Nissan Motor Company Limited

Masaru Okamoto

Katsunori Oshiage

Kazuo Saito

Taketoshi Kawabe

Yoshinori Yamamura

Masatoshi Iio

A fuel cell system has a fuel cell generating power using a fuel gas and an oxidizing agent gas serving as materials of the system and a material supply section supplying the materials to the fuel cell. The power generated by the fuel cell is extracted to a load. A device for controlling the fuel cell system has: a material flow calculation section calculating a material flow supplied to the fuel cell so as to cause the fuel cell to generate the power of a required power generation amount; a material reduction limit detection section calculating a limit for reducing the material flow, based on a power generation state of the fuel cell; and a material flow change section controlling the material supply section so as to change the material flow calculated by the material flow calculation section to the limit calculated by the material reduction limit detection section.

Device and method for controlling fuel cell system having oxygen concentration transient reduction

Device and method for controlling fuel cell system with vibration amplitude detection

A fuel cell system and a related operating method are disclosed. The system includes a fuel cell bodyhaving an anode electrode supplied with fuel gas containing hydrogen and a cathode electrode supplied with oxidizer gas, a catalyst degradation-suppressing means operative to interrupt supplying oxidizer gas to the cathode electrode after disconnecting the external load from the fuel cell bodyand allow a load current, generated by the fuel cell body, to be extracted by an internal loadwhile supplying fuel gas to the anode electrode, a hydrogen supply stop means operative to interrupt a supply of fuel gas to the anode electrode during a period in which the load current is extracted by the internal load, and load current control means controlling a target load current such that after the supply of fuel gas to the anode electrode is stopped, a pressure inside the anode electrode is maintained at a target pressure.

Fuel cell system

A fuel cell system comprises a reformer () which produces reformate gas containing hydrogen using gas containing oxygen and raw material vapor, and a fuel cell () which generates power by reacting hydrogen in the reformate gas with oxygen. A controller () determines whether or not excess hydrogen has been produced by the reformer (), and when it is determined that excess hydrogen was produced, burns the excess hydrogen to keep the reformer () warm.

Fuel cell system having reformer temperature maintenance system and control method thereof

A control device for a fuel cell system has a fuel cell body, a fuel gas supply system supplying fuel gas to the fuel cell body in dependence on a demanded power output of the fuel cell body; an air supply system supplying air to the fuel cell body in dependence on the demanded power output, a combustor combusting exhaust gases exhausted from the fuel cell body, a temperature sensor sensing a temperature of the combustor, a discriminator section discriminating whether an increase in the temperature as sensed is equal to or above a predetermined threshold value when the demanded power output increases, and a permitting section permitting the power output available from the fuel cell body to be increased when the discriminator section discriminates that the increase in the temperature as sensed is equal to or above the predetermined threshold value.

Control device for fuel cell system and control method

A fuel cell system is provided which controls the temperature while maintaining the internal pressure of the fuel cell system to a permitted pressure range. A target variation amount in the flow rate of the anode effluent is calculated based on a single target temperature-time curve selected from a plurality of target temperature-time curves. Furthermore the pressure variation of the reformate gas produced by variation in the target flow rate is predicted. It is determined whether the predicted pressure will be maintained to a permitted temperature range. When the predicted pressure will not be maintained to the permitted temperature range, a temperature-time curve with more gentle variation is selected. A final curve is selected by repeating the selection process until it is determined that the predicted pressure will be maintained to the permitted temperature range.

A reformer ( ) generates hydrogen rich gas from vaporized methanol and a fuel cell stack ( ) generates electric power by a reaction of hydrogen rich gas. A combustor ( ) generates heat due to combustion of fuel and supplies it to a vaporizer ( ) for vaporizing liquid methanol. A controller ( ) increases a fuel supply amount to the combustor ( ) when the methanol supply amount to the vaporizer ( ) is increased. The controller also calculates a prediction temperatures of the combustor ( ) (S ) and suppresses the fuel supply amount when any one of the prediction temperature is lower than a predetermined temperature (S , S A).

Combustor temperature control of fuel cell power plant

A fuel cell stack ( ) generates power using hydrogen-rich gas obtained by reforming vaporized methanol in a reformer ( ). The vaporized methanol is generated by vaporizing liquid methanol in a vaporizer ( ). The vaporizer ( ) is heated by combustion gas from a combustor ( ). A sensor ( ) detects a liquid methanol amount supplied to the vaporizer ( ) by a methanol pump ( ). A controller ( ) calculates a prediction temperature of the vaporizer ( ) based on the liquid methanol supply amount, and limits an increase of the liquid methanol supply amount from the methanol pump ( ) so that the prediction temperature does not fall below a predetermined temperature (S A, S B). In this way, temperature drop of the vaporizer ( ) from the predetermined temperature is prevented.

Vaporizer temperature control in fuel cell power plant

A fuel cell system and a method of controlling the same, wherein the fuel cell system includes a fuel cell a reformer a combustor a combustor temperature controller that controls output temperature of the combustor at a target temperature, and a reformed gas ingredient concentration presumption unit that produces a presumed output representing ingredient concentration of reformed gas by using given parameters. The combustor temperature controller produces a parameter correction data to correct the given parameters such that the output temperature of the combustor is controlled at the target temperature in quick response to variations in the output temperature of the reformer.

Fuel cell system and method of controlling the same

A fuel cell generation system of the invention includes a reforming apparatus; a fuel cell; a reformed gas flow rate control section controlling a flow rate of reformed gas flowing from the reforming apparatus so that an operating pressure of the reforming apparatus is equal to its target pressure; a reformed gas flow rate detecting section detecting a flow rate of the reformed gas flowing into the fuel cell; a target load current calculating section calculating a target load current taken out of the fuel cell in accordance with the flow rate of the reformed gas detected by the reformed gas flow rate detecting section so that an operating pressure of the fuel cell is equal to its target pressure; an inlet pressure detecting section detecting an inlet pressure of the fuel cell; a target load current correction quantity calculating section calculating a load current correction quantity in accordance with a deviation between the inlet pressure of the fuel cell detected by the inlet pressure detecting section and the target pressure of the fuel cell; and a correction quantity adding section adding the target load current calculated by the target load current calculating section and the load current correction quantity calculated by the target load current correction quantity calculating section.

Fuel cell generation system

A braking force control system is provided with a controller connected to a vehicle operating condition detector, an engine braking force actuator and a wheel braking force actuator. The controller determines a target total braking force on the basis of the vehicle operating condition, a target transmission ratio and a target engine output on the basis of the target total braking force and calculates an engine braking force on the basis of the vehicle operating condition. The controller extracts a fast component of a rate of change of the target total braking force and determines a target wheel braking force on the basis of the fast component. The controller controls wheel braking force actuator so as to correspond the wheel braking force to the target wheel braking force. Therefore, a total responsibility of the system is improved by enhancing a follow-up characteristic during a first half of a transient period.

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Yokosuka, Japan

Masaru Okamoto