Toyota Jidosha Kabushiki Kaisha

Tsuyoshi Maruo

Tomohiro Ogawa

Yoshiaki Naganuma

Masashi Toida

Hiroyuki Tsunekawa

Takashi Yamada

Mitsuhiro Nada

Hiroyuki Imanishi

Shun Matsumoto

Tomotaka Ishikawa

Tomio Yamanaka

Seiichi Tanaka

Hiroyuki Suzuki

Masahiro Ito

Manabu Kato

Makoto Mori

Hideyuki Kumei

Shuya Kawahara

Satoshi Shiokawa

Osamu Hamanoi

Tomoaki Uchiyama

Shuhei Nakamura

Shinji Asou

A fuel cell system includes a fuel cell including a plurality of stacked cells, a fuel gas supply unit configured to supply fuel gas to a supply port of the fuel cell and return the fuel gas exhausted through an exhaust port of the fuel cell, and a controller configured to control an operation of the fuel gas supply unit. The controller is configured to execute a drain process for draining residual water accumulated in the fuel cell through the exhaust port. In the drain process, a first process in which the fuel gas is supplied to the fuel cell until a pressure in the fuel cell reaches a predetermined threshold pressure and a second process in which the pressure in the fuel cell is reduced after the first process are repeatedly executed.

Fuel cell system

A fuel cell system includes a fuel cell, a hydrogen tank, a hydrogen supply passage connecting the hydrogen tank and the fuel cell, a cutoff valve configured to cut off circulation of hydrogen in the hydrogen supply passage, a detection unit configured to detect a start of filling of the hydrogen tank with hydrogen, and a purge controller configured to close the cutoff valve in a case where the fuel cell system is stopped and the detection unit detects the start of filling with hydrogen in a state in which purge processing of purging the in-cell hydrogen flow passage is to be executed, and to execute processing of purging the in-cell hydrogen flow passage by causing hydrogen remaining on a downstream side of the cutoff valve in a hydrogen flow in the hydrogen supply passage to flow in the in-cell hydrogen flow passage as the purge processing.

Fuel Cell System

A fuel cell system includes a controller that controls actions of the fuel cell system. The controller includes a freezing presence-absence determination unit that performs freezing presence-absence determination, a temperature raising execution unit that performs temperature raising processing for raising a temperature of an exhaust and drain valve, and a thawing presence-absence determination unit. In the freezing presence-absence determination, freezing determination is made when the exhaust flow rate of gas is equal to or lower than a first threshold. In the thawing presence-absence determination, thawing determination indicating that the exhaust and drain valve is thawed is made when the exhaust flow rate of gas is higher than a second threshold. The second threshold shows a flow rate higher than the first threshold.

A fuel cell system includes a fuel cell a current sensor that detects a current of the fuel cell, a plurality of cell voltage sensors that detects a voltage in a unit of one or two or more cells of the fuel cell among the cells, a pump that adjusts a flow rate of the cooling medium, and a controller. The controller estimates, in a first case, a calorific value of the fuel cell using each detected cell voltage value and the detected current value, decides the flow rate of the cooling medium based on the estimated calorific value, and controls the operation of the pump such that the flow rate of the cooling medium is lower than that of a case where the estimated calorific value is the same in a normal operation of the fuel cell.

A fuel cell system comprises: a gas-liquid separator separating exhaust gas of a fuel cell stack into a liquid component and a gas component and storing liquid water of the liquid component; a circulation pipe; a drain pipe discharging the liquid water; and a drain valve opening and closing the drain pipe. In an end scavenging process that is executed when operation of the fuel cell system is finished, the control unit opens the drain valve when a valve opening condition for the drain valve is satisfied. The valve opening condition is set such that an amount of the liquid water stored in the gas-liquid separator at the time the drain valve is opened in the end scavenging process is larger than an amount of the liquid water stored in the gas-liquid separator at the time the drain valve is opened during normal operation of the fuel cell system.

Fuel cell system and method for controlling fuel cell system

Provided is a fuel cell system that can effectively suppress clogging of a pipe due to freezing of water in a fuel gas supply system thereof without the need for halting the operation of the fuel cells, and thus is highly reliable. When possible freezing of water is detected or presumed to be present downstream of an injector, the amount of a fuel gas to be supplied from a circulation pump that is disposed in a circulation channel is relatively increased compared to the amount of the fuel gas to be supplied from the injector.

A fuel cell system comprises a fuel cell; a reactive gas supply mechanism configured to supply a reactive gas to the fuel cell; a discharge flow path configured to discharge an off-gas and water discharged from the fuel cell; a valve provided in the discharge flow path; a remaining water purging controller configured to control a remaining water purging process of the fuel cell by using the reactive gas supply mechanism and the valve; a heating portion configured to heat the valve; and a failure detector configured to detect a failure of the heating portion. When a failure of the heating portion is detected, the remaining water purging controller performs the remaining water purging process and increases a water discharge power in the remaining water purging process than a water discharge power in the remaining water purging process performed when no failure of the heating portion is detected.

