Site News  |   Monitor Keywords  |   Monitor Archive  |   Organizer  |   Account Info  |

Fuel cell system and method for operating the system

Fuel cell system and method for operating the system description/claims

The present invention relates to a fuel cell system in which a gas supply channel of a fuel cell is provided with an injector, and a method for operating the system.

At present, a fuel cell system including a fuel cell which receives supply of a reactive gas (a fuel gas and an oxidizing gas) to generate a power has been suggested and put to practical use. Such a fuel cell system is provided with a fuel supply channel for supplying, to the fuel cell, the fuel gas supplied from a fuel supply source such as a hydrogen tank.

Moreover, in general, the fuel supply channel is provided with a pressure adjustment valve (a regulator) which reduces, to a constant value, a supply pressure of the fuel gas from the fuel supply source, in a case where the supply pressure is remarkably high (e.g., see Japanese Patent Application Laid-Open No. 2004-342386).

However, in a pressure adjustment valve disclosed in Patent Document 1, a supply pressure of a fuel gas is fixed owing to a structure of the valve, so that it is difficult to quickly change the supply pressure of the fuel gas based on an operating situation (i.e., a response property is low), and such precise pressure adjustment as to change a target pressure in multiple stages cannot be performed.

Moreover, in the fuel cell system, a noise level of the whole system is remarkably low even in the operating situation, so that when an operation sound is generated in each operation device, the sound might be a harsh noise, depending on the circumstances. Therefore, there is a demand for a system in which the supply pressure of the fuel gas can appropriately be changed based on an operation state of a fuel cell and in which awareness of a noise can be suppressed.

The present invention has been developed in view of such a situation, and an object thereof is to provide a highly responsive fuel cell system in which a supply pressure of a fuel gas can appropriately be changed based on an operation state of a fuel cell and in which an operator does not easily care about an operation sound, and a method for operating the system.

To achieve the above object, a fuel cell system according to the present invention is a fuel cell system comprising: a fuel cell which receives supply of a gas to generate a power; an injector which is provided in a gas supply channel of the fuel cell and which adjusts a state of the gas on an upstream side of the gas supply channel to supply the gas to a downstream side; and control means for driving and controlling the injector, the control means being configured to control an operation of the injector based on a driving state of an associated device including the fuel cell system.

According to such a constitution, an operation state (an opening rate of a valve body of the injector (a gas passage area), and an opening time of the valve body of the injector (a gas injection time) or the like) can be set based on an operation state of the fuel cell (an amount of a power to be generated by the fuel cell (a power, a current and a voltage), a temperature of the fuel cell, an abnormal state of the fuel cell system, an abnormal state of a fuel cell main body or the like). Therefore, a gas state (a supply pressure) of a fuel gas can appropriately be changed based on the operation state of the fuel cell, so that a response property can be improved.

It is to be noted that the “gas state” is a state (a flow rate, a pressure, a temperature, a molecular concentration or the like) of the gas, and especially includes at least one of the gas flow rate and the gas pressure.

Moreover, the control means controls the operation of the injector based on the driving state of the associated device including the fuel cell system, so that the injector can be operated, for example, in a state in which an operation sound of the injector does not easily become harsh, and it can be prevented that the operation sound of the injector becomes harsh.

The associated device including the fuel cell system corresponds to, for example, a surrounding electronic device including the fuel cell system. In this case, examples of the electronic device include a pump, a motor and a fan. When the fuel cell system is mounted on a mobile body, the electronic device can be interpreted as a traction motor, an inverter, a converter or the like.

The controlling of the operation of the injector is, for example, allowing or limiting (prohibiting) of the operation of the injector, changing of a drive cycle of the injector or the like. For example, a noise frequency due to pulsation of the associated device (e.g., the pump) is matched with a drive frequency of the injector, the injector is operated at a peak of a radiant sound from the associated device, or the operation of the injector is limited (prohibited) in a case where the radiant sound from the associated device has a predetermined value or less.

In the fuel cell system, the control means may control the operation of the injector based on the radiant sound generated in accordance with the driving of the associated device.

When such a constitution is employed, for example, the operation sound of the injector is superimposed on the radiant sound from the associated device, whereby the operation sound of the injector can be hidden or obscured by the radiant sound from the associated device, and it can be prevented that the operation sound of the injector becomes harsh.

As the associated device, for example, a pump which supplies a fluid to the fuel cell can be applied. As the pump, an air compressor which feeds an oxidizing gas under pressure to the fuel cell is applicable.

Moreover, when the fuel cell system is mounted on a mobile body, as the driving state of the associated device, an operation state of a fan for use in cooling the fuel cell or a motor, or a blower for use in blowing air from an air conditioner of a passenger chamber may be applied.

When such a constitution is employed, for example, the operation sound of the injector is superimposed on the radiant sound from the fan or the like, whereby the operation sound of the injector can be hidden or obscured by the radiant sound from the fan or the like, and it can be prevented that the operation sound of the injector becomes harsh.

Moreover, when the fuel cell system is mounted on the mobile body, as the driving state of the associated device, a movement state of the mobile body, for example, a movement speed or an accelerated state may be applied.

In a case where such a constitution is employed, when the movement speed is high, the injector is operated, whereby the operation sound of the injector can be hidden or obscured by a running sound (e.g., noises of tires on a road or a hissing sound), and it can be prevented that this operation sound becomes harsh.

Furthermore, the injector is operated in the accelerated state, that is, an environment during acceleration in which generation of the hissing sound generated in accordance with the movement (the acceleration) of the mobile body, a noise during braking or the like is not easily noticed, whereby it can be prevented that this operation sound becomes harsh. It is to be noted that the accelerated state of the mobile body has correlation with respect to a generated current of the fuel cell, a demanded load (a demanded amount of the power to be generated) from an electric load (e.g., the motor) connected to the fuel cell or an accelerator open rate, so that the operation of the injector may be controlled based on at least one of these factors.

• Provisional Patent
• Utility Patent

• What Is a Patent?
• What Is a Trademark or Servicemark?
• What Is a Copyright?
• Patent Laws