Toto Ltd.

Katsuhisa Tsuchiya

Toshiharu Ooe

Tsukasa Shigezumi

Kiyotaka Nakano

Toshiharu Otsuka

Takuya Matsuo

Yoshiyuki Kawamura

Yousuke Akagi

Naoki Watanabe

Shoichi Tsuiki

Masami Tsujita

Hiroshi Tsuboi

Kensuke Murata

Masayuki Nagaishi

Toshiya Abe

Shuhei Tanaka

Takuya Hoshiko

Koji Omoshiki

Megumi Shimazu

Chihiro Kobayashi

Tomoyuki Abe

Mitsunobu Shiono

Naoki Kabe

Hajime Omura

To provide a solid oxide fuel cell system capable of avoiding the reduction of air electrodes. The present invention is a solid oxide fuel cell system including: a fuel cell module, a fuel supply apparatus, a water supply apparatus, an oxidant gas supply apparatus, a reformer, and a control section for controlling the extraction of power, whereby the controller having a shutdown stop circuit for executing a shutdown stop when the fuel cell stack is above the predetermined temperature, and after a shutdown stop, during a period when pressure on the fuel electrode side is sufficiently higher than pressure on the air electrode side, and no reverse flow of oxidant gas to the fuel electrode side is occurring, a temperature drop operation is executed whereby high temperature oxidant gas remaining on the oxidant gas electrode side is discharged.

Solid oxide fuel cell system

To provide a fuel cell device capable of extending the years of service life of a reformer by suppressing thermal runaways. The present invention is a solid oxide fuel cell device, including a fuel cell module having fuel cell units; a reformer disposed above the fuel cell units, for producing hydrogen by a partial oxidation reforming reaction and a steam reforming reaction; a vaporizing chamber disposed adjacent to the reformer; a combustion chamber for heating the vaporization chamber; a water supply device; an electrical generation oxidant gas supply device; and a controller for raising the fuel cell units to a temperature at which electrical generation is possible; whereby over the entire period of the startup step, the reforming oxidant gas supply device and water supply device are controlled so that partial oxidation reforming reactions do not occur independently in the reformer.

Solid oxide fuel cell device

The present invention provides a solid oxide fuel cell system capable of preventing excess temperature rises while increasing overall energy efficiency. The present invention is a solid oxide fuel cell system, including: a fuel cell module, a fuel supply device, a heat storing material, and a controller which, based on power demand, increases the fuel utilization rate when output power is high and to lower it when output power is low, and changes the electrical power actually output at a delay after changing the fuel supply amount. The controller has a stored heat estimating circuit for estimating the surplus heat based on fuel supply and on power output at a delay relative thereto. When a utilizable amount of surplus heat is accumulated in the heat storage material, the fuel supply is reduced so that the fuel utilization rate increases relative to the same electrical power.

Solid oxide fuel cell system for producing variable generated power based on power demand

The present invention is to provide a solid oxide fuel cell capable of improving the overall energy efficiency. The present invention is directed to a solid oxide fuel cell and comprising: a fuel cell module; a fuel supply device; a combustion chamber for burning excess fuel and heating; a heat storing material, a power demand detecting sensor; a temperature detection device, and a control device for controlling so that the fuel utilization rate is high when generated power is large, and also for changing output power at a delay to the fuel supply rate; whereby the control device comprises a stored heat amount estimating circuit, and when it is estimated that a utilizable heat amount has accumulated in the heat storing material, the fuel supply rate is reduced so that the fuel utilization rate increases vs. the same generated power.

The invention is to provide a solid oxide fuel cell system including: a fuel cell module, a fuel flow regulator unit, a first power demand detection device, a control section for controlling a fuel supply amount and setting the current value extractable from the fuel cell module, an inverter for extracting current in a range not exceeding the extractable current value, and a power state detecting sensor for detecting actual extracted current value; whereby if actual extracted current value declines, then under circumstances where power demand begins to rise in a state of extra margin in the fuel supply amount after the controller suddenly decreases the extractable current value and suddenly reduces the electrical collector, the controller increases the extractable current value at a high current rise rate of change.

