A voltage control system includes: a converter controlling portion; a current value acquisition portion; and a voltage value acquisition portion. The converter controlling portion sets a duty ratio in a present cycle by adding an addition term to a feedforward term, the addition term being determined by use of a current deviation, which is a difference between a target value of an output current in the present cycle and a current measured value in a previous cycle, and the duty ratio in the previous cycle, the addition term being corresponding to an increase of the output current in the present cycle.

An electric power supply device supplies electric power to a work machine having an electric power source. The electric power supply device includes a fuel cell different from the electric power source and an electric power connecting section for transferring electric power between the electric power source and the electric power supply device. A control device for controlling the electric power supply device includes a rated capability obtaining section for obtaining the information indicating the rated value of the charge and discharge capability of the electric power source of the work machine in response to the electric power supply device being mounted in the work machine or the electric power supply device being able to utilize the electric power of the electric power source, and an operating condition determining section for determining the operating condition of the electric power supply device based on the rated value.

A fuel cell system may include: a fuel cell; a hydrogen gas supply passage; a solenoid valve that changes an opening degree of the hydrogen gas supply passage; a pressure sensor that detects a pressure in a downstream supply passage being a part of the hydrogen gas supply passage from the solenoid valve to the fuel cell; and a control circuit. The control circuit detects a rise in the pressure detected by the pressure sensor when increasing a conducted electric current conducted in the solenoid valve from a state where the solenoid valve is closed, and detection of a rising current which is the conducted electric current at a time of the rise in the pressure; and calculates an increase characteristic based on the rising current, the increase characteristic being a relationship between the conducted electric current and the pressure when the conducted electric current increases.

A fuel cell system may include a fuel cell; a hydrogen gas supply passage configured to supply hydrogen gas to the fuel cell; a solenoid valve configured to change an opening degree of the hydrogen gas supply passage; a pressure sensor configured to detect a pressure in a downstream supply passage which is a part of the hydrogen gas supply passage from the solenoid valve to the fuel cell; and a control circuit configured to control the solenoid valve. The control circuit may be configured to perform: detecting and storing a conducted electric current conducted in the solenoid valve and the pressure at plural points while changing the conducted electric current at a first sweep speed; and detecting and storing the conducted electric current and the pressure at plural points while changing the conducted electric current at a second sweep speed different from the first speed.

A fuel cell system wherein the fuel cell comprises an electrolyte membrane; wherein the electrolyte membrane is a perfluorosulfonic acid (PFSA) membrane; wherein the controller has a data group showing a correlation between the current of the fuel cell and the temperature of the fuel cell which is necessary to keep a moisture content of the electrolyte membrane at a predetermined moisture content threshold or more; and wherein, when the temperature and voltage of the fuel cell become a predetermined first temperature threshold or more and a predetermined voltage threshold or more, respectively, the controller conducts a temperature dropping time power generation mode in which power generation is conducted while controlling the current of the fuel cell with reference to the data group, until the temperature of the fuel cell becomes a predetermined second temperature threshold which is lower than the first temperature threshold.

An information processing device includes an acquisition unit which acquires use history information indicating a use history of a vehicle, a prediction unit which predicts an output decrease amount based on use history information acquired by the acquisition unit and output decrease characteristic information indicating an output decrease characteristic of a fuel cell in the vehicle according to the use history, and a control unit which executes predetermined processing based on the output decrease amount predicted by the prediction unit. The control unit executes processing of predicting a deterioration time at which a rated output of the fuel cell is equal to or smaller than a threshold value based on changes in the output decrease amount from start of use of the vehicle to present, and outputting information indicating the deterioration time.

A fuel cell vehicle includes a first current amount calculating unit that calculates a first total amount of current output from a fuel cell during a period from a predetermined timing to the present time, a hydrogen amount calculating unit that calculates a hydrogen total amount output from a hydrogen tank during the period from the predetermined timing to the present time, a remaining amount acquisition unit that acquires a hydrogen remaining amount in the hydrogen tank, and a current amount prediction unit that predicts a current amount that can be supplied by the fuel cell based on the first total amount, the total amount, and the hydrogen remaining amount.

A control device switches between a first injection control of injecting the fuel gas by sequentially providing periods during which at least one of the plurality of injectors injects the fuel gas if it is determined that the power generation state of the fuel cell stack is stable based on a detected power generation state, and a second injection control of injecting the fuel gas by intermittently providing periods during which the plurality of injectors simultaneously inject the fuel gas if it is determined that the power generation state of the fuel cell stack is not stable based on the detected power generation state.

Disclosed is a performance evaluation apparatus of a fuel cell electrode. The performance evaluation apparatus includes a working electrode unit configured such that a working electrode is disposed therein, gas is supplied to an inside of the working electrode unit, and voltage and current are measured by a current collection rod, a counter electrode unit provided to guide mounting of the working electrode unit so that a counter electrode faces the working electrode, and configured to store an electrolyte solution, current is measured by the current collection rod, and voltage is measured by a reference electrode immersed in the electrolyte solution, a heater unit immersed in the electrolyte solution to heat the electrolyte solution, and a control unit configured to selectively adjust a temperature of the heater unit within a set temperature range, and to evaluate performance of the working electrode.

Provided herein are methods for operating carbon oxide (COX) reduction reactors (CRR) and related apparatus. In some embodiments, the methods involve shutting off, reducing, or otherwise controlling current during various operation stages including hydration, break-in, normal operation, planned shut-offs, and extended shutoff or storage periods.