Harmonic injection control method and device, hydrogen production power supply and hydrogen production system

Abstract

The invention discloses a harmonic injection control method and device, a hydrogen production power supply and a hydrogen production system, and belongs to the technical field of power electronics. The method comprises the following steps: acquiring real-time monitoring data and historical monitoring data obtained by monitoring an electrolytic cell of the hydrogen production system; according to the real-time monitoring data and the historical monitoring data, determining a plurality of frequency points of the injected current harmonics and the harmonic amplitude of each frequency point; extracting a current harmonic component of each frequency point in a direct-current output current of a hydrogen production power supply of the hydrogen production system according to the plurality of frequency points of the injected current harmonics; calculating a harmonic phase angle of each frequency point according to a plurality of frequency points of the injected current harmonic waves; and according to the plurality of frequency points, the harmonic amplitude of each frequency point, the current harmonic component of each frequency point and the harmonic phase angle of each frequency point, carrying out closed-loop control on harmonic injection of the direct-current output current of the hydrogen production power supply. According to the invention, closed-loop control of multi-frequency harmonic injection is realized, and the hydrogen production efficiency and the overall energy efficiency of the hydrogen production system are improved.

Description

Technical Field

[0001] This application belongs to the field of hydrogen energy manufacturing technology, and in particular relates to a harmonic injection control method, device, hydrogen production power supply and hydrogen production system. Background Technology

[0002] Traditional single-power sources often struggle to meet the dual requirements of power and stability in large-scale hydrogen production systems. Multi-unit parallel output technology, due to its excellent scalability and reliability, is considered an effective way to solve the power supply problems of high-power hydrogen production systems. However, achieving precise synchronization control and harmonic management during parallel output has become a key bottleneck in technological development. Harmonic injection has proven to effectively improve electrolysis efficiency and hydrogen production, but inappropriate harmonic frequencies and amplitudes can negatively impact the electrolyzer, such as increasing electrode corrosion or reducing overall system efficiency. Summary of the Invention

[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a harmonic injection control method, apparatus, hydrogen production power supply, and hydrogen production system, which optimizes the operation of the hydrogen production system and ensures stable operation and efficient hydrogen production.

[0004] In a first aspect, this application provides a harmonic injection control method, including:

[0005] Acquire real-time and historical monitoring data from the electrolyzers of the hydrogen production system;

[0006] Based on the real-time monitoring data and historical monitoring data, multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point are determined.

[0007] Based on the multiple frequency points of the injected current harmonics, the current harmonic components at each frequency point in the DC output current of the hydrogen production power supply of the hydrogen production system are extracted.

[0008] Calculate the harmonic phase angle at each frequency point based on the multiple frequency points of the injected current harmonics;

[0009] Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, the harmonic injection of the DC output current of the hydrogen production power supply is controlled in a closed loop.

[0010] In the above technical solution, based on real-time and historical monitoring data of the electrolyzer in the hydrogen production system, multiple frequency points of the harmonics of the injection current required by the electrolyzer in the hydrogen production system and the harmonic amplitude of each frequency point are determined. Then, based on these frequency points, the harmonic components of the corresponding frequencies are extracted from the DC output current of the hydrogen production power source, and the corresponding harmonic phase angles are calculated based on these frequency points. Using this data, closed-loop control of the harmonic injection of the DC output current of the hydrogen production power source is implemented, realizing closed-loop control of multi-frequency harmonic injection. At the same time, the parameters of the injected harmonics can be adjusted in real time according to the current state of the hydrogen production system, so that the electrolysis process is carried out at the optimal operating point, thereby optimizing the electrolysis process and improving the hydrogen production efficiency and overall energy efficiency of the hydrogen production system.

[0011] According to one embodiment of this application, determining multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point based on the real-time monitoring data and historical monitoring data includes:

[0012] Within a preset frequency range, the frequency of the injected current harmonics is gradually changed in a step manner, and based on the real-time monitoring data and historical monitoring data, the top N frequency points that are most effective in improving the electrolysis efficiency and hydrogen production of the hydrogen production system are determined as multiple frequency points of the injected current harmonics.

