Abstract: Provided is a fuel cell system configured to accurately control the gas flow rate and pressure ratio of a turbo-type air compressor. The fuel cell system is a fuel cell system comprising: a fuel cell, an air compressor, an oxidant gas supply flow path, an oxidant gas discharge flow path, an oxidant gas outlet valve, a bypass flow path, a bypass valve, an atmospheric pressure sensor, an outside temperature sensor, a flow rate sensor, a rotational frequency sensor, an angle sensor, a controller, and a calculator configured to estimate the flow resistance Zd, total pressure, partial pressure and energy of each of members that are the air compressor, the oxidant gas outlet valve and the bypass valve.

Abstract: A system for controlling gas flow in a fuel cell circuit includes a fuel cell stack, a pressure sensor, and a valve to adjust a flow of gas through the fuel cell circuit. The system further includes an ECU designed to estimate pressure values of the gas at multiple locations in the fuel cell circuit based on the detected pressure of the gas and based on flow resistance values (including at the valve), the estimated pressure values including an estimated sensor pressure value at a location of the pressure sensor. The ECU is further designed to determine a pressure deviation between the detected pressure and the estimated sensor pressure value. The ECU is further designed to adjust the flow resistance value of the valve to determine a final flow resistance value of the valve that causes the pressure deviation to reach or drop below a threshold deviation amount.

Abstract: A fuel cell system includes a fuel cell stack, a fuel gas supply path, an injector, an ejector, a circulation path, a pressure difference detection unit that detects a pressure difference between an ejector inlet port pressure and an ejector outlet port pressure, and a control device. The control device calculates a required circulation flow rate that is required for a fuel off gas supplied from the fuel cell stack to the ejector, based on a required load for the fuel cell stack, calculates an estimated circulation flow rate that is an estimated flow rate of the fuel off gas supplied from the fuel cell stack to the ejector, based on the required load and the pressure difference, and increases the flow rate of a fuel gas supplied from the injector to the fuel cell stack when the estimated circulation flow rate is lower than the required circulation flow rate.

Abstract: A fuel cell system is equipped with a control unit that controls a rotational speed of the turbo compressor that supplies air to an air supply flow passage and an opening degree of at least one valve that adjusts a flow rate and a pressure of the air supplied to a fuel cell such that an operating point of the turbo compressor becomes a target operating point. The control unit sets the target operating point within an operating point range that is on the higher flow rate side than at least part of a first region where an amount of change in flow rate is larger than a predetermined value when a pressure ratio of the turbo compressor is changed by a predetermined amount at a same rotational speed, on a higher flow rate side than a surging region, when a predetermined condition is fulfilled.

Abstract: A fuel cell system includes a fuel cell stack, a fuel gas supply path, an injector, an ejector, a circulation path, an outlet port pressure detection unit, and a control device. The control device stops driving the injector when an ejector outlet port pressure is equal to or more than a required upper limit value with the injector driven, and drives the injector when the ejector outlet port pressure is equal to or less than a required lower limit value with the injector stopped. The control device reduces the required upper limit value stepwise and reduces the required lower limit value stepwise in a range defined by a first target upper limit value and a second target upper limit value when a required load is varied from a first required load to a second required load and a load reduction amount is more than a first predetermined load.

Abstract: Systems and methods for controlling fluid flow in a fuel cell circuit of a vehicle. A system may have a fuel cell stack configured to receive hydrogen gas. The system may have a current sensor configured to detect current flowing through the fuel cell stack. The system may have a plurality of actuators, which may include at least one injector, a pump, and a shut valve. The system may have an electronic control unit (ECU). The ECU may estimate pressures of the hydrogen gas and non-hydrogen gases in the circuit. The ECU may determine a current increase rate based on the detected current. The ECU may apply a compensatory hydrogen gas stoic to a base hydrogen gas stoic to meet a target hydrogen gas stoic by controlling one or more of the actuators based on the estimated pressures when the current increase rate is above a predetermined threshold value.

Abstract: A fuel cell system includes a fuel cell, a fuel gas supply channel, a regulator, an injector, and a controller. The controller drives the regulator in conjunction with the injector. The controller compares a fuel gas flow amount necessary for the fuel cell to generate electricity with a predetermined fuel gas flow amount, selects the fuel gas flow amount that is larger, and issues commands to the regulator and the injector. The predetermined fuel gas flow amount is set to be larger than the fuel gas flow amount necessary for the fuel cell to generate the electricity when a generated current or output of the fuel cell is smaller than a predetermined threshold value.

