Presenting the Winergy HybridDrive: the promising mid-speed drive train for offshore wind turbines 

Over the last years, climate change has become an increasingly central concern for environment and society. The geopolitical situation as well as the Paris Agreement and COP26 are forcing the renewable energy transition and presenting the wind industry with new challenges. In order to meet the future energy demand of the world, capacities must be massively expanded. Offshore wind is particularly promising in this respect, as there is still great performance potential to be tapped. 
It used to be common practice in the wind industry for the turbine OEM to break down a planned drive system into individual main components and specify each component separately. However, this has been changed, particularly due to the huge pressure to reduce LCoE (Levelized Cost of Energy) in many major markets. Leading OEMs such as Vestas¹ and Goldwind² are already focusing on developing mid-speed drivetrains and the associated system-level cost savings.
The demand of mid-speed drive train components is increasing and Winergy is a reliable supplier to meet these requirements. Back in 2012, the visionary idea of the HybridDrive was born, directly connecting the gearbox and generator, thus realizing the most compact and lightweight drivetrain. Since then, Winergy have gained test and field experience with systems between 3 to 6 MW and have continuously refined our design guidelines and competences as part of development projects. Instead of being connected by a coupling, the gearbox and generator now share only one common bearing and housing, without need for any safety clutch.

Increasing system reliability with the HybridDrive

Increased operational reliability and short downtimes are particularly important for offshore applications, as the turbines are difficult to reach and service measures are therefore very costly. The system concept of the HybridDrive will support and optimize this as follows. 
The modular design of the HybridDrive enables a drivetrain development with reduced technical risk. By Winergy, mechanical and electrical components have been developed optimally and manufactured reliably for over 40 years. The functional integration of gearbox and generator allows a compact and lightweight design with only one common bearing for the generator and the sun shaft of the intermediate stage (IMS) and without need of a Non-Drive-End (NDE) bearing for the generator. Depending on the required level of braking torque, the brake disc can be integrated internally to the drive end side (DE) of the generator.
Due to the mid-speed drive technology, the noise level decreases significantly along with the reduced output speed of the gearbox. In addition, the HybridDrive may feature an oil-water-cooled generator without an additional fan usually used for air-water-cooled or direct air-cooled generators. Next to the high-power density, the outstanding encapsulation of the stator winding increases system safety. Immediately after assembly, end-of-line system tests are carried out at Winergy factory to ensure the highest reliability on all components of the drive train. 
The Winergy HybridDrive is characterized by high reliability, compact design and high-cost efficiency at system level in increasing power classes. As supplier for the HybridDrive system, Winergy offers its customers mechanical and electrical competence to support the growth in renewable energies in onshore and especially offshore wind application.
On May 5, 2022, the first Winergy webcast took place, providing further information on the impact of the wind market on future offshore drivetrain concepts. In our web archive you can gain insights about different wind turbine drivetrain concepts with their advantages and challenges. Webcasts | Flender

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