Heterogeneous power supply suitable for hybrid hydrogen production system and control method thereof

Abstract

The invention provides a heterogeneous power supply suitable for a hybrid hydrogen production system and a control method thereof, the heterogeneous power supply comprises a direct current heterogeneous power supply and an alternating current heterogeneous power supply, the direct current heterogeneous power supply comprises an independent active DC / DC power supply topological structure and a master-slave DC / DC power supply topological structure, and the alternating current heterogeneous power supply comprises a hybrid hydrogen production system power supply topological structure. According to the scheme, aiming at each power supply topological structure, a corresponding control method is configured by combining the operation characteristics of the hydrogen production module, so that power distribution and coordinated operation of the hybrid hydrogen production system are realized.

Description

Technical Field

[0001] The present application belongs to the technical field of hydrogen production equipment, and specifically, relates to a heterogeneous power supply suitable for a hybrid hydrogen production system and a control method thereof. Background Art

[0002] Hydrogen energy is clean, carbon-free, flexible, efficient, and has a wide range of application scenarios, so the development of hydrogen production technology has received widespread attention. Currently, hydrogen production is mostly done by water electrolysis, and the current mainstream water electrolysis technologies include alkaline water electrolysis technology and proton exchange membrane water electrolysis technology.

[0003] The system for preparing hydrogen by electrolyzing water includes a power supply, which provides electrical energy for the hydrogen preparation system. At present, the power supply can be a photovoltaic power supply and a mains power supply. However, in the existing scheme, the electrical connection between the power supply and the hydrogen production system does not consider the coupling of electrical characteristics, resulting in the problem of poor stability and economy of the power supply of the existing hydrogen production system. Summary of the invention

[0004] In view of this, the purpose of the present application is to propose a heterogeneous power supply suitable for a hybrid hydrogen production system and a control method thereof, so as to solve the problems of poor stability and economy existing in the power supply mode of the hydrogen production system in the prior art.

[0005] In a first aspect, the technical solution of the present application provides a heterogeneous power supply suitable for a hybrid hydrogen production system, including a DC heterogeneous power supply and an AC heterogeneous power supply, wherein:

[0006] The DC heterogeneous power supply is connected between a DC bus and an equipment control system, and the equipment control system includes at least one hydrogen production module; the DC heterogeneous power supply includes an active DC / DC power supply topology structure and a master-slave DC / DC power supply topology structure;

[0007] The active DC / DC power supply topology structure includes a plurality of DC / DC converters, each of which is used to connect to a hydrogen production module, and the active DC / DC power supply topology structure allocates the operating power of each hydrogen production module according to the operating characteristics of different hydrogen production modules; the hydrogen production modules include alkaline hydrogen production modules and PEM hydrogen production modules; the master-slave DC / DC power supply topology structure includes a combination of a plurality of DC / DC converters and a DC isolation device, the DC / DC converter is used to connect to one type of hydrogen production module, and the DC isolation device is connected to another type of hydrogen production module; in the active DC / DC power supply, the alkaline hydrogen production module and the PEM hydrogen production module independently and actively distribute the operating power; in the master-slave DC / DC power supply topology structure, the PEM hydrogen production module actively controls the operating power, and the operating power of the alkaline hydrogen production module is determined according to the difference between the total power on the input side of the master-slave DC / DC power supply topology structure and the operating power of the PEM hydrogen production module;

[0008] The AC heterogeneous power supply is connected between the AC bus and the equipment control system; the AC heterogeneous power supply includes an isolation transformer, a phase-controlled rectifier bridge, a hybrid hydrogen production module control system and a DC / DC converter; wherein the hybrid hydrogen production module control system includes an alkaline hydrogen production module and a plurality of PEM hydrogen production modules connected in parallel with the alkaline hydrogen production module; the isolation transformer is connected between the AC bus and the phase-controlled rectifier bridge, and the current rectified by the phase-controlled rectifier bridge is input into the alkaline hydrogen production module and the PEM hydrogen production module after passing through an inductor.

