power supply

Abstract

To generate power and supply it to a load even in an environment where no external power supply device exists.SOLUTION: A power supply device is provided with a power storage unit 4. A control unit (main control unit 9, power generation control unit 14, and charge / discharge control unit 22) starts supplying power from the power storage unit 4 to components of a power supply device 1 and starts heating a power generation cell 11 with a heater 3 when a "supply start condition" is satisfied, gradually increases the amount of power generated by the fuel cell power generation unit 2 when a "first condition" is satisfied, terminates the supply of power from the power storage unit 4 to the components of the power supply device 1 when a "second condition" is satisfied, terminates the heating of the power generation cell 11 by the heater 3 when a "third condition" is satisfied, terminates the supply of power from the power supply device 1 to the load when a "supply termination condition" is satisfied, stores the power generated by the fuel cell power generation unit 2 in the power storage unit 4, and terminates the power generation when a predetermined amount of power is stored.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a power supply device that includes a fuel cell power generation unit and is configured to be able to supply power to a load. [Background technology]

[0002] As an example of this type of power supply device, the following patent document discloses a fuel cell power generation system (hereinafter also referred to as a "power generation unit") in the form of a fuel cell power generation unit package (fuel cell power generation unit) that can be installed in an ordinary home or the like.

[0003] This power generation unit is configured to be connected to a commercial grid (commercial AC) to which power loads such as household electrical appliances are connected, and to convert DC power generated by an electrochemical reaction between hydrogen and oxygen into AC power for output. The power generation unit is also provided with a hot water storage unit outlet to allow connection of the hot water storage unit, so that power can be continuously supplied to the hot water storage unit in the event of a loss of the commercial grid (power outage). Specifically, the power generation unit includes a fuel cell main body that generates DC power as described above, and is configured to boost the DC power generated in the fuel cell main body using a booster and then convert it to AC using an inverter, so that AC power similar to that of the commercial grid can be supplied to loads such as the hot water storage unit.

[0004] In addition, this power generation unit has an operation control function that switches between two operation modes depending on the detection results of various sensors, the settings (operation status) of the dip switches, and the operation of the selector switch: grid-connected operation (normal operation), in which power is supplied from the commercial grid to the load, and grid-independent operation (emergency operation), in which power generated in the fuel cell main body is supplied to the load.As a result, when a power outage occurs during grid-connected operation and the power supply from the commercial grid is stopped, the operation control function switches to grid-independent operation, making it possible to continue supplying power to the hot water storage unit, etc. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-143343 A (pages 5-12, figures 1-7) Summary of the Invention [Problem to be solved by the invention]

[0006] However, the power generation units (power supply devices) disclosed in the above patent documents have the following problems to be solved.

[0007] That is, the power generation unit disclosed in the above patent document employs a configuration in which, during grid-connected operation (normal operation), it supplies power obtained from a commercial grid (commercial AC) to a load such as a hot water storage unit, and when power cannot be obtained from the commercial AC due to a power outage or the like, it switches to grid-independent operation (emergency operation) and supplies power generated in the fuel cell main body to the load. In other words, the power generation unit disclosed in the above patent document is configured on the assumption that it will be used in an environment in which power to operate each component of the power generation unit can be obtained from commercial AC before switching to grid-independent operation in which power is generated in the fuel cell main body.

[0008] In this case, this type of power supply device may be used for applications such as starting the device to supply power to a load after a certain amount of time has passed since a power outage, or starting the device to supply power to a load in a location where it is difficult to connect to commercial AC. Furthermore, in the fuel cell power generation unit installed in this type of power supply device, it is necessary to heat the power generation cells and other components to a temperature suitable for power generation when generating power. For example, the power generation unit disclosed in the above patent document is also configured with an FPS heater that uses power from commercial AC or an inverter to heat the components of the power generation unit, and a surplus power heater that uses surplus power to heat the components of the power generation unit.

[0009] However, in the power generating unit disclosed in the above patent document, since the power generating unit cannot be heated by the FPS heater in an environment where power cannot be obtained from commercial AC, it takes a very long time for the fuel cell power generating unit to reach a state where it can generate the power required for the load (or it cannot transition from a stopped state to a state where it can generate power). Therefore, as clearly stated in the "Form for Carrying Out the Invention" of the specification, the power generating unit disclosed in the above patent document employs a configuration in which an external power source such as a general-purpose portable generator is connected to the connection point of the commercial grid, and the components (including the heater) are operated using power obtained from the external power source.

[0010] For this reason, the power generation unit disclosed in the above patent document requires an external power supply to start up the power supply unit itself when a certain amount of time has passed since the power outage (when the power generation unit, which was heated using power from commercial AC, has dropped in temperature) or when used in a location where it is difficult to connect to commercial AC, which poses the problem of low convenience.

