A fuel cell system power supply includes: a fuel cell stack configured to react hydrogen and oxygen in air with each other in order to generate electricity; a high-voltage converter configured to boost output power of the fuel cell stack; and a high-voltage junction unit configured to transmit the output power of the fuel cell stack to the high-voltage converter and to receive high-voltage power from the high-voltage converter. The high-voltage junction unit has a structure configured to simultaneously accommodate an output terminal of the fuel cell stack and an input terminal of the high-voltage converter. Consequently, the assembly structure of the high-voltage junction unit may be simplified, whereby productivity may be improved. In addition, maintainability may be improved, whereby it is possible to efficiently maintain a fuel cell vehicle.

A fuel cell system includes: a fuel cell; a fuel cell step-up converter having an input terminal, wherein the input terminal is connected to the fuel cell; a secondary cell; a secondary cell step-up converter having an input terminal an output terminal, wherein the input terminal is connected to the secondary cell. wherein the output terminal is connected to an output terminal of the fuel cell step-up converter; and a control device configured to control at least the fuel cell step-up converter and the secondary cell step-up converter to control the fuel cell system, wherein, the control device executes interruption control when the control device executes continuity control and an output of the fuel cell system is requested to be greater than an output of the secondary cell in the continuity control, wherein the continuity control is a control to control the secondary cell step-up converter to output an input voltage from the secondary cell without stepping up the input voltage, wherein the interruption control is a control to interrupt an electrical connection between the fuel cell system and the secondary cell.

Disclosed are a system and method for controlling a cold start of a fuel cell. The system includes a fuel cell configured to be supplied with fuel gas and oxidizing gas so as to generate electric power, a main bus terminal configured to electrically connect an output terminal of the fuel cell to a high-voltage battery, accessories, or a driving device so as to output the electric power generated by the fuel cell, a main relay provided at the main bus terminal between the output terminal of the fuel cell and the high-voltage battery, the accessories, or the driving device and configured to electrically connect or cut off the main bus terminal, a COD resistor connected to the main bus terminal at an output terminal side of the fuel cell with reference to the main relay, and a controller configured to supply the electric power generated by the fuel cell to the COD resistor in the state in which the main relay is cut off, and to control the COD resistor to consume the electric power generated by the fuel cell and supplied thereto.

Introduced is an fuel cell power net including a fuel cell configured to generate power through a reaction between a fuel gas and an oxidizing gas, a power storage device configured to be charged with power generated by the fuel cell or discharged to supply power, a main line configured to electrically connect the fuel cell and the power storage device to each other; a main relay disposed on the main line so as to break or make an electrical connection between the fuel cell and the power storage device, a bypass line which is branched from the main line, bypasses the main relay, and is connected to the power storage device, a bypass relay disposed on the bypass line so as to break or make an electrical connection of the bypass line, and a controller configured to control the main relay or the bypass relay such that the power stored in the storage device is supplied to the fuel cell while the power generation of the fuel cell is stopped.

A fuel cell system includes a fuel cell stack made by stacking a plurality of cells and configured to generate power by being supplied with fuel gas and oxidation gas, a high-voltage battery configured to supplement the power generated by the fuel cell stack while being charged with the power generated by the fuel cell stack or being discharged, a converter provided between the fuel cell stack and the high-voltage battery and configured to change an output voltage or an output current of the fuel cell stack, a power control unit configured to control the fuel cell stack to generate power when the fuel cell stack is requested to be diagnosed, the power control unit being configured to adjust the output current of the fuel cell stack to a predetermined current, and a voltage sensing unit configured to sense a voltage of the fuel cell stack or voltages of the plurality of cells included in the fuel cell stack in the state in which the output current of the fuel cell stack is the predetermined current.

A power net system of a fuel cell and a method for controlling the same are provided. The power net system includes: a fuel cell to generate electric power through a reaction of a fuel gas and an oxidation gas; batteries to be charged by the electric power generated by the fuel cell or discharged to supply electric power; main lines electrically connecting the fuel cell and the batteries; main relays provided in the main lines to open or allow electrical connections between the fuel cell and the batteries; COD lines branched from the main lines between the fuel cell and the main relays and provided with a COD device to consume input electric power; COD relays provided in the COD lines to open or allow electrical connections to the COD device through the COD lines; and a controller to control the main relays or the COD relays to supply electric power charged in the batteries to the fuel cell.

According to one aspect of the present invention, a hydrogen production apparatus includes a hydrogen production mechanism configured to produce a hydrogen gas from a raw material by using a catalyst; and an operation control circuit configured to input a parameter value as an index indicating a state of the catalyst, and configured to control an operation maximum load of the hydrogen production mechanism to be variable in correspondence with the parameter value.

A system and method for calibrating an offset of a pressure sensor for a fuel cell including one or more fuel cell modules in which power generation is individually controlled by independently supplying hydrogen or air to a fuel cell stack includes a pressure sensor to sense a pressure of the hydrogen supplied to the fuel cell stack, a monitoring unit which monitors whether offset calibration of the pressure sensor of the one or more fuel cell modules is required, a power generation control unit which individually controls the one or more fuel cell modules to continue or stop power generation, and a calibration control unit which calibrates the offset of the pressure sensor of the fuel cell module in a state where power generation is stopped based on a preset offset calibration period or the monitoring of the monitor unit as to whether calibration is required.

The present invention relates to the field of power sources associated with a conversion and control system of power sources based on fuel cells. The system comprises a control unit and at least one circuit arm with at least two fuel cell modules connected in series. Each fuel cell module has a bypass connected to the arm in parallel to the fuel cell. The system can be embodied with at least one circuit arm. When the system is embodied with two or more arms, these arms are interconnected in parallel. At that, each arm comprises the same quantity of installed fuel cell modules connected in series. The bypass is connected to the control unit in order to receive control signals. As an embodiment, each fuel cell module also comprises a DC/DC converter, which is in turn connected to the control unit in order to receive control signals.

A fuel cell system power supply includes: a fuel cell stack configured to react hydrogen and oxygen in air with each other in order to generate electricity; a high-voltage converter configured to boost output power of the fuel cell stack; and a high-voltage junction unit configured to transmit the output power of the fuel cell stack to the high-voltage converter and to receive high-voltage power from the high-voltage converter. The high-voltage junction unit has a structure configured to simultaneously accommodate an output terminal of the fuel cell stack and an input terminal of the high-voltage converter. Consequently, the assembly structure of the high-voltage junction unit may be simplified, whereby productivity may be improved. In addition, maintainability may be improved, whereby it is possible to efficiently maintain a fuel cell vehicle.