SYSTEM FOR PRODUCING HYDROGEN FROM RENEWABLE ENERGY AND CONTROL METHOD THEREOF

Abstract

The present disclosure relates to a system for producing hydrogen from renewable energy and a control method thereof. The system includes a renewable-energy-based power generation system, a primary hydrogen production system, a secondary hydrogen production system, and a controller. An output end of the renewable-energy-based power generation system is connected to the primary hydrogen production system and the secondary hydrogen production system via an electrical conversion device. A capacity of the primary hydrogen production system is greater than or equal to a capacity of the secondary hydrogen production system. The controller is configured to monitor an output electrical performance parameter of the renewable-energy-based power generation system in real time, and control turn on and turn off of the primary hydrogen production system and the secondary hydrogen production system.

Claims

1. A system for producing hydrogen from renewable energy, comprising a renewable-energy-based power generation system, a primary hydrogen production system, a secondary hydrogen production system, and a controller, wherein an output end of the renewable-energy-based power generation system is connected to the primary hydrogen production system and the secondary hydrogen production system via an electrical conversion device; a monitoring end of the controller is connected to the output end of the renewable-energy-based power generation system, and a control end of the controller is connected to the electrical conversion device; and a capacity of the primary hydrogen production system is greater than or equal to a capacity of the secondary hydrogen production system.

2. The system for producing hydrogen from renewable energy according to claim 1, wherein the electrical conversion device comprises a primary electrical converter and a secondary electrical converter, wherein the output end of the renewable-energy-based power generation system is connected to a direct current (DC) bus, the DC bus is connected to a power supply end of the primary hydrogen production system via the primary electrical converter, the DC bus is connected to a power supply end of the secondary hydrogen production system via the secondary electrical converter, and the control end of the controller is connected to the primary electrical converter and the secondary electrical converter.

3. The system for producing hydrogen from renewable energy according to claim 2, wherein the renewable-energy-based power generation system comprises a photovoltaic array or a wind power generator, the primary hydrogen production system comprises one primary electrolytic cell for hydrogen production, and the secondary hydrogen production system comprises one or more secondary electrolytic cells for hydrogen production.

4. The system for producing hydrogen from renewable energy according to claim 3, further comprising an energy storage unit or grid, wherein the energy storage unit or grid is connected to the DC bus via a bi-directional electrical converter included m the electrical conversion device, and the control end of the controller is connected to the bi-directional electrical converter.

5. The system for producing hydrogen from renewable energy according to claim 3, further comprising an alternating current (AC) powered device, wherein the AC powered device is connected to the DC bus via an electrical inverter included in the electrical conversion device, and the control terminal of the controller is connected to the electrical inverter.

6. The system for producing hydrogen from renewable energy according to claim 3, further comprising a hydrogen separation and purification system shared by the primary hydrogen production system and the secondary hydrogen production system.

7. A method for controlling a system for producing hydrogen from renewable energy, wherein the system comprises a renewable-energy-based power generation system, a primary hydrogen production system a secondary hydrogen production system, and a controller, an output end of the renewable-energy-based power generation system is connected to the primary hydrogen production system and the secondary hydrogen production system via an electrical conversion device; a monitoring end of the controller is connected to the output end of the renewable-energy-based power generation system, and a control end of the controller is connected to the electrical conversion device; and a capacity of the primary hydrogen production system is greater than or equal to a capacity of the secondary hydrogen production system, the method comprising: acquiring an operating parameter of the secondary hydrogen production system as a first threshold; acquiring an operating parameter of the primary hydrogen production system as a second threshold; monitoring, by the controller, an output electrical performance parameter of the renewable-energy-based power generation system in real time; controlling the secondary hydrogen production system to be turned on or turned off based on whether the output electrical performance parameter being greater than the first threshold; and controlling the primary hydrogen production system to be turned on or turned off based on whether the output electrical performance parameter being greater than the second threshold, wherein the first threshold value is less than the second threshold value.

8. The method according to claim 7, further comprising: controlling the secondary hydrogen production system to be turned off and maintaining the primary hydrogen production system to be turned on, in a case where the output electrical performance parameter is greater than the second threshold and is less than a sum of the first threshold and the second threshold.