[0011] The present invention has been made in consideration of the above-mentioned problems to be solved, and its main object is to provide a power supply device that can generate power using a fuel cell power generation unit and supply power to a load even in an environment where an external power supply device is not present. [Means for solving the problem]

[0012] In order to achieve the above object, the power supply device according to claim 1 comprises a fuel cell power generation unit having a power generation cell, a heating unit that heats the power generation cell, a power storage unit that can store power generated by the fuel cell power generation unit, and a control unit that controls power generation by the fuel cell power generation unit, heating of the power generation cell by the heating unit, and power storage by the power storage unit, and is configured to be able to supply power to a connected load, wherein when a predetermined supply start condition for starting power supply from the power supply device to the load when power generation by the fuel cell power generation unit is not being generated is met, the control unit starts supplying power from the power storage unit to components of the power supply device and starts heating of the power generation cell by the heating unit, so that a first condition is met that enables the fuel cell power generation unit to generate a predetermined first amount of power. When a second condition is met, the amount of power generated by the fuel cell power generation unit is gradually increased, and when a second condition is met that the amount of power generated by the fuel cell power generation unit becomes a predetermined second amount of power generation that is greater than the first amount of power generation, the supply of power from the power storage unit to the components of the power supply device is terminated, and when a third condition is met that the fuel cell power generation unit is able to generate a predetermined third amount of power generation that is greater than the first amount of power generation, the heating unit terminates heating of the power generation cell, and when a predetermined supply termination condition is met that terminates the supply of power from the power supply device to the load, the power supply device terminates the supply of power to the load and stores the power generated by the fuel cell power generation unit in the power storage unit, and when a predetermined amount of power is stored in the power storage unit, power generation by the fuel cell power generation unit is terminated.

[0013] The power supply device of claim 2 is the power supply device of claim 1, wherein the control unit stores the power generated by the fuel cell power generation unit in the storage unit when a predetermined storage start condition is satisfied in a state where the amount of power generated by the fuel cell power generation unit exceeds a predetermined fourth power generation amount that is greater than the second power generation amount and the amount of power supplied to the load is below the fourth power generation amount.

[0014] The power supply device of claim 3 is the power supply device of claim 1 or 2, wherein the control unit starts supplying power from the storage unit to the load when the predetermined supply start condition is satisfied, gradually reduces the amount of power supplied from the storage unit to the load when the first condition is satisfied, and terminates the supply of power from the storage unit to the load when the second condition is satisfied.

[0015] The power supply device of claim 4 is the power supply device of claim 3, wherein when a predetermined discharge start condition is satisfied in a state where the amount of power generated by the fuel cell power generation unit is lower than the amount of power to be supplied to the load, the control unit causes the power generated by the fuel cell power generation unit to be supplied to the load while also causing the storage unit to supply power to the load.

[0016] A power supply device according to claim 5 is the power supply device according to claim 1 or 2, wherein the control unit determines that the supply start condition is satisfied when the commercial AC supplying power to the load is interrupted.

[0017] A power supply device according to a sixth aspect of the present invention is the power supply device according to the fifth aspect, wherein the control unit determines that the supply end condition is satisfied when the supply of power from the commercial AC to the load is resumed. [Effects of the Invention]

[0018] The power supply device of claim 1 comprises a fuel cell power generation unit, a heating unit, a power storage unit, and a control unit, and when a predetermined supply start condition is met when the fuel cell power generation unit is not generating power, the control unit starts supplying power from the power storage unit to the components of the power supply device and starts heating the power generation cells with the heating unit, when a first condition is met under which the fuel cell power generation unit is able to generate a predetermined first amount of power, the control unit gradually increases the amount of power generated by the fuel cell power generation unit, when a second condition is met under which the amount of power generated by the fuel cell power generation unit becomes a predetermined second amount of power, the control unit terminates supplying power from the power storage unit to the components of the power supply device, when a third condition is met under which the fuel cell power generation unit is able to generate a predetermined third amount of power, the control unit terminates heating of the power generation cells with the heating unit, when a predetermined supply termination condition is met, the control unit terminates supplying power from the power supply device to the load and stores the power generated by the fuel cell power generation unit in the power storage unit, and when a predetermined amount of power has been stored in the power storage unit, the control unit terminates power generation by the fuel cell power generation unit.

[0019] Therefore, according to the power supply device of claim 1, even in a situation where power cannot be obtained from commercial AC due to a power outage or in an environment where a connection to commercial AC is not possible, the device can be started using the power stored in the power storage unit, and the heating unit can heat the fuel cell power generation unit (power generation cells) to a temperature where power can be generated appropriately. This eliminates the need for an external power supply device, thereby providing a highly convenient power supply device. Furthermore, when it is no longer necessary to supply power generated by the fuel cell power generation unit to a load, the power required for the next startup is automatically stored in the power storage unit. This means that the power supply device can be immediately started and the supply of power to the load (power generation by the fuel cell power generation unit) can be quickly commenced without having to store power in the power storage unit before starting to use the power supply device, thereby further improving convenience in this respect as well.

[0020] According to the power supply device of claim 2, when a predetermined storage start condition is met in a state where the amount of power generated by the fuel cell power generation unit exceeds a predetermined fourth power generation amount and the amount of power supplied to the load is below the fourth power generation amount, the control unit stores the power generated by the fuel cell power generation unit in the power storage unit.As a result, when power is being supplied from the power supply device to a load, etc., a portion of the power generated by the fuel cell power generation unit (excess power) is automatically stored in the power storage unit, thereby shortening the time required for the process of storing power in the power storage unit when the supply termination condition is met, and power generation by the fuel cell power generation unit can be terminated in a short time.

[0021] According to the power supply device of claim 3, the control unit starts supplying power from the power storage unit to the load when a predetermined supply start condition is satisfied, gradually reduces the amount of power supplied from the power storage unit to the load when a first condition is satisfied, and terminates the supply of power from the power storage unit to the load when a second condition is satisfied, thereby supplying power from the power storage unit to the load when the amount of power generated by the fuel cell power generation unit is insufficient, thereby further improving convenience compared to a configuration in which power is not supplied from the power storage unit to the load. Also, by gradually reducing the amount of power supplied from the power storage unit to the load as the amount of power generated by the fuel cell power generation unit increases, consumption of the power stored in the power storage unit can be reduced, and the time required for storing power in the power storage unit when a supply termination condition is satisfied can be shortened, allowing power generation by the fuel cell power generation unit to be terminated in a short time.