[0009] In some embodiments, the active DC / DC power supply topology structure is suitable for a heterogeneous power supply of a hybrid hydrogen production system, wherein the active DC / DC power supply topology structure includes a droop power control module; the hydrogen production module connected to the plurality of DC / DC converters in the active DC / DC power supply topology structure includes a plurality of alkaline hydrogen production modules and a plurality of PEM hydrogen production modules;

[0010] The droop power control module allocates power to each of the alkaline hydrogen production modules and each of the PEM hydrogen production modules according to the set operating characteristic curves of each of the alkaline hydrogen production modules and each of the PEM hydrogen production modules, combined with the input power and voltage level allocation strategy of the DC bus.

[0011] Some schemes describe a heterogeneous power supply suitable for a hybrid hydrogen production system, wherein the master-slave DC / DC power supply topology structure includes a droop power control module; the droop power control module is used to control the PEM hydrogen production modules, and allocates power to each PEM hydrogen production module according to the operating characteristics of each PEM hydrogen production module, combined with the power level of the PEM hydrogen production module and the DC bus voltage.

[0012] Some schemes describe a heterogeneous power supply suitable for a hybrid hydrogen production system, wherein the AC heterogeneous power supply includes a current control module; the current control module extracts the DC component of the output current of the phase-controlled rectifier bridge, subtracts the DC component from the actual current of the output current to obtain a ripple current, and distributes the ripple current to each of the PEM hydrogen production modules as a compensation current value according to a set rule; each of the PEM hydrogen production modules determines the power distribution result of each PEM hydrogen production module according to its power demand and the compensation current value.

[0013] In a second aspect, the technical solution of the present application provides a control method for heterogeneous power sources in a hybrid hydrogen production system, comprising:

[0014] The droop control strategy is used to determine the power allocation results of each hydrogen production module in the active DC / DC power supply topology;

[0015] The droop control strategy is used to determine the power allocation results of the PEM hydrogen production module in the master-slave DC / DC power supply topology;

[0016] The power allocation result of the PEM hydrogen production module in the AC heterogeneous power source is determined by using a given current and a current feedforward control strategy.

[0017] In some embodiments, the control method for heterogeneous power sources in a hybrid hydrogen production system, the droop control strategy includes:

[0018] Collect the actual operating voltage U of the hydrogen production module DC ;

[0019] Collect bus rated voltage U L , the bus is a DC bus;

[0020] Determine the droop coefficient K;

[0021] The power distribution result of the hydrogen production module is determined as follows:

[0022]

[0023] In the above, the hydrogen production module is an alkaline hydrogen production module or a PEM hydrogen production module.

[0024] The control method for heterogeneous power sources in a hybrid hydrogen production system described in some schemes determines the droop coefficient K in the following manner:

[0025]

[0026] Among them, ΔU corresponds to the voltage variation range of the hydrogen production module, and ΔQ corresponds to the power adjustment range of the hydrogen production module.

[0027] Some control methods for heterogeneous power sources in hybrid hydrogen production systems described in the scheme:

[0028] In the hybrid hydrogen production system, the operating characteristics of the alkaline hydrogen production module and the operating characteristics of the PEM hydrogen production module satisfy: the lower power limit of the alkaline hydrogen production module is greater than the lower power limit of the PEM hydrogen production module, the upper power limit of the alkaline hydrogen production module is less than the upper power limit of the PEM hydrogen production module, and the power change rate of the alkaline hydrogen production module is less than the power change rate of the PEM hydrogen production module.

[0029] The control method for heterogeneous power sources in a hybrid hydrogen production system described in some schemes, wherein the power allocation result of the PEM hydrogen production module in the AC heterogeneous power source is determined by using a given current and a current feedforward control strategy, includes:

[0030] Determine the initial input current of the corresponding DC / DC converter according to the power allocation result of the PEM hydrogen production module;

[0031] collecting the difference between the output current of the phase-controlled rectifier and the input current of the alkaline hydrogen production module as the ripple current;

[0032] Decomposing the ripple current into multiple parts according to the number of DC / DC converters to obtain a compensation current of each DC / DC converter;

[0033] The actual current of each DC / DC converter is determined according to the superposition result of the initial input current and the compensation current of each DC / DC converter.

