Toyota Jidosha Kabushiki Kaisha

Ryouichi Namba

Hiroyuki Tsunekawa

Masahiro Ito

Masashi Toida

Tomotaka Ishikawa

Shuya Kawahara

Norihiro Fukaya

Toshiyuki Sanada

Manabu Takahashi

Junichi Matsuo

Akihiro Kamiya

Yusuke Nishida

Koro Fujio

Asuka Takasaki

Mahiro Ozeki

Junichi Oura

Yoshihiro Ikogi

A fuel cell system includes a fuel cell stack and a control device that controls operation of the fuel cell system based on a measured voltage value measured by a voltage sensor. When the fuel cell system is started and a value measured by a temperature sensor is equal to or less than a temperature determined in advance, the control device raises the voltage of the fuel cell stack until a voltage condition determined in advance is met, by supplying a cathode with an oxidant gas before current sweep is started. The control device sets a voltage command value and a current command value such that an operation point of the fuel cell stack is on an equal power line of the fuel cell stack when the operation point is caused to transition in at least a part of a transition period.

Fuel cell system with improved low temperature operation

A fuel cell system includes a fuel cell in which cells are stacked, a voltage sensor that detects a voltage in unit of one or more of the cells, a control unit that determines an operating point of the fuel cell and causes the fuel cell to operate. The control unit causes the fuel cell to operate at a low efficiency operating point having a lower efficiency than an efficiency of a reference operating point in a warm-up operation. In the warm-up operation, the control unit calculates a total number of the cells in which the voltage detected by the voltage sensor is equal to or less than a predetermined first reference voltage and calculates an exhaust hydrogen concentration based on the total number or the cells.

Fuel cell system and method of controlling fuel cell system

The control device is configured so that when a temperature of the fuel cell at the time of start of power generation of the fuel cell is less than a standard temperature, it makes the fuel cell generate power so that the amount of heat generation of the fuel cell accompanying the power generation loss becomes a first amount of heat generation and so that when a cumulative value of current of a time period during which the fuel cell is made to generate power so that the amount of heat generation becomes the first amount of heat generation is equal to or greater than a predetermined cumulative value, it makes the fuel cell generate power so that the amount of heat generation becomes a second amount of heat generation larger than the first amount of heat generation.

Fuel cell system and control method for fuel cell system

The low efficiency power generation part of a control device is provided with an operating point setting part setting a target current and a target voltage defining an operating point of the fuel cell at the time of low efficiency power generation and a generated electric power control part making the generated electric power of the fuel cell increase and decrease at the time of low efficiency power generation by controlling the current of the fuel cell to the target current while making the flow rate of feed of oxidizing agent gas supplied to the fuel cell fluctuate so that the voltage of the fuel cell increases and decreases above and below the target voltage within a range where the charged and discharged electric powers of the rechargeable battery do not become larger than the allowable charged and discharged electric powers.

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.

A fuel cell system includes a fuel cell stack, an oxidizing gas supply system, a cooling medium circulation pump, a stack temperature acquisition unit, and a control unit. After a first time point when a change in an acquisition temperature turns from downward to upward after the change in the acquisition temperature turns from upward to downward for the first time after the start of the warm-up operation processing, the control unit sets a decrease speed in cases of decreasing a rotational speed of the cooling medium circulation pump to a smaller value than a value set before the first time point.

Fuel cell system

A cooling water temperature of a fuel cellis detected by a sensor. Based on the outside air temperature, a first threshold temperature and a second threshold temperature lower than the first threshold temperature are calculated. When it is judged that the cooling water temperature is lower than the first threshold temperature and higher than the second threshold temperature, first warmup processing is performed. When it is judged that the cooling water temperature is lower than the second threshold temperature, second warmup processing with an amount of heat generation greater than the first warmup processing is performed.

