A system and method for synchronizing a frequency of plurality of variable frequency generators with a variable frequency load over a variable frequency bus independent of a frequency conversion stage. A synchronization controller is configured to determine an optimal bus frequency of the variable frequency bus based on at least one power demand requirement of the variable frequency load operatively connected to the variable frequency bus. With the optimal frequency, an available power range supplied by the plurality of variable frequency gensets at the optimal bus frequency can be determined. The synchronization controller then asymmetrically loads the variable frequency load to the plurality variable frequency gensets at the optimal bus frequency based on the operating range of each variable frequency genset and recursively updates the optimal bus frequency based on operational statistics of the asymmetrically loaded variable frequency gensets.

A system and method for synchronizing a frequency of plurality of variable frequency generators with a variable frequency load over a variable frequency bus independent of a frequency conversion stage. A synchronization controller is configured to determine an optimal bus frequency of the variable frequency bus based on at least one power demand requirement of the variable frequency load operatively connected to the variable frequency bus. With the optimal frequency, an available power range supplied by the plurality of variable frequency gensets at the optimal bus frequency can be determined. The synchronization controller then asymmetrically loads the variable frequency load to the plurality variable frequency gensets at the optimal bus frequency based on the operating range of each variable frequency genset and recursively updates the optimal bus frequency based on operational statistics of the asymmetrically loaded variable frequency gensets.

An electromotive drive device for a floatable device includes an electric motor operable by means of a separate power supply module with an energy accumulator, an electronic open-loop/closed-loop control unit and a remote control. The electric motor is within a housing connected to a drive propeller, which at least partially is surrounded by a protective device connected to the housing via connecting supports. The housing has an upper housing part and a lower housing part connected to each other by at least one releasable connection. The housing includes an elliptical bow, the end thereof transitioning into an essentially circular diameter with relative dimensions being a sum larger than an end of the housing with a projection opposite the bow. The housing in the lateral area behind the diameter is provided with intake openings for cooling water to flow inward. The cooling water can exit via outlet openings provided in the connecting supports. An operating method for the drive device includes an electronic open-loop/closed-loop control unit with an information processing unit. The drive ensures energetic use of the power supply module by reducing power while considering a travelled distance or travel time of the floatable device.

An electromotive drive device for a floatable device includes an electric motor operable by means of a separate power supply module with an energy accumulator, an electronic open-loop/closed-loop control unit and a remote control. The electric motor is within a housing connected to a drive propeller, which at least partially is surrounded by a protective device connected to the housing via connecting supports. The housing has an upper housing part and a lower housing part connected to each other by at least one releasable connection. The housing includes an elliptical bow, the end thereof transitioning into an essentially circular diameter with relative dimensions being a sum larger than an end of the housing with a projection opposite the bow. The housing in the lateral area behind the diameter is provided with intake openings for cooling water to flow inward. The cooling water can exit via outlet openings provided in the connecting supports. An operating method for the drive device includes an electronic open-loop/closed-loop control unit with an information processing unit. The drive ensures energetic use of the power supply module by reducing power while considering a travelled distance or travel time of the floatable device.

A system and method for synchronizing a frequency of plurality of variable frequency generators with a variable frequency load over a variable frequency bus independent of a frequency conversion stage. A synchronization controller is configured to determine an optimal bus frequency of the variable frequency bus based on at least one power demand requirement of the variable frequency load operatively connected to the variable frequency bus. With the optimal frequency, an available power range supplied by the plurality of variable frequency gensets at the optimal bus frequency can be determined. The synchronization controller then asymmetrically loads the variable frequency load to the plurality variable frequency gensets at the optimal bus frequency based on the operating range of each variable frequency genset and recursively updates the optimal bus frequency based on operational statistics of the asymmetrically loaded variable frequency gensets.

A system and method for synchronizing a frequency of plurality of variable frequency generators with a variable frequency load over a variable frequency bus independent of a frequency conversion stage. A synchronization controller is configured to determine an optimal bus frequency of the variable frequency bus based on at least one power demand requirement of the variable frequency load operatively connected to the variable frequency bus. With the optimal frequency, an available power range supplied by the plurality of variable frequency gensets at the optimal bus frequency can be determined. The synchronization controller then asymmetrically loads the variable frequency load to the plurality variable frequency gensets at the optimal bus frequency based on the operating range of each variable frequency genset and recursively updates the optimal bus frequency based on operational statistics of the asymmetrically loaded variable frequency gensets.

A motorized inflatable raft includes independently controllable propellers to propel the raft. The propellers are part of a propeller control assembly that includes a power source and a joystick for control. Direction of motion is controlled by rotating independent propeller control assemblies using a joystick controller. Power is supplied by batteries in a battery housing, and application of power to the propellers is controlled by the joystick. Assembly is simplified using an easily screwed screw cap that securely fastens a battery housing that is connected through tubing to the propeller to the joystick controller.

A motorized inflatable raft includes independently controllable propellers to propel the raft. The propellers are part of a propeller control assembly that includes a power source and a joystick for control. Direction of motion is controlled by rotating independent propeller control assemblies using a joystick controller. Power is supplied by batteries in a battery housing, and application of power to the propellers is controlled by the joystick. Assembly is simplified using an easily screwed screw cap that securely fastens a battery housing that is connected through tubing to the propeller to the joystick controller.

A pool cleaning device is provided, including: a main body; a rotating unit rotatably disposed on the main body, the rotating unit including a rotating member, a fluid outlet extending radially outward from the rotating member, and a first positioning protrusion extending radially outward from the rotating member and spaced apart from the fluid outlet; and a reversing member including a plurality of stoppers spaced apart from each other and disposed along a path of rotation of the rotating member. Each of the plurality of stoppers is reciprocable between a position in a path of rotation of the first positioning protrusion and a position out of the path of rotation of the first positioning protrusion.

A pool cleaning device is provided, including: a main body; a rotating unit rotatably disposed on the main body, the rotating unit including a rotating member, a fluid outlet extending radially outward from the rotating member, and a first positioning protrusion extending radially outward from the rotating member and spaced apart from the fluid outlet; and a reversing member including a plurality of stoppers spaced apart from each other and disposed along a path of rotation of the rotating member. Each of the plurality of stoppers is reciprocable between a position in a path of rotation of the first positioning protrusion and a position out of the path of rotation of the first positioning protrusion.