JP2005123035A - Power supply system using fuel cell car - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To utilize hydrogen mounted on a fuel cell car for supplying electric power to a home 12 most appropriately. <P>SOLUTION: This fuel cell car 11 is provided with a liquid hydrogen tank 14, a fuel cell 13 which generates electricity by making hydrogen supplied from the liquid hydrogen tank 14 react, an evaporation amount detecting means 15 which detects an amount of hydrogen evaporated in the liquid hydrogen tank 14. The home 12 is provided with a DC/AC conversion part 21 which converts a direct current into an alternate current, electric equipment 23, 24 that require electric power, a control device 22 which is installed between the DC/AC conversion part 21 and the electric equipments 23, 24 and which receives the signal from the evaporation amount detecting means 15. A connecting part 20 is installed which electrically connects the fuel cell 13 of the fuel cell car 11 to the DC/AC conversion part 21 of the home 12, and is enabled to supply the electric power generated in the fuel cell 13 to the electric equipment 23, 24 via the connecting part 20 when the amount of the hydrogen evaporated in the liquid hydrogen tank 14 is detected to exceed a prescribed amount by the control device 22. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a power supply system using a fuel cell vehicle, and more particularly, to effectively use electric power of a vehicle equipped with a fuel cell using liquid hydrogen for a vehicle or the like outside the home.

  Conventionally, in a fuel cell vehicle that generates electricity by reacting hydrogen and oxygen, a liquid hydrogen tank that stores liquid hydrogen is mounted on the vehicle. Since liquid hydrogen has an extremely low boiling point of −252.8 ° C. and a large temperature difference from the outside air, the heat from the outside air is transferred to the liquid hydrogen tank and the liquid hydrogen is evaporated. Since liquid hydrogen expands to a volume of about 800 times when it evaporates, the pressure in the liquid hydrogen tank gradually increases, and when it reaches a predetermined pressure, a high-pressure load is applied to the tank wall, which is dangerous. Hydrogen gas is released to the outside from a safety valve normally attached to the tank.

  In this way, it is impossible to store a certain amount or more of evaporated and expanded hydrogen in the fuel cell vehicle. Therefore, when the fuel cell vehicle is not operated while parked in a home garage for a long period (for example, several weeks). There is a problem that hydrogen gas must be released and energy is lost unnecessarily, and there is a risk of explosion when hydrogen is released.

Japanese Patent Application Laid-Open No. 2002-83607 discloses a system for connecting an electric vehicle to a house and supplying electric power to the house side when returning home with an electric vehicle equipped with a polymer electrolyte fuel cell.
However, if power is supplied from the fuel cell on the vehicle side to the house until the amount of hydrogen evaporation in the liquid hydrogen tank is small, hydrogen that is still in a liquid state must be vaporized and reacted in the fuel cell. In other words, the energy that should be originally used for driving the vehicle is used on the house side, which causes a problem of shortening the travelable distance of the vehicle.
JP 2002-83607 A

  The present invention has been made in view of the above-described problems, and supplies electric power to equipment outside the vehicle by effectively using hydrogen gas that must be discharged outside the vehicle out of the liquid hydrogen installed in the fuel cell vehicle. At the same time, it is an object to prevent hydrogen from being consumed more than necessary for equipment outside the vehicle.

In order to solve the above problems, the present invention is a system that uses electric power generated in a fuel cell vehicle as electric power for equipment outside the vehicle,
The fuel cell vehicle includes a liquid hydrogen tank that stores liquid hydrogen as fuel, a fuel cell that generates electricity by reacting hydrogen supplied from the liquid hydrogen tank, and an evaporation that detects the amount of hydrogen evaporation in the liquid hydrogen tank. A quantity detecting means,
The facility outside the vehicle is interposed between a DC / AC converter that converts direct current to alternating current, an electrical device or a power storage device, the DC / AC converter and the device, and from the evaporation amount detecting means. A control device for receiving a signal,
A connecting portion for electrically connecting the fuel cell of the fuel cell vehicle and the DC / AC conversion portion of the outside facility is provided, and the control device detects that the hydrogen evaporation amount in the liquid hydrogen tank exceeds a predetermined amount. Then, the electric power feeding system using the fuel cell vehicle characterized by enabling the electric power generated in the fuel cell to be supplied to the device or the power storage device through the connecting portion is provided.

  With the above configuration, liquid hydrogen is evaporated by external heat in the liquid hydrogen tank to generate hydrogen gas, and when the amount of hydrogen detected by the evaporation amount detection unit exceeds a predetermined amount, the evaporation amount from the evaporation detection unit The fuel cell is operated using the hydrogen gas in the liquid hydrogen tank in response to the command of the control device that has received the signal, and the generated electric power is supplied to the outside facility side through the connection portion, and the The device can be powered. Therefore, the energy efficiency can be increased by effectively using the hydrogen gas in the liquid hydrogen tank that has only been released to the outside of the vehicle. In addition, when the evaporation amount in the liquid hydrogen tank does not exceed the predetermined amount, hydrogen is not used for the facility outside the vehicle, so that the hydrogen that does not need to be released outside the vehicle is consumed more than necessary. It can be avoided.

