LHUVkraft is a project funded by the Federal Ministry for Economic Affairs and Climate Action aimed at increasing the power density of converters for wind turbines.

The trend towards higher power levels in wind turbines is unbroken. This is the only way to achieve expansion targets and the required reduction in the cost of electricity generation from renewable energy sources, particularly onshore where available locations are limited. As tower height and power increase, current turbine designs incorporate the transformer and the entire power electronics into the nacelle. This can reduce cable losses by several percent of the plant's power output. However, with increasing power levels, the requirements for the power density of converters become stricter.

This is where LHUVkraft comes in. Using innovative silicon carbide (SiC) power transistors, the switching frequency of the converter will be significantly increased. This allows for a substantial reduction in the mass and volume of current-carrying components such as grid inductors – the dominant component in the converter in terms of space – and motor chokes, busbars, and switching devices. The project plans to research, implement, and validate innovations from the semiconductor level to converter testing in a wind turbine.

In the sub-project at the University of Rostock, the following key areas are addressed:

• Innovative drive concepts for SiC-MOSFETs to avoid negative gate-source voltages, improve short-circuit resistance, and reduce switching losses.
• Converter technology for high-power SiC-MOSFET modules, particularly oscillation damping and parallel connection.
• Hybrid switches as a cost-optimized compromise between conventional and full-SiC solutions.
• Design calculations using generic Type 3 and Type 4 wind turbines to determine the performance and efficiency of SiC wind converters.