Hydrogen storage and supply system suitable for wide-range pressure fluctuation and control method thereof

Abstract

The invention provides a hydrogen storage and supply system suitable for wide-range pressure fluctuation and a control method thereof, and relates to the technical field of hydrogen storage and supply. In wind-solar power generation coupling hydrogen production and hydrogen utilization projects, in order to make full use of the buffering capacity of a hydrogen storage tank, the designed hydrogen storage tank is generally wide in pressure fluctuation range and low in hydrogen storage pressure lower limit, and therefore the problems that the designed inlet pressure of a downstream compressor unit of the hydrogen storage tank is low, and compression power consumption is large are solved. By designing a plurality of decompression pressure grades and a plurality of hydrogen supply lines which can be switched along with the pressure change of the hydrogen storage tank, the effects of fully utilizing the capacity of the hydrogen storage tank and reducing the compression power consumption of the compressor unit can be simultaneously realized.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen storage and supply, and in particular to a hydrogen storage and supply system adaptable to wide range pressure fluctuations and a control method thereof. Background Art

[0002] Hydrogen energy has received great attention because it can be used for decarbonization in difficult-to-electrify areas such as heavy industry and heavy-load transportation on the load side, can help absorb large-scale renewable energy such as wind and solar power on the power generation side, and can provide power auxiliary services such as peak-shaving and frequency regulation through the mutual conversion of "electricity-hydrogen" on the grid side to improve grid stability. Among them, wind and solar power generation coupled with hydrogen production and large-scale hydrogen utilization projects are currently the main form of development of hydrogen energy demonstration projects on the power generation side, and are expected to be the main way to produce green hydrogen and hydrogen derivatives in the future.

[0003] In large-scale projects of wind-solar power generation coupled with hydrogen production and utilization, hydrogen storage tanks are an indispensable and important component. They are the key link to smooth out the volatility of wind-solar power generation, cope with the intermittent and random nature of wind-solar power generation, and provide downstream with matching hydrogen load regulation capabilities and relatively stable hydrogen supply. Considering the maturity of the technology and the fact that large-scale projects of wind-solar power generation coupled with hydrogen production and utilization are often located in sparsely populated Shagohuang areas, existing large-scale projects of wind-solar power generation coupled with hydrogen production and utilization often adopt the design of gaseous hydrogen storage tanks.

[0004] In order to fully utilize the capacity of the gaseous hydrogen storage tank, the minimum design pressure of the gaseous hydrogen storage tank needs to be as low as possible, and the pressure fluctuation range during system operation should be as large as possible. Since the downstream hydrogen load usually requires a stable hydrogen supply pressure, the centrifugal compressor units commonly used in large-flow hydrogen supply scenarios are limited by their working characteristics and need to maintain a stable inlet pressure. Therefore, the inlet pressure of the centrifugal compressor unit needs to be lower than the minimum pressure of the gaseous hydrogen storage tank, resulting in a high boost ratio and high power consumption of the centrifugal compressor unit. Summary of the invention

[0005] The purpose of the present invention includes providing a hydrogen storage and supply system that can adapt to a wide range of pressure fluctuations and a control method thereof. By designing multiple pressure reduction levels and multiple hydrogen supply lines that can be switched as the pressure of the hydrogen storage tank changes, it is possible to simultaneously achieve the effect of fully utilizing the capacity of the hydrogen storage tank and reducing the compression power consumption of the compressor unit.

[0006] The embodiments of the present invention can be implemented as follows:

[0007] In a first aspect, the present invention provides a hydrogen storage and supply system that can adapt to a wide range of pressure fluctuations, the system comprising a hydrogen storage tank, a hydrogen supply line, a compression subsystem and a return line;

[0008] The plurality of hydrogen storage tanks are connected to the compression subsystem via the hydrogen supply line, and the plurality of compression subsystems are connected in series in sequence to form a multi-stage compression system, wherein the plurality of hydrogen storage tanks are connected to a first-stage compression subsystem via one hydrogen supply line, and the last-stage compression subsystem refluxes hydrogen to the hydrogen storage tank via the reflux line.

[0009] In an optional embodiment, each of the hydrogen supply lines includes a switch valve, a first regulating valve and a first one-way valve arranged in sequence along the gas flow direction; wherein, the first regulating valve is connected to a first pressure monitoring, control and alarm device, and the first pressure monitoring, control and alarm device takes the inlet pressure of the compression subsystem as a control target, so as to maintain the stability of the inlet pressure of the compression subsystem when the pressure of the hydrogen storage tank fluctuates and the outlet hydrogen flow rate fluctuates.

