JP2003032906A - Power supply unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply unit which permits a storage battery for maintaining adequate storage performance, for as long a period as possible by avoiding the disadvantage of its storage battery deteriorating at an early stage. SOLUTION: This power supply unit includes the storage battery 5, which stores surplus power of a fuel cell 1 and outputs the stored power to the outside if the fuel cell, is short of output, a power consumption means 4 which consumes surplus power, a charging state detection means 6 which detects the charging state of the storage battery, and a control means 12 which controls the operating conditions of the power supply unit. If the power generated in the fuel cell 1 is smaller than the load power, the power stored in the storage battery 5 is outputted to the outside, and if the output generated in the fuel cell 1 is larger than the load power and is not fully charged, the surplus power is stored in the storage battery 5. If it is fully charged, then the surplus power is consumed with the power consumption means; and when the storage battery 5 stays fully charged for over a specified time interval, the power stored in the storage battery is consumed with the power consumption means 40.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell for outputting generated electric power to the outside, an excessive electric power of the fuel cell, and an electric power stored when the output of the fuel cell is insufficient. A storage battery for power consumption, a power consumption unit that consumes the surplus power, a charging state detection unit that detects the charging state of the storage battery, and a management unit that manages the operating state of the power supply device. If the power is less than the load power of the external power load, the power stored in the storage battery is output to the outside, and if the generated power of the fuel cell is greater than the load power, the storage battery is not in a fully charged state. The present invention relates to a power supply device configured to store the surplus power in the storage battery and to consume the surplus power by the power consuming unit in the fully charged state.

[0002]

2. Description of the Related Art In a power supply device having the above-mentioned structure, for example, electric power is generated by a fuel cell that generates electric power by utilizing an electrochemical reaction between hydrogen and oxygen. The fuel cell regulates its output. In this case, the output adjustable amount per unit time is relatively small, and it is difficult to perform frequent output adjustment. Therefore, in such a power supply device using a fuel cell, when the output power of the fuel cell is excessive with respect to the external power load, the surplus is stored in the storage battery, while the power generation of the fuel cell is performed with respect to the external power load. When the electric power is insufficient, the electric power stored in the power storage unit is output. In the power supply device having such a configuration, even when the surplus power of the fuel cell is configured to be stored in the power storage unit, the storage battery has a limited capacity to store the surplus power in the storage battery. However, if the storage battery is in a fully charged state, it cannot store any more electricity. In such a case, the surplus power is consumed by the power consumption means. Then, in the power supply device having such a configuration, conventionally, when the generated power of the fuel cell is larger than the load power of the external power load, it is detected that the storage battery is in the chargeable state instead of the fully charged state. If it is, the storage battery is charged with the surplus power, but if the storage battery is in a fully charged state and cannot be further charged, the surplus power of the fuel cell is supplied to the power consumption means so that the storage battery is not further charged. It was designed to be consumed. That is, at this time, the storage battery was in a state where neither charging operation nor discharging operation was performed.

[0003]

In the above conventional configuration, when the storage battery is fully charged, the surplus power in the fuel cell is consumed by the power consuming means to effectively use the generated power without wasting it. However, there is still room for improvement in the following points.

By the way, as a storage battery used in such a power supply device, for example, a storage battery may be constructed by connecting a number of lithium ion batteries or the like in series. In such a storage battery, the charged state is full. If the state of being in a charged state continues for a long time, the power storage performance may deteriorate, and for example, in a short-term use, there is a possibility that the charging voltage drops early and the battery cannot be used.

In the above structure, the generated power output from the fuel cell is set to an appropriate value so as to reduce the surplus power and the insufficient power as much as possible in accordance with the magnitude of the external power load predicted in advance. However, the external power load is not always constant and changes according to the usage situation of the power user, and it is possible that the power load that is less than the initially predicted power load continues for a long time. However, in the above conventional configuration, when the state in which the generated power of the fuel cell is larger than the external power load continues for a long time, the state in which the storage battery is fully charged continues for a long time. There is a possibility that the storage performance of such a storage battery deteriorates and the charging voltage drops early due to short-term use.

