Power control system and hydrogen production equipment using the same

Abstract

To provide a power control system for reducing a burden on an electrolytic cell of a hydrogen manufacturing device to secure an amount of stable production of hydrogen, and hydrogen manufacturing facilities using the same.SOLUTION: A power control system includes: a first power converter for converting power supplied from a renewable energy generator into DC power X; a second power converter for converting power supplied from a commercial power system into DC power Y; a third power converter for converting total power of the DC power X and the DC power Y into DC power Z; and a control device for controlling the DC power Y to be a predetermined value.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a power control system and a hydrogen production facility using the same. [Background technology]

[0002] Japan has a low energy self-sufficiency rate, and is particularly dependent on imports for the majority of its fossil fuels. Fossil fuels emit carbon dioxide when used. For this reason, in recent years, the introduction of systems that generate electricity from renewable energy sources such as wind and solar power has been promoted as an energy supply source that takes environmental issues into consideration. In addition, hydrogen has been attracting attention as an energy supply source because it does not emit carbon dioxide when used.

[0003] The most widely used method for producing hydrogen is steam reforming of fossil fuels, but carbon dioxide is emitted during production. Furthermore, when hydrogen is produced by water electrolysis using thermal power generation, carbon dioxide is also emitted during production. Therefore, hydrogen production using renewable energy is being attempted as one method of producing hydrogen that reduces total carbon dioxide emissions. Renewable energy uses natural energy such as wind and solar power, and by its nature, is subject to large energy fluctuations.

[0004] In Patent Document 1, electrolysis cell stacks are connected in parallel via relays, and the amount of power supplied to each cell stack is increased or decreased to accommodate fluctuations in renewable energy. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-151561 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in Patent Document 1, a power source derived from renewable energy is directly connected to the hydrogen production device for operation. Although the power can be adjusted in response to fluctuations, an excessive burden is placed on the electrolysis cell of the hydrogen production device, which may accelerate deterioration of the electrolysis cell or shorten its lifespan.

[0007] Furthermore, while increasing the utilization rate of renewable energy reduces carbon dioxide emissions, the economic viability of renewable energy sources such as solar power generation is poor due to their poor energy efficiency. Conversely, increasing the utilization rate of hydrogen production facilities improves economic viability, but carbon dioxide emissions increase due to the use of electricity derived from thermal power plants. In this way, there is a trade-off between the utilization rate of renewable energy and the utilization rate of hydrogen production facilities.

[0008] In view of the above-mentioned circumstances, an object of the present invention is to provide a power control system that reduces the burden on an electrolytic cell of a hydrogen production device and ensures a stable amount of hydrogen production, and a hydrogen production facility using the same. [Means for solving the problem]

[0009] One aspect of the present invention made to solve the above problem is a power control system including a first power converter that converts power supplied from a renewable energy power generation device into DC power X, a second power converter that converts power supplied from a commercial power system into DC power Y, a third power converter that converts a total power of the DC power X and the DC power Y into DC power Z, and a control device that controls the DC power Y to be a predetermined value.

[0010] In the power control system, the first power converter converts the power supplied from the renewable energy power generation device into the DC power X. Meanwhile, the second power converter converts the power supplied from the commercial power system into the DC power Y. The control device controls the DC power Y to a predetermined value. By controlling the DC power Y to a predetermined value in this manner, the control device can suppress power fluctuations compared to the case where only power is supplied from the renewable energy power generation device.

[0011] It is preferable that the first power converter converts the power supplied from the renewable energy power generation device into the DC power X of a predetermined voltage, and the control device detects the DC power X and controls the current of the second power converter so that the power supplied from the commercial power system becomes the DC power Y of the predetermined voltage. In this way, since the control device converts the power supplied from the renewable energy power generation device and the power supplied from the commercial power system to a predetermined voltage, both powers can be summed.

[0012] It is preferable to arbitrarily set the value of the DC power Z. In this way, by arbitrarily setting the value of the DC power Z, it is possible to employ hydrogen production devices requiring different amounts of electric power.

[0013] It is preferable that the control device detects the DC power X and controls the DC power Y to a predetermined value, the predetermined value being a value obtained by subtracting the value of the DC power X from the value of the DC power Z. In this manner, the control device controls the DC power Y to a value obtained by subtracting the value of the DC power X from the value of the DC power Z, thereby making it possible to compensate for a shortage with the DC power Y in accordance with a fluctuation in the DC power X so that the total power becomes the DC power Z. As a result, it is possible to maintain the total power (DC power Z) constant.