[0034] In some schemes, the control method for heterogeneous power sources in a hybrid hydrogen production system, wherein the ripple current is decomposed into multiple parts according to the number of DC / DC converters to obtain the compensation current of each DC / DC converter, comprises:

[0035] Determine the number of electrolyzers in each PEM hydrogen production module;

[0036] Determine the ratio of the number of electrolyzers in different PEM hydrogen production modules to the total number of electrolyzers;

[0037] The ripple current is distributed into a plurality of parts according to the ratio.

[0038] Compared with the prior art, the above solution provided in the embodiment of the present application has the following advantages:

[0039] The above-mentioned scheme provided in the present application provides a heterogeneous power supply and a control method thereof suitable for a hybrid hydrogen production system, wherein the heterogeneous power supply includes a DC heterogeneous power supply and an AC heterogeneous power supply, the DC heterogeneous power supply includes an independent active DC / DC power supply topology structure and a master-slave DC / DC power supply topology structure, and the AC heterogeneous power supply includes a hybrid hydrogen production system power supply topology structure. Among them, the active DC / DC power supply topology structure includes multiple DC / DC converters, each DC / DC converter is used to connect to a hydrogen production module, and the active DC / DC power supply topology structure allocates the operating power of each hydrogen production module according to the operating characteristics of different hydrogen production modules; the master-slave DC / DC power supply topology structure includes a combination of several DC / DC converters and DC isolation devices, the DC / DC converter is used to connect to one type of hydrogen production module, and the DC isolation device is connected to another type of hydrogen production module; the hydrogen production module includes an alkaline hydrogen production module and a PEM hydrogen production module; in the active DC / DC power supply, the alkaline hydrogen production module and the PEM hydrogen production module independently and actively distribute the operating power; the master-slave DC / DC power supply topology In the structure, the PEM hydrogen production module actively controls the operating power, and the operating power of the alkaline hydrogen production module is determined according to the difference between the total power on the input side of the master-slave DC / DC power supply topology and the operating power of the PEM hydrogen production module; the AC heterogeneous power supply is connected between the AC bus and the equipment control system; the AC heterogeneous power supply includes an isolation transformer, a phase-controlled rectifier bridge, a hybrid hydrogen production module control system and a DC / DC converter; wherein the hybrid hydrogen production module control system includes an alkaline hydrogen production module, and a plurality of PEM hydrogen production modules connected in parallel with the alkaline hydrogen production module; the isolation transformer is connected between the AC bus and the phase-controlled rectifier bridge, and the current rectified by the phase-controlled rectifier bridge is input into the alkaline hydrogen production module and the PEM hydrogen production module after passing through the inductor. Through the above scheme provided in this application, for each power supply topology, a corresponding control method is configured in combination with the operating characteristics of the hydrogen production module, thereby realizing the power distribution and coordinated operation of the hybrid hydrogen production system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above-mentioned features and technical advantages of the present application will become clearer and easier to understand through the following description of its embodiments in conjunction with the accompanying drawings.

[0041] Figure 1 This is a schematic diagram of a structure of a heterogeneous power source applicable to a hybrid hydrogen production system according to an embodiment of the present application;

[0042] Figure 2 This is a schematic diagram of the structure of an active DC / DC heterogeneous power supply topology according to an embodiment of the present application;

[0043] Figure 3 This is a schematic diagram of the structure of a master-slave DC / DC heterogeneous power supply topology according to an embodiment of the present application;

[0044] Figure 4This is an architectural topology diagram of an AC heterogeneous power supply according to an embodiment of the present application;

[0045] Figure 5 This is a schematic diagram of the operating characteristic curves of the alkaline hydrogen production module and the PEM hydrogen production module in the hybrid hydrogen production system according to one embodiment of the present application;

[0046] Figure 6 This is a block diagram of active DC / DC heterogeneous power supply control according to an embodiment of the present application;

[0047] Figure 7 This is a block diagram of a master-slave DC / DC heterogeneous power supply control according to an embodiment of the present application;