The present invention has been made by paying attention to such a point, and an object thereof is to avoid the disadvantage that the storage battery deteriorates at an early stage, and to maintain the proper storage performance of the storage battery for a period as long as possible. The point is to provide a power supply device.

[0007]

According to a first aspect of the present invention, there is provided a fuel cell for outputting generated electric power to the outside, and surplus electric power of the fuel cell, and electric power stored when the output of the fuel cell is insufficient. A storage battery for outputting to the outside, a power consumption means for consuming the surplus power, a charging state detection means for detecting the charging state of the storage battery, and a management means for managing the operating state of the power supply device, If the generated power of the fuel cell is less than the load power of the external power load, the power stored in the storage battery is output to the outside, and if the generated power of the fuel cell is greater than the load power, the storage battery is full. In the power supply device configured to store the surplus power in the storage battery if it is not in the charging state and to consume the surplus power in the power consuming means in the fully charging state, However, when the state in which the storage battery is in the fully charged state continues for a set time or more, it is configured to execute a storage battery discharge process that causes the power consumption means to consume the electric power stored in the storage battery. And

That is, if the generated power of the fuel cell is smaller than the external power load, the output of the fuel cell is insufficient, so the power stored in the storage battery is output to the outside. If the power generated by the fuel cell is larger than the external power load and the storage battery is not in the fully charged state, the storage battery can be charged, and the surplus power in the fuel cell is stored in the storage battery. Further, when the battery is fully charged, the storage battery cannot be charged any more, and the surplus power is consumed by the power consumption means. In this way, even when the output of the fuel cell is used in a state where the change is as small as possible, it is possible to appropriately supply power according to the fluctuation of the external power load.

When the storage battery is in a fully charged state for a set time or longer, the electric power stored in the storage battery is consumed by the power consumption means. By consuming the electric power stored in the storage battery by the power consumption means in this way, the storage battery is released from the fully charged state.

Therefore, while the power can be appropriately supplied according to the fluctuation of the external power load, it is possible to prevent the fully charged state of the storage battery from continuing for a long time longer than the set time. Therefore, it is possible to provide a power supply device that can avoid the disadvantage that the storage battery is deteriorated at an early stage and can maintain the appropriate power storage performance for the storage battery for an extremely long period.

According to a second aspect of the present invention, in the first aspect, the power consuming means is composed of an electric heating device for heating a heat load, and the managing means is required to supply heat with the heat load. It is characterized in that the storage battery discharging process is executed only when it is determined whether or not the heat supply is necessary.

That is, since the power consumption means is composed of an electric heating device for heating the heat load, it is possible to effectively use the energy by effectively using the surplus power for heating the heat load. Since the storage battery discharge process is executed only when it is determined that heat supply is necessary under such a heat load, energy consumption such as wasteful heating when heat supply is not necessary under a heat load is performed. Useless consumption can be prevented in advance, and a suitable means for carrying out claim 1 can be obtained.

According to the present invention, the fuel cell for outputting the generated electric power to the outside and the surplus electric power of the fuel cell are stored and the stored electric power is output to the outside when the output of the fuel cell is insufficient. Storage battery, a power consumption means for consuming the surplus power, a charge state detection means for detecting the charge state of the storage battery, and a management means for managing the operating state of the power supply device, and the generated power of the fuel cell Is less than the load power of the external power load, the power stored in the storage battery is output to the outside, and if the power generated by the fuel cell is greater than the load power, the storage battery is not fully charged. In the power supply device configured to store the surplus power in the storage battery and to consume the surplus power in the power consuming unit when in the fully charged state, the management unit includes the storage battery. When the state determined to be the fully charged state continues for a set time or more, the output of the fuel cell is reduced to operate so as to consume the electric power stored in the storage battery. Characterize.