Abstract: Systems and methods for controlling fluid flow in a fuel cell circuit of a vehicle. A system may have a fuel cell stack configured to receive hydrogen gas. The system may have a current sensor configured to detect current flowing through the fuel cell stack. The system may have a plurality of actuators, which may include at least one injector, a pump, and a shut valve. The system may have an electronic control unit (ECU). The ECU may estimate pressures of the hydrogen gas and non-hydrogen gases in the circuit. The ECU may determine a current increase rate based on the detected current. The ECU may apply a compensatory hydrogen gas stoic to a base hydrogen gas stoic to meet a target hydrogen gas stoic by controlling one or more of the actuators based on the estimated pressures when the current increase rate is above a predetermined threshold value.

Abstract: A fuel cell system includes a fuel cell stack, a fuel gas supply path, an injector, an ejector, a circulation path, a pressure difference detection unit that detects a pressure difference between an ejector inlet port pressure and an ejector outlet port pressure, and a control device. The control device calculates a required circulation flow rate that is required for a fuel off gas supplied from the fuel cell stack to the ejector, based on a required load for the fuel cell stack, calculates an estimated circulation flow rate that is an estimated flow rate of the fuel off gas supplied from the fuel cell stack to the ejector, based on the required load and the pressure difference, and increases the flow rate of a fuel gas supplied from the injector to the fuel cell stack when the estimated circulation flow rate is lower than the required circulation flow rate.

Abstract: A fuel cell system includes a fuel cell stack, a fuel gas supply path, an injector, an ejector, a circulation path, an outlet port pressure detection unit, and a control device. The control device stops driving the injector when an ejector outlet port pressure is equal to or more than a required upper limit value with the injector driven, and drives the injector when the ejector outlet port pressure is equal to or less than a required lower limit value with the injector stopped. The control device reduces the required upper limit value stepwise and reduces the required lower limit value stepwise in a range defined by a first target upper limit value and a second target upper limit value when a required load is varied from a first required load to a second required load and a load reduction amount is more than a first predetermined load.

Abstract: A system for controlling gas flow in a fuel cell circuit includes a fuel cell stack, a pressure sensor, and a valve to adjust a flow of gas through the fuel cell circuit. The system further includes an ECU designed to estimate pressure values of the gas at multiple locations in the fuel cell circuit based on the detected pressure of the gas and based on flow resistance values (including at the valve), the estimated pressure values including an estimated sensor pressure value at a location of the pressure sensor. The ECU is further designed to determine a pressure deviation between the detected pressure and the estimated sensor pressure value. The ECU is further designed to adjust the flow resistance value of the valve to determine a final flow resistance value of the valve that causes the pressure deviation to reach or drop below a threshold deviation amount.

Abstract: Provided is a fuel cell system configured to accurately control the gas flow rate and pressure ratio of a turbo-type air compressor. The fuel cell system is a fuel cell system comprising: a fuel cell, an air compressor, an oxidant gas supply flow path, an oxidant gas discharge flow path, an oxidant gas outlet valve, a bypass flow path, a bypass valve, an atmospheric pressure sensor, an outside temperature sensor, a flow rate sensor, a rotational frequency sensor, an angle sensor, a controller, and a calculator configured to estimate the flow resistance Zd, total pressure, partial pressure and energy of each of members that are the air compressor, the oxidant gas outlet valve and the bypass valve.

Abstract: A fuel cell system includes a fuel cell, a fuel gas supply channel, a regulator, an injector, and a controller. The controller drives the regulator in conjunction with the injector. The controller compares a fuel gas flow amount necessary for the fuel cell to generate electricity with a predetermined fuel gas flow amount, selects the fuel gas flow amount that is larger, and issues commands to the regulator and the injector. The predetermined fuel gas flow amount is set to be larger than the fuel gas flow amount necessary for the fuel cell to generate the electricity when a generated current or output of the fuel cell is smaller than a predetermined threshold value.

Abstract: A fuel cell system is equipped with a control unit that controls a rotational speed of the turbo compressor that supplies air to an air supply flow passage and an opening degree of at least one valve that adjusts a flow rate and a pressure of the air supplied to a fuel cell such that an operating point of the turbo compressor becomes a target operating point. The control unit sets the target operating point within an operating point range that is on the higher flow rate side than at least part of a first region where an amount of change in flow rate is larger than a predetermined value when a pressure ratio of the turbo compressor is changed by a predetermined amount at a same rotational speed, on a higher flow rate side than a surging region, when a predetermined condition is fulfilled.

