Wärtsilä LLC Quattro

The LLC – Quattro is an electric distribution system shaped as a ring-network. Included in the network are four phase-shift transformers that constantly maintain a 30 degrees phase shift between the single bus bars.
This configuration provides maximum propeller availability through multiple supplies to the propeller drives. The reduced electric losses result in notably improved fuel consumption. 

The ring shaped network of the LLC – Quattro, and its inherent lower short-circuit current level, enables the utilization of medium voltage (MV) converters with system voltages up to 6660V. This concept is suitable for applications up to approximately 70MW of installed power.
The Low voltage version will be able to operate in a ring configuration for up to 18MW of installed power generation.

The transformerless setup results in significant weight and space savings for the electric equipment. This also affects the supporting equipment, such as the cooling systems, foundations and cable installations.
The electric losses for the Quattro LLC are generally 2-3% lower than with an equivalent transformer-based solution.