To provide a fuel cell system with which degradation of fuel cells can be suppressed by avoiding the ill effects caused by bumping of water used for steam reforming during the electrical generation. The present invention is a solid oxide fuel cell system including: a fuel cell module, a fuel flow regulator unit, a reformer for reforming supplied fuel, a vaporizing section for supplying steam to the reformer, a water flow regulator unit, and a controller for controlling the fuel supply device and water supply device, and for controlling the power extracted from the fuel cell module; whereby the controller is furnished with: a bumping determination circuit for determining the occurrence of excessive vaporization of water in a vaporizing chamber, and an extracted power limiting circuit for limiting the power when the bumping determination circuit has determined excessive bumping of water.

Solid oxide fuel cell system responsive to explosive vaporization of water in reformer to control power

A solid oxide fuel cell system is disclosed. The solid oxide fuel cell system includes a cell stack having multiple adjacent fuel cells; a reformer that reforms raw gas and produces fuel gas supplied to the fuel cells; a combustion section that causes combustion of the fuel gas discharged from the fuel cells and heats the reformer with combustion heat of the fuel gas; an ignition device that ignites the combustion section; a combustion state confirmation device that senses that heating of the entire reformer has started using the advancement of flame transfer between fuel cells in the combustion section; and a controller programmed to start an operation of the system heating the reformer by using combustion heat from the combustion section and reaction heat from the partial oxidation reforming reaction (POX) in the reformer. During the period until the combustion state confirmation device senses that the heating of the entire reformer has started after the ignition device ignited the combustion section, the controller suppresses the amount of heat emitted by the partial oxidation reforming reaction in the reformer more than the amount of heat emitted after heating of the entire reformer has started.

To provide a solid oxide fuel cell system capable of efficiently and simply controlling a low speed fuel cell module and a high speed inverter. The invention is a solid oxide fuel cell system, comprising: a fuel cell module, a fuel flow regulator unit, a control section comprising a first power demand detection circuit for controlling the fuel supply amount and for setting the value of current extractable from the fuel cell module; an inverter for extracting current from fuel cell module; and a second power demand detection circuit; and having an inverter control section for controlling the inverter independently from the fuel cell controller so that a current responsive to power demand is extracted from the fuel cell module in a range not exceeding the extractable current value input from the fuel cell controller.

To provide a fuel cell device capable of extending the years of service life of a reformer by suppressing thermal runaways. The present invention is a solid oxide fuel cell device, including a fuel cell module having multiple fuel cell units; a reformer disposed above the fuel cell units, for producing hydrogen by a partial oxidation reforming reaction and a steam reforming reaction; a vaporizing chamber disposed adjacent to the reformer; a combustion chamber for heating the vaporization chamber; a water supply device; a supply device for oxidant gas for electrical generation; and a controller for raising the fuel cell unit to a temperature at which electrical generation is possible; wherein fuel electrodes in each individual fuel cell unit are constituted to act as catalysts for a shift reaction, and the controller executes only the ATR step and SR step in the reformer.

To provide a solid oxide fuel cell device capable of smooth transition from a startup state to an electrical generating state. The present invention is a solid oxide fuel cell device () for generating electricity, having a fuel cell module (); a reformer (), a fuel supply device (); a water supply device (), a generating oxidant gas supply device (), and a controller () for controlling the fuel supply device and water supply device at the time of startup when the fuel cell module solid oxide fuel cell unit is raised to a temperature at which electrical generation is possible; whereby the controller controls the fuel supply device during the SR operation such that electrical generation is started after reducing the fuel supply flow rate prior to starting electrical generation.

