A Temperature Equalization Control Method for an Alkaline Electrolyzer Module with a Stack Parallel Configuration

Abstract

The present invention discloses a temperature equilibrium control method for an alkaline electrolyzer module with a stack parallel configuration. The method includes: when the module does not receive a communication signal from an external communication line, all the power input to the module is used for electrolysis of the stack, and the power distribution and temperature equilibrium among the stacks inside the module are achieved through the internal control of a single alkaline electrolyzer module; after the module receives a communication signal from the external communication line, through centralized control among multiple alkaline electrolyzer modules, each stack inside the module operates at the power corresponding to the maximum hydrogen production efficiency at its temperature, and the remaining power input to the module is distributed to the heating devices corresponding to each stack; when coordinated cooperation among the modules is required, each stack inside the module acts according to the communication signal issued by the upper controller. The present invention can maintain the temperature equilibrium of each stack unit inside the module, and ensure the temperature rise of the stack before the external power generation is large, thereby increasing the potential for absorbing the power of the external system.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production by operation of a hydrogen-electricity coupling system in the field of new energy, and in particular to a temperature balance control method for alkaline solution electrolyzer modules of a battery stack parallel configuration. Background Art

[0002] There are many reasons for connecting multiple stacks in parallel to form an alkaline electrolyzer module for operation. In terms of capacity expansion, the electrolysis capacity of a single stack is limited. For large-scale industrial hydrogen production or hydrogen supply at hydrogen refueling stations, it is difficult to meet the production requirements with only one stack. The parallel connection of multiple stacks can increase the electrolysis reaction site, carry out more water electrolysis reactions simultaneously, and greatly increase the hydrogen production. In terms of system stability, a single stack will cause electrolysis performance fluctuations or even shutdown due to electrode aging, electrolyte changes or failures. When multiple stacks are connected in parallel, if individual stacks have problems, the remaining normal stacks can still work, maintain a certain hydrogen production, ensure the stability and continuity of the electrolysis process, and reduce the impact on downstream links. In terms of flexible regulation, different production or gas use periods have different requirements for hydrogen production. After multiple stacks are connected in parallel into modules, the number of working stacks can be flexibly controlled according to actual needs. When hydrogen demand is low, some stacks can be shut down to save energy and reduce costs, and all stacks can be turned on to produce hydrogen at peak times, accurately and flexibly regulating production to adapt to various situations. From the perspective of maintenance and upgrade, the modular structure of multiple stacks in parallel is clearer than a single large and complex electrolysis device. When a stack fails, it is easier to locate the problem and carry out targeted repairs or replacements. After technological development, when there are better performing stacks, some stacks can be easily upgraded and replaced, improving module performance without the need for large-scale transformation of the electrolysis system.

[0003] In an electrolyzer module composed of multiple stacks in parallel, it is crucial to achieve equal temperatures for each stack. First, this can improve the efficiency of electrolysis, because the same temperature can ensure the consistency of the electrochemical reaction rate, avoid different reaction rates caused by temperature differences, and make the production of hydrogen and oxygen more stable and efficient. Secondly, it helps to extend the service life of the stack. Uneven temperature can cause thermal stress, causing damage to the internal materials of the stack due to inconsistent expansion and contraction, such as poor contact between the electrode and the diaphragm, cracks in the diaphragm, etc., and equal temperature can effectively avoid these problems. Furthermore, it can ensure stable and reliable module performance. Uneven temperature will cause different internal resistance of the stack, causing uneven current distribution, further exacerbating temperature differences, while consistent temperature can ensure uniform current distribution, making the performance of the entire module stable, and the output parameters reliable, which is beneficial to subsequent links. Finally, it can also improve energy utilization efficiency and safety. Uneven temperature can easily cause local overheating, resulting in energy waste and safety hazards, while equal temperature can reduce energy loss and avoid safety accidents, improving the safety and energy utilization efficiency of the entire electrolyzer module. Summary of the invention

[0004] The object of the present invention is to provide a temperature equalization control method for an alkaline electrolyzer module with a stack parallel configuration in view of the deficiencies of the prior art.