[0048] Figure 8 This is a schematic diagram of the access method of the alkaline hydrogen production module of the master-slave DC / DC heterogeneous power supply according to an embodiment of the present application;

[0049] Fig. 9 This is a schematic diagram of power distribution of a master-slave hybrid hydrogen production power supply of a master-slave DC / DC heterogeneous power supply according to an embodiment of the present application;

[0050] Fig.10 This is a schematic diagram of a control method of a DC / DC converter in an AC heterogeneous power supply according to an embodiment of the present application;

[0051] Fig.11 This is a flow chart of a control method for heterogeneous power sources in a hybrid hydrogen production system according to an embodiment of the present application. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings. The same parts are represented by the same figure numerals. It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to the directions in the accompanying drawings. The words "inside" and "outside" used refer to the direction toward or away from the geometric center of a specific component, respectively.

[0053] The present application embodiment provides a heterogeneous power source 100 suitable for a hybrid hydrogen production system, such as Figure 1 As shown, it includes a DC heterogeneous power supply and an AC heterogeneous power supply. The DC heterogeneous power supply is connected between a DC bus and an equipment control system, and the equipment control system includes at least one hydrogen production module. The DC heterogeneous power supply includes an active DC / DC power supply topology structure 101 and a master-slave DC / DC power supply topology structure 102; Figure 2The figure shows an independent active DC / DC power supply topology structure, which is connected between the DC bus and the equipment control system. The active DC / DC power supply topology structure includes: a DC / DC converter, a hybrid hydrogen production system including an alkaline hydrogen production module and a PEM hydrogen production module, and an equipment control system. The active DC / DC power supply topology structure 101 includes multiple DC / DC converters, each of which is used to connect to a hydrogen production module. The hydrogen production modules in the figure include an alkaline hydrogen production module and a PEM hydrogen production module. The active DC / DC power supply topology structure 101 allocates the operating power of each hydrogen production module according to the operating characteristics of the different hydrogen production modules. Figure 3 As shown, the master-slave DC / DC power supply topology structure 102 includes a DC / DC converter and a DC isolation device, and the hybrid hydrogen production module includes an alkaline hydrogen production module and a PEM hydrogen production module; the DC / DC converter is used to connect one type of hydrogen production module, and the DC isolation device is used to connect another type of hydrogen production module. As shown in the figure, the DC / DC converter is connected to the PEM hydrogen production module, and the DC isolation device is connected to the alkaline hydrogen production module; in the active DC / DC power supply topology structure 101, the alkaline hydrogen production module and the PEM hydrogen production module both independently and actively distribute operating power; in the master-slave DC / DC power supply topology structure 102, the PEM hydrogen production module actively controls the operating power, and the operating power of the alkaline hydrogen production module is determined according to the difference between the total power on the input side of the master-slave DC / DC power supply and the operating power of the PEM module. Figure 5 shown.

[0054] according to Figure 4 As shown in the topology diagram, the AC heterogeneous power supply 103 is connected between the AC bus and the equipment control system; the AC heterogeneous power supply 103 includes an isolation transformer, a phase-controlled rectifier bridge, a hybrid hydrogen production module control system and a DC / DC converter, wherein the hybrid hydrogen production module control system includes an alkaline hydrogen production module, and a plurality of PEM hydrogen production modules connected in parallel with the alkaline hydrogen production module; the isolation transformer is connected between the AC bus and the phase-controlled rectifier bridge, and the current rectified by the phase-controlled rectifier bridge is input into the alkaline hydrogen production module and the PEM hydrogen production module after passing through an inductor.