  The control device of the facility outside the vehicle is connected to another facility and can supply power from the fuel cell to the other facility.

  With the above configuration, when the amount of hydrogen evaporation detected by the evaporation amount detection means exceeds a predetermined value, even if the amount of power used in the facility outside the vehicle is small and the need to supply power is poor, the facility outside the vehicle This can be dealt with by supplying electric power to other equipment. In this case, it is also possible to supply power to equipment near the above-mentioned facility outside the vehicle, or to supply power to a public power distribution network such as a nearby power pole to obtain compensation from the power company.

  As is clear from the above description, according to the present invention, when the hydrogen evaporation amount in the liquid hydrogen tank detected by the evaporation amount detection unit exceeds a predetermined amount, the control device that has received a signal from the evaporation detection unit. The fuel cell is operated using the hydrogen gas in the liquid hydrogen tank, and the generated electric power is supplied to the facility outside the vehicle via the connecting portion and can be used as electric power for the electric device or the power storage device. Therefore, if the amount of hydrogen evaporation in the liquid hydrogen tank does not exceed the predetermined amount, hydrogen is not used for equipment outside the vehicle, and hydrogen that does not need to be released outside the vehicle is consumed more than necessary for equipment outside the vehicle. Can be prevented.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an overall view of a power supply system 10 that uses electric power generated in a fuel cell vehicle 11 as electric power for a home (external facility) 12.

The fuel cell vehicle 11 detects a liquid hydrogen tank 14 that stores liquid hydrogen as fuel, a fuel cell 13 that generates electricity by reacting hydrogen supplied from the liquid hydrogen tank 14 with oxygen, and a pressure in the liquid hydrogen tank 14. A pressure sensor (evaporation amount detection means) 15 for acquiring the hydrogen evaporation amount, and an input / output unit 17 connected to the fuel cell 13 via the power line W1 and connected to the pressure sensor 15 via the signal line W2. And a cable 19 provided with a connector 28 at the tip is led out from the input / output unit 17.
The cable 19 may be led out from the home 12 side and connected by a connector at the input / output unit 17 of the fuel cell vehicle 11.

  The home 12 includes a connection unit 20 that fits and connects the connector 18, a DC / AC conversion unit 21 that converts direct current into AC 100V alternating current, electrical devices 23 and 24 that are household electrical products, and a power storage device 25. The control device 22 is provided between the DC / AC conversion unit 21 and the electric devices 23 and 24 and the power storage device 25, and the control device 22 is connected to the utility pole 26 via the power transmission line W3.

  As shown in FIG. 2, the control device 22 includes a power input unit 29 connected to the connection unit 20 through a power line W1, a signal input / output unit 28 connected to the connection unit 20 through a signal line W2, a switch unit 31 and The control part 27 which has the judgment part 30 and the input means 34 which inputs switching of electric power supply are provided.

  The determination unit 30 is connected to the signal input / output unit 28, receives a signal from the pressure sensor 15 of the fuel cell vehicle 11, and turns on the switch unit when the pressure in the liquid hydrogen tank 14 exceeds a predetermined value to turn the switch unit ON. Electric power is supplied to the devices 23 and 24 side or the power pole 26 side. The determination unit 30 is connected to the input unit 34, and issues a switching command to the switch unit 31 to supply power to either the electrical equipment 23, 24 side or the utility pole 26 side according to the switching input from the input unit 34. Yes.

  Specifically, as shown in FIG. 3, the switch unit 31 includes a first relay unit 32 that cuts off / connects the circuit, and a second relay that switches the power feeding circuit to either the electrical equipment 23, 24 side or the utility pole 26 side. Unit 33, and when the determination unit 30 determines that the pressure in the liquid hydrogen tank 14 exceeds a predetermined value based on a signal from the pressure sensor 15, the first relay unit 32 is closed, while the pressure in the liquid hydrogen tank 14 is When the predetermined value does not exceed the predetermined value, the first relay unit 32 is kept open.

  In addition, when the user selects and inputs power from the input unit 34 to the electric devices 23 and 24 and the power storage device 25 side, the determination unit 30 connects the second relay unit 33 to the electric devices 23 and 24 and the power storage device. When switching to the circuit on the 25th side and selecting and supplying power to the power pole 26 side, the second relay unit 33 is switched from the determination unit 30 to the circuit on the power pole 26 side.