[0005] The object of the present invention is achieved by the following technical solutions: A temperature equalization control method for an alkaline electrolyzer module with a stack parallel configuration, specifically including: when the alkaline electrolyzer module does not receive a communication signal from an external communication line, all the power input to the alkaline electrolyzer module is used for stack electrolysis, and the power distribution and temperature equalization among the stacks inside the alkaline electrolyzer module are realized through the internal control of a single alkaline electrolyzer module; among them, the internal control of a single alkaline electrolyzer module is divided into module internal control for a separated alkaline liquid circulation loop and module internal control for a shared alkaline liquid circulation loop according to the difference in the alkaline liquid circulation loop structure of the stack unit.

[0006] After the alkaline electrolyzer module receives a communication signal from an external communication line, when there is a power consumption demand caused by a large external power generation, through centralized control among multiple alkaline electrolyzer modules, the stacks inside each alkaline electrolyzer module operate at the power corresponding to the maximum hydrogen production efficiency at the temperature where they are located, and the remaining power input to the alkaline electrolyzer module is distributed to the heating devices corresponding to each stack; when coordinated cooperation among the alkaline electrolyzer modules is required, the stacks inside each alkaline electrolyzer module act according to the communication signal sent by the upper controller.

[0007] Furthermore, the alkaline electrolyzer module includes N stack units connected in parallel. Each stack unit includes a first capacitor, a second capacitor, an interface power converter, and a stack. Each stack is equipped with a heating device, and the stack is an alkaline electrolyzer; among them, both ends of the first capacitor are respectively connected to the two input terminals of the interface power converter, both ends of the second capacitor are respectively connected to the two output terminals of the interface power converter, and the two output terminals of the interface power converter are respectively connected to the two input terminals of the stack; the input-side interfaces of each stack unit are connected in parallel, and the output-side interfaces of each stack unit are connected in parallel to realize the shunt of the power of the alkaline electrolyzer module; the alkaline electrolyzer module can receive the communication signal from the upper controller to realize centralized control among multiple alkaline electrolyzer modules.

[0008] Further, the internal control of the modular in the separate caustic solution circulation loop includes the control of the internal power and the setting of the power reference value. The power reference value consists of the electrolyzer characteristic power, the temperature equalization power, and the voltage protection redundancy. The corresponding power reference value is obtained by subtracting the corresponding temperature equalization power and voltage protection redundancy from the electrolyzer characteristic power. According to the power reference value, the control of the internal power is realized through the control law of the internal power, so as to realize the power distribution and temperature equalization among the stacks in the caustic solution electrolyzer module. Among them, the electrolyzer characteristic power is the power corresponding to the maximum hydrogen production efficiency of the stack at the operating temperature, which is obtained by looking up the data table stored in the internal storage unit of the control system of the caustic solution electrolyzer module. The data table is used to record the power corresponding to the maximum hydrogen production efficiency of the stack at different temperatures. The temperature equalization power is obtained by multiplying the electrolyzer characteristic power by the temperature correction factor corresponding to the stack. The voltage protection redundancy is realized through the control law of the voltage protection redundancy.

[0009] The internal control of the modular in the shared caustic solution circulation loop includes the control of the internal power and the setting of the power reference value. The power reference value consists of the electrolyzer characteristic power and the voltage protection redundancy. The corresponding power reference value is obtained by subtracting the corresponding voltage protection redundancy from the electrolyzer characteristic power. According to the power reference value, the control of the internal power is realized through the control law of the internal power, so as to realize the power distribution among the stacks in the caustic solution electrolyzer module.

[0010] Further, the control law of the internal power is as follows:

[0011] ;

[0012] In the formula, represents the pulse duty cycle of the power semiconductor module of the i-th stack unit in the caustic solution electrolyzer module; and represent the proportional coefficient and integral coefficient of the PI controller respectively, and s is the Laplace operator; represents the power reference value of the stack in the i-th stack unit in the caustic solution electrolyzer module, , represents the electrolyzer characteristic power of the stack in the i-th stack unit in the caustic solution electrolyzer module, represents the temperature equalization power of the stack in the i-th stack unit in the caustic solution electrolyzer module, represents the voltage protection redundancy of the stack in the i-th stack unit in the caustic solution electrolyzer module; represents the power of the stack in the i-th stack unit in the caustic solution electrolyzer module.

[0013] Further, the calculation formula of the temperature equalization power is:

[0014] ;

[0015] Wherein, represents the temperature equalization power of the stack in the i-th stack unit of the alkaline electrolyzer module; represents the electrolyzer characteristic power of the stack in the i-th stack unit of the alkaline electrolyzer module; represents the temperature correction factor of the stack in the i-th stack unit of the alkaline electrolyzer module, and its calculation formula is:

[0016] ;

[0017] Wherein, represents the temperature of the stack in the i-th stack unit of the alkaline electrolyzer module, and N is the total number of stack units in the alkaline electrolyzer module.