That is, if the generated power of the fuel cell is smaller than the external power load, the output of the fuel cell is insufficient, so the power stored in the storage battery is output to the outside. If the power generated by the fuel cell is larger than the external power load and the storage battery is not in the fully charged state, the storage battery can be charged, and the surplus power in the fuel cell is stored in the storage battery. Further, when the battery is fully charged, the storage battery cannot be charged any more, and the surplus power is consumed by the power consumption means. In this way, even when the output of the fuel cell is used in a state where the change is as small as possible, it is possible to appropriately supply power according to the fluctuation of the external power load.

When the state of the storage battery being fully charged continues for a set time or longer, the output of the fuel cell is reduced to operate to consume the electric power stored in the storage battery. That is, since the output of the fuel cell is insufficient for the external power load due to the decrease in the output of the fuel cell, the power stored in the storage battery is output to the outside. By consuming the electric power stored in the storage battery in this way, the storage battery is released from the fully charged state.

Therefore, it is possible to appropriately supply power according to the fluctuation of the external power load, but it is possible to prevent the fully charged state of the storage battery from continuing for a long time longer than the set time. Therefore, it is possible to provide a power supply device that can avoid the disadvantage that the storage battery is deteriorated at an early stage and can maintain the appropriate power storage performance for the storage battery for an extremely long period.

According to a fourth aspect, in the third aspect, a heat consuming device that is heated by the exhaust heat from the fuel cell is provided, and the managing means is provided by the exhaust heat from the fuel cell in the heat consuming device. It is characterized in that it is configured such that it is determined whether or not heating is necessary, and only when it is determined that heating is not necessary, the output of the fuel cell is reduced to operate.

Since the heat consuming device that is heated by the exhaust heat from the fuel cell is provided, the energy generated from the fuel cell can be effectively utilized, the energy efficiency can be improved, and the heat consuming Since the fuel cell is switched to the low-power operation state when heating is not required in the apparatus, it is possible to obtain a suitable means for carrying out claim 3 in a state where there is no disadvantage of lowering energy efficiency.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of a power supply device according to the present invention will be described below with reference to the drawings. FIG. 1 shows a power supply device according to the present invention. This power supply device boosts low-voltage DC power output from the fuel cell 1 to DC power corresponding to the voltage of a 200-V commercial AC power supply, and converts the boosted DC power into AC power. The DC power output from the fuel cell 1 is configured by including the inverter 3 and the like.
When the output power of the fuel cell 1 with respect to the external power load 4 is surplus, the surplus DC power is stored in the power storage device ES and is output to the external power load. When the output power of the fuel cell 1 is insufficient, the inverter 3 converts the DC power stored in the power storage device ES into AC power and outputs the AC power to the outside so as to make up for the shortage.

This power supply device is configured to supply the output power to the external power load 4, and the interconnection device 34 is used to supply the commercial power supply 35.
When the output power of the power supply device is insufficient for the external power load, the shortage is compensated by the commercial power supply. Further, as the external power load, general electric equipment which is assumed to be driven by a commercial AC power source in a general home or business is targeted.

The power supply device is also equipped with equipment for supplying fuel gas to the fuel cell 1. That is, as shown in FIG. 1, a fuel gas generation unit GS that generates a fuel gas containing hydrogen gas from a raw fuel and supplies the generated fuel gas to the fuel cell 1 and air as an oxygen-containing gas in the fuel cell 1. For supplying heat to the fuel cell 1, the heat exchanger 22 for preheating the cooling water to be supplied to the fuel cell 1 with the oxygen electrode side exhaust gas discharged from the fuel cell 1 through the exhaust gas passage 31, and the cooling water from the fuel cell 1 to the exhaust gas passage 32. A heat exchanger 23 and the like for preheating with the exhaust gas on the fuel electrode side discharged through is provided. The warm water discharged from the fuel cell 1 through the drainage channel 33 is used for heating the stored water stored in the hot water storage tank 42 as described later. That is, hot water storage tank 4
The stored water stored in 2 is circulated through the heat exchanger 44 by the pump 43, and the stored water passed through the heat exchanger 44 is heated by the heat of the hot water discharged through the drainage channel 33. It is configured to be heated. As the fuel cell, a solid polymer type using a solid polymer membrane as an electrolyte is used, but other than that, a phosphoric acid type using phosphoric acid as an electrolyte, a solid using a solid electrolyte as an electrolyte Various types such as electrolyte type can be used.