A braking control unit of a fuel cell vehicle is configured to, in a period during which the fuel cell vehicle is being braked in response to a braking request, (i) when an estimated amount of stagnant water is less than a predetermined second water amount less than a first water amount, limit an upper limit electric power of a regenerated electric power resulting from regenerative operation to a predetermined first value or below, and (ii) when the estimated amount of stagnant water is greater than or equal to the second water amount, execute an upper limit changing process of setting an upper limit electric power to a second value lower by a predetermined value than the first value.

Fuel cell vehicle

A fuel cell system includes a fuel cell stack and a control device. The control device raises the voltage of the fuel cell stack until a predetermined voltage condition is met, by supplying a cathode with an oxidant gas before current sweep is started when the fuel cell system is started and a value measured by a temperature sensor is equal to or less than a temperature determined in advance. The control device executes stand-by control, in which a current command value is kept constant, when a measured voltage value reaches a control start voltage value smaller than a voltage command value in a transition period, and ends the stand-by control by permitting a change in the current command value when the measured voltage value reaches a permission voltage value equal to or more than the voltage command value during execution of the stand-by control.

A fuel cell system includes: a fuel cell; a target operating point determination unit that determines a warm-up target operating point based on a required electric power amount during warm-up and a required heat generation amount during warm-up; an operation control unit; and a failure state identification unit that identifies whether an electric power consumption device that operates by consuming generated electric power generated by the fuel cell has failed. When a failure of the electric power consumption device is identified, the target operating point determination unit determines an operating point that satisfies a required electric power amount during a failure that is set to be smaller than the required electric power amount during the warm-up and a required heat generation amount during the failure that is set to be smaller than the required heat generation amount during the warm-up as a target operating point during the failure.

Fuel cell system, control method of fuel cell system, and storage medium

A fuel cell system includes a fuel cell stack, a temperature measurement unit, and a controller. The controller is configured to, when the stack temperature is equal to or lower than a predetermined first threshold temperature at the time of startup of the fuel cell system, control a heat generation amount per unit time of the fuel cell stack to a set heat generation amount to perform a warming-up operation until the stack temperature increases to a target temperature, and when the stack temperature is equal to or higher than a predetermined second threshold temperature, execute at least one of setting the target temperature to be lower than the target temperature when the stack temperature is lower than the second threshold temperature and setting the set heat generation amount to be smaller than the set heat generation amount when the stack temperature is lower than the second threshold temperature.

A fuel cell system includes a fuel cell stack, an oxidizing gas supply system, a fuel gas supply system, a current control circuit configured to control an output current of the fuel cell stack, a control unit configured to control power generation of the fuel cell stack, and the output current of the current control circuit, the control unit controlling the current control circuit to adjust the output current thereby adjusting a heating value of the fuel cell stack; and a monitoring unit configured to monitor abnormal fuel gas generation, the abnormal fuel gas generation corresponding to a state where the fuel gas in excess of a predetermined allowable amount exists in the cathode. When the monitoring unit detects the abnormal fuel gas generation during execution of a warm-up operation to allow the fuel cell stack to generate heat with a predetermined target heating value, the control unit reduces the output current by reducing the target heating value.

Fuel cell system and control method thereof

A fuel cell system includes a control unit that is configured to perform highland control for increasing an amount of electric power generated per unit time by a fuel cell and increasing a rotational speed of a compressor such that an operating point of the compressor falls outside a surging region, in comparison with a case where a highland condition that an outside air pressure determined from an outside air pressure-associated information is lower than an outside air pressure threshold determined in advance is not fulfilled, when the highland condition is fulfilled in starting electric power generation by the fuel cell.

Fuel cell system and method of controlling the same

A fuel cell system includes a fuel cell, an oxidant gas supply and discharge system, a coolant circulation system, a compressor, an atmospheric pressure sensor, and a control unit. When a measured atmospheric pressure becomes lower than a predetermined reference atmospheric pressure, the control unit executes temperature and pressure lowering control for controlling the coolant circulation system to lower the temperature of the fuel cell while controlling a pressure-regulating valve to lower a delivery pressure of the compressor.

Growing community of inventors

Okazaki, Japan

Ryouichi Namba