[0014] It is preferable that the third power converter is configured to supply the DC power Z to a hydrogen production device, and the value of the DC power Z is set according to the remaining amount of hydrogen in a storage tank that stores the hydrogen produced by the hydrogen production device. In this way, by setting the value of the DC power Z according to the remaining amount of hydrogen in the storage tank, the required amount of hydrogen can be appropriately produced.

[0015] It is preferable that the storage tank has a pressure gauge that measures the remaining amount of hydrogen. In this way, by having the storage tank have a pressure gauge that measures the remaining amount of hydrogen, the remaining amount of hydrogen can be accurately detected.

[0016] It is preferable that the DC power Z is greater than the DC power required to produce hydrogen for regeneration in a dehumidifier mounted on the hydrogen production device. By making the DC power Z greater than the DC power required to produce hydrogen for regeneration in the dehumidifier in this manner, hydrogen for regeneration in the dehumidifier can be secured, and hydrogen derived from renewable energy can be stably supplied.

[0017] It is preferable that the control device controls the DC power Y to a predetermined value, and the predetermined value is a constant value. By controlling the DC power Y to a constant value in this manner, the DC power Z includes the DC power Y from the commercial power system that is maintained at a constant value in addition to the DC power X from the renewable energy power generation device, so that the fluctuation is relatively small compared to the case where the DC power Z supplied to the hydrogen production device is only power from the renewable energy power generation device. Moreover, a constant value of power can be stably secured regardless of fluctuations in the DC power X.

[0018] It is preferable that the third power converter is configured to supply the DC power Z to a hydrogen production device, and the control device allocates all or a part of the DC power Z to DC power required to produce hydrogen for regeneration in a dehumidifier mounted on the hydrogen production device. By allocating the DC power Z to the DC power required to produce hydrogen for regeneration in the dehumidifier in this manner, hydrogen for regeneration in the dehumidifier can be secured, and hydrogen derived from renewable energy can be stably supplied.

[0019] It is preferable that a control device of the power control system detects the DC power X, and controls the DC power Y by switching between an operation pattern A in which the DC power Y is controlled to a value obtained by subtracting the value of the DC power X from the value of the DC power Z, and an operation pattern B in which the DC power Y is controlled to a constant value. By switching between the two operation patterns in this way, the power applied to the electrolytic cell of the hydrogen production device can be kept constant as necessary, thereby reducing the burden on the electrolytic cell. Thus, the hydrogen production device can stably produce hydrogen.

[0020] It is preferable that the first power converter is a DC / DC converter or an AC / DC converter, the second power converter is an AC / DC converter, and the third power converter is a DC / DC converter. In this way, by using the first power converter as a DC / DC converter or an AC / DC converter, the power supplied from the renewable energy power generation device can be converted into DC power X even if it is AC power or DC power.

[0021] Another aspect of the present invention is a hydrogen production facility including the above-mentioned power control system, the hydrogen production device, and the storage tank for storing hydrogen produced by the hydrogen production device.

[0022] Since the hydrogen production facility utilizes the power control system described above, even if renewable energy is used, power with suppressed fluctuations can be supplied to the hydrogen production facility. The hydrogen production facility can reduce the burden on the electrolytic cells of the hydrogen production device and produce hydrogen stably. Furthermore, the hydrogen production facility utilization rate can be improved without excessively reducing the renewable energy utilization rate.

[0023] "Renewable energy" refers to energy sources that are constantly regenerated or semi-permanently supplied through natural activities such as sunlight, solar heat, hydroelectric power, wind power, and biomass, and can be reused or supplied inexhaustibly. "Renewable energy power generation equipment" refers to equipment that generates electricity using these energies. Effect of the Invention

[0024] As described above, the present invention can suppress fluctuations in power compared to a case where only power is supplied from a renewable energy power generation device. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic diagram showing a power control system according to one embodiment of the present invention and a hydrogen production facility using the power control system. [Diagram 2] FIG. 2 is a conceptual diagram showing an operation pattern A in which the fluctuation of DC power X is compensated for by DC power Y. In FIG. [Diagram 3] FIG. 3 is a diagram showing the operation data of the hydrogen production device when the DC power Z is 100%. [Figure 4] FIG. 4 is a conceptual diagram showing an operation pattern B in which DC power Y is controlled to a constant value regardless of fluctuations in DC power X. [Diagram 5] FIG. 5 is a diagram showing operation data of the hydrogen production device when the value of the DC power Y is fixed at 5% of the rated value. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

[0027] (Embodiment 1) FIG. 1 is a schematic configuration diagram showing the power control system of the first embodiment and a hydrogen production facility as an example to which the power control system is applied.