[0013] For each of the aforementioned frequency points, the harmonic amplitude is adjusted, and based on the real-time monitoring data and historical monitoring data, the harmonic amplitude that minimizes the energy consumption and optimizes the hydrogen production efficiency of the hydrogen production system at the current frequency point is determined and used as the harmonic amplitude for each of the aforementioned frequency points.

[0014] In the above technical solution, by performing step-by-step frequency adjustments within a preset frequency range, and combining real-time monitoring and historical data, N frequency points that most significantly improve the electrolysis efficiency and hydrogen production of the hydrogen production system are selected as multiple frequency points for the injected current harmonics. For each selected frequency point, the harmonic amplitude is further optimized until the state of lowest energy consumption and optimal hydrogen production efficiency of the hydrogen production system at that frequency is reached. Thus, the optimal harmonic amplitude for each frequency point is determined. An intelligent adjustment mechanism is adopted to adjust the frequency and amplitude of the harmonics in real time according to the current state of the hydrogen production system, so that the electrolysis process is carried out at the optimal operating point, thereby optimizing the electrolysis process, improving hydrogen production and energy utilization efficiency, providing data support for the realization of harmonic injection, and enabling harmonic injection to be effectively implemented.

[0015] According to one embodiment of this application, the step of extracting the current harmonic components at each frequency point of the DC output current of the hydrogen production power supply of the hydrogen production system based on multiple frequency points of the injected current harmonics includes:

[0016] The total harmonics of the DC output current are extracted using a high-pass filter;

[0017] Based on the total harmonics of the DC output current and multiple frequency points of the injected current harmonics, the α-axis and β-axis components of the current harmonics at each frequency point in the DC output current in the two-phase stationary coordinate system are calculated using multiple dual generalized second-order integrators.

[0018] In the above technical solution, based on multiple frequency points of the injected current harmonics, the total harmonic component is extracted from the DC output current of the hydrogen production system using a high-pass filter. Then, combining these frequency points, multiple dual generalized second-order integrators are used to calculate and extract the current harmonic components of each frequency point in the DC output current in a two-phase stationary coordinate system. This achieves harmonic component extraction, providing data support for harmonic injection and enabling its effective implementation.

[0019] According to one embodiment of this application, calculating the harmonic phase angle of each frequency point based on the plurality of frequency points of the injected current harmonics includes:

[0020] The harmonic phase angle of the first frequency point among the plurality of frequency points is calculated using the following formula:

[0021]

[0022] Where θ1 is the harmonic phase angle at the first frequency point, and f1 is the first frequency point. ΔT is the initial phase angle of the current harmonics, and ΔT is the sampling period.

[0023] Based on the harmonic phase angle θ1 of the first frequency point, the harmonic phase angles of all other frequency points besides the first frequency point are calculated using the following formula:

[0024] θ N =2π(f N -f1)ΔT+θ1

[0025] Where, θ N f is the harmonic phase angle at the Nth frequency point. N This is the Nth frequency point.

[0026] In the above technical solution, the harmonic phase angle of the first frequency point among multiple frequency points of the injected current harmonics is calculated, and then the harmonic phase angles of other frequency points are calculated based on the frequency and harmonic phase angle of the first frequency point, so that subsequent harmonic injection can be effectively implemented.

[0027] According to one embodiment of this application, the hydrogen production power supply adopts a multi-machine parallel output technology. One power unit is selected from the hydrogen production power supply as the master unit, and the remaining power units are as slave units. The master unit calculates the harmonic phase angle of a first frequency point and uploads the harmonic phase angle of the first frequency point to a first communication bus. Each slave unit verifies the harmonic phase angle of the first frequency point it has calculated locally based on the harmonic phase angle of the first frequency point received from the first communication bus. If they are inconsistent, the slave unit corrects the harmonic phase angle of the first frequency point it has calculated locally.

[0028] In the above technical solution, by selecting the master unit to calculate the harmonic phase angle of the first frequency point and uploading it to the first communication bus in the hydrogen production power supply using multi-machine parallel technology, and the slave unit receives and verifies the phase angle, and corrects it if there is a difference, so that each power unit can maintain phase consistency when injecting harmonics to avoid mutual interference. This realizes the coordinated work and efficient operation of the entire hydrogen production power supply, optimizes the overall performance of the hydrogen production system, and can improve the stability and reliability of high-power hydrogen production systems in large-scale applications.