9. The method according to claim 7, further comprising: controlling the secondary hydrogen production system to be turned off and maintaining the primary hydrogen production system to be turned on, or controlling the secondary hydrogen production system and the primary hydrogen production system both to be turned on, in a case where the output electrical performance parameter is greater than a sum of the first threshold and the second threshold, and is less than a rated parameter of the primary hydrogen production system.

10. The method according to claim 7, further comprising: acquiring a sum of a rated parameter of the secondary hydrogen production system and a rated parameter of the primary hydrogen production system, as a third threshold; and controlling the energy storage unit or grid to be turned on and charged based on whether the output electrical performance parameter being greater than the third threshold.

11. The method according to claim 7, further comprising: controlling the energy storage unit or grid to be turned on and charged based on whether the output electrical performance parameter being less than the first threshold.

12. The method according to claim 11, further comprising: controlling the energy storage unit or grid to be turned on and discharge based on whether the output electrical performance parameter being less than an operating parameter for a hot standby condition, wherein the operating parameter for the hot standby condition is less than the first threshold.

13. The method according to claim 7, wherein a power generation capacity of the renewable-energy-based power generation system is in a range of one to two times of the rated parameter of the primary hydrogen production system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0052] FIG. 1 is a diagram showing a power curve corresponding to an equalized configuration scheme in which a power generation capacity of a renewable-energy-based power generation system is configured equivalent to a rated parameter of a primary hydrogen production system;

[0053] FIG. 2 is a schematic diagram of a system for producing hydrogen from renewable energy according to a first embodiment of the present disclosure;

[0054] FIG. 3 is a diagram showing a power curve corresponding to a scheme in which a power generation capacity of a renewable-energy-based power generation system is configured equal to 1.5 times of a rated parameter of electrolytic cells of a primary hydrogen production system:

[0055] FIG. 4 is a schematic diagram of a system for producing hydrogen from renewable energy according to a second embodiment of the present disclosure;

[0056] FIG. 5 is a schematic diagram of a system for producing hydrogen from renewable energy according to a third embodiment of the present disclosure;

[0057] FIG. 6 is a schematic diagram of a system for producing hydrogen from renewable energy according to a fourth embodiment of the present disclosure; and

[0058] FIG. 7 is a schematic flowchart of a method for controlling a system for producing hydrogen from renewable energy according to an embodiment of the present disclosure.

[0059] Reference numerals in the drawings are listed and explained as follows. [0060] 1: Renewable-energy-based power generation system; [0061] 2: DC bus; [0062] 3: Primary hydrogen production system; [0063] 4: Secondary hydrogen production system; [0064] 5: Energy storage unit; [0065] 6: Controller; [0066] 7: AC powered device within the hydrogen production system; [0067] 8: Primary electrical converter; [0068] 9: Secondary electrical converter; [0069] 10: bi-directional electrical converter; [0070] 11: Electrical inverter; [0071] 12: Hydrogen separation and purification system; [0072] 13: DC/AC electrical converter; and [0073] 14: Grid.

DETAILED DESCRIPTION

[0074] Hereinafter, technical solutions of the present application are illustrated in detail through embodiments and in conjunction with drawings.

[0075] In order to better illustrate the present disclosure and facilitate understanding of the technical solutions of the present disclosure, typical but non-limiting embodiments of the present disclosure are described as follows.

[0076] FIG. 7 is a schematic flowchart of a method for controlling a system for producing hydrogen from renewable energy according to an embodiment of the present disclosure. As shown in FIG. 7, the method includes situations T1 to T6 as follows.

[0077] In T1, an output electrical performance parameter is less than or equal to an operating parameter for a hot standby condition. In this situation, by using the controller, the bi-directional electrical converter is controlled to be turned on, and the primary electrical converter and the secondary electrical converter are both controlled to be turned off, so that the energy storage unit or grid is controlled to discharge, aiming to achieve and maintain a condition where the output electrical performance parameter is greater than or equal to the operating parameter for a hot standby condition, and the secondary hydrogen production system and the primary hydrogen production system are controlled to be turned off.