[0028] Hereinafter, a hydrogen production facility according to an embodiment of the present invention will be described in detail, and the power control system therein will be described in detail.

[0029] [composition] As shown in Fig. 1, the hydrogen production facility 200 includes a power control system 100, a hydrogen production device 7, a dehumidifier 10 mounted in the hydrogen production device 7, a storage tank 8 for storing the produced hydrogen H, and a pressure gauge 9 attached to the storage tank 8. The power control system 100 controls the power P R A first power converter 2 converts the power from the commercial power grid 3 into DC power X. C The system comprises a second power converter 4 that converts the total power of DC power X and DC power Y into DC power Y, a third power converter 5 that converts the total power of DC power X and DC power Y into DC power Z required to drive a hydrogen production device 7, and a control device 6 that detects the voltage of the first power converter 2 and controls the second power converter 4 to keep the voltage from the commercial power system 3 constant and adjust the current. In addition, the control device 6 detects the remaining amount of hydrogen in the storage tank 8 from the value of a pressure gauge 9 attached to the storage tank 8, and determines the value of DC power Z required to drive the hydrogen production device 7. Hydrogen produced by the hydrogen production device 7 is dehumidified through a dehumidifier 10. These elements will be explained below in the order of the flow of power.

[0030] <Renewable energy power generation equipment> The renewable energy power generation device 1 generates power by utilizing natural energy and outputs DC power or AC power. As the renewable energy power generation device 1, for example, well-known renewable energy power generation devices such as a solar power generation device, a geothermal power generation device, a wind power generation device, a tidal power generation device, a biomass power generation device, or the like can be appropriately used.

[0031] <Commercial power system> The commercial power system 3 is a stable power source that compensates for the power obtained by subtracting the value of DC power X from the value of DC power Z. The commercial power system 3 is not particularly limited as long as it can supply stable power, and for example, power generated by thermal power generation, nuclear power generation, etc. can be used.

[0032] <First power converter> The first power converter 2 converts the DC power or AC power output from the renewable energy power generation device 1 into DC power X of a predetermined voltage. This predetermined voltage is set appropriately according to the voltage to be supplied to the hydrogen production device 7. The first power converter 2 may be, for example, a DC / DC converter or an AC / DC converter. The DC / DC converter or AC / DC converter is not particularly limited as long as it can convert the DC power or AC power output from the renewable energy power generation device 1 into DC power, and a commercially available DC / DC converter, AC / DC converter, power conditioner, or the like may be appropriately adopted.

[0033] <Second power converter> The second power converter 4 converts AC power output from the commercial power system 3 into DC power Y of a predetermined voltage. An example of the second power converter 4 is an AC / DC converter. The AC / DC converter may be the same as that of the first power converter 2.

[0034] <Third power converter> The third power converter 5 converts the total power of the DC power X and the DC power Y into DC power Z. An example of the third power converter 5 is a DC / DC converter. The DC / DC converter may be the same as that of the first power converter 2.

[0035] <Hydrogen production equipment> The hydrogen production device 7 is driven by DC power Z to produce hydrogen. The hydrogen production device 7 may be equipped with a device for generating hydrogen by electrolysis, but is not particularly limited as long as it can produce a predetermined amount of hydrogen, and an existing hydrogen production device or the like may be used.

[0036] <Dehumidifier> The dehumidifier 10 is a device that removes moisture contained in the produced hydrogen. The dehumidifier 10 is composed of, for example, an adsorption tower that includes an adsorbent that absorbs moisture in the hydrogen. The hydrogen production device 7 generates hydrogen by electrolysis (electrolysis of water), but the generated hydrogen usually contains a large amount of moisture. A dehumidifier 10 is provided to remove the moisture contained in the generated hydrogen. The hydrogen production device 7 includes a water electrolysis device (not shown) and two dehumidifiers 10 (not shown). The two dehumidifiers 10 have the same structure and include an adsorbent capable of adsorbing moisture and releasing the adsorbed moisture by heating to regenerate the moisture adsorption performance, and a heater (not shown) for heating the adsorbent.

