Shaft generators manufactured by AEM in PTO/PTI-mode
Shaft generators unlike typical generators for the main power supply are not
coupled to their own diesel motor. They are instead driven via power train
of the main diesel or the propeller shaft respectively.
During regular PTO-mode (Power Take Out), the shaft generator supplies the
main supply with power. In PTI-mode (Power Take In), the generator operates
as synchronous motor, supplied by the generators of the auxiliary diesel
units. The PTI-mode can be split in PTH-mode (Power Take Home) and Booster
mode. In case the main drive fails, PTH-mode ensures manoeuvrability of the
vessel and makes it possible to reach the next port. During this mode, the
synchronous machine is started by the pony motor (asynchronous motor) it is
mounted to. Following that, it powers the propeller of the vessel as
synchronous motor with decreased speed in emergency operation. In Booster
mode, the propeller is supplied with additional power via gear box (f. ex.
in case of ice drift or other challenging conditions).
AEM delivers all shaft generators for marine applications certified
according to the rules of the major classification societies.