[0078] In T2, the output electrical performance parameter is greater than the operating parameter for a hot standby condition, and is less than or equal to a first threshold. In this situation, by using the controller, the bi-directional electrical converter is controlled to be turned on, and the primary electrical converter and the secondary electrical converter are both controlled to be turned off, so that the energy storage unit or grid is controlled to be charged, and the secondary hydrogen production system and the primary hydrogen production system are controlled to be tuned off.

[0079] In T3, the output electrical performance parameter is greater than the first threshold and is less than or equal to a second threshold. In this situation, by using the controller, the secondary electrical converter is controlled to be turned on, and the primary electrical converter and the bi-directional electrical converter are both controlled to be turned off, so that the secondary hydrogen production system is controlled to be turned on, the primary hydrogen production system is maintained to be turned oft and the energy storage unit or grid is controlled to be tuned off.

[0080] In T4, the output electrical performance parameter is greater than the second threshold and is less than or equal to a sum of the first threshold and the second threshold. In this situation, by using the controller, the primary electrical converter is controlled to be turned on, and the bi-directional electrical converter and the secondary electrical converter are both controlled to be turned off, so that the secondary hydrogen production system is controlled to be turned off the primary hydrogen production system is maintained to be turned on, and the energy storage unit or grid is controlled to be turned off.

[0081] In T5, the output electrical performance parameter is greater than the sum of the first threshold and the second threshold, and is less than or equal to a third threshold. In this situation, by using the controller, the primary electrical converter and the secondary electrical converter are both controlled to be turned on, and the bi-directional electrical converter is controlled to be turned off, so that the secondary hydrogen production system and the primary hydrogen production system are both controlled to be turned on, and the energy storage unit or grid is controlled to be tuned off.

[0082] In T6, the output electrical performance parameter is greater than the third threshold. In this situation, by using the controller, the primary electrical converter, the secondary electrical converter, and the bi-directional electrical converter are all controlled to be turned on, so that the secondary hydrogen production system and the primary hydrogen production system are both controlled to be turned on, and the energy storage unit or grid is controlled to be charged.

First Embodiment

[0083] A system for producing hydrogen from renewable energy and a method for controlling the system are provided according to this embodiment. As shown in FIG. 2, the system for producing hydrogen from renewable energy includes a renewable-energy-based power generation system 1, a DC bus 2, a primary hydrogen production system 3, a secondary hydrogen production system 4, an energy storage unit 5, a controller 6, an AC powered device 7 within the hydrogen production system, and an electrical converter. The electrical converter includes a primary electrical converter 8, a secondary electrical converter 9, a bi-directional electrical converter 10, and an electrical inverter 11. The renewable-energy-based power generation system 1 is a photovoltaic array. The primary hydrogen production system 3 includes one primary electrolytic cell for hydrogen production, the secondary hydrogen production system 4 includes one secondary electrolytic cell for hydrogen production.

[0084] An output end of the renewable-energy-based power generation system 1 is connected to the DC bus 2. The DC bus 2 is connected to a power supply end of the primary hydrogen production system 3 via the primary electrical converter 8. The DC bus 2 is connected to a power supply end of the secondary hydrogen production system 4 via the secondary electrical converter 9. The DC bus 2 is connected to the energy storage unit 5 via the bi-directional electrical converter 10. The DC bus 2 is connected to the AC powered device 7 within the hydrogen production system via the electrical inverter 11.

[0085] A monitor end of the controller 6 is connected to the DC bus 2. A control end of the controller 6 is connected to the primary electrical converter 8, the secondary electrical converter 9, the bi-directional electrical converter 10, and the electrical inverter 11.

[0086] The system for producing hydrogen from renewable energy further includes a hydrogen separation and purification system 12, which is shared by the primary hydrogen production system 3 and the secondary hydrogen production system 4. The hydrogen separation and purification system 12 is placed in open air in a skid-mounted manner, and is configured to outlet or collect produced oxygen in situ, and collect produced hydrogen.