[0037] The hydrogen production device 7 has a flow path (piping) that guides the hydrogen generated in the water electrolysis device to a storage tank 8, and two dehumidifiers 10 are arranged in parallel along the flow path. A three-way valve is arranged on each of the upstream (inlet) and downstream (outlet) sides of the two dehumidifiers 10 arranged in parallel, and the upstream three-way valve (hereinafter also referred to as the "dehumidifier switching valve") is connected to the flow path from the water electrolysis device, one dehumidifier 10, and the flow path to the other dehumidifier 10, while the downstream three-way valve (hereinafter also referred to as the "dehumidifier regeneration switching valve") is connected to the flow paths from the water electrolysis device, one dehumidifier 10, the other dehumidifier 10, and the storage tank 8, respectively.

[0038] In addition, a three-way valve (hereinafter also referred to as a "valve that opens to the atmosphere from the one dehumidifier 10 side") is provided in the middle of the flow path connecting the dehumidifier switching valve and the other dehumidifier 10, and a three-way valve (hereinafter also referred to as a "valve that opens to the atmosphere from the other dehumidifier 10 side") is provided in the middle of the flow path connecting the dehumidifier switching valve and the other dehumidifier 10, allowing the flow path to be opened to the atmosphere.

[0039] In this embodiment, the system is configured so that a cycle operation can be performed in which the two dehumidifiers 10 are used alternately.

[0040] To explain the above in more detail, in this embodiment, the hydrogen flow paths of the dehumidifier switching valve and the dehumidifier regeneration switching valve are adjusted so that hydrogen generated from the water electrolysis device is supplied to one of the dehumidifiers 10, and dry hydrogen that has passed through the one of the dehumidifiers 10 is supplied to the storage tank 8 as product gas.

[0041] Furthermore, after sufficient moisture has been adsorbed by the adsorbent in one of the dehumidifiers 10, the supply destination of the generated hydrogen is switched to the other dehumidifier 10 by the dehumidifier switching valve, and the dry hydrogen that has passed through the other dehumidifier 10 is supplied to the storage tank 8 as product gas. In other words, by switching the flow path of the generated hydrogen from one dehumidifier 10 to the other dehumidifier 10, one dehumidifier 10 is configured to operate in a regeneration mode in which the adsorbent is regenerated, and the other dehumidifier 10 is configured to operate in a dehumidification mode in which hydrogen containing moisture is dehumidified. In addition, rather than using the entire amount of dry hydrogen as product gas in the dehumidification mode of the other dehumidifier 10, a portion of the dry hydrogen can be used as regeneration hydrogen for regenerating the adsorbent in the regeneration mode of one dehumidifier 10. That is, while energizing the heater of the one of the dehumidifiers 10 to heat the adsorbent in the one of the dehumidifiers 10, the hydrogen for regeneration is introduced from the downstream side of the one of the dehumidifiers 10 through the dehumidifier regeneration switching valve, and the moisture desorbed from the adsorbent is entrained in the hydrogen for regeneration, and is released to the outside of the system as moist hydrogen (exhaust gas) from a valve opening to the atmosphere from the one of the dehumidifiers 10 side. In this embodiment, by securing the electricity required to operate the dehumidifier 10, hydrogen for regeneration of the dehumidifier 10 can be secured, and hydrogen derived from renewable energy can be supplied stably.

[0042] <Storage tank> The storage tank 8 can store hydrogen produced by the hydrogen production device 7. The storage tank 8 is not particularly limited as long as it can store hydrogen, and for example, an existing hydrogen storage tank can be used.

[0043] <Pressure gauge> The pressure gauge 9 detects the pressure inside the storage tank 8. The remaining amount of hydrogen is expressed as the ratio of the measured pressure to the pressure when the remaining amount of hydrogen in the storage tank 8 is full. There are no particular limitations on the pressure gauge 9 as long as it can measure the pressure inside the storage tank 8, and any existing pressure gauge can be used.