[0018] Furthermore, the control law of the voltage protection redundancy is:

[0019] ;

[0020] Wherein, represents the voltage protection redundancy of the stack in the i-th stack unit of the alkaline electrolyzer module; and respectively represent the proportional coefficient and the integral coefficient of the PI controller, and s is the Laplace operator; represents the rated voltage of the stack; represents the terminal voltage of the stack in the i-th stack unit of the alkaline electrolyzer module.

[0021] Further, the centralized control among the multiple alkaline electrolyzer modules specifically includes: the upper controller issues scheduling instructions to each alkaline electrolyzer module through an external communication line. After receiving the communication signal of the external communication line, the alkaline electrolyzer module distributes a part of all the power input to the alkaline electrolyzer module to each stack inside the alkaline electrolyzer module for hydrogen production by electrolysis, and distributes another part of the power to each heating device inside the alkaline electrolyzer module to achieve heating and temperature rise of the corresponding stack; among them, the same method as the internal control of the module of the separated alkaline liquid circulation loop is adopted, that is, the corresponding power reference value is obtained by subtracting the corresponding temperature equalization power and voltage protection redundancy from the characteristic power of the electrolyzer, and the internal power is controlled according to the power reference value through the control law of the internal power to realize the power distribution on each stack inside the alkaline electrolyzer module, so that each stack inside the alkaline electrolyzer module operates at the power corresponding to the maximum hydrogen production efficiency at the current temperature; the total electrolysis power is calculated according to the power distributed to each stack inside the alkaline electrolyzer module, the total heating power is calculated according to all the power input to the alkaline electrolyzer module and the total electrolysis power, and the power distributed to the heating device is obtained by multiplying the total heating power by the corresponding heating equalization factor of the heating device, so as to distribute it to each heating device inside the alkaline electrolyzer module to achieve heating and temperature rise of the corresponding stack.

[0022] Further, the power distributed to the heating device is obtained by multiplying the total heating power by the corresponding heating equalization factor of the heating device, and is calculated by the following formula:

[0023] ;

[0024] ;

[0025] ;

[0026] In the formula, represents the power distributed to the heating device in the i-th stack unit of the alkaline electrolyzer module; represents the heating equalization factor of the heating device in the i-th stack unit of the alkaline electrolyzer module, represents the power of the stack in the i-th stack unit of the alkaline electrolyzer module, and N is the total number of stack units in the alkaline electrolyzer module; represents the total heating power, represents the total power input to the alkaline electrolyzer module, represents the total electrolysis power.

[0027] Further, the alkaline electrolyzer module includes two sets of communication lines, namely the internal communication line between the stacks inside the alkaline electrolyzer module and the external communication line between the alkaline electrolyzer modules.

[0028] Furthermore, the information transmitted by the internal communication lines between the stacks inside the alkaline electrolyzer cell module is the temperature of each stack.

[0029] The information transmitted by the external communication lines between the alkaline electrolyzer cell modules is the total power input to the alkaline electrolyzer cell module.

[0030] The beneficial effects of the present invention are as follows: Through a new control method among the stack units inside the alkaline electrolyzer cell module, the present invention overcomes the problems of slow power response speed of the alkaline electrolyzer cell module and the inability of each stack unit to be fully utilized at the present stage; The present invention adopts the method of parallel current sharing of stack units, increasing the power capacity of the alkaline electrolyzer cell module and solving the problem of too small power of a single stack; The temperature equalization link inside the alkaline electrolyzer cell module realizes the temperature equalization of each stack unit inside the module under the separated alkaline liquid circulation structure; Moreover, the temperature rise of the stack is ensured in advance under the condition of large external power generation, increasing the potential for absorbing the power of the external system; Through the modular integration method, the present invention is conducive to fault detection and plug-and-play; At the same time, the centralized control of each stack inside a single alkaline electrolyzer cell module is the basis for the collaborative hierarchical control among the alkaline electrolyzer cell modules, reducing the calculation amount of the upper control system and further solving the problem of the scale expansion of the hydrogen production base. Description of the Drawings

[0031] Figure 1 is the system structure diagram of the alkaline electrolyzer cell module with a stack parallel configuration of the present invention;

[0032] Figure 2 is the control principle block diagram of a single stack unit in the alkaline electrolyzer cell module of the present invention. Detailed Embodiments

[0033] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. On the contrary, they are merely examples of the devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0034] The terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms of "a", "the", and "said" used in the present invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0035] It should be understood that although the terms first, second, third, etc. may be used in the present invention to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of the present invention, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to a determination".