[0087] The method for controlling the system for producing hydrogen from renewable energy includes: acquiring an operating power for a hot standby condition, acquiring an operating power of the secondary hydrogen production system as a first threshold, acquiring an operating power of the primary hydrogen production system as a second threshold, and acquiring a sum of a rated power of the secondary hydrogen production system and a rated power of the primary hydrogen production system, as a third threshold; monitoring, by the controller, an output electrical power of the renewable-energy-based power generation system in real time; controlling the secondary hydrogen production system, the primary hydrogen production system and the energy storage unit or grid to be turned on/off based a relationship among the output electrical power, the operating power for the hot standby condition, the first threshold, the second threshold, the rated power of the primary hydrogen production system, and the third threshold.

[0088] It is set that: the rated power of the primary hydrogen production system is 100%; a power generation capacity of the renewable-energy-based power generation system is 1.5 times (150%) of the rated power of the primary hydrogen production system; and the rated power of the secondary hydrogen production system is 30% of the rated power of the primary hydrogen production system (that is, the capacity of the primary hydrogen production system is greater than the capacity of the secondary hydrogen production system). It is further obtained that, the operating power for the hot standby condition is 1%, the first threshold is 10%, the second threshold is 30%, and the third threshold is 130%. The control method specifically includes the following situations T1 to T6.

[0089] In T1, the output electrical power is less than or equal to the operating power (1%) for the hot standby condition. In this situation, by using the controller, the bi-directional electrical converter is controlled to be turned on, and the primary electrical converter and the secondary electrical converter are both controlled to be turned off, so that the energy storage unit or grid is controlled to discharge, aiming to achieve and maintain a condition where the output electrical power is greater than or equal to the operating power for a hot standby condition, and the secondary hydrogen production system and the primary hydrogen production system are controlled to be turned off.

[0090] In T2, the output electrical power is greater than the operating power (1%) for the hot standby condition, and is less than or equal to the first threshold (10%). In this situation, by using the controller, the bi-directional electrical converter is controlled to be turned on, and the primary electrical converter and the secondary electrical converter are both controlled to be turned off so that the energy storage unit or grid is controlled to be charged, and the secondary hydrogen production system and the primary hydrogen production system are controlled to be turned off.

[0091] In T3, the output electrical power is greater than the first threshold (10%) and is less than or equal to the second threshold (30%). In this situation, by using the controller, the secondary electrical converter is controlled to be turned on, and the primary electrical converter and the bi-directional electrical converter are both controlled to be turned off, so that the secondary hydrogen production system is controlled to be turned on, the primary hydrogen production system is maintained to be turned off and the energy storage unit or grid is controlled to be turned off.

[0092] In T4, the output electrical power is greater than the second threshold (30%) and is less than or equal to a sum (40%) of the first threshold and the second threshold. In this situation, by using the controller, the primary electrical converter is controlled to be turned on, and the bi-directional electrical converter and the secondary electrical converter are both controlled to be turned off, so that the secondary hydrogen production system is controlled to be turned off, the primary hydrogen production system is maintained to be turned on, and the energy storage unit or grid is controlled to be turned off.

[0093] In T5, the output electrical power is greater than the sum (40%) of the first threshold and the second threshold, and is less than or equal to a third threshold (130%). In this situation, by using the controller, the primary electrical converter and the secondary electrical converter are both controlled to be turned on, and the bi-directional electrical converter is controlled to be turned off so that the secondary hydrogen production system and the primary hydrogen production system are both controlled to be turned on, and the energy storage unit or grid is controlled to be tuned off.

[0094] In T6, the output electrical power is greater than the third threshold (130%). In this situation, by using the controller, the primary electrical converter, the secondary electrical converter, and the bi-directional electrical converter are all controlled to be turned on, so that the secondary hydrogen production system and the primary hydrogen production system are both controlled to be tuned on, and the energy storage unit or grid is controlled to be charged.

[0095] Based on the over-configuration scheme, the primary hydrogen production system, and the secondary hydrogen production system, a power curve of the photovoltaic array on one day with best power generation throughout a year is shown in FIG. 3. As shown in FIG. 3, a peak value is 150% (a maximum power corresponding to the DC bus), and a power loss of power generation by the photovoltaic array occurs only when the output electrical power is less than or equal to the first threshold (10%) or when the output electrical power is greater than the third threshold (130%). Based on statistics, among 365 days of the year, the power loss accounts for less than 5% of the total power generation in the year, and the power abandonment ratio is significantly reduced. In addition, power in such power loss is mainly stored by the energy storage unit, which not only allows the capacity of the energy storage unit to be reduced, but also further reduces the power loss, thereby reducing the cost of hydrogen production.

