Common DC bus based multi-frequency converter system for vessel

The invention discloses a heterodyne-converter system based on public DC bus technology for boat and is characterized in that: a plurality of frequency changers are connected with respective public DC bus and is connected with the main three phase power source inside the boat through a public ratifying device. The public rectifying device finishes the transforming from the main three phase power source to public DC power source and provides DC power for each frequency changer through the public DC bus, each frequency changer drives respective non-synchronous motor. The heterodyne-converter system for boat needs only a group of public input wave filter device, a group of public three phase rectifying device, a group of public overpressure chopped wave unit and a group of public insulating inspection device to supply reliable work insurance for the posterior pole system made of heterodyneconverter system. The invention greatly increases the work reliability of the whole system and is mainly applied in the DC drive frequency changing system of boat for heterodyne-converter drive of the windlass load, blower load and pump load.