[0044] <Control device> The control device 6 detects the DC power X output from the first power converter 2 and controls the current of the second power converter 4 so that the value obtained by subtracting the value of the DC power X from the value of the DC power Z becomes the value of the DC power Y. The detection of the DC power is performed using a wattmeter (not shown), a voltmeter (not shown), or an ammeter (not shown). The control device 6 sets the value of the DC power Z when calculating the value of the DC power Y based on the pressure of the storage tank 8 detected by the pressure gauge 9. Furthermore, in this embodiment, the control device 6 controls the operations of the first power converter 2, the second power converter 4, and the third power converter 5 so that the first power converter 2, the second power converter 4, and the third power converter 5 operate as described above. The control device 6 is composed of an arithmetic processing device such as a microcontroller or a microprocessor. The operations of the first power converter 2 and the third power converter 5 may be controlled by another control device. The control device 6 controls the DC power Y in accordance with the operation pattern A. That is, the control device 6 controls the DC power Y to be a value obtained by subtracting the value of the DC power X from the value of the DC power Z. That is, the control device 6 controls the DC power Y to satisfy the following formula (1). Y = ZX (1) FIG. 2 is a conceptual diagram of the operation pattern A. FIG. 2 shows a case where a solar power generation device is used as the renewable energy power generation device 1. The vertical axis indicates power (kW), and the horizontal axis indicates time. The white area indicated by reference character X indicates the power (DC power X) from the renewable energy power generation device 1, and the shaded area indicated by reference character Y indicates the power (DC power Y) from the commercial power system. Referring to FIG. 2, the power (DC power X) from the renewable energy power generation device 1 starts to be supplied around 7:00 in the morning, gradually increases thereafter, peaks around noon, and then gradually decreases, ending around 5:00 in the evening. In this way, the power (DC power X) from the renewable energy power generation device 1 fluctuates greatly. However, power (DC power Y) from the commercial power system is supplied to make up for (compensate for) this fluctuation, so that the total power of both (DC power Z) is maintained constant. The DC power Z is greater than the DC power required to produce hydrogen for regeneration by the dehumidifier 10 mounted on the hydrogen production device 7.

[0045] [Operation] Next, the operation of the hydrogen production facility 200 and the power control system 100 configured as described above will be described in detail. First, the first power converter 2 converts the power supplied from the renewable energy power generation device 1 into DC power X. Meanwhile, the second power converter 4 converts the power supplied from the commercial power system 3 into DC power Y. The control device 6 detects the converted DC power X and controls the current value of DC power Y so that the value of DC power Y becomes a value obtained by subtracting the value of DC power X from the value of DC power Z. By controlling the DC power Y in this manner, the total power becomes DC power Z. In this case, the DC power Z is larger than the DC power required to produce hydrogen for regeneration in the dehumidifier 10 mounted on the hydrogen production device 7. This DC power Z is supplied to the hydrogen production device 7 via the third power converter 5. The hydrogen production device 7 produces hydrogen by electrolysis using this DC power Z. The produced hydrogen is stored in a storage tank 8.

[0046] According to the above-mentioned embodiment 1, the power applied to the electrolytic cell of the hydrogen production device 7 is kept constant, thereby reducing the burden on the electrolytic cell and enabling the hydrogen production device 7 to stably produce hydrogen. Furthermore, the shortfall in the power supplied from the renewable energy power generation device 1 relative to the DC power Z required to drive the hydrogen production device 7 is made up for by the power supplied from the commercial power grid 3, so the utilization rate of the hydrogen production facility 200 can be improved without excessively reducing the renewable energy utilization rate. Furthermore, since the value of DC power Z is set according to the amount of hydrogen remaining in storage tank 8, the required amount of hydrogen can be appropriately produced. Furthermore, since the DC power Z is greater than the DC power required to produce hydrogen for regeneration of the dehumidifier 10 mounted on the hydrogen production device 7, the DC power required to operate the dehumidifier 10 can be allocated to the dehumidifier 10. As a result, hydrogen for regenerating the dehumidifier 10 can be secured, and a stable supply of regeneration gas can be achieved.

[0047] [Example 1] An example of a hydrogen production facility according to one embodiment of the present invention will be described in detail below, but the present invention should not be construed as being limited based on the description of this example.

[0048] The hydrogen production facility used was the hydrogen production facility 200 shown in Fig. 1. The main components of this hydrogen production facility 200 will be described below.