[0022] According to the power supply device of claim 4, when a predetermined discharge start condition is satisfied while the amount of power generated by the fuel cell power generation unit is less than the amount of power to be supplied to the load, the control unit causes the load to be supplied with power generated by the fuel cell power generation unit while also causing the storage unit to supply power to the load.This means that even if the amount of power to be supplied to the load exceeds the amount of power generated by the fuel cell power generation unit, the shortfall in power can be supplied from the storage unit to the load, allowing the load to operate continuously.

[0023] According to the power supply device of claim 5, when the commercial AC supplying power to the load is interrupted, the control unit determines that the supply start condition is satisfied, and thereby the load operating using power obtained from the commercial AC can be operated continuously using the power supplied from the power supply device without stopping the load.

[0024] According to the power supply device of claim 6, when the supply of power from commercial AC to the load is resumed, the control unit determines that the supply termination condition is satisfied, and thereby it is possible to suitably store the power required for the next startup, etc., in the power storage unit without affecting the supply of power to the load. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a configuration diagram of a power supply device 1. [Figure 2] 10 is a flowchart of a power supply process A50. [Figure 3] 10 is a flowchart of a power supply process B60. [Figure 4] 10 is a flowchart of a stoppage process 70. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, an embodiment of a power supply device will be described with reference to the accompanying drawings.

[0027] The power supply device 1 shown in Fig. 1 is an example of a "power supply device" and is configured to generate electricity when supplied with power-generating gases (for example, hydrogen gas and air (atmospheric air: oxygen)) and supply the electricity to various loads. Specifically, the power supply device 1 is configured to include a fuel cell power generation unit 2, a heater 3, a power storage unit 4, an inverter 5, a switching unit 6, an operation unit 7, a display unit 8, a main control unit 9, and a memory unit 10.

[0028] The fuel cell power generation unit 2 is an example of a "fuel cell power generation unit" and includes a power generation cell 11, a flow rate adjustment unit 12, a suction pump 13, and a power generation control unit 14. The power generation cell 11 is an example of a "power generation cell" and is formed by stacking and integrating multiple cells (not shown), each of which has an MEA (membrane electrode assembly for fuel cells) sandwiched between a hydrogen gas separator and an oxygen (air) separator. The flow rate adjustment unit 12 is configured to be connectable to a hydrogen gas source H (e.g., a portable gas tank filled with hydrogen gas), and adjusts the amount of hydrogen gas supplied from the hydrogen gas source H to the power generation cell 11 (hydrogen separator) under the control of the power generation control unit 14. The suction pump 13 is connected to the power generation cell 11 (oxygen separator), and under the control of the power generation control unit 14, draws air (atmospheric air) from the power generation cell 11 to introduce new air into the power generation cell 11.

[0029] The heater 3 is an example of a "heating unit" and heats the power generation cells 11 in the fuel cell power generation unit 2 under the control of the main control unit 9. The power storage unit 4 is an example of a "power storage unit" and includes a battery 21 and a charge / discharge control unit 22. The battery 21 is formed, for example, from a lithium-ion battery, and under the control of the charge / discharge control unit 22, stores the power generated by the fuel cell power generation unit 2 and supplies (discharges) the stored power to each component of the power supply device 1 and an external load. The charge / discharge control unit 22 controls the storage of power in the battery 21 and the discharge of power from the battery 21 under the control of the main control unit 9.

[0030] The inverter 5 converts the DC power generated by the fuel cell power generation unit 2 and the DC power output from the power storage unit 4 into AC and outputs the AC power. The switching unit 6 is configured, for example, to be connectable to commercial AC and to be connectable to various loads to which power is supplied from the power supply device 1, and supplies the loads with power obtained from the commercial AC and / or power output from the fuel cell power generation unit 2 or the power storage unit and converted to AC by the inverter 5 under the control of the main control unit 9. The switching unit 6 also outputs a signal to the main control unit 9 that can identify whether or not commercial AC is being supplied (whether or not a power outage has occurred). The operation unit 7 has operation switches that can perform various setting operations for the operating conditions of the power supply device 1, and outputs an operation signal to the main control unit 9 in response to switch operation. The display unit 8 displays various display screens (not shown) that indicate the operating status of the power supply device 1 under the control of the main control unit 9.

[0031] The main control unit 9 performs overall control of the power supply device 1. Specifically, the main control unit 9 controls power generation by the fuel cell power generation unit 2 (control of power generation by the power generation control unit 14), heating of the power generation cells 11 by the heater 3, and storage and discharge by the power storage unit 4 (control of storage and discharge by the charge / discharge control unit 22). In this case, in the power supply device 1 of this example, the power generation control unit 14 of the fuel cell power generation unit 2, the charge / discharge control unit 22 of the power storage unit 4, and the main control unit 9 work together to form a "control unit." The various controls performed by the main control unit 9, the power generation control unit 14, and the charge / discharge control unit 22 will be described in detail later. The memory unit 10 stores the operating program of the main control unit 9 and various data related to the settings of the operating conditions of the power supply device 1.

[0032] This power supply device 1 is configured to be capable of operating in two ways: as an emergency power supply device that continues to supply power to a load when a power outage or other condition occurs in a location where connection to commercial AC makes it impossible to supply power from commercial AC, and as a stand-alone power supply device that supplies power to a load in an environment where power cannot be obtained from commercial AC.

[0033] First, a method for using the device as an emergency power supply will be described.

