A cogeneration fuel cell system and associated methods of operation are provided that accommodate a demand for heat as well as a demand for electric power The system is operated among various modes to balance heat and power demand signals In general, a fuel cell system is coupled to a power sink and a heat sink, and a controller is adapted to respond to data signals from the power sink and the heat sink As examples, such data signals from the heat sink may include a temperature indication or a heat demand signal (such as from a thermostat), and such data signals from the power sink may include a voltage or current measurement, an electrical power demand signal, or an electrical load

Method and apparatus for controlling a combined heat and power fuel cell system

A hybrid fuel cell system in which a fuel cell (2) and a heat engine (3) are employed. Waste heat from the fuel cell is used to fire the heat engine cycle and the system is configured such that a high temperature fuel cell and conventional heat exchange equipment can be used in the system. Additionally, the configuration allows independent operation of the fuel cell (2) and the heat engine (3).

High-efficiency fuel cell system

A fuel cell system includes an ECU that sets the fuel cell stack to a state of idling stop by lowering both a revolution speed of an air pump and a discharge current value of the fuel cell stack to less than during idling power generation within a range larger than 0, in response to a predetermined idling stop initiation condition having been satisfied during idling power generation. The ECU decreases the discharge current value further as the lowest cell voltage value CV_low of the fuel cell stack decreases so that the lowest cell voltage value CV_low does not fall below a cancellation threshold B, with an event of the lowest cell voltage CV_low of the fuel cell stack having fallen below the cancellation threshold B as a cancellation condition of idling stop.

Fuel cell system and control method thereof

PROBLEM TO BE SOLVED: To solve a problem that if a high voltage battery is fully charged when a vehicle is driven saving energy, regenerative electric power cannot be used effectively.SOLUTION: A control device 4 for the vehicle has the high voltage battery 11, a vehicle-mounted electric device operated upon receiving supply of electric power from the high voltage battery 11, and an eco-switch 21 for reducing power consumption of the vehicle-mounted electric device, and the control device 4, if power accumulating capacity SOC of the high voltage battery 11 becomes larger than a first threshold when the power consumption of the vehicle-mounted electric device in operation is reduced, stops reduction of power consumption of the vehicle-mounted electric device in operation.

Power conversion apparatus

The present invention relates to a fuel cell vehicle capable of efficiently cooling a fuel stack and supplying sufficient reactant gas to the fuel stack with only a single air supply means.

Fuel cell vehicle

A control device for a fuel cell including a transient state determination unit which determines whether changes in generated output of the fuel cell are within a predetermined range; a hydrogen purge detection unit which detects the presence/absence of a purge command to a hydrogen purge valve; a failure determination unit which determines, if the transient state determination unit determined that it is not a transient state, failure in the hydrogen purge valve based on an actual hydrogen pressure value at an inlet portion of the fuel cell and a target hydrogen pressure value, which is set in accordance with the presence/absence of the purge command detected by the hydrogen purge detection unit; and an alarm unit which generates an alarm when failure in the hydrogen purge valve is determined by the failure determination unit.

Control device for fuel cell

A hydrogen purge control apparatus includes a fuel cell stack from which hydrogen is purged as necessary, a purged hydrogen dilution device which is disposed downstream of the fuel cell stack, and which has a chamber formed therein, a first inlet for purged hydrogen, a second inlet for air, and an outlet for diluted hydrogen, a regulator which is disposed between the fuel cell stack and the first inlet, and which is provided for regulating an amount of the purged hydrogen flowing into the purged hydrogen dilution device, and a control unit having a hydrogen concentration estimating section that is configured to estimate the hydrogen concentration at the outlet of the purged hydrogen dilution device based on an operating state of the fuel cell stack. The regulator is operated by the control unit depending on the hydrogen concentration estimated by the hydrogen concentration estimating section.

Hydrogen purge control apparatus

A start-up method for a fuel cell system that includes a fuel cell that carries out power generation by the electrochemical reaction between a fuel gas and the oxygen gas in the air; a fuel gas discharge path and a fuel gas supply path that are connected to the fuel cell; a fuel gas circulation path in which the fuel gas discharge path merges with the fuel gas supply path; and a purge valve provided on the fuel gas circulation path in order to discharge the circulating fuel gas from the fuel gas circulation path. The method includes the steps of opening the purge valve at the same time that the fuel gas is supplied to the fuel cell and replacing the nitrogen gas that originates in the air and is present in the fuel gas circulation path by fuel gas; and closing the purge valve after the nitrogen gas in the fuel gas circulation path has been replaced by the fuel gas.

Start-up method for fuel cell

A control system for a fuel cell includes a vapor generation unit, a fuel reforming unit, a fuel supply unit, a combustion unit, a fuel vapor temperature detection unit, a temperature detection unit, a current detection unit, and a control unit. The vapor generation unit produces a fuel vapor by vaporizing a liquid fuel. The fuel reforming unit reforms the fuel vapor to produce a hydrogen-enriched fuel. The fuel supply unit supplies the reformed fuel to the fuel cell. The control unit calculates quantity of heat retained by the vapor generation unit based on the temperature of the fuel vapor, the temperature of the combustion unit, and the generated current. The control unit also controls a fuel supply command value for the fuel supply unit and/or a current generation command value for the fuel cell based on the calculated quantity of heat retained by the vapor generation unit.

Control system for fuel cell

PROBLEM TO BE SOLVED: To control pressure flow rate characteristics of a fuel supplied to a fuel cell with sufficient accuracy. SOLUTION: A control equipment 10 of a fuel cell is constituted with a fuel cell 11, a fuel supply section 12, a steam generating section 13, a combustion section 14, a reforming section 15, a CO reduction section 16, an oxidizer supply section 17, a control section 18, a discharge fuel flow rate control section 19, a reforming fuel pressure detecting device 21, a reforming fuel flow rate detecting device 22, a discharge fuel pressure detecting device 23, and a power generation current detecting device 24. The discharge fuel flow rate control section 19 is composed of a plurality of for example, two small flow rate bulbs 27 and a large flow rate bulb 28 with different pressure flow-rate characteristics arranged in parallel. A signal from the reforming fuel pressure detecting element 21 which detects a pressure P1 of the reforming fuel, a signal from the reforming fuel flow rate detecting element 22 which detects a flow rate Q of the reforming fuel, a signal from the discharge fuel pressure detecting element 23 which detects a pressure P2 of the discharge fuel, and a signal from the power generation current detecting element 24 which detects power generation current 1 are inputted into the control section 18. COPYRIGHT: (C)2001,JPO

Kenichiro Ueda

Papers

Control device for fuel cell

Hydrogen purge control apparatus

Start-up method for fuel cell

Control system for fuel cell

Controller for fuel cell