[0036] The present invention will be described in detail below with reference to the accompanying drawings. In the case of no conflict, the features in the following embodiments and implementation manners can be combined with each other.

[0037] The temperature equalization control method of the stack parallel configuration alkaline electrolyzer module of the present invention can control the temperature equalization between n stack units inside the alkaline electrolyzer module. At the same time, it can quickly raise the temperature before the external power generation is large, that is, before the power output of the external power source increases rapidly.

[0038] The temperature equalization control method of the stack parallel configuration alkaline electrolyzer module of the present invention specifically includes: when the alkaline electrolyzer module does not receive the communication signal of the external communication line, the alkaline electrolyzer module executes the self-operation mode, and all the power input to the alkaline electrolyzer module is used for stack electrolysis and not allocated to the heating device. The power distribution and temperature equalization between the stacks inside the alkaline electrolyzer module are realized through the internal control of a single alkaline electrolyzer module. After the alkaline electrolyzer module receives the communication signal of the external communication line, when there is a power consumption demand caused by large external power generation, the alkaline electrolyzer module switches from the self-operation mode to the heating mode. Through the centralized control between multiple alkaline electrolyzer modules, each stack inside the alkaline electrolyzer module operates at the power corresponding to the maximum hydrogen production efficiency at the temperature where it is located. The remaining power input to the alkaline electrolyzer module is allocated to the heating devices corresponding to each stack. By reasonably allocating the electrolysis power applied to the stack and the heating power applied to the heating device, the temperature of each stack inside the alkaline electrolyzer module can be quickly increased before the external supply power rises significantly, and the power consumption potential can be improved; when coordinated cooperation between each alkaline electrolyzer module is required, each stack inside the alkaline electrolyzer module acts according to the communication signal sent by the upper controller. Among them, the internal control of a single alkaline electrolyzer module is divided into two cases according to the difference in the alkaline liquid circulation loop structure of the stack unit: the module internal control of the separated alkaline liquid circulation loop and the module internal control of the shared alkaline liquid circulation loop.

[0039] In this embodiment, an alkaline electrolyzer module includes N stack units connected in parallel. Each stack unit includes a first capacitor, a second capacitor, an interface power converter, and a stack. Each stack is equipped with a heating device, and the stack is an alkaline electrolyzer. Among them, both ends of the first capacitor are respectively connected to two input terminals of the interface power converter, both ends of the second capacitor are respectively connected to two output terminals of the interface power converter, and two output terminals of the interface power converter are respectively connected to two input terminals of the stack, as Figure 1 shown; the input-side interfaces of each stack unit are connected in parallel, and the output-side interfaces of each stack unit are connected in parallel to achieve power shunting of the alkaline electrolyzer module. The alkaline electrolyzer module can receive communication signals from the upper controller to achieve centralized control among multiple alkaline electrolyzer modules.

[0040] In this embodiment, the internal control of the separated alkaline solution circulation loop module includes the control of internal power and the setting of power reference values. The power reference value is composed of the electrolyzer characteristic power, the temperature equalization power, and the voltage protection redundancy. The corresponding power reference value is obtained by subtracting the corresponding temperature equalization power and voltage protection redundancy from the electrolyzer characteristic power. According to the power reference value, the control of internal power is realized through the control law of internal power to achieve power distribution and temperature equalization among the stacks inside the alkaline electrolyzer module, as Figure 2 shown. Among them, the electrolyzer characteristic power is the power corresponding to the maximum hydrogen production efficiency of the stack at the operating temperature, which is obtained by looking up the data table stored in the internal storage unit of the alkaline electrolyzer module control system. The data table is used to record the power corresponding to the maximum hydrogen production efficiency of the stack at different temperatures; the temperature equalization power is obtained by multiplying the electrolyzer characteristic power by the temperature correction factor corresponding to the stack; the voltage protection redundancy is realized through the control law of the voltage protection redundancy.

[0041] It should be understood that the stack voltage can appropriately exceed the rated stack voltage, and it is required that the stack voltage is less than or equal to 10% of the rated stack voltage. Therefore, in order to prevent the stack voltage from exceeding the limit, voltage protection is set for the stack to limit the electrolysis current, because once the stack current is too large, it will cause the stack voltage to exceed the limit, which is specifically realized through the set voltage protection redundancy.