[0010] In an optional embodiment, each of the compression subsystems includes an inlet buffer tank, a centrifugal compressor, an outlet buffer tank, a cooler, an outlet check valve, a reflux regulating valve and a reflux check valve which are arranged in sequence; in each of the compression subsystems, the reflux regulating valve is connected to a second pressure monitoring control alarm device, the reflux regulating valve in the last-stage compression subsystem takes the outlet pressure of the outlet buffer tank as a control target, and the reflux regulating valves in the remaining stages of the compression subsystems take the inlet pressure of the next-stage compression subsystem as a control target, so that when the inlet hydrogen flow rate of each stage of the compression subsystem fluctuates, the inlet pressure of the compression subsystems from the second stage to the last stage and the outlet pressure of the last stage of the compression subsystem are stabilized.

[0011] In an optional embodiment, the centrifugal compressor in each stage of the compression subsystem is operated using a separate shaft, so that the centrifugal compressor in each stage of the compression subsystem can be started and stopped independently.

[0012] In an optional embodiment, the reflux line includes a second one-way valve, a second regulating valve and a third one-way valve arranged in sequence along the gas flow direction; wherein the second regulating valve is connected to the third pressure monitoring control alarm device, and the system outlet pressure is taken as the control target, so as to maintain the system outlet pressure stable when the system outlet flow fluctuates.

[0013] In a second aspect, the present invention provides a control method for a hydrogen storage and supply system that is adaptable to wide range pressure fluctuations. The control method is applied to the system described in the aforementioned embodiment. When the outlet pressure of the hydrogen storage tank is higher than (P N +A)MPa, where P N is the rated inlet pressure of the last stage (Nth stage) compression subsystem, A is a set value considering the pressure loss during the system pressure drop process, and the method includes:

[0014] S1: Control the switch valves on the hydrogen supply line from the hydrogen storage tank to the 1st to (N-1)th compression subsystems to be in a closed state, the switch valves on the hydrogen supply line from the hydrogen storage tank to the Nth compression subsystem to be in an open state, the centrifugal compressors in the 1st to (N-1)th compression subsystems to be in a shutdown hot standby state, and the centrifugal compressor in the Nth compression subsystem to be in an operating state;

[0015] S2: When the outlet pressure of the hydrogen storage tank drops below (P N +A)MPa, open the switch valve on the hydrogen supply line from the hydrogen storage tank to the (N-1)th stage compression subsystem;

[0016] S3: After S2 is completed and the system is stable, the centrifugal compressor in the (N-1)th compression subsystem is started;

[0017] S4: After S3 is completed and the system is stable, close the switch valve on the hydrogen supply line from the hydrogen storage tank to the Nth stage compression subsystem;

[0018] S5: Similarly, when the outlet pressure of the hydrogen storage tank drops below (P2+A)MPa, the switch valve on the hydrogen supply line from the hydrogen storage tank to the first-stage compression subsystem is opened;

[0019] S6: After S5 is completed and the system is stable, the centrifugal compressor in the first stage compression subsystem is started;

[0020] S7: After S6 is completed and the system is stable, close the switch valve on the hydrogen supply line from the hydrogen storage tank to the second-stage compression subsystem.

[0021] In an optional embodiment, when the outlet pressure of the hydrogen storage tank rises to higher than (P2+B) MPa, B is a set value considering the pressure loss during the system pressure rise process, B>A, and the method includes the following steps:

[0022] S8: Open the switch valve on the hydrogen supply line from the hydrogen storage tank to the second-stage compression subsystem;

[0023] S9: After S8 is completed and the system is stable, close the switch valve on the hydrogen supply line from the hydrogen storage tank to the first-stage compression subsystem;

[0024] S10: after S9 is completed and the system is stable, the centrifugal compressor in the first-stage compression subsystem is switched to a shutdown hot standby state;

[0025] S11: Similarly, when the outlet pressure of the hydrogen storage tank rises to a value higher than (P N +B)MPa, open the switch valve on the hydrogen supply line from the hydrogen storage tank to the Nth stage compression subsystem;

[0026] S12: After S11 is completed and the system is stable, close the switch valve on the hydrogen supply line from the hydrogen storage tank to the (N-1)th stage compression subsystem;

[0027] S13: After S12 is completed and the system is stable, the centrifugal compressor in the (N-1)th stage compression subsystem is switched to a shutdown hot standby state.

