Products
Wind energy Converters
On developing our first turbine, we rely on combining proven concepts and components
with a sense of innovation. This guarantees a balanced relationship between innovation,
reliability and safety.
‘BARD 5.0’ is a 5 MW WEC (wind energy converter) dedicated for use in rough offshore conditions
and designed in co-operation with aerodyn Energiesysteme GmbH in Rendsburg. Right from the
beginning our concept has convinced all involved financing and insurance companies. The best
way to meet our high quality requirements is to build our own WEC. This will also ensure that
from 2009 and forward we will have as many turbines available as required for our projects.
The BARD offshore nacelle weighs approx. 280 t which is about average for today’s 5 MW WECs. The rotor shaft turns in a double-row tapered roller bearing, which is mounted, together with the transmission, on a bedplate of vibration-isolating nodular cast iron. The drive train comprising rotor shaft, transmission, drive shaft, generator and converter for the first two turbines have been developed by Winergy AG in Voerde/ Friedrichsfeld in Niederrhein.Winergy is worldwide market leader in wind turbine transmissions. Winergy condition monitoring system has been tested and certified by Allianz Centre for Technology (AZT), a reputable institution for technical surveillance.
By the year 2010 we will be operating a maximum of 80 WECs in the ‘BARD Offshore 1’ wind
farm. The power is transmitted to an energy platform. There will be a transformer installed on the
energy platform to transform the power from 33kV into 150kV. On an extra rectifier platform the
AC will be transferred into DC, after this the electrical energy is transported to the mainland via
a high-voltage cable. The platform complex will also include a habitation platform for operating
staff.
| ‘BARD 5.0’ – Technical data | |
|---|---|
| Rotor diameter | 122 m |
| Starting wind speed Vin | 3 m/ s |
| Nominal power Vr of ‘BARD 61’ | 12.5 m/ s |
| Cut out wind speed Vout (600 s mean value) | 25 m/ s |
| Cut out wind speed VA (1 s mean value) | 30 m/ s |
| Service life | 20 years |
| Type category | TC 1C |
| (GL Guidelines, 2005) | |
At the connecting point in Diele, where DC is converted back to required 50 Hz AC, we feed into the public grid of E.ON Netz GmbH. To prove that we can meet the stated technical requirements for grid connection we have already ordered studies performed and finalized by both Siemens and ABB.
The foundations and wind turbines are transported to the project site by means of tugs and pontoons. The installation is preformed by our own jack-up heavy lift vessel which is equipped with a dedicated heavy-lift crane. The platform is equipped with 4 legs, each more than 80 m long which are lowered down to the sea bed and jack-up the vessel out of the water. This ensures a stable installation platform at water depths up to 45 m, which guarantees that the crane drivers and the installation crew can install wind turbines unimpeded by the waves. Taking the size of the wind farm and the corresponding investment into account, it is economically viable to maintain a jack-up vessel dedicated to our needs. Not willing to make compromises or to rely on the availability of similar vessels on the market and demanding a high availability throughout the year this vessel is designed for our needs.
This philosophy will also apply to the operation of all our wind energy converters. As a base for continuous operation and maintenance a habitation platform will be installed in our wind farm. The platform will be manned 365 days a year with a service staff equipped with the necessary spare-parts for an immediate repair of minor errors or the exchange of defective components. To provide access to every offshore wind energy converter a conventional operating vessel will be stationed in the wind farm to transfer the service crew from the platform to wind turbines.
| ‘BARD 5.0’ – Rotor | |
|---|---|
| Axis inclination | 5° |
| Cone angle | – 3.5° |
| Rotor arrangement | windward side |
| Blade mass (incl. blade connection) | approx. 28,5 t |
| Pitch circle diameter (blade connection) | 4 m |
| Hub mass (incl. pitch position and equipment) | approx. 70 t |
| Nacelle (incl. generator, without blades and hub) | approx. 280 t |
Delivery of the hub to the pier „At the Knock” at the Rysumer Nacken
| ‘BARD 5.0’ – Tower | |
|---|---|
| Type | Steel pipe tower |
| Hub height onshore prototype | 90 m |
| Hub height offshore | 90 m |
| Tower top diameter | 4.5 m |
| Tower bottom diameter | 5.5 m |
Delivery of the lowest tower segment of BARD 5.0’s 90m high tower to the pier „At the Knock” at the Rysumer Nacken
Designed for Efficiency
‘BARD 5.0’ with 5 MW nominal output incorporates worldwide experience in offshore in offshore wind power plant development and operation.