[0034] When used as an emergency power supply, first, the power supply device 1 is installed in a location where it can supply power to the load to be powered. The hydrogen gas source H is connected to the flow rate regulator 12, and the commercial AC and the load are connected to the switching unit 6. Next, the operation unit 7 is operated to start the power supply device 1. At this time, the main control unit 9 determines, based on a signal from the switching unit 6, that the commercial AC is connected to the switching unit 6 (that power can be obtained from the commercial AC) and supplies the power supplied from the commercial AC directly to the load. As a result, the required power is supplied from the commercial AC to the load via the power supply device 1. In addition, in parallel with supplying power to the load, the main control unit 9 continuously monitors, based on a signal from the switching unit 6, whether power can be obtained from the commercial AC. Note that, in this state where power generation by the fuel cell power generation unit 2 has not started and power is being supplied from the commercial AC, the main control unit 9 and other components are operated by DC power obtained from the commercial AC and converted by an AC / DC converter (not shown).

[0035] On the other hand, when the supply of power from the commercial AC is stopped due to a power outage or the like (an example of "when a predetermined 'supply start condition' for starting the supply of power from the power supply device to the load when no power is being generated by the fuel cell power generation unit is satisfied" and an example of "when the commercial AC is interrupted"), the main control unit 9 starts the power supply process A50 shown in Fig. 2. This power supply process A50 is a process executed when power generation by the fuel cell power generation unit 2 is started, and the main control unit 9 first controls the charge / discharge control unit 22 to discharge the power stored in the battery 21 and start the supply of power to each component within the device (an example of a process of "starting the supply of power from the power storage unit to the components of the power supply device"), and also starts the supply of power to the load via the switching unit 6 (an example of a process of "starting the supply of power from the power storage unit to the load": step 51).

[0036] Next, the main control unit 9 controls the heater 3 to start heating the power generation cell 11 in the fuel cell power generation unit 2 (an example of a process of "starting heating of the power generation cell by the heater") and controls the power generation control unit 14 to start supplying hydrogen gas to the power generation cell 11 and suctioning air from the power generation cell 11 (step 52). At this time, the heater 3 heats the power generation cell 11 with power output from the power storage unit 4, and the power generation control unit 14 controls the flow rate adjustment unit 12 to start supplying hydrogen gas from the hydrogen gas source H to the power generation cell 11 and controls the suction pump 13 to start suctioning air from the power generation cell 11. As a result, the temperature of the power generation cell 11 gradually increases, and hydrogen and air (oxygen) are supplied to the power generation cell 11, starting power generation in the fuel cell power generation unit 2. The main control unit 9 also monitors whether a "first condition" that enables the fuel cell power generation unit 2 to generate a "predetermined first amount of power" is satisfied (step 53).

[0037] In this case, immediately after starting power generation by the fuel cell power generation unit 2, the temperature of the power generation cells 11 has not yet risen to a temperature at which suitable power generation is possible. Even if hydrogen or air (oxygen) is supplied to such power generation cells 11, the fuel cell power generation unit 2 cannot stably output power to the inverter 5. Therefore, to start using the power generated by the fuel cell power generation unit 2, for example, it is necessary to define the minimum amount of power that can be stably output from the power generation cells 11 to the inverter 5 as the "first power generation amount," and determine whether or not a state has been reached in which power generation is possible at such an amount, i.e., whether or not a state in which power can be stably output from the fuel cell power generation unit 2 to the inverter 5 has been reached (whether or not the "first condition" has been satisfied). Note that in this example, for example, a configuration is employed in which it is determined that the "first condition" has been satisfied when the temperature of the power generation cells 11 has risen to a temperature at which suitable power generation is possible at the "first power generation amount."

[0038] Furthermore, when the above-mentioned "first condition" is satisfied, the main control unit 9 continues heating the power generation cell 11 with the heater 3 while controlling the power generation control unit 14 to gradually increase the amount of power generated by the fuel cell power generation unit 2 (step 54). At this time, the power generation control unit 14 controls the flow rate adjustment unit 12 to gradually increase the amount of hydrogen gas supplied from the hydrogen gas source H to the power generation cell 11, and controls the suction pump 13 to gradually increase the amount of air suctioned from the power generation cell 11. As a result, the temperature of the power generation cell 11 is further increased by heating with the heater 3, and hydrogen and air (oxygen) necessary for suitable power generation are supplied to the power generation cell 11, gradually increasing the amount of power generated by the fuel cell power generation unit 2.

[0039] At this time, as the amount of power generated increases, the amount of power output from the fuel cell power generation unit 2 gradually increases, and this power is supplied to each component of the power supply device 1, converted to AC by the inverter 5, and supplied to the load via the switching unit 6. Therefore, the main control unit 9 controls the charge / discharge control unit 22 to reduce the amount of power supplied from the power storage unit 4 to each component of the power supply device 1 and the load by the amount that the amount of power generated by the fuel cell power generation unit 2 and supplied to each component of the power supply device 1 and the load has increased (step 55). This gradually reduces the amount of power consumed per unit time of the power stored in the power storage unit 4. The main control unit 9 also determines whether a "second condition" that enables the fuel cell power generation unit 2 to generate a "predetermined second amount of power" is met (step 56), and if the "second condition" is not met, the process proceeds to step 58, which will be described later.