[0028] The beneficial effects of the hydrogen storage and supply system and control method thereof adapted to wide range pressure fluctuations provided by the embodiments of the present invention include:

[0029] 1. By designing multiple pressure reduction levels and multiple hydrogen supply lines that can be switched as the pressure of the gaseous hydrogen storage tank area changes, it is possible to shut down some compressors when the hydrogen storage tank is at a higher pressure level, thereby minimizing the ratio of pressure reduction and pressure increase while ensuring that the hydrogen storage tank can reach the lowest possible minimum pressure and maximize the use of the storage capacity of the hydrogen storage tank area, thereby minimizing the compression power consumption within a wide range of pressure fluctuations in the gaseous hydrogen storage tank area;

[0030] 2. The hydrogen storage and supply system adapted to a wide range of pressure fluctuations provided by the embodiment of the present invention requires less equipment than existing designs, and thus can significantly increase the economy of the entire system operation with less increase in fixed investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 A schematic diagram of the structure of a hydrogen storage and supply system (including an N-stage compression system) that is adaptable to a wide range of pressure fluctuations provided by the present invention;

[0033] Figure 2 A schematic structural diagram of a hydrogen storage and supply system (including a three-stage compression system) that is adaptable to a wide range of pressure fluctuations provided by the present invention.

[0034] Icons: 1-hydrogen storage tank; 2-manual valve; 3-hydrogen supply line; 31-switch valve; 32-first regulating valve; 33-first non-return valve; 4-compression subsystem; 41-inlet buffer tank; 42-centrifugal compressor; 43-outlet buffer tank; 44-cooler; 45-outlet non-return valve; 46-reflux regulating valve; 47-reflux non-return valve; 5-reflux line; 51-second non-return valve; 52-second regulating valve; 53-third non-return valve; 6-first pressure monitoring control alarm device; 7-second pressure monitoring control alarm device; 8-third pressure monitoring control alarm device. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0038] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, they are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0039] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0040] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0041] Please refer to Figure 1 This embodiment provides a hydrogen storage and supply system (referred to as: system) that can adapt to a wide range of pressure fluctuations. The system includes: a hydrogen storage tank 1, a hydrogen supply line 3, a compression subsystem 4 and a reflux line 5.

[0042] A plurality of hydrogen storage tanks 1 are connected to a compression subsystem 4 via a hydrogen supply line 3. The plurality of compression subsystems 4 are connected in series in sequence to form a multi-stage compression system. Figure 1The compression subsystem 4 on the far left is the first stage, and the compression subsystem 4 on the far right is the last stage. Among them, multiple hydrogen storage tanks 1 are connected to the first-stage compression subsystem 4 through a hydrogen supply line 3, that is, the hydrogen supply line 3 corresponds to the compression subsystem 4 one by one, and the compression subsystem 4 of the last stage refluxes hydrogen to the hydrogen storage tank 1 through the reflux line 5.

[0043] Specifically, a manual valve 2 is further provided between the hydrogen storage tank 1 and the hydrogen supply line 3. Each hydrogen supply line 3 includes a switch valve 31, a first regulating valve 32 and a first non-return valve 33 arranged in sequence along the gas flow direction. The first regulating valve 32 is connected to a first pressure monitoring control alarm device 6, where the first pressure monitoring control alarm device 6 takes the inlet pressure of the compression subsystem 4 as a control target, so as to maintain the inlet pressure of the compression subsystem 4 stable when the pressure of the hydrogen storage tank 1 fluctuates and the outlet hydrogen flow fluctuates.

[0044] Each compression subsystem 4 includes an inlet buffer tank 41, a centrifugal compressor 42, an outlet buffer tank 43, a cooler 44, an outlet check valve 45, a reflux regulating valve 46 and a reflux check valve 47, which are arranged in sequence. In each compression subsystem 4, the reflux regulating valve 46 is connected to the second pressure monitoring control alarm device 7. The reflux regulating valve 46 in the last compression subsystem 4 takes the outlet pressure of the outlet buffer tank 43 as the control target, and the reflux regulating valves 46 in the remaining compression subsystems 4 take the inlet pressure of the next compression subsystem 4 as the control target. Under the condition of the inlet hydrogen flow fluctuation of each compression subsystem 4, the inlet pressure of the second to last compression subsystem 4 and the outlet pressure of the last compression subsystem 4 are stabilized.

[0045] The centrifugal compressor 42 in each stage of the compression subsystem 4 is operated by a separate shaft, so that the centrifugal compressor 42 in each stage of the compression subsystem 4 can be started and stopped independently.