[0055] In the above scheme, the active DC / DC power supply topology structure 101 is connected to the DC bus, which can directly determine the DC power supply voltage level. Assuming that the photovoltaic power supply connected to the DC bus has a voltage level of about 1500V, it can also be customized according to user needs. The input voltage level of the hybrid hydrogen production system is relatively low, and usually requires voltage reduction processing. Therefore, it is necessary to use a DC / DC converter to convert the high-level voltage of the DC bus into a low-level voltage suitable for the needs of the hydrogen production system. The DC / DC converter can be selected according to the actual scenario, such as a parallel Buck converter, a parallel three-level Buck converter, etc., according to the scale of the hybrid hydrogen production system and the power level of each hydrogen production module. In order to reasonably allocate the power of different hydrogen production modules in the hybrid hydrogen production system, the adjustment range, operating characteristics and controllability of each hydrogen production module are comprehensively considered. Based on the operating characteristics of the port of the hybrid hydrogen production system, an adaptive power voltage droop control method is proposed. The current power instruction required by the hydrogen production module can be obtained through voltage power droop control, and the power distribution of the electrolysis module is finally realized through the single current inner loop PI control. The control block diagram is as follows Figure 6 As shown in the figure, P is the operating power of each device, U DC is the actual operating voltage, I ref It is the current control target value generated after improved droop control.

[0056] In droop control, power allocation mainly depends on the difference in droop coefficients. The traditional voltage power control is as follows:

[0057]

[0058] Among them U dcmin is the minimum input DC bus voltage, P u is the rated power of the alkaline hydrogen production module or the PEM hydrogen production module, and k' is the droop coefficient. It can be seen from the formula that at different power levels, the smaller the droop coefficient, the more energy is absorbed, and the larger the droop coefficient, the less energy is absorbed. However, the traditional droop coefficient setting method is not suitable for large-scale hybrid hydrogen production systems, and the selection of k' value cannot show the operating characteristics of the alkaline hydrogen production module and the PEM hydrogen production module.

[0059] The present application scheme combines the adjustment range and response speed of the alkaline hydrogen production module and the PEM hydrogen production module to set the following Figure 5 The operating characteristic curve of the hybrid hydrogen production system, where the horizontal axis represents power and the vertical axis represents voltage. In the hybrid hydrogen production system, the adjustable range of the PEM hydrogen production module is wider than that of the alkaline hydrogen production module. Therefore, the PEM hydrogen production module can respond to operating instructions at a lower power and quickly maintain the DC voltage stability at the DC coupling end. Conversely, it has the same function at high power. The alkaline hydrogen production module has a smaller operating adjustment range and can participate in voltage / power stability control within a small range. Figure 5 , the designed interface characteristic curve can be improved by the following formula:

[0060]

[0061] Where ΔU corresponds to Figure 5 The voltage variation range of the linear relationship part in the relationship curve of the middle section UQ of the medium alkaline hydrogen production module or the PEM hydrogen production module, ΔQ corresponds to the adjustment range of the alkaline hydrogen production module or the PEM hydrogen production module.

[0062] According to the improved droop system, combined with the following formula, the power instructions of the alkaline hydrogen production module and the PEM hydrogen production module can be obtained.

[0063]

[0064] like Figure 7 The control logic of the independent master-slave DC / DC power supply topology 102 is shown, combined with Figure 3 As shown in the figure, the master-slave DC / DC power supply topology includes: alkaline hydrogen production module, DC isolation equipment, PEM hydrogen production module and DC / DC converter. The system is networked based on DC power supply. Figure 7 As shown, the structure is coupled with the photovoltaic power source and the wind power source through the DC coupling end. Among them, the PEM hydrogen production module still uses the droop control method provided before, and the voltage level and droop coefficient setting are similar to the implementation method in the aforementioned active DC / DC power supply topology structure 101. The difference is that the alkaline hydrogen production module is based on its voltage level through Figure 8 The DC isolation device shown in the figure is connected to the device control system, such as a solid-state circuit breaker. Figure 7 As shown in the figure, the DC isolation device has no corresponding power controller, so it needs to communicate with the PEM hydrogen production module to provide its operating status (including start and stop, capacity, etc.). The PEM hydrogen production module actively adjusts the output power of its own controller according to the operating requirements of the alkaline hydrogen production module, while the alkaline hydrogen production module passively absorbs the output of renewable energy within the allowable normal operating range. Fig. 9 Shown is a schematic diagram of power distribution of the alkaline hydrogen production module and the PEM hydrogen production module to achieve power matching with the input side of the heterogeneous power supply.

