Abstract: A hydrogen concentration calculating process calculates a hydrogen concentration in a specific portion of a target region based on an operating state of an internal combustion engine. The internal combustion engine uses hydrogen as fuel. A downstream passage is a portion of an intake passage of the internal combustion engine that is downstream of a throttle valve. A connecting passage connects a crank chamber of the internal combustion engine to the downstream passage. The target region is a region including the crank chamber and the connecting passage. When a condition is met, in which the hydrogen concentration is greater than or equal to a predetermined determination value, a pressure reduction process causes a pressure in the downstream passage to be lower than that at a point in time when the condition is met.

Abstract: A controller for an engine includes processing circuitry. The processing circuitry executes an obtaining process that obtains a catalyst temperature, which is a temperature of a catalyst. The processing circuitry executes a setting process that sets a target air-fuel ratio that is a target value of an air-fuel ratio in the cylinder. The temperature of the catalyst at which an efficiency of nitrogen oxide reduction by the catalyst is the highest is referred to as a prescribed temperature. In the setting process, the processing circuitry sets the target air-fuel ratio to be higher when the catalyst temperature is a first value that is lower than the prescribed temperature, than when the catalyst temperature is a second value that is lower than or equal to the prescribed temperature and higher than the first value.

Abstract: A controller for an engine includes processing circuitry. The processing circuitry executes an obtaining process that obtains a catalyst temperature, which is a temperature of a catalyst. The processing circuitry executes a setting process that sets a target air-fuel ratio that is a target value of an air-fuel ratio in the cylinder. The temperature of the catalyst at which an efficiency of nitrogen oxide reduction by the catalyst is the highest is referred to as a prescribed temperature. In the setting process, the processing circuitry sets the target air-fuel ratio to be higher when the catalyst temperature is a first value that is lower than the prescribed temperature, than when the catalyst temperature is a second value that is lower than or equal to the prescribed temperature and higher than the first value.

Abstract: A first pressure sensor is disposed in a first fuel system between a first shutoff valve and a second shutoff valve. A second pressure sensor is disposed in a second fuel system between the second shutoff valve and a fuel injection valve. A determination process determines a leakage anomaly in the first fuel system or the second fuel system based on a first magnitude relationship or a second magnitude relationship. The first magnitude relationship is a relationship between a detection value of the first pressure sensor in a state in which the first fuel system is filled with gaseous fuel and a first threshold value. The second magnitude relationship is a relationship between a detection value of the second pressure sensor in a state in which the second fuel system is filled with gaseous fuel and a second threshold value.

Abstract: A controller for a hydrogen engine is provided. Control circuitry performs, after a stop request for the hydrogen engine, a water reduction process that reduces a proportion of water vapor in exhaust gas. The control circuitry stops the hydrogen engine after operating the hydrogen engine with the water reduction process executed.

Abstract: A controller for a hydrogen engine is provided. Control circuitry performs, after a stop request for the hydrogen engine, a water reduction process that reduces a proportion of water vapor in exhaust gas. The control circuitry stops the hydrogen engine after operating the hydrogen engine with the water reduction process executed.

Abstract: A vehicle including an internal combustion engine and an automatic transmission capable of transmitting and receiving torque to and from an output shaft of the internal combustion engine is controlled. During operation of the internal combustion engine, a process that calculates a diluted water amount based on an operation state of the internal combustion engine is executed. The diluted water amount is the amount of water contained in lubricating oil in the internal combustion engine. Further, a process that controls the automatic transmission such that torque per unit period in the internal combustion engine becomes smaller when the diluted water amount is relatively large compared to when the diluted water amount is relatively small, while continuing the operation of the internal combustion engine, is executed.

Abstract: A hydrogen concentration calculating process calculates a hydrogen concentration in a specific portion of a target region based on an operating state of an internal combustion engine. The internal combustion engine uses hydrogen as fuel. A downstream passage is a portion of an intake passage of the internal combustion engine that is downstream of a throttle valve. A connecting passage connects a crank chamber of the internal combustion engine to the downstream passage. The target region is a region including the crank chamber and the connecting passage. When a condition is met, in which the hydrogen concentration is greater than or equal to a predetermined determination value, a pressure reduction process causes a pressure in the downstream passage to be lower than that at a point in time when the condition is met.

Abstract: An electric railcar power feeding system in an embodiment includes a power storage device, a rectifier, and an emergency power supply. The power storage device is connected to a feeder line for an electric railcar. The rectifier converts alternating-current power of a first power system to direct-current power and supply the direct-current power for the feeder line. The emergency power supply supplies power of a second power system different from the first power system for the feeder line.

Abstract: An electric railcar power feeding system in an embodiment includes a power storage device, a rectifier, and an emergency power supply. The power storage device is connected to a feeder line for an electric railcar. The rectifier converts alternating-current power of a first power system to direct-current power and supply the direct-current power for the feeder line. The emergency power supply supplies power of a second power system different from the first power system for the feeder line.