[0042] It should be noted that recording the power corresponding to the maximum hydrogen production efficiency of the stack at different temperatures, making it into a data table in the form of a lookup table, and then storing the data table in the internal storage unit of the system can directly look up the data table to obtain the power corresponding to the maximum hydrogen production efficiency of the stack at the operating temperature when used later.

[0043] Furthermore, the control law of internal power is:

[0044]

[0045] In the formula, represents the pulse duty cycle of the power semiconductor module of the i-th stack unit in the alkaline electrolyzer module, where the power semiconductor module is an insulated gate bipolar transistor (IGBT); and respectively represent the proportional coefficient and the integral coefficient of the PI controller, and s is the Laplace operator; represents the power reference value of the stack in the i-th stack unit of the alkaline electrolyzer module, , represents the electrolyzer characteristic power of the stack in the i-th stack unit of the alkaline electrolyzer module, represents the temperature equalization power of the stack in the i-th stack unit of the alkaline electrolyzer module, represents the voltage protection redundancy of the stack in the i-th stack unit of the alkaline electrolyzer module; represents the power of the stack in the i-th stack unit of the alkaline electrolyzer module.

[0046] It should be understood that the basic logic of subtracting the corresponding temperature equalization power from the electrolyzer characteristic power is as follows: providing a lower power to the stack with a higher temperature, and the lower power can make the stack heat up slower; providing a higher power to the stack with a lower temperature, and the higher power can make the stack heat up faster. In this way, the temperatures of the stacks inside the alkaline electrolyzer module can converge and tend to be consistent, realizing the power distribution and temperature equalization among the stacks inside the alkaline electrolyzer module.

[0047] Furthermore, the calculation formula for the temperature equalization power is:

[0048]

[0049] In the formula, represents the temperature equalization power of the stack in the i-th stack unit of the alkaline electrolyzer module; represents the electrolyzer characteristic power of the stack in the i-th stack unit of the alkaline electrolyzer module; represents the temperature correction factor of the stack in the i-th stack unit of the alkaline electrolyzer module, and its calculation formula is:

[0050]

[0051] In the formula, represents the temperature of the stack in the i-th stack unit of the alkaline electrolyzer module, and N is the total number of stack units in the alkaline electrolyzer module.

[0052] Furthermore, when the stack is operating normally, it is normal to slightly exceed the rated voltage, and the maximum allowable terminal voltage of the stack is , the voltage protection has a clipping unit, with the lower limit of the clipped value being 0 and the upper limit being the characteristic power of the electrolyzer cell . The control law of the voltage protection redundancy is as follows:

[0053]

[0054] In the formula, represents the voltage protection redundancy of the stack in the i-th stack unit in the alkaline electrolyzer cell module; and respectively represent the proportional coefficient and the integral coefficient of the PI controller, and s is the Laplace operator; represents the rated voltage of the stack; represents the terminal voltage of the stack in the i-th stack unit in the alkaline electrolyzer cell module.

[0055] In this embodiment, for the alkaline electrolyzer cell module with a shared alkaline liquid circulation loop, the internal temperature is equal in real time. Therefore, there is no need to design a dedicated algorithm to achieve temperature balance, and only the corresponding power needs to be allocated to the internal stacks. The internal control of the module with a shared alkaline liquid circulation loop also includes the control of the internal power and the setting of the power reference value. The power reference value is composed of the characteristic power of the electrolyzer cell and the voltage protection redundancy. The corresponding power reference value is obtained by subtracting the corresponding voltage protection redundancy from the characteristic power of the electrolyzer cell. According to the power reference value, the control of the internal power is realized through the control law of the internal power to achieve the power distribution among the internal stacks of the alkaline electrolyzer cell module. Among them, the specific acquisition methods of the characteristic power of the electrolyzer cell and the voltage protection redundancy are the same as those in the internal control of the module with a separated alkaline liquid circulation loop.