[0040] In this case, when the amount of power generated by the fuel cell power generation unit 2 has increased sufficiently, the power required by the load can be supplied from the power supply device 1 without the need to supply power to the load from the power storage unit 4. Therefore, in this example used as an emergency power supply, as an example, the amount of power supplied from the power supply device 1 to each component of the power supply device 1 and the load immediately before power generation by the fuel cell power generation unit 2 began (i.e., when power obtained from commercial AC was being supplied to the load), is defined as the "second amount of power generation," and when the amount of power generated by the fuel cell power generation unit 2 has increased to this amount of power generation, it is determined that the "second condition" has been met. Furthermore, when the "second condition" is met, the main control unit 9 controls the charge / discharge control unit 22 to terminate the supply of power from the power storage unit 4 to each component of the power supply device 1 and the load (discharge from the battery 21) (step 57).

[0041] The main control unit 9 also determines whether a "third condition" that enables the fuel cell power generation unit 2 to generate a "predetermined third amount of power" is met (step 58). If the "third condition" is not met, the process returns to step 56. In this case, when the temperature of the power generation cell 11 is sufficiently raised by heating by the heater 3, the reaction between hydrogen and air (oxygen) makes it possible to generate suitable power. Furthermore, after a certain amount of time has passed since the power generation by the power storage unit 4 started, the temperature of the power generation cell 11 rises due to the reaction between hydrogen and air (oxygen) in the power generation cell 11, in addition to the heating by the heater 3. Therefore, if the heater 3 continues to heat the power generation cell 11, the temperature of the power generation cell 11 will rise more than necessary due to the heat generated by the heater 3.

[0042] Therefore, the power supply device 1 of this example is configured to stop heating the power generation cell 11 by the heater 3 when it determines whether the temperature of the power generation cell 11 has risen to a temperature at which the fuel cell power generation unit 2 can generate the amount of power required by the components and loads of the power supply device 1. That is, in this example, the amount of power equal to the above-mentioned "second amount of power generation," which is the amount of power supplied to the components and loads of the power supply device 1 immediately before the fuel cell power generation unit 2 started generating power, is defined as the "third amount of power generation," and when the amount of power generation by the fuel cell power generation unit 2 has increased to this amount of power generation, it is determined that the "third condition" has been met. Furthermore, when the "third condition" is met, the main control unit 9 controls the heater 3 to stop heating the power generation cell 11 to prevent an excessive rise in temperature of the power generation cell 11 (step 59), and starts the power supply process B60 shown in FIG. 3.

[0043] This power supply process B60 is a process that is executed when stable power generation is possible by the fuel cell power generation unit 2, and in parallel with the process of power generation by the fuel cell power generation unit 2 and power supply to the load via the switching unit 6, the main control unit 9 repeatedly determines whether the ``storage start condition'' is satisfied (step 61), whether the ``discharge start condition'' is satisfied (step 62), and whether the ``supply end condition'' is satisfied (step 63).

[0044] In this case, the power supply device 1 of this example is configured to determine that the "power storage start condition" is satisfied when, for example, the amount of power generated by the fuel cell power generation unit 2 is 1.1 times the amount of power to be supplied to the components and loads of the power supply device 1 (the amount of power generated by the fuel cell power generation unit 2 exceeds the amount of power required at the supply destination, which is an example of a "state in which the amount of power generated by the fuel cell power generation unit exceeds a predetermined fourth amount of power generated that is greater than the second amount of power generated, and the amount of power supplied to the load is less than the fourth amount of power generated") and a predetermined waiting time (for example, 10 seconds) has elapsed since this state was reached when the amount of power generated by the fuel cell power generation unit 2 is 80% or less of its available storage capacity (the amount of power generated resulting in a 10% surplus power amount), and to determine whether the "power storage start condition" is satisfied.

[0045] Furthermore, in the power supply device 1 of this example, when the amount of electricity stored (remaining amount) in the battery 21 is 70% or more of the available storage capacity, the amount of electricity to be supplied to each component or load of the power supply device 1 exceeds the amount of electricity generated by the fuel cell power generation unit 2 (i.e., the amount of electricity generated by the fuel cell power generation unit 2 is less than the amount of electricity required at the supply destination), and a predetermined waiting time (10 seconds, for example) has elapsed since this state was reached, a configuration is adopted in which it is determined that the "discharge start condition" has been met. Note that the values of the "amount of electricity stored (remaining amount)," "excess electricity amount," and "waiting time" in the above-mentioned "electricity storage start condition" and "discharge start condition" can be changed and set as desired by operating the operation unit 7.

[0046] Furthermore, in the power supply device 1 of this example, when an operation to stop the supply of power to the load (off operation) is performed, or when a state occurs in which there is no load to supply power to (such as when the load is stopped or the load is disconnected from the switching unit 6), and there is no longer a need to continue supplying power to the load, a configuration is adopted in which, when a predetermined waiting time (for example, 10 seconds) has elapsed since this state occurred, it is determined that a ``supply termination condition'' (an example of a ``predetermined supply termination condition for terminating the supply of power from the power supply device to the load'') has been met.

[0047] At this time, when the aforementioned "power storage start condition" is satisfied, main control unit 9 controls charge / discharge control unit 22 to start storing the power generated by fuel cell power generation unit 2 in power storage unit 4 (step 64), in parallel with supplying the power required by each component and load of power supply device 1. Specifically, when the amount of power stored (remaining amount) of battery 21 is below 50% of the available power storage capacity, charge / discharge control unit 22 uses the power output from fuel cell power generation unit 2 to rapidly charge battery 21 (a power storage process in which a large amount of power is stored per unit time), and when the amount of power stored (remaining amount) of battery 21 is within a range of 50% to 80% of the available power storage capacity, charge / discharge control unit 22 uses the power output from fuel cell power generation unit 2 to normally slow-charge battery 21 (a power storage process in which a small amount of power is stored per unit time).

