A vessel power supply system for a vessel including a propulsion device that includes an engine and a generator driven by the engine to generate electricity, includes a first battery that supplies power to the propulsion device, a second battery that supplies power to accessories of the vessel, a first open circuit voltage sensor that detects an open circuit voltage of the first battery, a second open circuit voltage sensor that detects an open circuit voltage of the second battery, and a switch that is turned on/off to open and close a current path between the first battery and the second battery.

A buoyant vessel having a hull and a drive system mounted to the hull, the system having a rectifier, a generator, an AC bus in communication with shore power or a charging system and the rectifier, a DC bus in communication with the rectifier, at least one energy storage system, an inverter, a prime mover, a load regenerating device, and a control and monitor system which has predefined specifications for at least one of: storage units of at least one energy storage system; stored therein and wherein the control and monitor system is adapted to: automatically control the DC/DC converters, relieve a current draw from one or more storage units, provide charging current, and automatically draw power and redirect energy.

A buoyant vessel having a hull and a drive system mounted to the hull, the system having a rectifier, a generator, an AC bus in communication with shore power or a charging system and the rectifier, a DC bus in communication with the rectifier, at least one energy storage system, an inverter, a prime mover, a load regenerating device, and a control and monitor system which has predefined specifications for at least one of: storage units of at least one energy storage system; stored therein and wherein the control and monitor system is adapted to: automatically control the DC/DC converters, relieve a current draw from one or more storage units, provide charging current, and automatically draw power and redirect energy.

A rotor for a permanent magnet machine includes first and second axially successive rotor sections each including permanent magnets generating magnetic field having a pole pitch. The rotor includes a first coupling system for connecting the first rotor section to a shaft and a second coupling system for connecting the second rotor section to the shaft or to the first rotor section. The second rotor section is rotatable with respect to the first rotor section by an angle corresponding to the pole pitch in response to releasing the second coupling system so as to set the stator flux-linkages generated by the first and second rotor sections to be substantially zeroes. Thereafter, the permanent magnets do not substantially induce voltages on the stator windings even if the rotor is rotating during for example an internal fault of stator windings.

A rotor for a permanent magnet machine includes first and second axially successive rotor sections each including permanent magnets generating magnetic field having a pole pitch. The rotor includes a first coupling system for connecting the first rotor section to a shaft and a second coupling system for connecting the second rotor section to the shaft or to the first rotor section. The second rotor section is rotatable with respect to the first rotor section by an angle corresponding to the pole pitch in response to releasing the second coupling system so as to set the stator flux-linkages generated by the first and second rotor sections to be substantially zeroes. Thereafter, the permanent magnets do not substantially induce voltages on the stator windings even if the rotor is rotating during for example an internal fault of stator windings.

A hybrid electrical and mechanical ship propulsion and electric power system, includes a first mechanical power plant configured to drive a first propeller via a first shaft. There is a second electrical power plant configured to drive a second propeller via a second shaft. The second electrical power plant includes HTS generators and a high temperature superconductor (HTS) motor interconnected to the second shaft. There is a first electrical network to which the HTS motor is connected in order to energize the HTS motor to drive the second propeller via the second shaft.

A hybrid electrical and mechanical ship propulsion and electric power system, includes a first mechanical power plant configured to drive a first propeller via a first shaft. There is a second electrical power plant configured to drive a second propeller via a second shaft. The second electrical power plant includes HTS generators and a high temperature superconductor (HTS) motor interconnected to the second shaft. There is a first electrical network to which the HTS motor is connected in order to energize the HTS motor to drive the second propeller via the second shaft.

A vessel power supply system for a vessel including a propulsion device that includes an engine and a generator driven by the engine to generate electricity, includes a first battery that supplies power to the propulsion device, a second battery that supplies power to accessories of the vessel, a first open circuit voltage sensor that detects an open circuit voltage of the first battery, a second open circuit voltage sensor that detects an open circuit voltage of the second battery, and a switch that is turned on/off to open and close a current path between the first battery and the second battery.

A vessel power supply system for a vessel including a propulsion device that includes an engine and a generator driven by the engine to generate electricity, includes a first battery that supplies power to the propulsion device, a second battery that supplies power to accessories of the vessel, a first open circuit voltage sensor that detects an open circuit voltage of the first battery, a second open circuit voltage sensor that detects an open circuit voltage of the second battery, and a switch that is turned on/off to open and close a current path between the first battery and the second battery.

This disclosure provides improved nautical craft that can travel and navigate on their own. A hybrid vessel is described that converts wave motion to locomotive thrust by mechanical means, and also converts wave motion to electrical power for storage in a battery. The electrical power can then be tapped to provide locomotive power during periods where wave motion is inadequate and during deployment. The electrical power can also be tapped to even out the undulating thrust that is created when locomotion of the vessel is powered by wave motion alone.