[0056] In this embodiment, the centralized control among multiple alkaline electrolyzer modules specifically includes: the upper controller issues scheduling instructions to each alkaline electrolyzer module through an external communication line. After receiving the communication signal of the external communication line, the alkaline electrolyzer module distributes a part of all the power input to the alkaline electrolyzer module to each stack inside the alkaline electrolyzer module for electrolytic hydrogen production, and distributes another part of the power to each heating device inside the alkaline electrolyzer module to achieve the heating and temperature increase of the corresponding stack. Among them, the same method as the internal control of the module with a separated alkaline liquid circulation loop is adopted, that is, the corresponding power reference value is obtained by subtracting the corresponding temperature equalization power and voltage protection redundancy from the characteristic power of the electrolyzer, and the internal power is controlled according to the power reference value through the control law of the internal power to achieve the power distribution on each stack inside the alkaline electrolyzer module, so that each stack inside the alkaline electrolyzer module operates at the power corresponding to the maximum hydrogen production efficiency at its temperature. Furthermore, the total electrolysis power is calculated based on the power distributed to each stack inside the alkaline electrolyzer module, the total heating power is calculated based on all the power input to the alkaline electrolyzer module and the total electrolysis power, and the power allocated to the heating device is obtained by multiplying the total heating power by the corresponding heating equalization factor of the heating device, so as to distribute it to each heating device inside the alkaline electrolyzer module to achieve the heating and temperature increase of the corresponding stack.

[0057] Specifically, the upper controller issues scheduling instructions to each alkaline electrolyzer module through an external communication line. After receiving the communication signal of the external communication line, at this time, the communication signal of the external communication line is the prediction instruction signal for large power generation. The alkaline electrolyzer module switches from the original self-operation mode to the heating mode, starts to reduce the power supplied to the stack, supplies a part of the power to the heating device, and the communication monitoring of the external system among the modules also monitors the predicted value of the external supply power. Before the external large power generation, the electrolysis power is reduced, and more power is distributed to the stack heating device for stack temperature rise. A data table of the power required for the stack to maintain the maximum hydrogen production efficiency at different temperatures is prepared in advance. The corresponding voltage protection redundancy is subtracted from the characteristic power of the electrolyzer as the corresponding power reference value, and it is used as the power reference value of the stack in different stack units and applied to the corresponding stack for electrolysis, and the remaining power is all used in the heating device to achieve the heating and temperature increase of the stack. Since the smaller the electrolysis power, the lower the temperature of the stack unit, and the more power needs to be distributed to promote the heating and temperature increase of the stack.

[0058] Furthermore, the power allocated to the heating device is obtained by multiplying the total heating power by the corresponding heating equalization factor of the heating device, and is calculated through the following formula:

[0059]

[0060]

[0061]

[0062] In the formula, represents the power allocated to the heating device in the i-th stack unit in the alkaline electrolyzer module; represents the heating balance factor of the heating device in the i-th stack unit in the alkaline electrolyzer module, represents the power of the stack in the i-th stack unit in the alkaline electrolyzer module, and N is the total number of stack units in the alkaline electrolyzer module; represents the total heating power, represents the total power input to the alkaline electrolyzer module, represents the total electrolysis power.

[0063] Furthermore, the alkaline electrolyzer module includes two sets of communication lines, namely the internal communication line between stacks inside the alkaline electrolyzer module and the external communication line between alkaline electrolyzer modules.

[0064] Furthermore, the information transmitted by the internal communication line between stacks inside the alkaline electrolyzer module is the temperature of each stack; the information transmitted by the external communication line between alkaline electrolyzer modules is the total power input to the alkaline electrolyzer module.

[0065] In summary, the present invention overcomes the problems of slow power response speed of the alkaline electrolyzer module and the inability of each stack unit to be fully utilized at the present stage through a new control method between stack units inside the alkaline electrolyzer module; the present invention adopts the method of parallel current sharing of stack units to increase the power capacity of the alkaline electrolyzer module and solves the problem of too small power of a single stack; the temperature balance link inside the alkaline electrolyzer module realizes the temperature balance of each stack unit inside the module still under the separated alkaline liquid circulation structure; and it ensures the temperature rise of the stack in advance under the condition of large external power generation, increasing the consumption potential of the external system power; the present invention is beneficial to fault detection and plug-and-play through a modular integration method; at the same time, the centralized control of each stack inside a single alkaline electrolyzer module is the basis for the collaborative hierarchical control between alkaline electrolyzer modules, reducing the calculation amount of the upper control system and further solving the problem of the scale expansion of the hydrogen production base.