Abstract: A fuel cell system includes: a fuel cell supplied with fuel gas for power generation; a fuel supply flow passage flowing fuel gas, supplied from a fuel supply source, to the fuel cell; a pressure regulating valve regulating a pressure of fuel gas flowing through the fuel supply flow passage; a fuel circulation flow passage returning gas, emitted from the fuel cell, to the fuel supply flow passage; a circulation pump delivering gas in the fuel circulation flow passage to the fuel supply flow passage; an emission valve emitting gas in the fuel circulation flow passage to an outside; and a control device controlling the pressure regulating valve, the circulation pump and the emission valve such that the sum of losses of crossover hydrogen, circulation pump power and purge hydrogen is minimum while a hydrogen stoichiometric ratio required for power generation of the fuel cell is ensured.

Abstract: A fuel cell system suppresses the deterioration of an electrolyte membrane of a fuel cell. The fuel cell system comprises: a temperature rise speed calculation unit for calculating a target temperature rise speed of the fuel cell using a temperature of the fuel cell and a water content of the fuel cell; and a drive control unit for controlling a drive of the cooling water pump using the temperature rise speed of the fuel cell and the target temperature rise speed calculated by the temperature rise speed calculation unit. The drive control unit controls the drive of the cooling water pump such that a circulation amount of the cooling water is decreased when the temperature rise speed of the fuel cell is below the target temperature rise speed and controls the drive of the cooling water pump such that the circulation amount of the cooling water is increased when the temperature rise speed of the fuel cell is equal to or greater than the target temperature rise speed.

Abstract: A fuel cell system suppresses the deterioration of an electrolyte membrane of a fuel cell. The fuel cell system comprises: a temperature rise speed calculation unit for calculating a target temperature rise speed of the fuel cell using a temperature of the fuel cell and a water content of the fuel cell; and a drive control unit for controlling a drive of the cooling water pump using the temperature rise speed of the fuel cell and the target temperature rise speed calculated by the temperature rise speed calculation unit. The drive control unit controls the drive of the cooling water pump such that a circulation amount of the cooling water is decreased when the temperature rise speed of the fuel cell is below the target temperature rise speed and controls the drive of the cooling water pump such that the circulation amount of the cooling water is increased when the temperature rise speed of the fuel cell is equal to or greater than the target temperature rise speed.

Abstract: A fuel cell system includes: a fuel cell supplied with fuel gas for power generation; a fuel supply flow passage flowing fuel gas, supplied from a fuel supply source, to the fuel cell; a pressure regulating valve regulating a pressure of fuel gas flowing through the fuel supply flow passage; a fuel circulation flow passage returning gas, emitted from the fuel cell, to the fuel supply flow passage; a circulation pump delivering gas in the fuel circulation flow passage to the fuel supply flow passage; an emission valve emitting gas in the fuel circulation flow passage to an outside; and a control device controlling the pressure regulating valve, the circulation pump and the emission valve such that the sum of losses of crossover hydrogen, circulation pump power and purge hydrogen is minimum while a hydrogen stoichiometric ratio required for power generation of the fuel cell is ensured.

Abstract: A fuel cell system suppresses the deterioration of an electrolyte membrane of a fuel cell. The fuel cell system comprises: a temperature rise speed calculation unit for calculating a target temperature rise speed of the fuel cell using a temperature of the fuel cell and a water content of the fuel cell; and a drive control unit for controlling a drive of the cooling water pump using the temperature rise speed of the fuel cell and the target temperature rise speed calculated by the temperature rise speed calculation unit. The drive control unit controls the drive of the cooling water pump such that a circulation amount of the cooling water is decreased when the temperature rise speed of the fuel cell is below the target temperature rise speed and controls the drive of the cooling water pump such that the circulation amount of the cooling water is increased when the temperature rise speed of the fuel cell is equal to or greater than the target temperature rise speed.

Abstract: A fuel cell system includes a fuel cell, an operation controller and an air-conditioning mechanism. In response to a heating request for the air-conditioning mechanism during ordinary operation where the fuel cell is operated at an operating point on a current-voltage characteristic curve of the fuel cell, the operation controller compares a heat value-based required current value with an output-based required current value. When the output-based required current value is equal to or greater than the heat value-based required current value, the operation controller causes the fuel cell to be operated at an operating point on the current-voltage characteristic curve. When the output-based required current value is smaller than the heat value-based required current value, the operation controller controls the operating point of the fuel cell to an operating point of lower power generation efficiency than that of the operating point on the current-voltage characteristic curve.