Development of inverter-less FPP electric propulsion system

Electric propulsion is thought to be a more effective propulsion system and with government support the number of ships applying this type of system has increased in past years. However the conventional system requires inverter to change propeller revolution, thus making it very complex and expensive. This is because the system is constructed with basic concept that generator engine should be operated with constant revolution. The authors found that the output frequency and generator voltage are proportional to the generator engine revolution, which is the same phenomena as that of the inverter. With this idea, the authors constructed the “Inverter-less FPP electric propulsion system” and confirmed the effects with simple experiments. Furthermore the system was applied to the model ship “Shioji-Maru”(training ship of TUMSAT). Static performance was confirmed with water tank test.