A power source assembly is provided having a fuel cell module configured to provide a first direct current power output; a battery module configured to provide a second direct current power output; a direct current electric bus configured to provide a net direct current power output to a load; a DC/DC converter in electrical connection with the direct current electric bus, the DC/DC converter configured to receive the first direct current power output from the fuel cell module or the second direct current power output from the battery module; and a controller operably coupled to the DC/DC converter and configured to receive data indicative of the first direct current power output, the controller configured to control the DC/DC converter based on the data indicative of the first direct current power output to maintain a slew rate from the fuel cell module within a slew rate range.

The disclosed embodiments relate to the design of a fuel cell system which is capable of both providing power to and receiving power from a rechargeable battery in a portable computing device. This eliminates the need for a bulky and heavy battery within the fuel cell system, which can significantly reduce the size, weight and cost of the fuel cell system. This fuel cell system includes a fuel cell stack which converts fuel into electrical power. It also includes a controller which controls operation of the fuel cell system. The fuel cell system additionally includes a power link that transfers electrical power between the fuel cell system and the portable computing device, and a communication link that provides communication between the portable computing device and the controller for the fuel cell system. The controller can regulate both the electrical power provided by the fuel cell system to the portable computing device and the electrical power provided by the rechargeable battery to the fuel cell system.

An apparatus for converting power of a fuel cell for power generation to remove an open voltage of the fuel cell when a failure occurs during power generation of the fuel cell and a method thereof are provided. A power converter converts and supplies power generated by the fuel cell to a system or load. A controller detects a failure occurring in the fuel cell, the power converter, or the system or load, while the fuel cell is driven, and reduces an open circuit voltage (OCV) of the fuel cell by a dummy resistor connected with an output terminal of the fuel cell, when the failure occurs in the fuel cell, the power converter, or the system or load. The apparatus removes an OCV of a fuel cell stack to prevent performance and life of the fuel cell from being reduced.

A system includes a plurality of power modules connected in parallel and a variable current load controller coupled to the plurality of power modules. The input terminals of the plurality of power modules are configured to be coupled to an output of a fuel cell stack, and the output terminals of the plurality of power modules are configured to supply power to a forklift. The plurality of power modules is further configured to provide electrical isolation between the fuel cell stack and the forklift. The variable current load controller is configured to regulate power distribution among the plurality of power modules.

Disclosed are a device and a method for controlling a fuel cell system, in which during operation of the fuel cell system, the device and method determine a minimum motoring current limit value applied to a motor for driving a fuel cell vehicle by varying an output current limit threshold value of the fuel cell stack by determining an available output current of the stack and by varying an available voltage lower limit threshold value of the stack by determining an available operating voltage of the stack, thereby preventing the fuel cell vehicle from rattling due to excessive limitation of output current of the stack. They also control the pressures of an anode and a cathode of the stack by monitoring whether the performance of the stack is degraded as limitation of output current of the stack is suppressed, thereby suppressing degradation of the performance of the stack.

The invention relates to a method of operating and/or fueling a compressed gas supply system (34) having at least two compressed gas tanks (15, 16, 17, 18, 19) connected to an anode path (2) of a fuel cell system (1).

To increase thermal safety during operation and/or fueling of the compressed gas supply system (34), the valve devices (21, 22, 23, 24, 25) assigned to the pressure tanks (15, 16, 17, 18, 19), which comprise a filling path with an actively switchable filling valve and a discharge path with an actively switchable discharge valve for each of the compressed gas tanks (15, 16, 17, 18, 19) are individually actuated via an electronic control unit, which is connected to a sensor device having at least one sensor, which senses a current temperature in the respective valve installation (21, 22, 23, 24, 25).

A method for operating a fuel cell power plant is provided to deliver power and/or receive power from a load. The fuel cell power plant includes an energy storage system connected in parallel with a fuel cell system. The method for operating includes the steps of calculating and actively proportioning a current split between the fuel cell system and the energy storage system, and controlling the proportioning using fuel cell system air flow. In one embodiment, set point changes in the fuel cell system air flow are operationally independent from a fuel cell water management system that removes product water, humidifies inlet reactant gas, and/or cools the fuel cell stack. In another embodiment, the step of calculating the current split proportion includes the selection of points on a family of V/I curves within a range from 40% fuel cell air utilization to 99% fuel cell air utilization.

The invention relates to a fuel cell system (100), wherein the fuel cell system (100) comprises a fuel cell stack (10) for generating an output voltage and a boost converter (30) for increasing the output voltage of the fuel cell stack (10), having at least one converter unit (31a, 31b, 31c, 31d), wherein the converter unit (31a, 31b, 31c, 31d) comprises a coil (33) and a controllable switch (34) for increasing the output voltage of the fuel cell stack (10), wherein the controllable switch (34) comprises a variable resistor. Furthermore, the fuel cell system (100) comprises a control apparatus (50), wherein the control apparatus is configured so as to control the controllable switch (34) of the at least one converter unit (31a, 31b, 31c, 31d) in such a way that the resistor of the controllable switch (34) of the at least one converter unit (31a, 31b, 31c, 31d) is adjusted for controlling a heating current for temperature control of the fuel cell stack (10).