[0065] against Figure 4The AC heterogeneous power supply shown in the figure mainly includes an isolation transformer, a phase-controlled rectifier, an inductor, a capacitor, an alkaline hydrogen production module, a DC / DC converter and a PEM hydrogen production module in its topology. Among them, the phase-controlled rectifier can be selected according to the power and cost requirements of the hydrogen production module, preferably 6-pulse rectification, 12-pulse rectification, 24-pulse rectification and other current topologies, and the DC / DC converter can select non-isolated Buck circuits, multi-level Buck circuits, Cuk circuits, Spice circuits and other topologies, or phase-shifted full-bridge, LLC and other forms of isolated DC / DC circuits. Multiple PEM hydrogen production modules are connected in parallel at both ends of the alkaline hydrogen production module to better share the ripple current. As shown Fig.10 As shown, Figure 3 The feedforward control scheme of the DC / DC converter in the topology shown above can obtain the ripple current value by extracting the DC component of the output current of the phase-controlled rectifier and subtracting it from the actual output current of the phase-controlled rectifier. The ripple current value is decomposed according to the tolerance of the PEM hydrogen production module to the ripple current, and the decomposed ripple current is superimposed on the compensation current value of a single PEM hydrogen production module, and finally the current set value of the DC / DC converter can be obtained. In specific implementation, the inductor ripple current value is calculated according to the system operating range and inductor parameters; according to the principle of optimal efficiency, the ripple current values ​​borne by the alkaline hydrogen production module and the PEM hydrogen production module are determined; according to the number of PEM hydrogen production modules configured, the fluctuating current value shared by each PEM electrolyzer is determined; according to the dynamic characteristics and stability requirements of the PEM system, the control parameters of the DC / DC unit are designed; when the hydrogen production power instruction fluctuates, the instruction is decomposed into low-frequency and high-frequency quantities, and sent to the alkaline hydrogen production device and the PEM hydrogen production device for adjustment.

[0066] The present application also provides a control method for heterogeneous power sources in a hybrid hydrogen production system, which is used to control heterogeneous power sources in each of the above embodiments, such as Fig.11 As shown, the method includes:

[0067] S10: Using a droop control strategy to determine the power allocation results of each hydrogen production module in the active DC / DC power supply topology. The active DC / DC power supply topology includes multiple DC / DC converters, each DC / DC converter is used to connect to a hydrogen production module, and the active DC / DC power supply topology allocates the operating power of each hydrogen production module according to the operating characteristics of different hydrogen production modules. In the active DC / DC power supply, the alkaline hydrogen production module and the PEM hydrogen production module independently and actively allocate the operating power.

[0068] S20: A droop control strategy is used to determine the power distribution result of the PEM hydrogen production module in the master-slave DC / DC power supply topology. The master-slave DC / DC power supply topology includes a combination of several DC / DC converters and DC isolation devices, the DC / DC converter is used to connect to one type of hydrogen production module, and the DC isolation device is connected to another type of hydrogen production module; the hydrogen production module includes an alkaline hydrogen production module and a PEM hydrogen production module. In the master-slave DC / DC power supply topology, the PEM hydrogen production module actively controls the operating power, and the operating power of the alkaline hydrogen production module is determined according to the difference between the total power on the input side of the master-slave DC / DC power supply topology and the operating power of the PEM hydrogen production module.

[0069] S30: Determine the power allocation result of the PEM hydrogen production module in the AC heterogeneous power supply by using a given current and a current feedforward control strategy. The AC heterogeneous power supply is connected between the AC bus and the equipment control system; the AC heterogeneous power supply includes an isolation transformer, a phase-controlled rectifier bridge, a hybrid hydrogen production module control system and a DC / DC converter; wherein the hybrid hydrogen production module control system includes an alkaline hydrogen production module and a plurality of PEM hydrogen production modules connected in parallel with the alkaline hydrogen production module; the isolation transformer is connected between the AC bus and the phase-controlled rectifier bridge, and the current rectified by the phase-controlled rectifier bridge is input into the alkaline hydrogen production module and the PEM hydrogen production module after passing through the inductor.

[0070] Preferably, the droop control strategy in the above solution includes:

[0071] S11: Collect the actual operating voltage U of the hydrogen production module DC .