[0048] As a result, the power consumed immediately after the start of the power supply process A50 described above is stored in the power storage unit 4 (battery 21). Although detailed description will be omitted, when the amount of power required by the components and loads of the power supply device 1 becomes equal to or greater than the amount of power generated by the fuel cell power generation unit 2, the main control unit 9 controls the charge / discharge control unit 22 to immediately terminate the storage of power in the battery 21 and causes all of the power generated by the fuel cell power generation unit 2 to be supplied to the components and loads of the power supply device 1. Furthermore, when the amount of power stored in the power storage unit 4 (battery 21) reaches a specified value (for example, 90% of the available storage capacity) by continuing the process of step 64, the charge / discharge control unit 22 terminates the storage of power in the battery 21 and notifies the main control unit 9 that the storage has been terminated. In response, the main control unit 9 controls the power generation control unit 14 to reduce the amount of power generated by the fuel cell power generation unit 2. This prevents the fuel cell power generation unit 2 from generating unnecessary power.

[0049] Furthermore, when the aforementioned "discharge start condition" is satisfied, the main control unit 9 controls the charge / discharge control unit 22 to start supplying power from the power storage unit 4 (step 65), while continuing to supply power generated by the fuel cell power generation unit 2 to each component and load of the power supply device 1. At this time, the charge / discharge control unit 22 discharges power from the battery 21 and supplies it to each component of the power supply device 1. Furthermore, the inverter 5 converts the power supplied from the power storage unit 4 into AC power and outputs it to the switching unit 6.

[0050] Although detailed description will be omitted, in the fuel cell unit 1 of this example, when the amount of power generated by the fuel cell power generation unit 2 falls below the upper limit of its power generation capacity and the amount of power to be supplied to each component and load of the power supply device 1 exceeds the amount of power generated by the fuel cell power generation unit 2 at that time, the main control unit 9 controls the power generation control unit 14 to increase the amount of power generated by the fuel cell power generation unit 2. However, even if the amount of hydrogen gas and air supplied to the power generation cells 11 is increased according to the required amount of power generation, it takes some time for the fuel cell power generation unit 2 to output a sufficient amount of power. Therefore, by using the power output from the fuel cell power generation unit 2 together with the power output from the power storage unit 4, it is possible to avoid situations where power shortages occur in the components and loads of the power supply device 1.

[0051] On the other hand, when the aforementioned "supply termination condition" is satisfied, the main control unit 9 initiates the shutdown process 70 shown in Fig. 4. This shutdown process 70 is executed immediately before power generation by the fuel cell power generation unit 2 is terminated. The main control unit 9 first terminates the supply of power from the power supply device 1 to the load (step 71) and determines whether the amount of stored power in the power storage unit 4 (battery 21) is equal to or less than a specified value (e.g., 90% of the available storage capacity) (step 72). If the amount of stored power is equal to or greater than the specified value, the main control unit 9 controls the power generation control unit 14 to terminate power generation by the fuel cell power generation unit 2 (step 73), thereby terminating the shutdown process 70. At this time, the power generation control unit 14 controls the flow rate adjustment unit 12 to terminate the supply of hydrogen gas from the hydrogen gas source H to the power generation cell 11 and controls the suction pump 13 to terminate the suction of air (oxygen) from the power generation cell 11 (i.e., the supply of air (oxygen) to the power generation cell 11). This causes the fuel cell power generation unit 2 to stop generating power, and the power supply device 1 goes into a stopped state.

[0052] On the other hand, when the amount of stored power in the power storage unit 4 (battery 21) is equal to or less than the specified value, the main control unit 9 controls the charge / discharge control unit 22 to start storing the power generated by the fuel cell power generation unit 2 in the power storage unit 4 (step 74). At this time, the charge / discharge control unit 22 causes the battery 21 to store the power output from the fuel cell power generation unit 2. As a result, the power consumed immediately after the start of the above-mentioned power supply process A50 is sequentially stored in the power storage unit 4 (battery 21). Next, the main control unit 9 monitors whether the amount of stored power in the power storage unit 4 (battery 21) has reached a specified value (step 75). Furthermore, when the amount of stored power reaches the specified value (an example of "when a predetermined amount of power has been stored in the power storage unit"), the main control unit 9 controls the power generation control unit 14 to end power generation by the fuel cell power generation unit 2 (step 73), and ends this shutdown process 70. As a result, power generation by the fuel cell power generation unit 2 ends, and the power supply device 1 enters a shutdown state.

[0053] Although detailed description will be omitted, in the power supply device 1 of this example, when the supply of commercial AC is resumed while the above-described power supply process A50 or power supply process B60 is being executed and power obtained from the commercial AC becomes available to be supplied to the components and loads of the power supply device 1, the main control unit 9 controls the power generation control unit 14 to terminate power generation by the fuel cell power generation unit 2, and controls the charge / discharge control unit 22 to store the power obtained by converting the commercial AC into DC in the battery 21. Furthermore, when the amount of power stored in the power storage unit 4 reaches a specified value, the main control unit 9 controls the charge / discharge control unit 22 to terminate storage of power in the charge / discharge control unit 22. As a result, the power consumed immediately after the start of the above-described power supply process A50 is stored in the power storage unit 4 (battery 21).

[0054] Next, a method for using the device as a stand-alone power supply will be described. Note that duplicated explanations of processes similar to those performed when the device is used as the above-mentioned emergency power supply will be omitted.