[0029] According to one embodiment of this application, the closed-loop control of harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points, the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point includes:

[0030] Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic components of each frequency point, and the harmonic phase angle of each frequency point, a proportional resonant controller based on the current harmonics of each frequency point performs closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply; or...

[0031] Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic components of each frequency point, and the harmonic phase angle of each frequency point, a proportional-integral controller based on the current harmonics of each frequency point performs closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply.

[0032] In the above technical solution, the harmonic injection of the DC output current of the hydrogen production power supply is controlled in a closed loop using a proportional resonant controller or a proportional-integral controller, based on the required frequency points of the injected harmonic current, as well as the corresponding harmonic amplitude, harmonic components, and phase angle. During the control process, the parameters of the multi-frequency harmonic injection are adjusted according to the real-time monitored energy consumption and hydrogen production data of the hydrogen production system, which improves the system response speed and adjustment accuracy, as well as the system stability and hydrogen production efficiency.

[0033] According to one embodiment of this application, the step of performing closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points, the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, and the proportional resonant controller based on the current harmonics of each frequency point, includes:

[0034] Based on the harmonic amplitude and harmonic phase angle at each frequency point, calculate the given value of the injected current harmonic at each frequency point.

[0035] The given value of the injected current harmonic at each frequency point is subtracted from the α-axis component of the current harmonic at each frequency point in the two-phase stationary coordinate system, and the resulting difference is input into the proportional resonant controller of the current harmonic at each frequency point.

[0036] The output of the proportional resonant controller for the current harmonics at each frequency point is superimposed with the modulation signal output of the inductor current inner loop controller of the hydrogen production power supply, and intersected with the triangular carrier signal to obtain the PWM duty cycle signal for driving the power switch of the hydrogen production power supply.

[0037] In the above technical solution, the given value of the injected current harmonic is calculated based on the harmonic amplitude and phase angle at each frequency point. The difference between the given value and the α-axis component of the current harmonic in the two-phase stationary coordinate system is calculated, and the difference is input to the proportional resonant controller at the corresponding frequency point for processing. The output of the proportional resonant controller is superimposed with the modulation signal of the inductor current inner loop controller, and the duty cycle signal for driving the power switch is generated through PWM modulation to drive the power switch of the hydrogen production power supply. This realizes closed-loop control of the DC output current harmonic injection of the hydrogen production power supply, improves the system response speed and adjustment accuracy, and enhances the overall performance while ensuring stable system operation.

[0038] According to one embodiment of this application, the step of performing closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points, the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, and the proportional-integral controller based on the current harmonics of each frequency point, includes:

[0039] Based on the harmonic phase angle at each frequency point, and the α-axis and β-axis components of the current harmonics at each frequency point in the two-phase stationary coordinate system, Park transformation is performed to obtain the active and reactive components of the current harmonics at each frequency point.

[0040] The difference between the harmonic amplitude at each frequency point and the active component of the current harmonic at each frequency point is calculated, and the difference is input into the proportional-integral controller of the current harmonic at each frequency point.

[0041] The proportional-integral controller output of the current harmonics at each frequency point is subjected to Clarke inverse transformation based on the harmonic phase angle at each frequency point to obtain the α-axis control quantity of the current harmonics at each frequency point.

[0042] The α-axis control quantity of the current harmonics at each frequency point is superimposed with the modulation signal output by the inner loop controller of the inductor current of the hydrogen production power supply, and intersected with the triangular carrier signal to obtain the PWM duty cycle signal for driving the power switch of the hydrogen production power supply.

[0043] In the above technical solution, the current harmonics at each frequency point are transformed from the two-phase stationary coordinate system to active and reactive components through Park transformation. Then, the difference between the harmonic amplitude and the active component is input into a proportional-integral controller for closed-loop regulation. The output of the proportional-integral controller is then subjected to Clarke inverse transformation to obtain the α-axis control quantity at each frequency point. These control quantities are superimposed on the modulation signal of the inductor current inner loop controller, and finally intersected with the triangular carrier signal to generate a PWM duty cycle signal to drive the power switching transistor of the hydrogen production power supply. This achieves closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply, improves the system response speed and regulation accuracy, and enhances the overall performance while ensuring stable system operation.