Next, a procedure for using the power supply system 10 will be described.
The connector 18 of the cable 19 is connected to the connection part 20 of the home 12 in a state where the fuel cell vehicle 11 is parked in the garage of the home 12. Then, for example, the electric devices 23 and 24 are selected and input by the input unit 34 of the control device 22 and the second relay unit 33 of the switch unit 31 is switched.

  Thereafter, with the passage of time, the liquid hydrogen in the liquid hydrogen tank 14 evaporates due to the influence of external heat, and the pressure in the liquid hydrogen tank 14 gradually increases. During this time, pressure data in the tank 14 is transmitted from the pressure sensor 15 to the control device 22 via the signal line W2 via the input / output unit 17 → cable 19 → connector 18 → connecting unit 20 → DC / AC conversion unit 21 as needed.

  When the pressure in the liquid hydrogen tank 14 exceeds a predetermined value in the determination unit 30 of the control device 22, the amount of hydrogen evaporation is considered to have exceeded a predetermined amount, and the first relay unit 32 of the switch unit 31 is turned on. At the same time, the determination unit 30 transmits an operation command to the fuel cell 13 through the signal input / output unit 28 → the DC / AC conversion unit 21 → the connection unit 20 → the cable 19 → the input / output unit 17 and Power is supplied to the electrical devices 23 and 24. Therefore, it is possible to effectively use the hydrogen gas that has conventionally only been released from the vehicle by opening the safety valve of the liquid hydrogen tank. The predetermined value needs to be set to a value that does not cause a decrease in strength of the liquid hydrogen tank 14, but the set value varies depending on the type of tank used. In addition, it is preferable to supply power to the power storage device 25 without supplying power to the electrical devices 23 and 24.

  Further, when power generation in the fuel cell 13 progresses and the pressure in the liquid hydrogen tank 14 decreases and the pressure falls below the predetermined value, the determination of the control device 22 that has received the signal from the pressure sensor 15. The first relay unit 32 is opened by the unit 30 and the power generation of the fuel cell 13 is stopped. As described above, when the evaporation amount in the liquid hydrogen tank 14 does not exceed a predetermined amount, that is, when it is not necessary to release the hydrogen gas outside the liquid hydrogen tank 14 for safety, the hydrogen gas for the home 12 is used. Therefore, it is possible to suitably prevent the hydrogen gas from being consumed more than necessary.

Next, in the case where the amount of power used in the electrical devices 23 and 24 in the home 12 is small and the necessity for supplying power is low, and the charging device 25 is not used or there is no charging device 25, the input means By selecting the power pole 26 side as a power supply destination in 34, the determination unit 30 switches the second relay unit 33 to a circuit on the power pole 26 side, and supplies power to the public power distribution network to obtain compensation from the power company. Can do.
Further, power may be supplied to another home near the home 12 without using the power pole 26 of the public distribution network as the power supply destination.

1 is an overall view of a power supply system using a fuel cell vehicle according to an embodiment of the present invention. It is a block diagram which shows a control apparatus. It is a block diagram which shows the principal part of a control apparatus.

Explanation of symbols

10 Power Supply System 11 Fuel Cell Vehicle 12 Home (External Equipment)
13 Fuel cell 14 Liquid hydrogen tank 15 Pressure sensor (evaporation amount detection means)
17 Input / output unit 18 Connector 19 Cable 20 Connection unit 21 DC / AC conversion unit 22 Control devices 23 and 24 Electric equipment 25 Power storage device 26 Utility pole (separate equipment)
27 Control Unit 28 Signal Input / Output Unit 29 Power Input Unit 30 Determination Unit 31 Switch Unit 34 Input Means

Claims (2)

A system that uses electric power generated by a fuel cell vehicle as electric power for an external facility,
The fuel cell vehicle includes a liquid hydrogen tank that stores liquid hydrogen as fuel, a fuel cell that generates electricity by reacting hydrogen supplied from the liquid hydrogen tank, and an evaporation that detects the amount of hydrogen evaporation in the liquid hydrogen tank. A quantity detecting means,
The facility outside the vehicle is interposed between a DC / AC converter that converts direct current to alternating current, an electrical device or a power storage device, the DC / AC converter and the device, and from the evaporation amount detecting means. A control device for receiving a signal,
A connecting portion for electrically connecting the fuel cell of the fuel cell vehicle and the DC / AC conversion portion of the outside facility is provided, and the control device detects that the hydrogen evaporation amount in the liquid hydrogen tank exceeds a predetermined amount. Then, the electric power generation system using the fuel cell vehicle is characterized in that the electric power generated by the fuel cell can be supplied to the device or the power storage device through the connecting portion.   The power supply system using the fuel cell vehicle according to claim 1, wherein the control device of the facility outside the vehicle is connected to another facility so that the power from the fuel cell can be supplied to the other facility.

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