[0049] A solar power generation device was used as the renewable energy power generation device. The solar power generation device receives sunlight, generates electricity, and outputs DC power.

[0050] The commercial power system 3 used had a rated voltage of 440V and a rated capacity of 225kVA.

[0051] A DC / DC converter with a rated voltage of 500V and a rated capacity of 100kW was used as the first power converter 2. A voltage detector (not shown) is attached to the first power converter 2, and the first power converter 2 converts the DC power output from the renewable energy power generation device 1 into DC power X, and the voltage value of the DC power X output from the first power converter 2 is detected by the voltage detector.

[0052] As the second power converter 4, an AC / DC converter was used with a DC output having a rated voltage of 750V and a rated capacity of 210kW, and an AC output having a rated voltage of 440V and a rated capacity of 100kVA.

[0053] As the third power converter 5, a DC / DC converter with a rated voltage of 300V and a rated output current of 900A was used.

[0054] An appropriate arithmetic processing device having a circuit / control method based on a voltage type / current control method was used as the control device 6. The arithmetic processing device had a computer with a CPU, memory, etc., and performed various calculations to compensate for power fluctuations based on the power generation output signal and output control commands.

[0055] A water electrolysis type high purity hydrogen generator (SH20D manufactured by Kobe Steel Environmental Solutions) was used as the hydrogen production device 7. Hydrogen gas supply amount: 20 Nm 3 / h, hydrogen supply pressure: 0.82MPaG skid-mounted type was used. was used.

[0056] The dehumidifier 10 used was one that performs dehumidification processing using an adsorbent.

[0057] Storage tank 8 is made of SCM435 (chrome molybdenum steel) and has an internal volume of 0.15 m 3 A design pressure of 50 MPa was used.

[0058] As the pressure gauge 9, a commercially available pressure gauge capable of measuring the remaining amount of hydrogen in the storage tank 8 was used.

[0059] 3 shows the operating data of the hydrogen production device 7 when the DC power Z in the hydrogen production facility 200 is 100%. "When the DC power Z is 100%" refers to a state in which the hydrogen production device maintains the power (DC power Z) required to produce a specified amount of hydrogen. In Fig. 3, the vertical axis indicates power (%), and the horizontal axis indicates the elapsed time (minutes) from the start of operation. The zigzag line connecting the circles indicates DC power Z supplied to the hydrogen production device 7, the zigzag line connecting the squares indicates DC power X from the renewable energy power generation device 1, and the zigzag line connecting the triangles indicates DC power Y from the commercial power system 3. The zigzag line indicates actual measurement data. The plots of circles, triangles, and squares indicate representative positions. The reason for this is to distinguish these three lines of actual measurement data from one another. 3, the DC power X from the renewable energy power generation device 1 changed over time from the start of operation. However, the DC power Y from the commercial power grid 3 changed so as to compensate for the fluctuations in the DC power X through the control of the second power converter 4 by the control device 6. As a result, the DC power Z supplied to the hydrogen production device 7 was maintained at a constant value of 100%. From the above, the above-mentioned effects of the operation pattern A of the hydrogen production facility 200 and the power control system 100 of this embodiment have been demonstrated.

[0060] (Embodiment 2) In the second embodiment, the control device 6 controls the DC power Y to be a constant value. That is, the control device 6 controls the DC power Y to be in operation pattern B. The rest of the configuration is the same as in the first embodiment.

[0061] FIG. 4 is a conceptual diagram of operation pattern B. FIG. 4 shows a case where a photovoltaic power generation device is used as in operation pattern A. The vertical axis indicates power (kW), and the horizontal axis indicates time. The white area indicated by reference character X indicates power (DC power X) from the renewable energy power generation device 1, and the hatched area indicated by reference character Y indicates power (DC power Y) from the commercial power system. As shown in FIG. 4, the power (DC power X) from the renewable energy power generation device 1 fluctuates greatly. On the other hand, a constant power (DC power Y) is supplied from the commercial power system. As a result, the total power of both (DC power Z) becomes power having a waveform in which a constant value of base load power (DC power Y) is superimposed with a mountain-shaped changing power (DC power X).

