Abstract: A method includes outputting an alternating current (AC) waveform from an inverter module to a plurality of loads, outputting a fault waveform from the inverter module to a first load of the plurality of loads in response to a fault condition associated with the first load, and outputting the AC waveform from the inverter module to at least some of the plurality of loads if the fault condition is cleared before a recovery period expires or disconnecting the inverter module from the plurality of loads if the fault condition is not cleared before the recovery period expires.

Abstract: A system for fuel cell based microgrid is provided. The system includes a plurality of fuel cell modules to generate DC power. The system includes a plurality of dual-mode inverters (DMIs) to convert the DC power into AC power. The system includes a plurality of DC switches to electrically connect or disconnect a fuel cell module from a DC bus. The DC bus is electrically coupled to the plurality of the DC switches. The plurality of DMIs includes a first set of DMIs, second set of DMIs, and a third set of DMIs. The first set is configured to electrically connect a first set of fuel cell modules with a grid. The second set of DMIs is configured to electrically connect a second set of fuel cell modules with a first load. The third set of DMIs is configured to electrically connect the DC bus with the first load.

Abstract: Excess DC current generated by a fuel cell stack may be provided to a current source inverter, and an AC current may be output by the current source inverter to a grid side bus. The AC current on the grid side bus may be used to support a load demand on a microgrid side bus or provided to a power grid. Various transmission buses and electric conditioning and control devices, such as rectifiers, current source inverters, motors, generators, electric contactors, relays, and/or transfer switches may be configured to use the AC current on the grid side bus to provide an AC current to the microgrid side bus to support the load demand on a microgrid side bus.

Abstract: A power generation method includes providing power from a first DC power source to a load, while a second DC power source is electrically disconnected from the load, electrically connecting the second DC power source to the load and providing power from the second DC power source to the load if an output voltage from the first DC power source drops below a threshold voltage and an output voltage from the second DC power source is not below the threshold voltage, and electrically disconnecting the first DC power source from the load if an output current of the first DC power source is below a threshold current.

Abstract: Excess DC current generated by a fuel cell stack may be provided to a current source inverter, and an AC current may be output by the current source inverter to a grid side bus. The AC current on the grid side bus may be used to support a load demand on a microgrid side bus or provided to a power grid. Various transmission buses and electric conditioning and control devices, such as rectifiers, current source inverters, motors, generators, electric contactors, relays, and/or transfer switches may be configured to use the AC current on the grid side bus to provide an AC current to the microgrid side bus to support the load demand on a microgrid side bus.

Abstract: A microgrid system includes first and second DC power sources electrically connected to respective first and second DC electrical power busses, a first uninterruptable power module electrically connected to the first DC electrical power bus and configured to be connected to an alternating current (AC) load, a second uninterruptable power module electrically connected to the second DC electrical power bus and configured to be connected to the AC load, a first bi-directional AC/DC inverter having a DC end and an AC end, where the first DC electrical power bus is connected to the DC end of the first bi-directional AC/DC inverter, a second bi-directional AC/DC inverter having DC and AC ends, where the second DC electrical power bus is connected to the DC end of the second bi-directional AC/DC inverter, and an AC electrical power bus electrically connected to the first and second bi-directional AC/DC inverters at their AC ends.

Abstract: Various embodiments include methods and systems for managing electric power demand distribution across electric power generators in a microgrid. The system may include electric power generator clusters each having electric power generators, electric power output units each electrically connected to at least one of the electric power generator clusters, an energy storage unit electrically connected to an electric power output unit, and a control device. The control device may be configured to determine whether an energy availability of the energy storage unit is less than an energy availability threshold, calculate a sharing multiplication factor for an electric power generator cluster in response to determining that the energy availability of the energy storage unit is less than an energy availability threshold, and calculate a sharing electric power demand for the electric power generator cluster using the sharing multiplication factor.

