A fuel cell system with a plurality of fuel cell modules connected to form a fuel cell group having first and second electrical supply terminals that terminate to an electrical load; a measuring device connected to the fuel cell modules that measures a load current of the respective fuel cell modules; and a controller that detects a respective operating state of the fuel cell modules. The controller is connected to and controls operation of the fuel cell modules, and detects whether the operating state is in a respective partial load range of the respective fuel cell module. The controller provides a load current demanded by the load in a first partial-load operating mode of the load by operating all fuel cell modules of the fuel cell group such that all of the fuel cell modules are within the respective partial load range of the respective fuel cell module.

An electric power adjustment system includes: a power storage system that is configured to store electric power; a reversible fuel cell system that is configured to generate electric power through a chemical reaction in a fuel cell using hydrogen which is supplied from a hydrogen station configured to store hydrogen and supply the generated electric power to the power storage system and that is configured to produce hydrogen through water electrolysis in the fuel cell and supply the produced hydrogen to the hydrogen station; a power adjustment device that is configured to adjust a flow of electric power which is exchanged between the power storage system and the reversible fuel cell system; and a power management device that is configured to manage the flow of electric power in the power adjustment device.

During performance of low efficiency power generation, a control device controls the flow rate of feed of the oxidizing agent gas so that the amount of heat generation of the fuel cell accompanying power generation loss becomes a first amount of heat generation when the state of a mount on which the fuel cell system is mounted is a first mode and controls the flow rate of feed of the oxidizing agent gas so that the amount of heat generation becomes a second amount of heat generation smaller than the first amount of heat generation when the state of the mount is a second mode where the generated electric power of the fuel cell fluctuates more easily compared with the first mode.

The control device is provided with a power generation part configured to be able to selectively perform normal power generation and low efficiency power generation in which the power generation loss is greater compared with normal power generation when there is a request for warmup of the fuel cell. The power generation part temporarily stops the low efficiency power generation and performs normal power generation when during performance of the low efficiency power generation the target generated electric power of the fuel cell becomes equal to or greater than a predetermined first switching electric power.

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.

A control system and a control method of fuel cell stacks are provided. The control system includes a set of fuel cell stacks, a secondary battery, a monitoring device, and a control device. Each fuel cell stack has a power output that can be independently started up or shut down. The secondary battery is connected to power output terminals of the fuel cell stacks via a power transmission path. The monitoring device is configured to monitor an electrical parameter of the power transmission path. The control device receives an electrical parameter signal from the monitoring device, and outputs a control signal to shut down or start up the power output of at least one of the fuel cell stacks if the electrical parameter's value is higher than a predetermined upper limit or lower than a predetermined lower limit.

A fuel cell system herein may include a battery configured to supply electric power to a fuel cell auxiliary device used for activating a fuel cell stack. When remaining electric energy in the battery is higher than an electric energy threshold upon activation of the fuel cell stack, a controller of the fuel cell system may start outputting current from the fuel cell stack after a fuel concentration in the fuel cell stack reaches a predetermined fuel concentration threshold, and when the remaining electric energy decreases below the electric energy threshold while the fuel concentration is being increased, the controller may start outputting current from the fuel cell stack regardless of the fuel concentration in the fuel cell stack. The current can be obtained from the fuel cell stack even when the remaining electric energy in the battery is low.

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 cold start control method for a fuel cell is provided. The method includes determining whether a cold start condition upon start on is satisfied and estimating thawing energy required to thaw frozen moisture inside a fuel cell stack when the cold start condition has been satisfied. A thawing control SOC of a high-voltage battery is calculated based on the estimated thawing energy. The cooling water inside a cooling water line for cooling the fuel cell stack is heated by using a heater having received power from the high-voltage battery when the current SOC of the high-voltage battery is equal to or less than a thawing control SOC.