[0066] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A temperature balance control method for alkaline solution electrolyzer modules in parallel configuration of a stack, characterized in that: Specifically include: When the alkali liquid electrolyzer module does not receive a communication signal from an external communication line, all power input to the alkali liquid electrolyzer module is used for stack electrolysis, and power distribution and temperature balance among the stacks inside the alkali liquid electrolyzer module are achieved through internal control of a single alkali liquid electrolyzer module; wherein the internal control of a single alkali liquid electrolyzer module is divided into module internal control of a separate alkali liquid circulation loop and module internal control of a shared alkali liquid circulation loop according to the difference in the alkali liquid circulation loop structure of the stack unit; After receiving the communication signal from the external communication line, when there is a demand for power consumption due to a large amount of external power, the alkali liquid electrolyzer module uses centralized control among multiple alkali liquid electrolyzer modules to make each stack inside the alkali liquid electrolyzer module operate at the power corresponding to the maximum hydrogen production efficiency at the temperature, and the remaining power input to the alkali liquid electrolyzer module is distributed to the heating device corresponding to each stack; when coordination and cooperation between the alkali liquid electrolyzer modules is required, each stack inside the alkali liquid electrolyzer module acts according to the communication signal sent by the upper controller; Wherein, the module internal control of the separated alkali liquid circulation loop includes the control of internal power and the setting of power reference value, the power reference value is composed of the characteristic power of the electrolyzer, the temperature balance power and the voltage protection redundancy, and the corresponding power reference value is obtained by subtracting the corresponding temperature balance power and voltage protection redundancy from the characteristic power of the electrolyzer, and the internal power is controlled by the control law of the internal power according to the power reference value, so as to realize the power distribution and temperature balance among the various stacks inside the alkali liquid electrolyzer module; wherein, the characteristic power of the electrolyzer is the power corresponding to the maximum hydrogen production efficiency of the stack at the operating temperature, which is obtained by searching the data table stored in the internal storage unit of the control system of the alkali liquid electrolyzer module, wherein the data table is used to record the power corresponding to the maximum hydrogen production efficiency of the stack at different temperatures; the temperature balance power is obtained by multiplying the characteristic power of the electrolyzer by the temperature correction factor corresponding to the stack; the voltage protection redundancy is realized by the control law of the voltage protection redundancy; The module internal control of the shared alkali solution circulation loop includes the control of the internal power and the setting of the power reference value. The power reference value is composed of the characteristic power of the electrolytic cell and the voltage protection redundancy. The corresponding power reference value is obtained by subtracting the corresponding voltage protection redundancy from the characteristic power of the electrolytic cell. The internal power is controlled according to the power reference value through the control law of the internal power to realize the power distribution between the various stacks inside the alkali solution electrolytic cell module. The centralized control among the plurality of alkali liquid electrolyzer modules specifically includes: the upper-level controller sends a dispatch instruction to each alkali liquid electrolyzer module through an external communication line; after receiving the communication signal of the external communication line, the alkali liquid electrolyzer module distributes a part of all the power input to the alkali liquid electrolyzer module to each battery stack inside the alkali liquid electrolyzer module for electrolysis and hydrogen production, and distributes the other part of the power to each heating device inside the alkali liquid electrolyzer module to realize heating and temperature rise of the corresponding battery stack; wherein, the same method as the internal control of the module of the separated alkali liquid circulation loop is adopted, that is, the corresponding temperature balancing power and voltage protection redundancy are obtained by subtracting the corresponding temperature balancing power and voltage protection redundancy from the characteristic power of the electrolyzer. The power reference value is used to control the internal power through the control law of the internal power according to the power reference value, so as to realize the power distribution on each fuel cell inside the alkali liquid electrolyzer module, so that each fuel cell inside the alkali liquid electrolyzer module operates at the power corresponding to the maximum hydrogen production efficiency at the temperature; the total electrolysis power is calculated according to the power distributed to each fuel cell inside the alkali liquid electrolyzer module, the total heating power is calculated according to all the power input into the alkali liquid electrolyzer module and the total electrolysis power, the total heating power is multiplied by the heating balance factor corresponding to the heating device to obtain the power distributed on the heating device, so as to distribute it to each heating device inside the alkali liquid electrolyzer module to realize the heating and temperature rise of the corresponding fuel cell.

