Abstract: 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.

Abstract: 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.

Abstract: A fuel cell system includes a plurality of fuel cell units each including a fuel cell, a fuel cell cooling system having a heat exchanger that exchanges heat between a primary-side coolant, and a secondary-side coolant flowing through the fuel cell, and a coolant pump that adjusts the flow rate of the secondary-side coolant, and a controller that controls the fuel cell, a cooling device, and a cooling system that supplies the primary-side coolant from the cooling device to each fuel cell unit. During stop of operation of the fuel cell system, the cooling device supplies the primary-side coolant having a temperature equal to or higher than a predetermined temperature to each fuel cell unit, and the controller activates the coolant pump to cause the secondary-side coolant to flow through the heat exchanger, in one or more fuel cell units in which the fuel cell has a possibility of freezing.

Abstract: A refrigeration cycle apparatus is a refrigeration cycle apparatus having a refrigerant circuit having a compressor, a condenser, a supercooler, an expansion device, and an evaporator connected by a refrigerant pipe, and configured to circulate refrigerant containing refrigerant having a temperature gradient, wherein the supercooler sets a degree of supercooling of the refrigerant, which is a temperature difference between a temperature from the condenser to a refrigerant flow inlet of the supercooler and a temperature in a refrigerant flow outlet on a downstream side of the supercooler, to be larger than the temperature gradient generated at a time of refrigerant shortage of the refrigerant between the refrigerant flow inlet and the refrigerant flow outlet of the supercooler, the refrigeration cycle apparatus including a refrigerant amount determination unit configured to compare a determination threshold value set to a value larger than the temperature gradient of the refrigerant with the degree of supercoo

Abstract: A refrigeration cycle apparatus is a refrigeration cycle apparatus having a refrigerant circuit having a compressor, a condenser, a supercooler, an expansion device, and an evaporator connected by a refrigerant pipe, and configured to circulate refrigerant containing refrigerant having a temperature gradient, wherein the supercooler sets a degree of supercooling of the refrigerant, which is a temperature difference between a temperature from the condenser to a refrigerant flow inlet of the supercooler and a temperature in a refrigerant flow outlet on a downstream side of the supercooler, to be larger than the temperature gradient generated at a time of refrigerant shortage of the refrigerant between the refrigerant flow inlet and the refrigerant flow outlet of the supercooler, the refrigeration cycle apparatus including a refrigerant amount determination unit configured to compare a determination threshold value set to a value larger than the temperature gradient of the refrigerant with the degree of supercoo

Abstract: 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.

Abstract: A fuel cell system includes a fuel cell, a first temperature sensor configured to acquire a first temperature that is a temperature of the fuel cell, a plurality of accessories that is used to operate the fuel cell, a second temperature sensor configured to acquire a second temperature that is a temperature of at least any one of the plurality of accessories, and a controller configured to perform control on the plurality of accessories to execute a warming-up operation of the fuel cell. The controller is configured to execute the warming-up operation when any of a first condition that the first temperature is lower than a predetermined first threshold temperature and a second condition that the first temperature is equal to or higher than the first threshold temperature and the second temperature is lower than a predetermined second threshold temperature is satisfied.

Abstract: A fuel cell system includes: a plurality of fuel cell units of which each includes a fuel cell, an air supply pipe, an air supply device, an air discharge pipe, and a control unit; and an exhaust pipe connected to the plurality of air discharge pipes and configured to discharge exhaust gas to the outside of the fuel cell system. The control units of the plurality of fuel cell units are configured such that, when one or more fuel cell units included in the plurality of fuel cell units are operating to generate electric power and each of the remainder of the plurality of fuel cell units is not operating to generate electric power, the control unit of the fuel cell unit that is not operating to generate electric power activates the air supply device of the corresponding fuel cell unit.

Abstract: A fuel cell system includes a fuel cell, an anode gas supply system, an anode gas circulatory system, a cathode gas supply-discharge system, a gas-liquid discharge passage, a gas-liquid discharge valve configured to open and close the gas-liquid discharge passage, a flow-rate acquisition portion, and a controlling portion. After the controlling portion instructs the gas-liquid discharge valve to be opened, the controlling portion executes a normal-abnormality determination such that, when a discharge-gas flow rate of anode gas is a predetermined normal reference value or more, the controlling portion determines that the gas-liquid discharge valve is opened normally, and when the discharge-gas flow rate is lower than the normal reference value, the controlling portion determines that the gas-liquid discharge valve is not opened normally.

Abstract: A fuel cell system includes fuel cell units each including a fuel cell stack, an anode gas discharge system configured to discharge anode gas from the fuel cell stack, and a cathode gas supply and discharge system configured to supply cathode gas to the fuel cell stack and discharge cathode gas from the fuel cell stack, a mixed gas discharge system configured to mix gas discharged from the anode gas discharge system and the cathode gas supply and discharge system of each fuel cell unit and discharge the mixed gas, and a controller configured to control the fuel cell units. The controller is configured to control at least one of the anode gas discharge system and the cathode gas supply and discharge system of each fuel cell unit to shift a time at which gas to be discharged from each fuel cell unit merges in the mixed gas discharge system.

Abstract: A fuel cell system wherein the controller preliminarily stores a data group indicating a correlation between a voltage of the fuel cell and a concentration of impurity gas in the fuel gas; wherein the controller controls ON and OFF of the fuel gas supplier, wherein the controller operates the fuel gas supplier and determines whether or not the fuel cell voltage measured by the voltage sensor after an elapse of a predetermined time is less than a first threshold; and wherein, when the controller determines that the fuel cell voltage measured by the voltage sensor is less than the first threshold, the controller compares the voltage with the data group and determines that the concentration of the impurity gas in the fuel gas is higher than a predetermined concentration threshold.