A three-blade rotor with a diameter of 122 m is attached conventionally upwind to the nacelle. On account of the diameter, ‘BARD 5.0’ achieves its nominal output at low wind speeds, and can still produce power in high wind speeds. Regenerative electrical power which will become even more competitive in the foreseeable future due to the rising prices for conventionally generated power.
‘BARD 5.0’ WECs will start generating power at a wind speed of 3 m/s. which is equal to 2 Beaufort, a light breeze. Wind measurements at ‘FINO I‘ research platform, north of the isle of Borkum, have shown that the wind at high seas exceeds the above mentioned wind speed more than 90 % of the year. It means that more than 8,000 hours of regenerative power can be fed into the public grid.
Five azimuth drives between the tower and the nacelle ensure optimal positioning of the rotor to the wind. Output is regulated by the pitch angle at which the rotor blades will be positioned towards the wind. Each blade is positioned by its own electrical pitch motor which is controlled by a battery-backed frequency converter. It ensures that we can pitch all blades into stop position, even in case of a complete grid failure.
If the wind speed exceeds 3 m/s, the controller will start the wind turbine automatically, the pitch motors will turn the ‘BARD 61’ rotor blades into the start position. At a wind speed of 12 m/s, ‘BARD 5.0’ reaches its nominal output, above this wind speed the turbine will stabilize its output at 5 MW. To ensure that the generator runs with the designed constant torque, the controller will continuously adjusts the blade angle to the current wind speed.
| ‘BARD 5.0’ – Generator | |
|---|---|
| Nominal capacity (elect. outlet) | 5,276.2 kW |
| Nominal torque (inlet) | 42.9 kNm |
| Nominal speed | 1.212 rev/min. |
| Efficiency at nominal capacity | 0.968 |
| Type | Twin-fed asynchronous engine |
The nacelle of the BARD 5.0 prototype being transported via pontoon from the manufacturing hall at the Jarsumer port to the test field at the Rysumer Nacken near the Dollart
| ‘BARD 5.0’ – Transmission | |
|---|---|
| Type | 2 planetary levels, 1 cylindrical gear level |
| Transmission ratio | 96.965 |
| Nominal capacity (inlet) | 5,630 kW |
| Nominal torque (inlet) | 4,301.3 kNm |
| Efficiency at nominal capacity | 0.970 |
When the wind has reached a speed of 30 m/s, which is equivalent to a storm of 11 Beaufort, the rotor blades will turn into the ‘vane position’, providing lowest resistance and minimum surface area to the wind.
To take up the enormous forces, we have selected a double-row tapered roller bearing as the main bearing of the rotor shaft. The gearbox is provided by Winergy AG and is equipped with two planetary stages and one helical stage. The generator is a double-fed asynchronous generator, which is a well-proven concept for multi-megawatt turbines in the range from two to five megawatts. The frequency converter has been designed in a modular redundant setup. In case one module fails, the overall system is not endangered. This redundant setup guarantees a high availability and efficient maintenance.
During operation we monitor all different features of the controlling system. The complete data on the generated power, pitch system, oil pressure, wear, temperatures and vibrations is stored in a high resolution. This data is used to control the operation of the turbine as well as to optimize the system. Important data will be monitored by use of redundant devices. In case of a failure, the controller will disconnect the generator from the grid and bring the turbine in a safe mode to avoid unnecessary damage to ‘BARD 5.0’.