[0046] The return line 5 includes a second one-way valve 51, a second regulating valve 52 and a third one-way valve 53 arranged in sequence along the gas flow direction. The second regulating valve 52 is connected to the third pressure monitoring control alarm device 8, and takes the outlet pressure of the system as the control target, so as to maintain the outlet pressure of the system stable when the outlet flow of the system fluctuates.

[0047] This embodiment also provides a control method for the above system (hereinafter referred to as: method), with the initial state being that the outlet pressure of the hydrogen storage tank 1 is higher than (P N +A)MPa as an example, where N is the total number of stages of the compression subsystem 4, P N is the rated inlet pressure of the last stage (Nth stage) compression subsystem 4, and A is a set value considering the pressure loss during the system pressure drop process, which can be 0.2. The method includes the following steps:

[0048] S1: Control the switch valves 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the 1st to (N-1)th compression subsystems 4 to be in a closed state, the switch valves 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the Nth compression subsystem 4 to be in an open state, the centrifugal compressors 42 in the 1st to (N-1)th compression subsystems 4 to be in a shutdown hot standby state, and the centrifugal compressor 42 in the Nth compression subsystem 4 to be in an operating state.

[0049] S2: When the outlet pressure of hydrogen storage tank 1 drops below (P N +A)MPa, open the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the (N-1)th stage compression subsystem 4.

[0050] S3: After S2 is completed and the system is stable, the centrifugal compressor 42 in the (N-1)th stage compression subsystem 4 is started.

[0051] S4: After S3 is completed and the system is stable, close the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the Nth stage compression subsystem 4.

[0052] S5: Similarly, when the outlet pressure of the hydrogen storage tank 1 drops to less than (P2+A) MPa, the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the first-stage compression subsystem 4 is opened.

[0053] Wherein, P2 is the rated inlet pressure of the second-stage compression subsystem 4. The analogy in S5 means that according to the operations of S2 to S4, the outlet pressure of the hydrogen storage tank 1 is increased from (P N +A)MPa decreases to (P N-1 +A)MPa, (P N-2 +A)MPa,..., (P2+A)MPa.

[0054] S6: After S5 is completed and the system is stable, the centrifugal compressor 42 in the first-stage compression subsystem 4 is started.

[0055] S7: After S6 is completed and the system is stable, close the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the second-stage compression subsystem 4. In this way, the outlet pressure of the hydrogen storage tank 1 is reduced and pulled back to a relatively stable state, which can simultaneously achieve the effect of fully utilizing the capacity of the hydrogen storage tank 1 and reducing the compression power consumption of the compressor unit.

[0056] When the outlet pressure of the hydrogen storage tank 1 rises to higher than (P2+B)MPa, B is the set value considering the pressure loss during the system pressure rise process, B>A, which can be 0.3. i +A)MPa levels fluctuate frequently, P iis the rated inlet pressure of the i-th compression subsystem 4, i=2~N. In this embodiment, setting B>A can prevent the outlet pressure of the hydrogen storage tank 1 from rising to (P i +A)MPa, the hydrogen supply line 3 is switched, the switching frequency of the hydrogen supply line 3 is reduced, and the requirements for the system line switching performance are reduced. The method includes the following steps:

[0057] S8: Open the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the second-stage compression subsystem 4.

[0058] S9: After S8 is completed and the system is stable, close the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the first-stage compression subsystem 4.

[0059] S10: After S9 is completed and the system is stable, the centrifugal compressor 42 in the first-stage compression subsystem 4 is switched to a shutdown hot standby state.

[0060] S11: Similarly, when the outlet pressure of hydrogen storage tank 1 rises to a value higher than (P N +B)MPa, the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the Nth stage compression subsystem 4 is opened. The analogy in S11 means that according to the operations of S8 to S10, the outlet pressure of the hydrogen storage tank 1 is increased from (P2+B)MPa to (P3+B)MPa, ..., (P N-1 +B)MPa, (P N +B)MPa.

[0061] S12: After S11 is completed and the system is stable, close the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the (N-1)th stage compression subsystem 4.

[0062] S13: After S12 is completed and the system is stable, the centrifugal compressor 42 in the (N-1)th compression subsystem 4 is switched to a shutdown hot standby state. In this way, the outlet pressure of the hydrogen storage tank 1 is increased and pulled back to a relatively stable state, which can simultaneously achieve the effect of fully utilizing the capacity of the hydrogen storage tank 1 and reducing the compression power consumption of the compressor unit.