Abstract: During a steady-state mode of operating a fuel cell system, a system power is generated by fuel cells and is provided via a steady-state bus to a first BOP load, to a second BOP load, and to a power grid via a transformer and via at least one of a bi-directional first inverter or a bi-directional second inverter. During startup mode operation of the fuel cell system, external power from the power grid is provided via the transformer, via one of the first or second inverters and via a startup bus to the first BOP load and the second BOP load.

Abstract: A method of operating a power generator having a first electrical output electrically connected to a utility grid and a second electrical output electrically connected to a load includes detecting if the first electrical output of the power generator is electrically disconnected from the utility grid, and electrically connecting at least a neutral line of the first electrical output to ground in response to detecting that the first output is electrically disconnected from the utility grid.

Abstract: A method of operating a power generator having a first electrical output electrically connected to a utility grid and a second electrical output electrically connected to a load includes detecting if the first electrical output of the power generator is electrically disconnected from the utility grid, and electrically connecting at least a neutral line of the first electrical output to ground in response to detecting that the first output is electrically disconnected from the utility grid.

Abstract: A power generation method includes providing power from a first DC power source to a load, while a second DC power source is electrically disconnected from the load, electrically connecting the second DC power source to the load and providing power from the second DC power source to the load if an output voltage from the first DC power source drops below a threshold voltage and an output voltage from the second DC power source is not below the threshold voltage, and electrically disconnecting the first DC power source from the load if an output current of the first DC power source is below a threshold current.

Abstract: A microgrid system includes first and second DC power sources electrically connected to respective first and second DC electrical power busses, a first uninterruptable power module electrically connected to the first DC electrical power bus and configured to be connected to an alternating current (AC) load, a second uninterruptable power module electrically connected to the second DC electrical power bus and configured to be connected to the AC load, a first bi-directional AC/DC inverter having a DC end and an AC end, where the first DC electrical power bus is connected to the DC end of the first bi-directional AC/DC inverter, a second bi-directional AC/DC inverter having DC and AC ends, where the second DC electrical power bus is connected to the DC end of the second bi-directional AC/DC inverter, and an AC electrical power bus electrically connected to the first and second bi-directional AC/DC inverters at their AC ends.

Abstract: During a steady-state mode of operating a fuel cell system, a system power is generated by fuel cells and is provided via a steady-state bus to a first BOP load, to a second BOP load, and to a power grid via a transformer and via at least one of a bi-directional first inverter or a bi-directional second inverter. During startup mode operation of the fuel cell system, external power from the power grid is provided via the transformer, via one of the first or second inverters and via a startup bus to the first BOP load and the second BOP load.

Abstract: A therapeutic flotation device and a therapeutic method of use thereof is disclosed. The device includes a plurality of buoyant float elements and a member (an elongated web strap) that couples each of the buoyant float elements such that the buoyant float elements are serially aligned along the member. A first end of the member is secured to a second end of the member. A mating mechanism, such as a buckle, secures the first end of the member to the second end of the member, or the two ends of the member may be permanently secured to each other using an adhesive or by being sewn together. Each of the buoyant float elements has a center aperture aligned along the center of a cross-section thereof. The member is preferably coupled to each of the buoyant float elements by being sequentially passed through the center apertures of each buoyant float element.

Abstract: A therapeutic flotation device and a therapeutic method of use thereof is disclosed. The device includes a plurality of buoyant float elements and a member (an elongated web strap) that couples each of the buoyant float elements such that the buoyant float elements are serially aligned along the member. A first end of the member is secured to a second end of the member. A mating mechanism, such as a buckle, secures the first end of the member to the second end of the member, or the two ends of the member may be permanently secured to each other using an adhesive or by being sewn together. Each of the buoyant float elements has a center aperture aligned along the center of a cross-section thereof. The member is preferably coupled to each of the buoyant float elements by being sequentially passed through the center apertures of each buoyant float element.

Abstract: A method of operating a power generator having a first electrical output electrically connected to a utility grid and a second electrical output electrically connected to a load includes detecting if the first electrical output of the power generator is electrically disconnected from the utility grid, and electrically connecting at least a neutral line of the first electrical output to ground in response to detecting that the first output is electrically disconnected from the utility grid.