A method for starting a cold or frozen fuel cell stack as efficiently and quickly as possible in a vehicle application is based upon a state of charge of a first power source such as a high voltage battery. Power flow between the first power source and fuel cell system is coordinated in conjunction with a specific load schedule and parallel control algorithms to minimize the start time required and optimize system warm-up.

A system (0) includes an electrical load system (54) with a load network battery (82), and a fuel cell system (1). Operation is simplified, especially during start of the fuel cell system (1) if the fuel cell system (1) has a system battery (56). A system voltage across the system battery (56) can be supplied to electrical system loads (80) of the fuel cell system (1) and, via a load voltage converter (77) and at least one additional voltage converter (86), to the load system (54) and secondary electrical loads (84, 85).

A fuel-cell vehicle in which a fuel cell which is a driving power source is mounted includes a refrigerant flow passage that is connected to the fuel cell, a first pump that causes a refrigerant to flow in the refrigerant flow passage, a heater that heats the refrigerant, and a connection part that is electrically connected to the heater and the first pump and that is used for electrical connection to an external power source which is provided outside the fuel-cell vehicle. The heater and the first pump are driven with electric power supplied from the external power source which is connected thereto via the connection part.

According to an embodiment, a control system includes a fuel cell configured to generate electric power using an anode and a cathode, a power storage device capable of storing the electric power generated by the fuel cell, auxiliary equipment to which the electric power is able to be supplied, and a controller configured to control operations of the fuel cell and the auxiliary equipment. The controller performs control so that the electric power is consumed by the auxiliary equipment in accordance with a power storage state of the power storage device at the time of power generation of the fuel cell and adjusts one or both of a timing and a degree at which electric power to be consumed by the auxiliary equipment is limited on the basis of temperature information associated with the auxiliary equipment.

According to an embodiment, a control system includes a fuel cell configured to generate electric power using an anode and a cathode, a power storage device capable of storing the electric power generated by the fuel cell, auxiliary equipment to which the electric power is able to be supplied, and a controller configured to control operations of the fuel cell and the auxiliary equipment. The controller performs control so that the electric power is consumed by the auxiliary equipment in accordance with a power storage state of the power storage device at the time of power generation of the fuel cell and adjusts one or both of a timing and a degree at which electric power to be consumed by the auxiliary equipment is limited on the basis of temperature information associated with the auxiliary equipment.

An electrically driven motor vehicle may include a first cooling circuit, a first component, a first heat exchanger, at least one pump configured to convey a coolant, a second cooling circuit, and a second component. The first component may be arranged in the first cooling circuit and may have a temperature which is to be controlled. The second component may be arranged in the second cooling circuit and may have a temperature which is to be controlled. The first cooling circuit and the second cooling circuit may be fluidically separated from one another and may be coupled to one another to transfer heat via a second heat exchanger. One of (i) the first component and (ii) the second component may be configured as at least one of an electrical energy storage and a fuel cell module, and the other may be configured as a secondary braking system.

A system and method for generating vibrations in a fuel cell system include a vibration device which can be arranged on the fuel cell system or is formed by at least one component of the fuel cell system, for generating excitation vibrations which can be transmitted to the component. An electronic actuating system includes a controller and memory for actuating the vibration device, which may include a coolant pump or a compressor, at a natural frequency of a fuel system component for de-icing. At temperatures below 0° C., the electronic actuating system is adapted to actuate the vibration device during a switch-on process and/or a switch-off process of the fuel cell system taking into consideration at least one natural frequency of the component. Embodiments including actuating a compressor, cooling pump, and/or valve to transmit vibrations to a component to be de-iced at a natural frequency of the component.

A fault diagnostic apparatus for a fuel cell electric vehicle and a method therefor are provided. The apparatus includes: a main relay connected to a fuel cell stack; a power converter connected to the main relay; a heater relay connected to the fuel cell stack and the main relay at one end and connected to a cathode oxygen depletion (COD) heater at the other end; and a fuel cell control unit (FCU) connected with the main relay, the power converter, and the heater relay. The FCU diagnoses a fault of the main relay based on an amount of change in stack voltage according to control to turn off and on the heater relay and a power of the power converter according to variable control of a voltage of the power converter, when the vehicle enters a shutdown sequence, and outputs the diagnosed result.

A fault diagnostic apparatus for a fuel cell electric vehicle and a method therefor are provided. The apparatus includes: a main relay connected to a fuel cell stack; a power converter connected to the main relay; a heater relay connected to the fuel cell stack and the main relay at one end and connected to a cathode oxygen depletion (COD) heater at the other end; and a fuel cell control unit (FCU) connected with the main relay, the power converter, and the heater relay. The FCU diagnoses a fault of the main relay based on an amount of change in stack voltage according to control to turn off and on the heater relay and a power of the power converter according to variable control of a voltage of the power converter, when the vehicle enters a shutdown sequence, and outputs the diagnosed result.

A fuel cell system includes a fuel cell and a fuel cell controller. The fuel cell controller is configured to control a cooler based on a command from a host controller, the cooler being configured to cool the fuel cell. When a predetermined condition regarding the fuel cell is satisfied, the fuel cell controller controls the cooler according to a procedure predetermined in the fuel cell controller, regardless of the command from the host controller.