Provided is a renewable energy power generation system (10) having a renewable energy power generating apparatus (12) arranged to generate electric power; and a hydrogen power generation module (20) having a separation unit (22) adapted to separate water into hydrogen and oxygen, and a fuel cell unit (28) adapted to receive air or oxygen, and hydrogen from said separation unit or from a hydrogen storage; the fuel cell unit being arranged to produce electric power in the presence of hydrogen and oxygen; wherein the hydrogen power generation module being adapted to receive electric power from the at least one renewable energy power generating apparatus at least prior to production of electric power by the fuel cell unit.

An electrical power generating system for providing auxiliary or backup power to a load bus. The system may be used indoors, and generally includes a fuel cell unit comprising a first DC output, an electrical storage unit comprising a DC input coupled to the first DC output of the fuel cell, the electrical storage unit further comprising a second DC output. An inverter coupled to the second DC output receives power, the inverter comprising a first AC output. The system includes a contactor connected between the first AC output and an AC load bus. The AC load bus comprises an AC voltage, and a controller comprising inputs is adapted to sense a phase, a frequency, and a magnitude of the first AC output and the AC voltage and close the contactor when they substantially match.

An apparatus (10) configured to determine reactant purity comprising: a first fuel cell (11) configured to generate electrical current from the electrochemical reaction between two reactants, having a first reactant inlet (13) configured to receive a test reactant comprising one of the two reactants from a first reactant source (7, 5, 16); a second fuel cell (12) configured to generate electrical current from the electrochemical reaction between the two reactants, having a second reactant inlet (14) configured to receive the test reactant from a second reactant source (5); a controller (20) configured to apply an electrical load to each fuel cell and determine an electrical output difference, OD.sub.t, between an electrical output of the first fuel cell (11) and an electrical output of the second fuel cell (12), and determine a difference between a predicted output difference and the determined electrical output difference, OD.sub.t, the predicted output difference determined based on a historical output of difference and a historical rate of change in said output difference determined at an earlier time, said controller (20) configured to provide a purity output indicative of the test reactant purity at least based on the difference between the predicted and determined output difference.

Disclosed are a grid-connected power conversion system and a control method thereof. The grid-connected power conversion system includes a fuel cell stack generating a DC voltage, a power conversion system (PCS) converting the DC voltage supplied from the stack into an AC voltage, a multi-input transformer including a primary coil having a plurality of voltage input terminals and a secondary coil transforming a magnitude of the voltage applied to the primary coil and outputting the transformed voltage, the plurality of voltage input terminals determining the number of turns of the primary coil differently from each other, one of the plurality of voltage input terminals receiving the AC voltage converted in the PCS, and a controller selecting the one of the plurality of voltage input terminals of the multi-input transformer based on the magnitude of the DC voltage generated from the stack and determining whether to replace the stack.

An electrical power generating system for providing auxiliary or backup power to a load bus. The system may be used indoors, and generally includes a fuel cell unit comprising a first DC output, an electrical storage unit comprising a DC input coupled to the first DC output of the fuel cell, the electrical storage unit further comprising a second DC output. An inverter coupled to the second DC output receives power, the inverter comprising a first AC output. The system includes a contactor connected between the first AC output and an AC load bus. The AC load bus comprises an AC voltage, and a controller comprising inputs is adapted to sense a phase, a frequency, and a magnitude of the first AC output and the AC voltage and close the contactor when they substantially match.

An energy management system having a fuel cell apparatus (150) as a power generator that generates power using fuel, and an EMS (200) that communicates with the fuel cell apparatus (150). The EMS (200) receives messages that indicate the status of the fuel cell apparatus (150) when normal operation, from the fuel cell apparatus (150).

An uninterruptible power supply (UPS) system or other power system includes a primary power source and a fuel cell and battery system as a backup power source. The fuel cell and battery backup system(s) are integrated into the primary power source to reduce the required power components and to provide high-quality power conditioning for the UPS system. A control system receives and analyzes data from the primary power source, as well as from the fuel cell and battery backup systems, to perform advanced power management and sharing, manage transitions, export power to the grid, and manage boil-off losses at the fuel cell.

A power distribution system includes at least two DC buses and at least two AC buses and a plurality of converter units interconnecting the DC buses and the AC buses in a ring. The system may further include one or more AC power sources (e.g., utility feeds, engine-generator sets, etc.) connected to selected ones of the AC buses and/or one or more DC power sources (batteries, capacitor banks, fuel cells, etc.) connected to selected ones of the DC buses. The ring configuration can support a variety of AC and DC loads and provide redundancy and power distribution among the power sources.

An uninterruptible power supply (UPS) system or other power system includes a primary power source and a fuel cell and battery system as a backup power source. The fuel cell and battery backup system(s) are integrated into the primary power source to reduce the required power components and to provide high-quality power conditioning for the UPS system. A control system receives and analyzes data from the primary power source, as well as from the fuel cell and battery backup systems, to perform advanced power management and sharing, manage transitions, export power to the grid, and manage boil-off losses at the fuel cell.

A drive circuit comprising a DC bus configured to supply power to a load, a first fuel cell coupled to the DC bus and configured to provide a first power output to the DC bus, and a second fuel cell coupled to the DC bus and configured to provide a second power output to the DC bus supplemental to the first fuel cell. The drive circuit further includes an energy storage device coupled to the DC bus and configured to receive energy from the DC bus when a combined output of the first and second fuel cells is greater than a power demand from a load, and provide energy to the DC bus when the combined output of the first and second fuel cells is less than the power demand from the load.