[0044] Secondly, this application provides a harmonic injection control device, the device comprising:

[0045] The data monitoring module is used to acquire real-time and historical monitoring data obtained from monitoring the electrolyzers of the hydrogen production system.

[0046] The current harmonic frequency and amplitude generation module is used to determine multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point based on the real-time monitoring data and historical monitoring data.

[0047] The current harmonic component extraction module is used to extract the current harmonic components at each frequency point of the DC output current of the hydrogen production power supply of the hydrogen production system based on multiple frequency points of the injected current harmonics.

[0048] The current harmonic phase angle generation module is used to calculate the harmonic phase angle of each frequency point based on the multiple frequency points of the injected current harmonics.

[0049] The current harmonic injection closed-loop control module is used to perform closed-loop control on the harmonic injection of the DC output current of the hydrogen production power source based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point.

[0050] In the above technical solution, the harmonic injection control device determines multiple frequency points of the required injection current harmonics and the harmonic amplitude of each frequency point based on real-time and historical monitoring data of the hydrogen production system electrolyzer. Then, based on these frequency points, it extracts the corresponding frequency harmonic components from the DC output current of the hydrogen production power source and calculates the corresponding harmonic phase angle. Using this data, it implements closed-loop control of the harmonic injection of the DC output current of the hydrogen production power source, realizing closed-loop control of multi-frequency harmonic injection. At the same time, it can adjust the parameters of the injected harmonics in real time according to the current state of the hydrogen production system, so that the electrolysis process is carried out at the optimal operating point, thereby optimizing the electrolysis process and improving the hydrogen production efficiency and overall energy efficiency of the hydrogen production system.

[0051] Thirdly, this application provides a hydrogen production power source, comprising: multiple power supply units connected in parallel, each power supply unit including the current harmonic component extraction module, the current harmonic phase angle generation module and the current harmonic injection closed-loop control module in the harmonic injection control device as described in the second aspect, wherein the multiple power supply units work together through a first communication bus.

[0052] Fourthly, this application provides a hydrogen production system, characterized in that it includes a hydrogen production power source and an electrolyzer as described in the third aspect. The hydrogen production system further includes the data monitoring module in the harmonic injection control device as described in the second aspect, and the current harmonic frequency and amplitude generation module. The data monitoring module and the current harmonic frequency and amplitude generation module are connected through a first communication bus, and the current harmonic frequency and amplitude generation module and each power supply unit of the hydrogen production power source are connected through a second communication bus.

[0053] Fifthly, this application provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the harmonic injection control method as described in the first aspect above.

[0054] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0055] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0056] Figure 1 This is a schematic flowchart of a harmonic injection control method provided in some embodiments of this application;

[0057] Figure 2 This is a schematic diagram of extracting current harmonic components at various frequency points in the DC output current according to some embodiments of this application;

[0058] Figure 3 This is a schematic diagram illustrating the calculation of harmonic phase angles at various frequency points provided in some embodiments of this application;

[0059] Figure 4 This is a schematic diagram of a proportional resonant controller based on the current harmonics at each of the frequency points, according to some embodiments of this application, performing closed-loop control of harmonic injection;

[0060] Figure 5 This is a schematic diagram of a proportional-integral controller based on the current harmonics at each of the aforementioned frequency points, used for closed-loop control of harmonic injection, according to some embodiments of this application.

[0061] Figure 6 This is a schematic diagram of the structure of a harmonic injection control device provided in some embodiments of this application;

[0062] Figure 7 This is a schematic diagram of the structure of a hydrogen production system provided in some embodiments of this application.

[0063] Explanation of reference numerals in the attached figures:

[0064] 600: Harmonic injection control device;

[0065] 601: Data monitoring module; 602: Current harmonic frequency and amplitude generation module;

[0066] 603: Current harmonic component extraction module; 604: Current harmonic phase angle generation module;

[0067] 605: Current harmonic injection closed-loop control module. Detailed Implementation

[0068] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0069] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0070] Against the backdrop of the green energy transition, hydrogen energy, as a clean and efficient energy carrier, is playing an increasingly important role in the energy structure. Water electrolysis for hydrogen production, as a key pathway to achieve hydrogen production, directly impacts the production cost and future widespread application of hydrogen energy due to its efficiency and stability. As hydrogen production technology transitions to large-scale production, existing power supply solutions face significant challenges in terms of power scalability, energy efficiency, and system stability. Particularly in power management and optimization, an innovative solution is urgently needed to meet the demands for high-efficiency and large-scale hydrogen production.