2. The temperature balance control method of the parallel configuration alkaline solution electrolyzer module of the battery stack according to claim 1 is characterized in that: The alkaline liquid electrolyzer module includes N parallel-connected battery stack units, each of which includes a first capacitor, a second capacitor, an interface power converter and a battery stack. Each battery stack is equipped with a heating device, and the battery stack is an alkaline liquid electrolyzer; wherein, the two ends of the first capacitor are respectively connected to the two input ends of the interface power converter, the two ends of the second capacitor are respectively connected to the two output ends of the interface power converter, and the two output ends of the interface power converter are respectively connected to the two input ends of the battery stack; the input side interfaces of each battery stack unit are connected in parallel, and the output side interfaces of each battery stack unit are connected in parallel to realize the diversion of the power of the alkaline liquid electrolyzer module; the alkaline liquid electrolyzer module can receive communication signals from an upper-level controller to realize centralized control among multiple alkaline liquid electrolyzer modules.

3. The temperature balance control method of the parallel configuration alkaline solution electrolyzer module of the battery stack according to claim 1 is characterized in that: The control law of the internal power is: Where, d i k represents the pulse duty cycle of the power semiconductor module of the i-th stack unit in the alkali solution electrolyzer module; p and k j They represent the proportional coefficient and integral coefficient of the PI controller respectively, and s is the Laplace operator; represents the power reference value of the stack in the ith stack unit in the alkaline solution electrolyzer module, P elrefi represents the characteristic power of the cell in the ith cell unit in the alkaline solution electrolyzer module, ΔP elrefi represents the temperature balance power of the stack in the ith stack unit in the alkaline solution electrolyzer module, ΔP vpi represents the voltage protection redundancy of the stack in the ith stack unit in the alkali solution electrolyzer module; P eli Represents the power of the battery stack in the i-th battery stack unit in the alkaline solution electrolyzer module.

4. The temperature balance control method of the parallel configuration alkaline solution electrolyzer module of the battery stack according to claim 1 is characterized in that: The calculation formula of the temperature balancing power is: ΔP elrefi =s i P elrefi In the formula, ΔP elrefi represents the temperature balance power of the stack in the ith stack unit in the alkaline solution electrolyzer module; P elrefi represents the characteristic power of the electrolyzer in the ith cell unit in the alkaline solution electrolyzer module; σ i It represents the temperature correction factor of the stack in the ith stack unit in the alkaline solution electrolyzer module, and its calculation formula is: Where, T eli It represents the temperature of the battery stack in the i-th battery stack unit in the alkaline solution electrolyzer module, and N is the total number of battery stack units in the alkaline solution electrolyzer module.

5. The temperature balance control method of the parallel configuration alkaline solution electrolyzer module of the battery stack according to claim 1 is characterized in that: The control law of the voltage protection redundancy is: In the formula, ΔP vpi represents the voltage protection redundancy of the stack in the ith stack unit in the alkali solution electrolyzer module; k pv and k jv They represent the proportional coefficient and integral coefficient of the PI controller respectively, s is the Laplace operator; u E Indicates the rated voltage of the battery stack; u eli It represents the terminal voltage of the stack in the i-th stack unit in the alkaline solution electrolyzer module.

6. The temperature balance control method of the parallel configuration alkaline solution electrolyzer module of the battery stack according to claim 1 is characterized in that: The power allocated to the heating device is obtained by multiplying the total heating power by the heating balance factor corresponding to the heating device, which is calculated by the following formula: ΔP hrefi =s hi P htotal Where ΔP hrefi represents the power allocated to the heating device in the ith stack unit in the alkali solution electrolyzer module; σ hi represents the heating balance factor of the heating device in the ith stack unit in the alkali solution electrolyzer module, P eli represents the power of the stack in the ith stack unit in the alkali liquid electrolyzer module, N is the total number of stack units in the alkali liquid electrolyzer module; P htotal Indicates the total heating power, P total Indicates the total power input to the alkali electrolyzer module, Represents the total electrolysis power.

7. The temperature balance control method of the parallel configuration alkaline solution electrolyzer module of the battery stack according to claim 1 is characterized in that: The alkaline liquid electrolyzer module comprises two sets of communication lines, namely, an internal communication line between the internal battery stacks of the alkaline liquid electrolyzer module and an external communication line between the alkaline liquid electrolyzer modules.

8. The temperature balance control method of the parallel configuration alkaline solution electrolyzer module of the battery stack according to claim 7 is characterized in that: The information transmitted by the internal communication line between the internal stacks of the alkaline solution electrolyzer module is the temperature of each stack; The information transmitted by the external communication line between the alkaline solution electrolyzer modules is the total power input into the alkaline solution electrolyzer modules.

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