[0055] When used as a stand-alone power supply, first, the power supply device 1 is installed in a location where it can supply power to the load to be supplied with power, the hydrogen gas source H is connected to the flow rate adjusting unit 12, and the load is connected to the switching unit 6. Next, the operation unit 7 is operated to start the power supply device 1. At this time, unlike when used as an emergency power supply, commercial AC is not connected to the switching unit 6, so the main control unit 9 and other components are started using the power stored in the power storage unit 4. Furthermore, based on a signal from the switching unit 6, the main control unit 9 determines that commercial AC is not connected to the switching unit 6 (commercial AC is not being supplied). In this state, when an instruction to start supplying power to the load is given by operating the operation unit 7 (another example of "when a predetermined 'supply start condition' for starting the supply of power from the power supply device to the load when power generation by the fuel cell power generation unit is not being generated is satisfied"), the main control unit 9 executes the power supply process A50 shown in FIG. 2.

[0056] In the power supply process A50 executed when the device is used as a stand-alone power supply, the power stored in the power storage unit 4 is supplied to the load until the power generation cells 11 are sufficiently heated by the heater 3 and the fuel cell power generation unit 2 is in a state where a stable and sufficient amount of power can be generated. As a result, the power required by the load is supplied from the power supply device 1 immediately after issuing a power supply instruction. Furthermore, when the temperature of the power generation cells 11 has risen sufficiently due to heating by the heater 3 and their own heat generation associated with power generation and the fuel cell power generation unit 2 is in a state where a stable and sufficient amount of power can be generated (when the "third condition" is satisfied), the power generated by the fuel cell power generation unit 2 is supplied to the load, replacing the power supply from the power storage unit 4 to the load. As a result, the required power can be supplied from the power supply device 1 to the load even in an environment where it is not possible to connect to commercial AC.

[0057] Furthermore, when the "third condition" is met and heating of the power generation cell 11 by the heater 3 is terminated, the aforementioned power supply process B60 is executed. Furthermore, when the "supply termination condition" is met, the aforementioned shutdown process 70 is executed. As a result, the power supply device 1 is shut down in a state where the power storage unit 4 has stored therein the electric power required to restart power generation by the fuel cell power generation unit 2 in the stopped state of the power supply device 1.

[0058] In this way, this power supply device 1 comprises the fuel cell power generation unit 2, heater 3, power storage unit 4 and control unit (main control unit 9, power generation control unit 14 and charge / discharge control unit 22), and when a predetermined "supply start condition" is satisfied while the fuel cell power generation unit 2 is not generating power, the control unit starts supplying power from the power storage unit 4 to the components of the power supply device 1 and the load, and starts heating the power generation cell 11 with the heater 3, and when a "first condition" is satisfied under which the fuel cell power generation unit 2 can generate a predetermined "first power generation amount", the control unit gradually increases the amount of power generated by the fuel cell power generation unit 2 and gradually decreases the amount of power supplied from the power storage unit 4 to the load. When a "second condition" is met under which the amount of power generated by the fuel cell power generation unit 2 becomes a predetermined "second power generation amount," the supply of power from the power storage unit 4 to the components of the power supply device 1 and the load is terminated; when a "third condition" is met under which the fuel cell power generation unit 2 is able to generate a predetermined "third power generation amount," the heating of the power generation cell 11 by the heater 3 is terminated; when a predetermined "supply termination condition" is met, the supply of power from the power supply device 1 to the load is terminated, and the power generated by the fuel cell power generation unit 2 is stored in the power storage unit 4; and when the predetermined amount of power has been stored in the power storage unit 4, power generation by the fuel cell power generation unit 2 is terminated.

[0059] Therefore, with this power supply device 1, even in situations where power cannot be obtained from commercial AC due to a power outage or in an environment where a connection to commercial AC is not possible, the device can be started using the power stored in the power storage unit 4, and the heater 3 can heat the fuel cell power generation unit 2 (power generation cells 11) to a temperature where power can be suitably generated. This eliminates the need for an external power supply device, making it possible to provide a highly convenient power supply device 1. Furthermore, when it is no longer necessary to supply power generated by the fuel cell power generation unit 2 to a load, the power required for the next startup, etc., is automatically stored in the power storage unit 4. This means that the power supply device 1 can be started immediately and the supply of power to the load, etc. (power generation by the fuel cell power generation unit 2) can be quickly commenced without having to store power in the power storage unit 4 before starting to use the power supply device 1, thereby further improving convenience in this respect as well.

[0060] Furthermore, according to this power supply device 1, when a predetermined "storage start condition" is satisfied in a state where the amount of power generated by the fuel cell power generation unit 2 exceeds a predetermined "fourth amount of power generation" and the amount of power supplied to the load is below the "fourth amount of power generation," the control unit stores the power generated by the fuel cell power generation unit 2 in the power storage unit 4.As a result, when power is being supplied from the power supply device 1 to a load, etc., a portion of the power generated by the fuel cell power generation unit 2 (excess power) is automatically stored in the power storage unit 4.This reduces the time required for the process of storing power in the power storage unit 4 when the "supply end condition" is satisfied, and makes it possible to end power generation by the fuel cell power generation unit 2 in a short time.

[0061] Furthermore, with this power supply device 1, the control unit starts supplying power from the power storage unit 4 to the load when a predetermined "supply start condition" is met, gradually reduces the amount of power supplied from the power storage unit 4 to the load when a "first condition" is met, and ends the supply of power from the power storage unit 4 to the load when a "second condition" is met. This allows power to be supplied from the power storage unit 4 to the load when the amount of power generated by the fuel cell power generation unit 2 is insufficient, thereby further improving convenience compared to a configuration in which power is not supplied from the power storage unit 4 to the load. Furthermore, by gradually reducing the amount of power supplied from the power storage unit 4 to the load as the amount of power generated by the fuel cell power generation unit 2 increases, consumption of the power stored in the power storage unit 4 can be reduced, and the time required for storing power in the power storage unit 4 when a "supply end condition" is met can be shortened, allowing power generation by the fuel cell power generation unit 2 to be ended in a short time.