The hot water storage tank 42, which is separately provided as a heat load, is provided with an electric heating device 40 as a power consumption means for heating the stored hot water by consuming electric power. An electric power adjustment device 45 is provided that can change and adjust the electric power consumption of the heating device 40. The power adjusting device 45 has a configuration capable of changing and adjusting the amount of power consumed by the electric heating device 40 by, for example, a pulse width modulation method. The hot water stored in the hot water storage tank 42 is used for a bath or general hot water supply, and a heating operation is instructed by a setting device (not shown). 12 will be input.

The fuel gas generation unit GS includes a desulfurizer 24 for desulfurizing a hydrocarbon-based raw fuel gas such as natural gas,
A steam generator 25 that heats the supplied water to generate steam, and a raw fuel gas desulfurized by the desulfurizer 24 is converted into hydrogen gas and carbon monoxide gas by using the steam generated by the steam generator 25. A reformer 26 that performs a reforming process, and a shifter 2 that shifts the carbon monoxide gas in the reformed gas discharged from the reformer 26 to a carbon dioxide gas by using steam.
7 and a selective oxidizer 28 that selectively oxidizes carbon monoxide gas remaining in the metamorphic gas discharged from the metamorphic converter 27, and produces a fuel gas having a low carbon monoxide gas content. Is configured to. Reformer 26
Since the reforming reaction in is the endothermic reaction, the reformer 2
6 is provided with a burner 26b for giving heat of reaction, and the steam generator 25 is adapted to heat water by using exhaust heat of the burner 26 to generate steam.
When the natural gas containing methane gas as a main component is the raw fuel gas, the reformer 26 reforms the methane gas and steam to cause a reforming treatment gas containing hydrogen gas and carbon monoxide gas. To generate.

A switch SW1 for connecting and disconnecting a circuit is provided between the power storage device ES and the power supply path 7, and the switch SW1 is used when the operation abnormality occurs.
It functions as a disconnection switch 8 that disconnects between the power supply path 7 and the power supply path 7.

Next, the structure of the electricity storage device ES will be described. As shown in FIG. 2, the storage battery 5 is configured by connecting 96 unit battery cells C having an output voltage of several volts (for example, about 3 to 4 volts) in series.
In addition to charging and storing excess DC power, the DC power stored in the storage battery 5 can be converted into AC power by the inverter 3 and output to the outside. A lithium ion battery is used as the unit battery cell C. And this power storage device ES
, A power storage unit U is configured by using eight unit battery cells C as one unit, and is configured by 12 power storage units U in total, and each of these power storage units U belongs to the power storage unit U.
Each of the unit battery cells C is provided with a monitoring device KS that executes various processes described below while monitoring the voltage across the terminals, the internal temperature, and the like. These twelve monitoring devices KS constitute the charge state detecting means 6.