Fuel cell system and remaining water purging control method

An object is to maintain the voltage of a fuel cell at a desired voltage level and suppress a voltage variation, even in the case of a low load request. A power supply system including a fuel cell causes at least part of a required electric power to be supplied from the fuel cell in an ordinary load state. In a low load state, the power supply system supplies an amount of oxygen that is required to make the voltage of the fuel cell equal to a predetermined target voltage and that is less than an amount of oxygen supplied to the fuel cell in the ordinary load state, to the fuel cell. In a first low load state, the power supply system sets the target voltage to a first target voltage and supplies oxygen to the fuel cell. After a subsequent shift to a state that the required electric power becomes higher than a predetermined reference value to cause the fuel cell to generate electric power at an output voltage that is higher than the first target voltage, in a further shift to a second low load state, the power supply system sets the target voltage to a second target voltage that is higher than the first target voltage and supplies oxygen to the fuel cell.

Power supply system and voltage control method of fuel cell

A fuel cell system comprises: a fuel cell; a cooling system circuit including a cooling liquid supply path configured to supply a cooling liquid to the fuel cell, a radiator configured to cool down the cooling liquid, a radiator fan, and a cooling liquid pump provided in the cooling liquid supply path to feed the cooling liquid to the fuel cell; a controller; and a speedometer configured to obtain a speed of the fuel cell vehicle, wherein the controller is capable of performing a first cooling control that sets an upper limit value of driving amount of the radiator fan according to the speed of the fuel cell vehicle and regulates a flow rate of the cooling liquid pump or the driving amount of the radiator fan under the upper limit value of the driving amount of the radiator, so as to cool down the fuel cell.

Fuel cell system, fuel cell vehicle and control method of fuel cell system

A fuel cell system includes a fuel cell stack having a plurality of cells each having hydrogen channels, a hydrogen channel inlet, and a hydrogen channel outlet, a load supplied with power from the fuel cell stack, a circulation passage connecting the channel inlet with the channel outlet, a hydrogen pump provided in the circulation passage, and a controller. The controller rotates the hydrogen pump in a positive direction so as to feed the hydrogen gas in a first amount into each cell through the channel inlet, at a flow rate larger than a minimum flow rate required for power generation, and then rotate the hydrogen pump in a negative direction so as to feed the hydrogen gas into each cell through the channel outlet, during a period from stop of power supply to the load, to the next start of power supply.

Fuel cell system and method of controlling the same

The method comprises: determining whether or not an inlet temperature is equal to or above a lower-limit temperature of a temperature range in which generated water does not freeze within the fuel cell; and adjusting the flow rate of the cooling medium in the circulation flow path to become more than the normal flow rate when it is determined that the inlet temperature is equal to or above the lower-limit temperature, and adjusting the flow rate of the cooling medium in the circulation flow path to be equal to or below the normal flow rate when it is determined that the inlet temperature is not equal to or above the lower-limit temperature.

Flow control method of cooling medium in a fuel cell system, and fuel cell system

A fuel cell system comprises: a fuel cell; a cooling liquid supply flow path for supplying cooling liquid to the fuel cell; a radiator for cooling the cooling liquid; a first temperature sensor, provided at an outlet of the radiator, for measuring a temperature of the cooling liquid; an ambient temperature sensor; and a controller. The controller executes: estimating a temperature of the cooling liquid inside the cooling liquid supply flow path based on an ambient temperature measured by the ambient temperature sensor; acquiring a temperature of the cooling liquid inside the cooling liquid supply flow path based on the temperature measured by the first temperature sensor after it is determined that the cooling liquid within the radiator has reached the first temperature sensor; and adjusting a flow rate of the cooling liquid based on the estimated temperature or the acquired temperature of the cooling liquid.

Fuel cell system, fuel cell mountable vehicle and method of controlling fuel cell system

An object is to suppress drying of a fuel cell during continuous operation with high load. There is provided a fuel cell system including a fuel cell. The fuel cell system comprises an impedance detector that is configured to detect an impedance of the fuel cell; and a current limiter that is configured to limit an output current of the fuel cell with a limiting rate. The current limiter changes the limiting rate, based on the detected impedance.

Fuel cell system and control method thereof

At an ordinary stop time of a fuel cell system, a controller of the fuel cell system completes an ordinary stop process that includes at least one of a water drainage process that discharges water from at least one of the fuel gas flow path and the oxidizing gas flow path and a cathode sealing process that seals the oxidizing gas flow path, and subsequently stops the fuel cell system. When the fuel cell system satisfies a predetermined emergency stop condition, the controller does not perform at least part of the ordinary stop process but performs an emergency stop process that sets the fuel cell system to be restarted after elapse of a first time period since a stop of the fuel cell system and subsequently stops the fuel cell system. The controller restarts the fuel cell system after elapse of the first time period since stop of the fuel cell system and performs a restart process that performs the ordinary stop process.

Fuel cell system and emergency stop method

The operation control method of a fuel cell includes acquiring a startup temperature of the fuel cell; acquiring a present temperature of the fuel cell; setting a present target operation point of the fuel cell that is identified by an output voltage value and an output current value based on the startup temperature, or based on the startup temperature and the present temperature; controlling at least one of the flow of the reaction gas supplied to the fuel cell, and an output voltage of the fuel cell so that the operation point of the fuel cell becomes the target operation point, and setting the target operation point includes a process of setting an operation point having a low output voltage value as the target operation point when the startup temperature is low as compared to the case when the startup temperature is high, if the present temperature is the same.

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Toyohashi, Japan

Tsuyoshi Maruo