Nissan Motor Company Limited

Yasuyuki Itou

Kouji Ishihara

Takashi Fukuda

Hiroshi Miyakubo

Toshihiro Takekawa

Hidetoshi Itou

An electric motor () and an accessory circuit () are connected in parallel to an output terminal (A) of a fuel cell power plant (). A secondary battery () is connected to the output terminal (A) through a DC/DC converter () which controls an output voltage in both directions. The accessories () are directly driven by the output of the fuel cell power plant (). A reduction in the output voltage of the fuel cell power plant () resulting from an increase in the load of the electric motor () is prevented by discharging power from the secondary battery () via the DC/DC converter (). By directly supplying electric current output from the fuel cell plant to the accessory circuit () without passing through the DC/DC converter (), the power loss due to the DC/DC converter () is reduced.

Power source device for electric motor

A compressor which adjusts the pressure of an oxygen-containing gas supplied to a fuel cell system, a throttle valve which controls the flowpath surface area of part of the oxygen-containing gas, and shutoff valves which divide the oxygen-containing gas downstream of the compressor between a fuel cell and reformer, are provided. When fuel vapor absorbed by the canister is purged, the opening of the throttle valve is reduced, and the canister is made to communicate with the upstream side of the compressor. Due to the negative pressure upstream of the compressor, fuel vapor absorbed by the canister is divided between the reformer or a burner, and processed.

Fuel cell system

A fuel cell system is provided with a fuel cell, a fuel gas supply line supplying fuel gas to the fuel cell, an oxidizing gas supply line supplying oxidizing gas to the fuel cell, a circulation line circulating fluid through at least one of the fuel cell, the fuel gas supply line and the oxidizing gas supply line, and a microorganism inhibiting unit located in the circulation line to execute sterilization so as to sterilize microorganisms present in the fluid. The microorganism inhibiting method is utilized in the fuel cell system of such a structure to sterilize the microorganisms present in the fluid in the midway of the circulation line.

Fuel cell system and microorganism inhibiting method

A fuel cell vehicle comprises a fuel cell system ( ), a fuel tank ( ) which stores fuel supplied to the fuel cell system ( ), and a sensor ( ) which detects a remaining fuel amount in the fuel tank ( ). A controller ( ) of the fuel cell system ( ) predicts a possible running distance of the vehicle based on an energy amount obtained by subtracting the energy required to start the fuel cell system ( ) from the energy amount corresponding to the detected remaining fuel amount.

Fuel cell vehicle and method for predicting possible running distance

In a cylinder injection spark-ignition engine having a spark plug to ignite an air mixture fuel within a corresponding cylinder; a fuel injector to inject fuel into a combustion chamber; a catalytic converter interposed in an exhaust passage; and a controller, the controller being programmed to: command the fuel injector to inject a main fuel into the combustion chamber for a first time duration within at least one of a suction stroke and a compression stroke and to inject an additional fuel for a second time duration within at least one of an expansion stroke and an exhaust stroke, the controller is programmed to set a target value of a total air-fuel mixture ratio to a value of the air-fuel mixture ratio which is leaner than a stoichiometric air-fuel mixture ratio for a warm-up condition of the catalytic converter and the controller is programmed to calculate respective injection quantities (Ti and Ti ) of the main fuel and the additional fuel in such a manner that the total air-fuel mixture ratio based on a sum of the main fuel and the additional fuel corresponds to the set target value of the total air-fuel mixture ratio.

Cylinder direct injection spark-ignition internal combustion engine

A system and method for diagnosing deterioration of a nitrogen oxide (NOx) catalyst for an internal combustion engine. An output signal indicative of concentration of nitrogen oxides (NOx) in exhaust gas passing through the NOx catalyst is generated from a NOx sensor. Rates of change in the detected NOx concentration are calculated a plurality of times over a predetermined period of time after an air/fuel ratio becomes less than a stoichiometric air/fuel ratio. A representative value derived from the calculated rates of change in the detected NOx concentration is compared with a predetermined reference value for determining that the NOx catalyst is deteriorated.

Method and system for diagnosing deterioration of NOx catalyst

A deterioration diagnosing system for a NOx-occluded catalyst comprises an inlet NOx concentration estimating unit which estimates NOx concentration at an inlet part of the catalyst; an outlet NOx concentration detecting unit which detects NOx concentration at an outlet part of the catalyst; and a deterioration degree judging unit which judges a deterioration degree of the catalyst in accordance with a rate of the minimum value of NOx concentration detected by the detecting unit for a predetermined period to a value of NOx concentration estimated by the estimating unit at the time when the minimum value of NOx concentration is detected. The predetermined period is a period between a time when the engine exhaust gas shows the stoichiometric and/or richer air/fuel ratio and a subsequent time when the engine exhaust gas shows the stoichiometric and/or richer air/fuel ratio.

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Yokohama, Japan

Yasuyuki Itou