The monitoring device KS, as shown in FIG.
The voltage detection circuit 9 as the voltage detection means for detecting the terminal voltage of each of the eight unit battery cells C, the terminal voltage of the eight unit battery cells C is larger than that of the other unit battery cells C, and the discharge processing is performed. A digital signal is serially transmitted between the positive and negative terminals of the unit battery cell C, which is determined to be discharged, as a discharging means for short-circuiting via a resistor to discharge, and another monitoring device KS. An inter-device communication unit 11 that performs information communication, an upper-level communication unit 13 that performs information communication between the system controller 12 that manages the operation of the entire power supply device by serial transmission of digital signals, and each unit of the storage battery 5. Thermistor 14 for temperature detection
Temperature detection unit 15 for inputting detection information of the
On the basis of the detection information of the protection circuit operating unit 16 for operating the voltage detection circuit 9 and the voltage detection circuit 9, discharge is performed among the plurality of unit batteries C so that the positive-negative voltage of each of the plurality of unit batteries C becomes uniform or close to it. Discharge operation processing for determining what is to be done and discharging the determined unit battery by the discharge circuit 10, and necessary information based on information input from each unit is provided to another monitoring device KS or system controller 12.
The control circuit 17 and the like including a microcomputer for executing the processing for communicating with each other, the processing for activating the protection circuit operating unit 16 when an operation abnormality occurs, and the like.

Then, one group is composed of the four power storage units U, and one monitoring device KS in each group.
In a state where (hereinafter, referred to as a master monitoring device) manages the other three monitoring devices KS (hereinafter, referred to as slave monitoring devices), they mutually communicate with each other, the inter-device communication unit 11 and the communication line 18
Is communicatively connected via. Further, the master monitoring device KS in each of the groups and the system controller 12 are communicatively connected to each other via an inter-upper communication unit 13 and a communication line 19.

With this structure, each unit battery cell C
The monitoring information of the storage battery 5 such as the voltage detection information and the temperature detection information of the storage battery 5 is transmitted to the system controller 12, and the system controller 12 monitors the charging state, the temperature state, etc. of the storage battery 5 based on the information, and when the storage battery 5 is fully charged. If so, processing is performed to prohibit further charging, or to prohibit discharging if the state of charge is lower than the set value. That is, the system controller 12 determines whether or not the storage battery 5 is in the fully charged state based on the voltage detection information transmitted from each monitoring device KS, and if it is not in the fully charged state, the surplus power of the fuel cell is stored in the storage battery. 5, the electric heating device 40 is configured to consume the surplus power when the battery 5 is charged.

If the state in which it is determined that the storage battery 5 is in a fully charged state continues for a set time T4 or more even though the surplus power is consumed by the electric heating device 40, the storage battery 5 is charged. Electricity generated by electric heating device 4
It is configured to execute a battery discharge process that increases the power consumption of the electric heating device 40 so that the electric heating device 40 is consumed at zero. Further, it is judged whether or not the heat supply by the electric heating device 40 is necessary depending on whether or not the heating operation for heating a large amount of hot water in the hot water storage tank 42 to a high temperature is instructed, and the heat supply is necessary. The storage battery discharging process is executed only when it is determined that In addition, the power generation output of the fuel cell 1 is set to a standard value according to the external power load predicted in advance, and is configured to be output in a state fixed to the standard value.

The power consumption processing by the system controller 12 will be described with reference to the flowchart of FIG. If the storage battery discharging process as described later is not performed, the charge capacity of the entire storage battery 5 is obtained based on the detection information transmitted from each monitoring device KS, and the charge capacity becomes a maximum value or a value close to the maximum value and the saturated state is reached. It is determined whether or not the battery is fully charged (steps 1 and 2). That is, by continuing the operation of charging the storage battery 5 with the surplus power, as shown in FIG. 5, the charging capacity of the storage battery 5 increases, and the charging capacity is saturated at a maximum value or a value close to the maximum value. Fully charged state (state indicated by point Q in Fig. 5)
If it is detected, the electric heating device 40 executes surplus power consumption processing for consuming surplus power, and the timer counter is counted up from that point (steps 3 and 4). In this surplus power consumption processing, the following processing is executed. That is, the output voltage of the power supply path 7 when it is determined that the storage battery 5 is in the fully charged state is detected by the voltage detector 46, and the value is stored as the upper limit voltage value, and the surplus power consumption process is performed. In order to prevent the output voltage of the power supply path 7 detected by the voltage detector 46 from exceeding the upper limit voltage value, the electric heating device 40
The operation of the power adjusting device 45 is controlled to adjust the power consumption of