[0062] Furthermore, according to this power supply device 1, when a predefined "discharge start condition" is satisfied while the amount of power generated by the fuel cell power generation unit 2 is less than the amount of power that should be supplied to the load, the control unit causes the load to be supplied with power generated by the fuel cell power generation unit 2 while also causing the storage unit 4 to supply power to the load.This means that even if the amount of power that should be supplied to the load exceeds the amount of power generated by the fuel cell power generation unit 2, the shortfall in power can be supplied from the storage unit 4 to the load, allowing the load to operate continuously.

[0063] Furthermore, according to this power supply device 1, when the commercial AC supplying power to the load is cut off, the control unit determines that the "supply start condition" has been met, and thereby the load operating using power obtained from the commercial AC can be operated continuously using the power supplied from the power supply device 1 without stopping the load.

[0064] Furthermore, according to this power supply device 1, when the supply of power from commercial AC to the load is resumed, the control unit determines that the "supply termination condition" has been satisfied, and thereby the power required for the next startup, etc., can be suitably stored in the power storage unit 4 without affecting the supply of power to the load.

[0065] The configuration of the "power supply device" is not limited to the example of the configuration of the power supply device 1 described above.

[0066] For example, while a configuration capable of being connected to commercial AC has been described as an example, it is also possible to adopt a configuration that does not include components for supplying commercial AC to a load, etc., and that can be used only in the aforementioned standalone power supply mode. Also, while a configuration in which a portable gas tank filled with hydrogen gas is connected to flow rate regulator 12 as hydrogen gas source H and hydrogen gas is supplied from hydrogen gas source H to power generation cell 11 has been described as an example, it is also possible to adopt a configuration in which a hydrogen gas generator is connected as hydrogen gas source H and hydrogen gas is supplied to power generation cell 11, or a configuration in which existing hydrogen gas supply piping is connected as hydrogen gas source H and hydrogen gas is supplied to power generation cell 11. Furthermore, a gas tank or generator serving as hydrogen gas source H can be installed as a component of the "power supply." [Explanation of symbols]

[0067] 1 Power supply 2. Fuel cell power generation section 3 Heater 4. Power storage unit 5 inverters 6 Switching section 7 Control section 8 Display 9 Main control unit 10 Storage section 11 Power generation cell 12 Flow rate adjustment section 13 Suction pump 14 Power generation control unit 21 Battery 22 Charge / discharge control unit 50 Power Supply Processing A 60 Power Supply Processing B 70 Stop processing H Hydrogen gas source

Claims

1. a fuel cell power generation unit including a power generation cell; a heating unit that heats the power generation cell; a power storage unit capable of storing the electric power generated by the fuel cell power generation unit; a control unit that controls power generation by the fuel cell power generation unit, heating of the power generation cell by the heating unit, and power storage by the power storage unit, and is configured to be able to supply power to a connected load, The control unit When a predetermined supply start condition for starting the supply of power from the power supply device to the load while the fuel cell power generation unit is not generating power is satisfied, the power storage unit starts supplying power to the components of the power supply device and the heating unit starts heating the power generation cells; when a first condition for enabling the fuel cell power generation unit to generate a predetermined first amount of power is satisfied, the amount of power generated by the fuel cell power generation unit is gradually increased; when a second condition for enabling the fuel cell power generation unit to generate a predetermined second amount of power that is greater than the first amount of power is satisfied, the power storage unit stops supplying power to the components of the power supply device; and when a third condition for enabling the fuel cell power generation unit to generate a predetermined third amount of power that is greater than the first amount of power is satisfied, the heating unit stops heating the power generation cells. A power supply device that terminates the supply of power from the power supply device to the load when a predetermined supply termination condition for terminating the supply of power from the power supply device to the load is satisfied, and that stores the power generated by the fuel cell power generation unit in the storage unit, and terminates power generation by the fuel cell power generation unit when a predetermined amount of power has been stored in the storage unit.

2. 2. The power supply device according to claim 1, wherein the control unit causes the power generated by the fuel cell power generation unit to be stored in the storage unit when a predetermined storage start condition is satisfied in a state in which the amount of power generated by the fuel cell power generation unit exceeds a predetermined fourth power generation amount that is greater than the second power generation amount and the amount of power supplied to the load is below the fourth power generation amount.

3. 3. The power supply device according to claim 1, wherein the control unit starts supplying power from the power storage unit to the load when the predetermined supply start condition is satisfied, gradually reduces the amount of power supplied from the power storage unit to the load when the first condition is satisfied, and terminates the supply of power from the power storage unit to the load when the second condition is satisfied.

4. 4. The power supply device according to claim 3, wherein when a predetermined discharge start condition is satisfied in a state in which the amount of power generated by the fuel cell power generation unit is lower than the amount of power to be supplied to the load, the control unit causes the load to be supplied with power generated by the fuel cell power generation unit while also causing the storage unit to supply power to the load.

5. 3. The power supply device according to claim 1, wherein the control unit determines that the supply start condition is satisfied when a commercial AC power supply that supplies power to the load is interrupted.

6. 6. The power supply device according to claim 5, wherein the control unit determines that the supply termination condition is satisfied when the supply of power from the commercial AC to the load is resumed.

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