Mitsui Develops Overhang Permanent Magnet Shaft Generator

Mitsui E&S and Taiyo Electric have developed an Overhang Permanent Magnet Shaft Generating System for large marine engines.

Unlike Taiyo Electric’s conventional shaft generators installed on intermediate shafts, this new system is mounted on the fore end of the main engine. This configuration minimizes the impact on engine room layout and stern hull design, contributing to improved fuel efficiency and enhanced energy-saving performance for vessels.

In addition, the engine and generator can be ordered and delivered as further a single package, helping reduce the workload of shipyards during installation and outfitting.

The system adopts a permanent magnet generator, which offers higher efficiency and a more compact and lightweight design compared to conventional wound-rotor types. The reduced number of periodically replaced components also contributes to improved maintainability.

In addition to PTO (power generation), the system supports engine-assist operation through PTI (driving the generator as a motor) by providing supplemental propulsion power when required. This supports stable vessel operation even under adverse weather conditions or in situations where additional acceleration is needed.