Then, the count value t of the timer counter
Exceeds the set value ts, it is determined that the storage battery 5 is in a fully charged state for a set time T4 or longer (step 5), and it is determined that heat supply by the electric heating device 40 is necessary. Then (step 6), a storage battery discharging process is executed to cause the electric heating device 40 to consume the electric power stored in the storage battery 5 (step 7). In the storage battery discharging process, the power adjusting device is set so that the output voltage of the power supply path 7 detected by the voltage detector 46 is set to a value lower than the upper limit voltage value by a predetermined amount. The operation of 45 is controlled. Then, the electric power stored in the storage battery 5 is output to the electric heating device 40. As a result, as shown in FIG. 5, the charging capacity of the storage battery 5 is reduced and the fully charged state is eliminated, and it is possible to prevent the fully charged state from continuing for a long time. When the storage battery discharging process is started, the process is continuously executed until the charge capacity of the storage battery 5 decreases from the value corresponding to the fully charged state to the charge capacity for stopping the discharge process, which is lower by the set amount. ,
When the charge capacity is reduced to the charge capacity for stopping the discharge process, the process is ended (step 1). When heat supply by the electric heating device 40 is not necessary, the storage battery discharging process is not performed (step 6). If it is not in the fully charged state, the timer counter is reset (step 8), and the storage battery 5 is charged with the surplus power of the fuel cell 1.

Second Embodiment Next, a second embodiment of the power supply device according to the present invention will be described. In this embodiment, except for the output form of the fuel cell and the configuration of the power consumption processing by the system controller, other configurations are the same as in the case of the first embodiment, so only the different configurations will be described. Descriptions of other configurations are omitted.

In the first embodiment, the power generation output of the fuel cell 1 is fixed to a standard value for use.
In this embodiment, the output of the fuel cell 1 is configured to be adjustable and adjustable, and the system controller uses the standard output mode in which the fuel cell 1 outputs the standard value and the fuel cell 1 has a larger output than the standard output mode. The output is reduced to a low output operation mode in which the output is low and the output is smaller than the external power load. Then, the system controller causes the electric heating device 40 to consume the electric power stored in the storage battery 5 when the state in which it is determined that the storage battery 5 is fully charged continues for a set time or more. It is configured to operate by reducing the output of 1. In addition, the system controller determines whether or not heating by the exhaust heat of the fuel cell is necessary in the heat exchanger 44 as a heat consuming device that is heated by the exhaust heat of the fuel cell from the required hot water supply demand. Then, only when it is determined that the heating is not necessary, the output of the fuel cell is reduced and the fuel cell is operated.

Based on the flow chart in FIG.
The power consumption process of the system controller 12 will be described. It is determined whether or not the low output operation mode is set, and if not set, the charge capacity of the entire storage battery 5 is calculated based on the detection information transmitted from each monitoring device KS, and the charge capacity is the maximum value or It is judged whether or not it is in a fully charged state in which the value becomes close to the saturated state (steps 10 and 11). That is, the surplus power is stored in the storage battery 5
As shown in FIG. 7, the charging capacity of the storage battery 5 is increased by continuing the operation of charging the battery to a full charge state in which the charging capacity is saturated at or near the maximum value (see FIG. 7). (State indicated by the point Q of 1) is detected, the excess power consumption process for consuming excess power in the electric heating device 40 is executed as in the process in the first embodiment, and the timer is started from that point. The counter is counted up (steps 12 and 13).

