Patent application number | Description | Published |
20110293972 | FUEL CELL SYSTEM - A fuel cell system includes a fuel cell, a secondary battery, an oxidizing gas supplier, a gas supply flow regulator, an oxidizing gas supply path, a cathode off-gas exhaust path, a bypass flow path, a flow regulator, an available power output acquirer, and an operation controller, wherein the gas supply flow regulator regulates the gas supply flow rate to cause the oxidizing gas supplier to supply an excess gas flow rate, which is set to be greater than a target fuel gas-requiring gas flow rate, wherein the target fuel gas-requiring gas flow rate is the fuel cell-requiring gas flow rate to be supplied to the fuel cell in order to achieve the target current value, when the available power output is less than a minimum amount of electric power required for the oxidizing gas supplier to increase the gas supply flow rate from 0 to a preset gas flow rate within a preset time period, and the operation controller controls the flow regulator to make the bypass flow rate equal to a difference gas flow rate between the excess gas flow rate and the target fuel cell-requiring gas flow rate. | 12-01-2011 |
20120015270 | FUEL CELL SYSTEM - Provided is a fuel cell system including: a fuel cell which generates power by an electrochemical reaction between an oxidant gas supplied to an oxidant gas flow path and a fuel gas supplied to a fuel gas flow path; and a controller which adjusts an amount of the oxidant gas supplied to the fuel cell and a voltage of the fuel cell. The controller has an obstruction degree determining unit which determines a degree of obstruction of the oxidant gas flow path based on a stoichiometric ratio of the oxidant gas and the voltage of the fuel cell during a low-efficiency operation in which the stoichiometric ratio of the oxidant gas is reduced from the stoichiometric ratio of the oxidant gas during a normal operation and heat discharged from the fuel cell is increased from that during the normal operation. This improves stability of the low-efficiency operation of the fuel cell system. | 01-19-2012 |
20120015272 | FUEL CELL SYSTEM - 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. | 01-19-2012 |
20120100445 | FUEL CELL SYSTEM AND METHOD OF OPERATING FUEL CELL SYSTEM - The invention is provided to reliably restore generated voltage that has declined due to clogging of water in a fuel cell stack. A method of operating a fuel cell system having a fuel cell stack that generates electricity through an electrochemical reaction between a fuel gas including hydrogen gas and an oxidation gas, wherein when a generated voltage of the fuel cell stack declines, the water-in-cell content of the fuel cell stack is adjusted so that a variation in cell pressure loss in the fuel cell stack decreases based on a characteristic curve of the water-in-cell content of the fuel cell stack and the cell pressure loss of the fuel cell stack. | 04-26-2012 |
20120141898 | FUEL CELL SYSTEM - When starting operation of a fuel cell below the freezing point, a fuel cell system adjusts the open degree of a hydrogen pressure adjusting valve, introduces hydrogen to a hydrogen entrance of the fuel cell so as to make the total pressure of the hydrogen entrance is a first pressure, and starts a hydrogen circulation pump. If at least one of the cell voltages acquired by a cell voltmeter is below a predetermined voltage, the system determines that clogging is caused in a hydrogen flow channel in the fuel cell. When it is determined that clogging is present, the open degree of the pressure adjusting valve is adjusted and hydrogen is introduced to the hydrogen entrance so that the total pressure of the hydrogen entrance is a second pressure which is higher than the first pressure. Then, the hydrogen circulation pump is stopped and the fuel cell is warmed up to dissolve the clogging of the hydrogen flow channel. Thus, it is possible to suppress degradation of the fuel cell upon an operation start below the freezing point. | 06-07-2012 |
20120247746 | VEHICLE CONTROL APPARATUS AND VEHICLE CONTROL METHOD - The vehicle control apparatus configured to control a vehicle includes a fuel cell configured to supply electric power to the vehicle; an air conditioning mechanism having a heater core; a first medium circuit; a radiator installed in the first medium circuit; a bypass circuit formed in the first medium circuit to make a bypass flow of the cooling medium bypassing the radiator; a regulation valve installed in the first medium circuit to regulate a ratio of a flow rate of the cooling medium going through the radiator to a flow rate of the cooling medium going through the bypass circuit; a second medium circuit; a cooling medium circulation pump installed in at least one of the first medium circuit and the second medium circuit; a temperature acquisition module; a warm-up controller; and a state switchover structure. | 10-04-2012 |
20130040219 | FUEL CELL SYSTEM - 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 that is a current value of an operating point that is located on the current-voltage characteristic curve and satisfies a required heat value for the fuel cell with an output-based required current value that is a current value of an operating point that is located on the current-voltage characteristic curve and satisfies a required output for the fuel cell. 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. | 02-14-2013 |
20140205926 | FUEL CELL SYSTEM AND STARTING METHOD THEREOF - The problem is that a large force is required to open a flow-dividing shut valve provided in an air supply path for supplying the air to a fuel cell stack at a start of a fuel cell system. This problem is solved by reducing a pressure difference between upstream and downstream of the flow-dividing shut valve, before the flow-dividing shut valve is opened, at a start of the fuel cell system. | 07-24-2014 |
20140333316 | FUEL CELL SYSTEM - A fuel cell system comprises: a fuel cell formed of a plurality of cells stacked therein, each cell generating electric power through an electrochemical reaction between a fuel gas and an oxidant gas; a cell monitor capable of detecting a group voltage for each group wherein each group is composed of two or more cells; and an estimation device that estimates a minimum cell voltage. The estimation device comprises a maximum cell voltage estimation part that estimates a maximum cell voltage, and the estimation device estimates the minimum cell voltage by using an estimated value of the maximum cell voltage and a minimum group-average voltage, where an average voltage of a group having the lowest voltage value among the group voltages is defined as the minimum group-average voltage. | 11-13-2014 |
20140335435 | FUEL CELL SYSTEM, AND CONTROL METHOD FOR FUEL CELL SYSTEM - 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. | 11-13-2014 |
20150017561 | FUEL CELL SYSTEM - 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. | 01-15-2015 |