[0062] Next, the operation of the hydrogen production facility 200 and the power control system 100 in the second embodiment thus configured will be described in detail. A first power converter 2 converts the power supplied from a renewable energy power generation device 1 into DC power X. Meanwhile, a second power converter 4 converts the power supplied from a commercial power system 3 into DC power Y. A control device 6 controls the current value of DC power Y so that DC power Y becomes a constant value.

[0063] According to the above-mentioned embodiment 2, the power (DC power Z) supplied to the hydrogen production device 7 includes the power (DC power X) from the renewable energy power generation device 1 as well as the power (DC power Y) from the commercial power system that is maintained at a constant value, so that the fluctuation is relatively small compared to the case where the power (DC power Z) supplied to the hydrogen production device 7 is only the power from the renewable energy power generation device 1. Moreover, a constant value of power can be stably secured regardless of the fluctuation of the DC power X. Moreover, since a constant DC power Y is secured, the control device 6 can allocate all or a part of the DC power Z to the DC power required to produce hydrogen for regeneration of the dehumidifier 10 mounted on the hydrogen production device 7. As a result, hydrogen for dehumidifier regeneration can be secured, and a stable regeneration gas can be supplied.

[0064] [Example 2] Example 2 of the hydrogen production equipment according to one embodiment of the present invention will be described in detail below, but the present invention should not be construed as being limited based on the description of this example.

[0065] The hydrogen production equipment used was the same as that used in Example 1.

[0066] 5 shows the operating data of the hydrogen production device 7 when the DC power Y in the hydrogen production facility 200 is rated at 5%. "When the DC power Y is rated at 5%" means that the power supply amount of the DC power Y is 5% when the power required for the hydrogen production device to produce a specified amount of hydrogen is taken as 100%. In FIG. 5, the vertical axis indicates power (%), and the horizontal axis indicates the elapsed time (minutes) from the start of operation. The zigzag line connecting the circles indicates the DC power Z supplied to the hydrogen production device 7, the zigzag line connecting the squares indicates the DC power X from the renewable energy power generation device 1, and the straight line connecting the triangles indicates the DC power Y from the commercial power system 3. The zigzag line and the straight line indicate the actual measured data. The plots of the circles, triangles, and squares indicate representative positions. The reason for this is the same as in FIG. 3 described above. FIG. 5 shows a state in which solar power generation is taking place during the day. And it shows a state in which the weather suddenly changes from sunny to dark due to rain or the like around 330 minutes after the start of operation, and the power from the solar power generation device becomes substantially zero. 5, DC power Y from the commercial power grid 3 supplied 5% of the rated power regardless of fluctuations in the power supplied by DC power X. Although DC power X from the renewable energy power generation device 1 fell below the rated 5% power just before 330 minutes had elapsed, DC power Z did not fall below the rated 5% power due to the power compensation from DC power Y. As a result, the state in which DC power Z supplied more than 5% of the rated power, which is the power necessary to secure hydrogen for regenerating the dehumidifier, was maintained. From the above, the above-mentioned effects of the operation pattern B of the hydrogen production facility 200 and the power control system 100 of this embodiment have been demonstrated.

[0067] (Embodiment 3) In the third embodiment, the control device 6 detects the DC power X, and controls the DC power Y by switching between an operation pattern A in which the DC power Y is controlled to a value obtained by subtracting the value of the DC power X from the value of the DC power Z, and an operation pattern B in which the DC power Y is controlled to a constant value. The rest of the configuration is the same as that of the first embodiment.

[0068] According to the third embodiment, by switching between operation pattern A and operation pattern B as necessary, the power applied to the electrolytic cell of the hydrogen production device can be kept constant, reducing the burden on the electrolytic cell, and by keeping the power constant, the hydrogen production device can stably produce hydrogen.

[0069] (Other embodiments) The above-mentioned embodiment does not limit the configuration of the present invention. Therefore, the above-mentioned embodiment may omit, replace, or add the configuration of each part of the above-mentioned embodiment based on the description in this specification and common technical knowledge, and it is understood that all of these are within the scope of the present invention.

[0070] In the above embodiment, the case has been described where power is compensated by converting AC power from a commercial power system into DC power Y, but power may also be compensated by converting DC power from a storage battery or the like into DC power Y. In this case, it is preferable to use a second power converter that converts DC power from a storage battery or the like into DC power Y, which is capable of converting DC power into a predetermined DC power, such as a DC / DC converter.