Then, the count value t of the timer counter
Exceeds the set value ts, and it is determined that the state in which the storage battery 5 is fully charged continues for the set time (T5) or more (step 14), and at this time, the exhaust heat from the fuel cell 1 as described above is discharged. It is determined whether or not there is a heat demand for the heat exchanger 44 that is heated in step S1, and if it is determined that there is no heat demand, the low output operation process is executed (steps 15 and 1).
6). If there is a heat demand on the heat exchanger 44, the low output operation processing is not performed. If the storage battery 5 is not fully charged, the timer counter is reset (step 1
7), the surplus power of the fuel cell 1 is charged in the storage battery 5. In the low power operation process, the fuel cell 1
Is switched to the low output operation mode and the operation is performed. As shown in FIG. 7, the electric power stored in the storage battery 5 is output to the external electric power load, and the fully charged state is canceled. That is, since the output of the fuel cell is insufficient for the external power load due to the decrease in the output of the fuel cell, the power stored in the storage battery is output to the outside, and the power stored in the storage battery is consumed. Of. Then, when the charge capacity of the storage battery 5 falls below the set value for releasing the low output, the low output operation process is terminated, and the operation mode of the fuel cell is returned from the low output operation mode to the standard output mode. It is configured.

[Other Embodiments] Other embodiments will be listed below.

(1) In the first embodiment, as the surplus power consumption processing, the output voltage of the power supply path 7 when it is determined that the storage battery 5 is in the fully charged state is stored as the upper limit voltage value. Then, the operation of the power adjustment device 45 is performed to adjust the power consumption of the electric heating device 40 so that the output voltage of the power supply path 7 detected by the voltage detector 46 does not exceed the upper limit voltage value. Although the configuration is controlled, the following configuration may be used instead of such a configuration. For example, a circuit that connects the power supply path 7 and the power storage device ES is provided with a current detector, and as the surplus power consumption process, the current detector monitors the value of the current flowing in the circuit, The operation of the power adjustment device 45 may be controlled to adjust the power consumption of the electric heating device 40 so that the charging current does not flow to the power storage device. Further, the electric power output from the boost converter 2 and the electric power input to the inverter 3 are respectively detected, and the electric power adjusting device is configured so that the difference between these electric powers is consumed by the electric heating device 40. It may be configured to control the operation of 45.

In the first embodiment, the power supply path 7 detected by the voltage detector 46 is used as the storage battery discharging process.
Of the electric power adjusting device 4 such that the output voltage of
Although the operation of No. 5 is controlled, it may be configured as follows instead of such a configuration. For example, a current detector is provided in a circuit that connects the power supply path 7 and the power storage device ES, and the discharge current from the power storage device detected by the current detector is set by a predetermined amount as the storage battery discharge process. The operation of the power adjustment device 45 may be controlled so that Further, the electric power output from the boost converter 2 and the electric power input to the inverter 3 are detected, and the electric power obtained by adding a set amount to the difference between these electric power is consumed by the electric heating device 40. As described above, the operation of the power adjusting device 45 may be controlled.

(2) In the first embodiment, the power consumption means is an electric heating device for heating a heat load,
The storage battery discharging process is executed only when it is determined that the heat supply by the heat load is necessary. However, instead of such a configuration, the storage battery 5 is in the fully charged state for a set time. When the above process is continued, the storage battery discharging process may be constantly executed. Further, the power consumption means is not limited to the electric heating device 40, and may be any device as long as it consumes power.

(3) In the second embodiment, it is judged whether or not heating by the exhaust heat from the fuel cell is necessary in the heat consuming device, and only when it is judged that the heating is not necessary, Although the fuel cell is configured to be operated with a reduced output, the output of the fuel cell is constantly reduced when the state in which the storage battery is in the fully charged state continues for a set time or longer, instead of such a configuration. You may comprise so that it may drive. Further, as the heat consuming device, the heat exchanger for storing hot water has been illustrated, but the heat consuming device is not limited to this, and another heat consuming device that utilizes the exhaust heat of the fuel cell may be used.