Abstract: To provide a fuel cell system configured to, when fuel cell stacks are installed in a vehicle and an impurity is contained in fuel gas, minimize the number of fuel cell stacks to which the fuel gas containing the impurity is supplied. A fuel cell system wherein, after power generation by a first stack, a controller determines whether or not an impurity is contained in a fuel gas filled into a fuel tank; wherein, when the controller determines that an impurity is contained in the fuel gas filled into the fuel tank, the controller determines whether or not the impurity is a poisoning substance; and wherein, when the controller determines that the impurity is the poisoning substance, the controller prohibits the supply of the fuel gas to fuel cell stack(s) other than the first stack.

Abstract: 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.

Abstract: A fuel cell system includes a fuel cell a temperature acquisition unit that acquires a temperature of the fuel cell, a cell unit voltage sensor that detects a voltage of each of fuel cell units, and a controller that controls the fuel cell system. The controller restricts an output current of the fuel cell when the voltage of the individual fuel cell unit becomes equal to or lower than a predetermined value in a warm-up operation, execute the warm-up operation when the temperature of the fuel cell is equal to or lower than a predetermined temperature, after the fuel cell system receives a start-up request, and stop an operation of the fuel cell system when a stop condition including that the voltage of the fuel cell unit is continuously equal to or lower than a predetermined voltage value for a predetermined time is satisfied after start of the warm-up operation.

Abstract: A fuel cell system includes a plurality of fuel cell units each including a fuel cell, a fuel cell cooling system having a heat exchanger that exchanges heat between a primary-side coolant, and a secondary-side coolant flowing through the fuel cell, and a coolant pump that adjusts the flow rate of the secondary-side coolant, and a controller that controls the fuel cell, a cooling device, and a cooling system that supplies the primary-side coolant from the cooling device to each fuel cell unit. During stop of operation of the fuel cell system, the cooling device supplies the primary-side coolant having a temperature equal to or higher than a predetermined temperature to each fuel cell unit, and the controller activates the coolant pump to cause the secondary-side coolant to flow through the heat exchanger, in one or more fuel cell units in which the fuel cell has a possibility of freezing.

Abstract: A fuel cell system herein may include a battery configured to supply electric power to a fuel cell auxiliary device used for activating a fuel cell stack. When remaining electric energy in the battery is higher than an electric energy threshold upon activation of the fuel cell stack, a controller of the fuel cell system may start outputting current from the fuel cell stack after a fuel concentration in the fuel cell stack reaches a predetermined fuel concentration threshold, and when the remaining electric energy decreases below the electric energy threshold while the fuel concentration is being increased, the controller may start outputting current from the fuel cell stack regardless of the fuel concentration in the fuel cell stack. The current can be obtained from the fuel cell stack even when the remaining electric energy in the battery is low.

Abstract: A fuel cell system includes fuel cell units each including a fuel cell stack, an anode gas discharge system configured to discharge anode gas from the fuel cell stack, and a cathode gas supply and discharge system configured to supply cathode gas to the fuel cell stack and discharge cathode gas from the fuel cell stack, a mixed gas discharge system configured to mix gas discharged from the anode gas discharge system and the cathode gas supply and discharge system of each fuel cell unit and discharge the mixed gas, and a controller configured to control the fuel cell units. The controller is configured to control at least one of the anode gas discharge system and the cathode gas supply and discharge system of each fuel cell unit to shift a time at which gas to be discharged from each fuel cell unit merges in the mixed gas discharge system.

Abstract: An FC (fuel cell) system includes: an FC; a radiator configured to cool a CL (cooling liquid); an ion exchanger provided in a BFP (bypass flow path) branched off from a CFP (circulation flow path) for allowing the CL to circulate between the FC and the radiator; a multi-way valve provided in a branching point at which the BFP is branched off from the CFP; and a pump which circulates the CL. A percentage of the CL that is made to flow through the BFP can be controlled by the multi-way valve. In a case in which a stop time is longer than a threshold time when the FC system is started up, after the CL is circulated through the radiator, the CL is circulated through the BFP at the percentage of 80% or more until electrical conductivity of the CL becomes smaller than a threshold electrical conductivity.

Abstract: A fuel cell system includes: a plurality of fuel cell units of which each includes a fuel cell, an air supply pipe, an air supply device, an air discharge pipe, and a control unit; and an exhaust pipe connected to the plurality of air discharge pipes and configured to discharge exhaust gas to the outside of the fuel cell system. The control units of the plurality of fuel cell units are configured such that, when one or more fuel cell units included in the plurality of fuel cell units are operating to generate electric power and each of the remainder of the plurality of fuel cell units is not operating to generate electric power, the control unit of the fuel cell unit that is not operating to generate electric power activates the air supply device of the corresponding fuel cell unit.

Abstract: A fuel cell system includes: a fuel cell generating electricity when being supplied with anode gas and cathode gas; a supply channel through which the anode gas to be supplied to the fuel cell flows; a discharge channel through which anode-off gas discharged from the fuel cell flows; a discharge valve provided on the discharge channel and opened to discharge the anode-off gas; and a control section controlling opening/closing of the discharge valve. The control section calculates a valve open time of the discharge valve corresponding to a target value of a discharge amount of the anode-off gas by using an aperture ratio of the discharge channel and the target value, and closes the discharge valve based on the valve open time, the aperture ratio of the discharge channel being calculated from a first discharge amount of the anode-off gas, which is discharged by opening of the discharge valve.