To provide a solid oxide fuel cell system with which the durable lifespan of the reformer can be extended by suppressing temperature unevenness in the reformer. The present invention is a solid oxide fuel cell, including a fuel cell module, a reformer for producing hydrogen by POX, ATR, and SR steps; a fuel supply apparatus, a reform air supply apparatus, a water supply apparatus, a generating air supply apparatus, and a control device which, as the temperature inside the fuel cell module rises, executes in sequence POX, ATR and SR steps at predetermined respective temperature bands, and causes a rise in temperature at which electrical generation is possible; wherein the control device comprises a localized temperature rise suppression circuit which, by causing steam reforming to occur locally within the reformer in the POX step, suppresses localized temperature rises in the reformer.

A solid oxide fuel cell device is provided which prevents excessive rising of the temperature inside a fuel cell module during the startup process. In a startup process, control unit controls to cause a transition from a fuel gas reforming reaction process to a POX process, an ATR process, and a SR process, then to a generating process; when the cell stack temperature and reformer temperature in each process satisfy respectively set transition conditions, a transition to the next process takes place; if control unit determines a temperature rise assist state exists, it executes an excess temperature rise suppression control so that during at least the transition to the generating process, the reformer temperature does not exceed a predetermined value.

To provide a solid oxide fuel cell device for preventing excess temperature rises inside a fuel cell module during the startup process. During a startup process, a control unit controls the supplied amounts of fuel gas, oxidant gas, and steam supplied to a reformer based on cell stack temperature and reformer temperature and causes transition to a generating process after transitioning to a POX process, an ATR process, and a SR process, and controls to cause a transition to the next process if in each process the cell stack temperature and reformer temperature meet transition conditions set for each; when control unit determines a temperature rise assist state, it controls to cause a transition to the generating process in a state of reduced fuel gas supply amounts compared to when it does not determine a temperature rise assist state.

The SOFC of the present invention has a plurality of individual solid oxide fuel cells () disposed within an generating chamber (), a fuel supply unit () for supplying fuel to the individual solid oxide fuel cells, a temperature sensor () for measuring the temperature of the generating chamber (T), and a control section () for changing the amount of fuel supplied in response to an amount of generation required based on control characteristics for supplying fuel, wherein the control section is furnished with a temperature band for monitoring purposes, having a minimum temperature value (Ta) and a maximum temperature value (Tb) for adaptive control, predetermined based on a minimum amount and maximum amount of rated electrical generation, and a maximum temperature value for adaptive control in response to anomalies, which is higher than the maximum temperature value (Tb) of the adaptive control temperature band, and a minimum temperature value for adaptive control in response to anomalies, which is lower than the minimum temperature value (Ta) of the adaptive control temperature band, and the control section is furnished with: an anomaly response control section for executing anomaly response control by restricting operation of the fuel cell when the generating chamber temperature (T) is higher than the maximum temperature value for anomaly response control or lower than the minimum temperature value for anomaly response control, and with an adaptive control section for executing adaptive control by correcting the amount of fuel supplied based on a temperature signal from the temperature measurement sensor so that the generating chamber temperature (T) is kept within the temperature band when the generating chamber temperature (T) exceeds the minimum temperature value (Ta) or maximum temperature (Tb) for adaptive control and goes outside the temperature band.

A solid oxide fuel cell is provided with which the further advance of degradation can be restrained relative to fuel cell units in which degradation has advanced. The present invention is a solid oxide fuel cell system which varies output power in response to a required generation amount. The system comprises a fuel cell module furnished with multiple fuel cell units, a fuel supply device for supplying fuel to the fuel cell module, an oxidant gas supply device for supplying oxidant gas to the fuel cell module, and a controller for changing the amount of fuel supplied from the fuel supply means in response to the required generation amount. The controller reduces the rate of change in the fuel supply amount per unit time when the required generation amount changes subsequent to an estimate or determination that the fuel cell module has degraded.

Growing community of inventors

Kitakyushu, Japan

Katsuhisa Tsuchiya