(4) In each of the above embodiments, as the power consuming means, for example, only the power consuming means b for consuming the power of the DC voltage boosted by the boost converter 2 in the configuration shown in FIG. 8 is illustrated. However, it is not limited to such a connection configuration, but the low-voltage DC voltage before being boosted by the boost converter 2, that is, the power consumption means a that consumes the output of the fuel cell as it is, or the AC power is converted by the inverter. The power consuming unit c that consumes the converted power may be used, or any one or more of these power consuming units may be used.

(5) In the above embodiment, the power adjusting device for the power consuming means may be configured to switch using various controls such as phase control, not limited to the pulse width modulation method.

(6) In each of the above embodiments, the commercial power source is connected to the system, and when the output power of the power source device is insufficient with respect to the external power load, the shortage can be compensated by the commercial power source. Although the configuration is possible, the configuration is not limited to such a configuration, and may be configured as an independent power supply device without being grid-connected to a commercial power supply.

.. (7) In each of the above-mentioned embodiments, the storage battery used is a lithium ion battery as a large number of unit batteries, but the present invention is not limited to this, and a lead storage battery, a nickel
Various things such as a cadmium storage battery and a nickel-hydrogen storage battery can be used.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a power supply device.

FIG. 2 illustrates a structure of a power storage device

FIG. 3 is a block diagram showing the configuration of a monitoring device.

FIG. 4 is a flowchart of a power consumption process of the first embodiment.

FIG. 5 is a timing chart of the first embodiment.

FIG. 6 is a flowchart of a power consumption process of the second embodiment.

FIG. 7 is a timing chart of the second embodiment.

FIG. 8 is a diagram showing a connection state of a power consumption means of another embodiment.

[Explanation of symbols]

1 fuel cell 5 storage battery 6 Charge state detection means 12 Management means 40 Power consumption means

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Claims (4)

[Claims] 1. A fuel cell for outputting the generated electric power to the outside, a storage battery for storing the surplus electric power of the fuel cell and outputting the stored electric power to the outside when the output of the fuel cell is insufficient. Power consumption means for consuming excess power,
A charge state detection means for detecting the charge state of the storage battery,
Management means for managing the operating state of the power supply device is provided, and if the generated power of the fuel cell is smaller than the load power of the external power load, the power stored in the storage battery is output to the outside,
If the generated power of the fuel cell is greater than the load power, the surplus power is stored in the storage battery if the storage battery is not in a fully charged state, and the surplus power is stored in the storage battery if the fully charged state. In the power supply device configured to consume the electric power stored in the storage battery, when the state in which the storage battery is in the fully charged state continues for a set time or more, the power consumption device is configured to consume the electric power stored in the storage battery. A power supply device configured to execute a storage battery discharging process to be consumed in. 2. The power consuming means is composed of an electric heating device for heating a heat load, and the managing means judges whether or not heat supply by the heat load is necessary, The power supply device according to claim 1, wherein the storage battery discharging process is executed only when it is determined that supply is necessary. 3. A fuel cell for outputting the generated power to the outside, a storage battery for storing the surplus power of the fuel cell and outputting the stored power to the outside when the output of the fuel cell is insufficient, Power consumption means for consuming excess power,
A charge state detection means for detecting the charge state of the storage battery,
Management means for managing the operating state of the power supply device is provided, and if the generated power of the fuel cell is smaller than the load power of the external power load, the power stored in the storage battery is output to the outside,
If the generated power of the fuel cell is greater than the load power, the surplus power is stored in the storage battery if the storage battery is not in a fully charged state, and the surplus power is stored in the storage battery if the fully charged state. When the state in which the management unit determines that the storage battery is in the fully charged state continues for a set time or longer, the power stored in the storage battery. A power supply device configured to operate by reducing the output of the fuel cell so as to consume the fuel. 4. A heat consuming device that is heated by exhaust heat from the fuel cell is provided, and the management means determines whether or not the heat consuming device needs to be heated by exhaust heat from the fuel cell. 4. The power supply device according to claim 3, wherein the power supply device is configured to be operated by reducing the output of the fuel cell only when it is determined that the heating is not necessary.