fully recharged after around two hours, which has a positive effect on the availability of the emergency power supply.

The uninterruptible power supply system is placed at the base of the mast. The special feature of the compact WP-LFP battery is its use of LFP cells as energy storage. This feature results in extremely short charging cycles and makes lithium technology the safest choice overall. Lithium batteries are also characterized by their exceptional resistance to temperature fluctuations. In contrast to lead-acid batteries used in the past, which reach their
While lithium batteries reach their nominal capacity and quickly lose capacity, lithium batteries are much more robust. The smaller dimensions of lithium batteries offer a considerable advantage, especially in the limited space available at the base of the wind turbine.

Although the Wöhrle UPS system, consisting of WP-LFP lithium batteries and WP-R2 UPS, is lifted into the base from above using a crane in new builds, it can also be retrofitted using a standard 19-inch cabinet.
the door in the base of the plinth.

Designed for bad weather

In addition, Wöhrle has designed the entire system for demanding environmental conditions. It can be used in a temperature range of -40 to +60 °C and at humidities of up to 95 % and an altitude of 4000 m. The system supplies 3 x 400 V as standard, whereby the outer conductors can be adapted as required. The WP-R2 offers a variety of interfaces for control and monitoring. In addition to the basic two-wire control system with relays, the emergency power supply also has a network interface. A built-in web server provides numerous operating data via an informative GUI and can also manage other systems.

Sources:

Figure 1: Forecast for global new installations of generation capacity from wind power
Lee, Joyce and Zhao, Feng. "GWEC | Global Wind Report 2024." GWEC, 2024, P. 151.

¹ Lee, Joyce and Zhao, Feng. "GWEC | Global Wind Report 2024." GWEC, 2024, P. 15.