Second Embodiment

[0096] A system for producing hydrogen from renewable energy and a method for controlling the system are provided according to this embodiment. As shown in FIG. 4, the system and the control method are identical to those described in the first embodiment except that; a wind power generator is substituted with the photovoltaic array in the renewable-energy-based power generation system 1, and a AC/DC electrical converter 13 is provided between the wind power generator and the DC bus 2. An AC input end of the AC/DC electrical converter 13 is connected to an output end of the wind power generator, and a DC output end of the AC/DC electrical converter 13 is connected to the DC bus 2.

Third Embodiment

[0097] A system for producing hydrogen from renewable energy and a method for controlling the system are provided according to this embodiment. As shown in FIG. 5, the system is identical to those described in the first embodiment except that: the energy storage unit 5 is substituted with a grid 14 which is configured to power the AC powered device within the hydrogen production system 7, and thus the electrical inverter 11 can be removed. In the method for controlling the system for producing hydrogen from renewable energy, the grid 14 is applied to maintain the condition where the output electrical power is greater than or equal to the operating power for the hot standby condition in a case where the output power meets situation T1; and the power generated in the renewable-energy-based power generation system 1 (photovoltaic array) that cannot be used for hydrogen production is incorporated into the grid 14 for use, in a case where the output electrical power meets situation T2 or T6. According to the present disclosure, there is a small amount of power in the hydrogen production system that cannot be used for hydrogen production. Therefore, the power to be incorporated into the grid 14 can be reduced, thereby reducing effect or dependency on the grid 14.

Fourth Embodiment

[0098] A system for producing hydrogen from renewable energy and a method for controlling the system are provided according to this embodiment. As shown in FIG. 6, the system is identical to those described in the third embodiment except that: the photovoltaic array is substituted with a wind power generator in the renewable-energy-based power generation system 1, and a AC/DC electrical converter 13 is provided between the wind power generator and the DC bus 2. An AC input end of the AC/DC electrical converter 13 is connected to an output end of the wind power generator, and a DC output end of the AC/DC electrical converter 13 is connected to the DC bus 2.

[0099] In summary, the system for producing hydrogen from renewable energy in the present disclosure includes a renewable-energy-based power generation system a primary hydrogen production system, a secondary hydrogen production system, and a controller. An output end of the renewable-energy-based power generation system is connected to the primary hydrogen production system and the secondary hydrogen production system via an electrical conversion device. A capacity of the primary hydrogen production system is greater than or equal to a capacity of the secondary hydrogen production system. The controller is configured to monitor an output electrical performance parameter of the renewable-energy-based power generation system in real time, and control turn on and turn off of the primary hydrogen production system and the secondary hydrogen production system. In this way, a power utilization range of renewable energy is improved, a power generated from renewable energy is used for hydrogen production to a maximum extend, a cost of hydrogen production from renewable energy is reduced, and an engineering practicability is improved.

[0100] It is to be noted that, although detailed structural features of the present disclosure are illustrated through the above embodiments, the present disclosure is not limited to detailed structural features above, that is, the present disclosure is not intended to be implemented necessarily depending on the structural features. It shall be apparent to those skilled in the art that any modification of the present disclosure, an equivalent replacement of a component in the present disclosure, an addition of an auxiliary component, a selection of a specific manner, and the like, shall all fall within the protection scope of and disclosed scope of the specification.

[0101] Preferred embodiments of the present disclosure are described in detail above. However, the present disclosure is not limited to details in the above embodiments, and various simple variants of the technical solutions of the present disclosure may be made within the scope of the technical conception of the present disclosure, and these simple variants shall fall within the protection scope of the present disclosure.

[0102] It should be further noted that the specific technical features described m the embodiments may be combined in any suitable manner without causing contradiction. Various possible combinations are not illustrated in the present disclosure to avoid unnecessary repetition.

[0103] In addition, various embodiments of the present disclosure may be combined arbitrarily without violating the idea of the present disclosure, and the combinations shall be regarded as being disclosed in the present disclosure.