[0063] Example

[0064] Please refer to Figure 2Taking the initial state that the outlet pressure of the hydrogen storage tank 1 is higher than the inlet pressure (P3+0.2) MPa of the third-stage (last-stage) compression subsystem 4 as an example, the method includes the following steps: controlling the switch valves 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the first-stage to the second-stage compression subsystem 4 to be in a closed state, the switch valves 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the third-stage compression subsystem 4 to be in an open state, the centrifugal compressors 42 in the first-stage to the second-stage compression subsystem 4 to be in a shutdown hot standby state, and the centrifugal compressor 42 in the third-stage compression subsystem 4 to be in an operating state. When the outlet pressure of the hydrogen storage tank 1 drops to lower than (P3+0.2)MPa, open the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the second-stage compression subsystem 4. After the previous step is completed and the system is stable, start the centrifugal compressor 42 in the second-stage compression subsystem 4. After the previous step is completed and the system is stable, close the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the third-stage compression subsystem 4. Similarly, when the outlet pressure of the hydrogen storage tank 1 drops to lower than (P2+0.2)MPa, open the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the first-stage compression subsystem 4. After the previous step is completed and the system is stable, start the centrifugal compressor 42 in the first-stage compression subsystem 4. After the previous step is completed and the system is stable, close the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the second-stage compression subsystem 4.

[0065] When the outlet pressure of the hydrogen storage tank 1 rises to higher than (P2+0.3)MPa, the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the second-stage compression subsystem 4 is opened. After the previous step is completed and the system is stable, the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the first-stage compression subsystem 4 is closed. After the previous step is completed and the system is stable, the centrifugal compressor 42 in the first-stage compression subsystem 4 is switched to the shutdown hot standby state; similarly, when the outlet pressure of the hydrogen storage tank 1 rises to higher than (P3+0.3)MPa, the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the third-stage compression subsystem 4 is opened. After the previous step is completed and the system is stable, the switch valve 31 on the hydrogen supply line 3 from the hydrogen storage tank 1 to the second-stage compression subsystem 4 is closed. After the previous step is completed and the system is stable, the centrifugal compressor 42 in the second-stage compression subsystem 4 is switched to the shutdown hot standby state.

[0066] The beneficial effects of the hydrogen storage and supply system and control method thereof adapted to wide range pressure fluctuations provided by the embodiments of the present invention include:

[0067] 1. By designing multiple pressure reduction levels and multiple hydrogen supply lines 3 that can be switched as the pressure in the gaseous hydrogen storage tank area 1 changes, it is possible to shut down some compressors when the hydrogen storage tank 1 is at a higher pressure level, thereby minimizing the ratio of pressure reduction and pressure increase as much as possible while ensuring that the hydrogen storage tank 1 can reach the lowest possible minimum pressure and maximize the use of the storage capacity of the hydrogen storage tank area 1, thereby minimizing the compression power consumption within a wide range of pressure fluctuations in the gaseous hydrogen storage tank area 1;

[0068] 2. The hydrogen storage and supply system adapted to a wide range of pressure fluctuations provided by the embodiment of the present invention requires less equipment than existing designs, and thus can significantly increase the economy of the entire system operation with less increase in fixed investment.

[0069] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A hydrogen storage and supply system that adapts to a wide range of pressure fluctuations, It is characterized in that The system comprises a hydrogen storage tank (1), a hydrogen supply line (3), a compression subsystem (4) and a return line (5); The plurality of hydrogen storage tanks (1) are connected to the compression subsystem (4) via the hydrogen supply line (3), and the plurality of compression subsystems (4) are connected in series in sequence to form a multi-stage compression system, wherein the plurality of hydrogen storage tanks (1) are connected to a first-stage compression subsystem (4) via one hydrogen supply line (3), and the last-stage compression subsystem (4) refluxes hydrogen to the hydrogen storage tank (1) via the reflux line (5).

2. The hydrogen storage and supply system adapted to wide range pressure fluctuations according to claim 1, It is characterized in that Each of the hydrogen supply lines (3) comprises a switch valve (31), a first regulating valve (32) and a first non-return valve (33) which are arranged in sequence along the gas flow direction; wherein the first regulating valve (32) is connected to a first pressure monitoring control alarm device (6), and the first pressure monitoring control alarm device (6) takes the inlet pressure of the compression subsystem (4) as a control target, so as to maintain the inlet pressure of the compression subsystem (4) stable when the pressure of the hydrogen storage tank (1) and the outlet hydrogen flow rate fluctuate.