[0072] S12: Collect bus rated voltage U L , the bus is a DC bus.

[0073] S13: Determine the droop coefficient K by:

[0074]

[0075] Among them, ΔU corresponds to the voltage variation range of the hydrogen production module, and ΔQ corresponds to the power adjustment range of the hydrogen production module.

[0076] S14: Determine the power allocation result of the hydrogen production module in the following manner:

[0077]

[0078] In the above, the hydrogen production module is an alkaline hydrogen production module or a PEM hydrogen production module.

[0079] Preferably, in the AC heterogeneous power supply, the initial input current of the corresponding DC / DC converter is determined according to the power distribution result of the PEM hydrogen production module; the difference between the output current of the phase-controlled rectifier and the input current of the alkaline hydrogen production module is collected as the ripple current; the ripple current is decomposed into multiple parts according to the number of DC / DC converters to obtain the compensation current of each DC / DC converter; the actual current of each DC / DC converter is determined according to the superposition result of the initial input current and the compensation current of each DC / DC converter. Wherein, the decomposition of the ripple current into multiple parts according to the number of DC / DC converters to obtain the compensation current of each DC / DC converter includes: determining the number of electrolyzers in each PEM hydrogen production module; determining the ratio of the number of electrolyzers in different PEM hydrogen production modules to the total number of electrolyzers; and distributing the ripple current into multiple parts according to the ratio.

[0080] The above-mentioned solution provided in the present application is configured with a corresponding control method for each power supply topology structure in combination with the operating characteristics of the hydrogen production module, thereby realizing power distribution and coordinated operation of the hybrid hydrogen production system.

[0081] A person skilled in the art should understand that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the scope of the present application should be included in the protection scope of the present application.

Claims

1. A heterogeneous power source suitable for a hybrid hydrogen production system, characterized in that: It includes DC heterogeneous power supply and AC heterogeneous power supply, among which: The DC heterogeneous power supply is connected between a DC bus and an equipment control system, and the equipment control system includes at least one hydrogen production module; the DC heterogeneous power supply includes an active DC / DC power supply topology structure and a master-slave DC / DC power supply topology structure; The active DC / DC power supply topology structure includes a plurality of DC / DC converters, each of which is used to connect to a hydrogen production module, and the active DC / DC power supply topology structure allocates the operating power of each hydrogen production module according to the operating characteristics of different hydrogen production modules; the hydrogen production modules include alkaline hydrogen production modules and PEM hydrogen production modules; the master-slave DC / DC power supply topology structure includes a combination of a plurality of DC / DC converters and a DC isolation device, the DC / DC converter is used to connect to one type of hydrogen production module, and the DC isolation device is connected to another type of hydrogen production module; in the active DC / DC power supply, the alkaline hydrogen production module and the PEM hydrogen production module independently and actively distribute the operating power; in the master-slave DC / DC power supply topology structure, the PEM hydrogen production module actively controls the operating power, and the operating power of the alkaline hydrogen production module is determined according to the difference between the total power on the input side of the master-slave DC / DC power supply topology structure and the operating power of the PEM hydrogen production module; The AC heterogeneous power supply is connected between the AC bus and the equipment control system; the AC heterogeneous power supply includes an isolation transformer, a phase-controlled rectifier bridge, a hybrid hydrogen production module control system and a DC / DC converter; wherein the hybrid hydrogen production module control system includes an alkaline hydrogen production module and a plurality of PEM hydrogen production modules connected in parallel with the alkaline hydrogen production module; the isolation transformer is connected between the AC bus and the phase-controlled rectifier bridge, and the current rectified by the phase-controlled rectifier bridge is input into the alkaline hydrogen production module and the PEM hydrogen production module after passing through an inductor.

2. The heterogeneous power source suitable for a hybrid hydrogen production system according to claim 1, characterized in that: The active DC / DC power supply topology structure includes a droop power control module; the hydrogen production module connected to the plurality of DC / DC converters in the active DC / DC power supply topology structure includes a plurality of alkaline hydrogen production modules and a plurality of PEM hydrogen production modules; The droop power control module allocates power to each of the alkaline hydrogen production modules and each of the PEM hydrogen production modules according to the set operating characteristic curves of each of the alkaline hydrogen production modules and each of the PEM hydrogen production modules, combined with the input power and voltage level allocation strategy of the DC bus.