[0071] In the above, the case where power is compensated by converting DC power from a storage battery or the like into DC power Y has been described. However, for example, a configuration may be adopted in which power from a storage battery or the like is directly used to compensate for DC power X. [Industrial Applicability]

[0072] By using the power control system and hydrogen production facility of the present invention, it is possible to reduce the burden on the electrolytic cell of the hydrogen production device and produce hydrogen stably. Therefore, the present invention can be suitably used for producing hydrogen using a device with fluctuating power such as a renewable energy power generation device as a power source. [Explanation of symbols]

[0073] 1. Renewable energy power generation equipment 2 First power converter 3 Commercial power system 4 Second Power Converter 5. Third Power Converter 6. Control device 7 Hydrogen production equipment 8. Storage Tanks 9. Pressure Gauge 10 Dehumidifier 100 Power Control System 200 Hydrogen production facility

Claims

1. A first power converter that converts power supplied from a renewable energy power generation device that outputs DC power or AC power that changes over time into DC power X; a second power converter that converts power supplied from a commercial power system into DC power Y; a third power converter that converts a total power of the DC power X and the DC power Y into DC power Z; a control device that controls the DC power Y to be a predetermined value; Equipped with the third power converter is configured to supply DC power Z to the hydrogen production apparatus, A power control system in which the DC power Z is maintained constant from the start of power supply from the renewable energy power generation device to the end of power supply.

2. A first power converter that converts power supplied from a renewable energy power generation device that outputs DC power or AC power that changes over time into DC power X; a second power converter that converts power supplied from a commercial power system into DC power Y; a third power converter that converts a total power of the DC power X and the DC power Y into DC power Z; a control device that controls the DC power Y to be a predetermined value; Equipped with the third power converter is configured to supply DC power Z to the hydrogen production apparatus, The DC power Y is constantly supplied from the renewable energy power generation device from the start of power supply to the end of power supply, The control device detects the DC power X, and controls the DC power Y in accordance with a control pattern A in which the control device controls the DC power Y to a value obtained by subtracting the value of the DC power X from the value of the DC power Z.

3. A first power converter that converts power supplied from a renewable energy power generation device that outputs DC power or AC power that changes over time into DC power X; a second power converter that converts power supplied from a commercial power system into DC power Y; a third power converter that converts a total power of the DC power X and the DC power Y into DC power Z; a control device that controls the DC power Y to be a predetermined value; Equipped with the third power converter is configured to supply DC power Z to the hydrogen production apparatus, A power control system in which the predetermined value is a constant value.

4. A first power converter that converts power supplied from a renewable energy power generation device that outputs DC power or AC power that changes over time into DC power X; a second power converter that converts power supplied from a commercial power system into DC power Y; a third power converter that converts a total power of the DC power X and the DC power Y into DC power Z; a control device that controls the DC power Y to be a predetermined value; Equipped with the third power converter is configured to supply DC power Z to the hydrogen production apparatus, an operation pattern A in which the control device detects the DC power X and controls the DC power Y to a value obtained by subtracting the value of the DC power X from the value of the DC power Z; and an operation pattern B in which the DC power Y is controlled to be a constant value, thereby controlling the DC power Y.

5. the control device detects the DC power X and controls the DC power Y to be the predetermined value; 2. The power control system according to claim 1, wherein the predetermined value is a value obtained by subtracting the value of the DC power X from the value of the DC power Z.

6. 6. The power control system according to claim 5, wherein the value of the DC power Z is set in accordance with the amount of hydrogen remaining in a storage tank that stores hydrogen produced by the hydrogen production device.

7. 7. The power control system according to claim 1, 5, or 6, wherein the first power converter is configured to convert power supplied from the renewable energy power generation device into the DC power X of a predetermined voltage, and the control device is configured to detect the DC power X and control a current of the second power converter so that power supplied from the commercial power system becomes the DC power Y of the predetermined voltage.

8. 8. The power control system according to claim 1, wherein the value of the DC power Z is set arbitrarily.

9. the first power converter is a DC / DC converter or an AC / DC converter, the second power converter is an AC / DC converter; 9. The power control system according to claim 1, wherein the third power converter is a DC / DC converter.

10. A power control system according to any one of claims 1 to 9; A hydrogen production device; A storage tank for storing hydrogen produced by the hydrogen production device; Hydrogen production facility equipped with:

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