3. The hydrogen storage and supply system adapted to wide range pressure fluctuations according to claim 2, It is characterized in that Each compression subsystem (4) comprises an inlet buffer tank (41), a centrifugal compressor (42), an outlet buffer tank (43), a cooler (44), an outlet check valve (45), a reflux regulating valve (46) and a reflux check valve (47) which are arranged in sequence; in each compression subsystem (4), the reflux regulating valve (46) is connected to a second pressure monitoring control alarm device (7); the reflux regulating valve (46) in the last compression subsystem (4) takes the outlet pressure of the outlet buffer tank (43) as a control target, and the reflux regulating valve (46) in the remaining compression subsystems (4) takes the inlet pressure of the next compression subsystem (4) as a control target. In the case of fluctuations in the inlet hydrogen flow rate of each compression subsystem (4), the inlet pressures of the compression subsystems (4) from the second to the last stage and the outlet pressure of the last stage are stabilized.

4. The hydrogen storage and supply system adapted to wide range pressure fluctuations according to claim 3, It is characterized in that The centrifugal compressor (42) in each stage of the compression subsystem (4) is operated by a separate shaft, so that the centrifugal compressor (42) in each stage of the compression subsystem (4) can be started and stopped independently.

5. The hydrogen storage and supply system adapted to wide range pressure fluctuations according to claim 3, It is characterized in that The return line (5) comprises a second one-way valve (51), a second regulating valve (52) and a third one-way valve (53) which are arranged in sequence along the gas flow direction; wherein the second regulating valve (52) is connected to a third pressure monitoring control alarm device (8), and the outlet pressure of the system is taken as a control target, so that the outlet pressure of the system is kept stable when the outlet flow of the system fluctuates.

6. A control method for a hydrogen storage and supply system adapting to wide range pressure fluctuations, It is characterized in that The control method is applied to the system according to claim 1, when the outlet pressure of the hydrogen storage tank (1) is higher than (P N +A)MPa, where P N is the rated inlet pressure of the last stage (Nth stage) compression subsystem (4), A is a set value considering the pressure loss during the system pressure drop process, and the method comprises: S1: Control the switch valves (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the 1st to (N-1)th compression subsystems (4) to be in a closed state, the switch valves (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the Nth compression subsystem (4) to be in an open state, the centrifugal compressors (42) in the 1st to (N-1)th compression subsystems (4) to be in a shutdown hot standby state, and the centrifugal compressor (42) in the Nth compression subsystem (4) to be in an operating state; S2: When the outlet pressure of the hydrogen storage tank (1) drops below (P N +A) MPa, open the switch valve (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the (N-1)th stage compression subsystem (4); S3: After S2 is completed and the system is stable, the centrifugal compressor (42) in the (N-1)th compression subsystem (4) is started; S4: After S3 is completed and the system is stable, close the switch valve (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the Nth stage compression subsystem (4); S5: Similarly, when the outlet pressure of the hydrogen storage tank (1) drops below (P 2 +A) MPa, open the switch valve (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the first-stage compression subsystem (4); S6: After S5 is completed and the system is stable, the centrifugal compressor (42) in the first-stage compression subsystem (4) is started; S7: After S6 is completed and the system is stable, close the switch valve (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the second-stage compression subsystem (4).

7. The control method of the hydrogen storage and supply system adapting to wide range pressure fluctuations according to claim 6, It is characterized in that When the outlet pressure of the hydrogen storage tank (1) rises to a value higher than (P 2 +B)MPa, B is a set value considering the pressure loss during the system pressure rise process, B>A, and the method comprises the following steps: S8: Opening the switch valve (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the second-stage compression subsystem (4); S9: After S8 is completed and the system is stable, close the switch valve (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the first-stage compression subsystem (4); S10: after S9 is completed and the system is stable, the centrifugal compressor (42) in the first-stage compression subsystem (4) is switched to a shutdown hot standby state; S11: Similarly, when the outlet pressure of the hydrogen storage tank (1) rises to a value higher than (P N +B) MPa, open the switch valve (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the Nth stage compression subsystem (4); S12: After S11 is completed and the system is stable, close the switch valve (31) on the hydrogen supply line (3) from the hydrogen storage tank (1) to the (N-1)th stage compression subsystem (4); S13: After S12 is completed and the system is stable, the centrifugal compressor (42) in the (N-1)th stage compression subsystem (4) is switched to a shutdown hot standby state.

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