3. The heterogeneous power source suitable for a hybrid hydrogen production system according to claim 1 is characterized in that: The master-slave DC / DC power supply topology structure includes a droop type power control module; the droop type power control module is used to control the PEM hydrogen production module, and distributes power to each PEM hydrogen production module according to the operating characteristics of each PEM hydrogen production module, combined with the power level of the PEM hydrogen production module and the DC bus voltage.

4. The heterogeneous power source suitable for a hybrid hydrogen production system according to claim 1, characterized in that: The AC heterogeneous power supply includes a current control module; the current control module extracts the DC component of the output current of the phase-controlled rectifier bridge, subtracts the DC component from the actual current of the output current to obtain a ripple current, and distributes the ripple current to each of the PEM hydrogen production modules as a compensation current value according to a set rule; Each of the PEM hydrogen production modules determines a power allocation result of each of the PEM hydrogen production modules according to its power demand and compensation current value.

5. A control method for heterogeneous power sources in a hybrid hydrogen production system, characterized in that: include: The droop control strategy is used to determine the power allocation results of each hydrogen production module in the active DC / DC power supply topology; The droop control strategy is used to determine the power allocation results of the PEM hydrogen production module in the master-slave DC / DC power supply topology; The power allocation result of the PEM hydrogen production module in the AC heterogeneous power source is determined by using a given current and a current feedforward control strategy.

6. The control method for heterogeneous power sources in a hybrid hydrogen production system according to claim 5 is characterized in that: The droop control strategy includes: Collect the actual operating voltage U of the hydrogen production module DC ; Collect bus rated voltage U L , the bus is a DC bus; Determine the droop coefficient K; The power distribution result of the hydrogen production module is determined as follows: In the above, the hydrogen production module is an alkaline hydrogen production module or a PEM hydrogen production module.

7. The control method for heterogeneous power sources in a hybrid hydrogen production system according to claim 6 is characterized in that: The droop factor K is determined as follows: Among them, ΔU corresponds to the voltage variation range of the hydrogen production module, and ΔQ corresponds to the power adjustment range of the hydrogen production module.

8. The control method for heterogeneous power sources in a hybrid hydrogen production system according to claim 7 is characterized in that: In the hybrid hydrogen production system, the operating characteristics of the alkaline hydrogen production module and the operating characteristics of the PEM hydrogen production module satisfy: the lower power limit of the alkaline hydrogen production module is greater than the lower power limit of the PEM hydrogen production module, the upper power limit of the alkaline hydrogen production module is less than the upper power limit of the PEM hydrogen production module, and the power change rate of the alkaline hydrogen production module is less than the power change rate of the PEM hydrogen production module.

9. The control method for heterogeneous power sources in a hybrid hydrogen production system according to claim 8, characterized in that: The method of using a given current and a current feedforward control strategy to determine the power allocation result of the PEM hydrogen production module in the AC heterogeneous power supply includes: Determine the initial input current of the corresponding DC / DC converter according to the power allocation result of the PEM hydrogen production module; collecting the difference between the output current of the phase-controlled rectifier and the input current of the alkaline hydrogen production module as the ripple current; Decomposing the ripple current into multiple parts according to the number of DC / DC converters to obtain a compensation current of each DC / DC converter; The actual current of each DC / DC converter is determined according to the superposition result of the initial input current and the compensation current of each DC / DC converter.

10. The control method for heterogeneous power sources in a hybrid hydrogen production system according to claim 9, characterized in that: Decomposing the ripple current into multiple parts according to the number of DC / DC converters to obtain the compensation current of each DC / DC converter includes: Determine the number of electrolyzers in each PEM hydrogen production module; Determine the ratio of the number of electrolyzers in different PEM hydrogen production modules to the total number of electrolyzers; The ripple current is distributed into a plurality of parts according to the ratio.

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