[0071] In a hydrogen production system, the role of the hydrogen power source is to efficiently and stably convert the input electrical energy (which may come from the AC power grid, solar photovoltaic panels, or other energy sources) into DC electrical energy suitable for water electrolysis to produce hydrogen. The main circuit topologies include DC / DC converters and AC / DC converters.

[0072] Traditional single power supplies often struggle to meet the dual requirements of power and stability in large-scale hydrogen production systems. Multi-unit parallel output technology, due to its excellent scalability and reliability, is considered an effective way to solve the power supply problems of high-power hydrogen production systems.

[0073] When high-power power supplies are connected in parallel with multiple outputs, carrier synchronization between the MCU controllers (preferably DSP chips) of each parallel unit is crucial. Carrier synchronization is typically achieved by linking the MCU clocks or carrier generation mechanisms of each parallel unit, ensuring they generate carriers at the same frequency and phase. This improves the stability of the entire parallel system and the consistency of the responses of each parallel unit when the output load changes dynamically.

[0074] However, achieving precise synchronization control and harmonic management during parallel output has become a key bottleneck in technological development. Harmonic injection has been proven to effectively improve electrolysis efficiency and hydrogen production, but at the same time, inappropriate harmonic frequencies and amplitudes may have negative effects on the electrolyzer, such as increasing electrode corrosion or reducing overall system efficiency.

[0075] The presence of harmonics has both advantages and disadvantages for electrolyzers: on the one hand, appropriate harmonics can increase turbulence at the electrolysis interface, promoting rapid bubble detachment and thus improving electrolysis efficiency; on the other hand, inappropriate harmonic frequencies and amplitudes may lead to increased energy consumption during electrolysis and even damage the long-term stability of the electrolyzer. Therefore, precisely controlling the injection of harmonics has become crucial for improving the efficiency of hydrogen production through water electrolysis.

[0076] To address the aforementioned technical problems, embodiments of this application provide a harmonic injection control method, apparatus, hydrogen production power supply, and hydrogen production system. The following detailed description, in conjunction with the accompanying drawings, provides specific embodiments and their application scenarios.

[0077] The harmonic injection control method provided in this application embodiment can be executed by an electronic device or a functional module or entity in an electronic device that can implement the harmonic injection control method. The electronic devices mentioned in this application embodiment include, but are not limited to, controllers or processors in hydrogen production power supplies, controllers or processors or servers in hydrogen production systems, etc. The harmonic injection control method provided in this application embodiment is described below using an electronic device as the execution subject as an example.

[0078] Figure 1 This is a flowchart illustrating a harmonic injection control method provided in some embodiments of this application. For example... Figure 1 As shown, the harmonic injection control method includes steps 110, 120, 130, 140, and 150.

[0079] Step 110: Obtain real-time monitoring data and historical monitoring data obtained by monitoring the electrolyzer of the hydrogen production system.

[0080] Real-time monitoring data and historical monitoring data contain detailed information on the current and past operating status of the electrolyzer in the hydrogen production system. These data can be collected by sensors installed in the electrolyzer or related equipment in the hydrogen production system. They include key parameters of the electrolyzer itself and the electrolysis environment, such as electrolyzer energy consumption, hydrogen production, electrolyte temperature, electrolysis current, and voltage. These data are processed and analyzed to provide data support for subsequent steps. This data provides the basis for adaptive adjustment of the frequency and amplitude of the injected current harmonics.

[0081] Step 120: Based on the real-time monitoring data and historical monitoring data, determine multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point.

[0082] Harmonic injection refers to the process of adding harmonic currents with specific frequencies, amplitudes, and phase angles to the DC output current of the hydrogen production power source in a hydrogen production system. This technology is commonly used to improve the electrolysis efficiency and hydrogen production rate of hydrogen production systems.

[0083] The frequency points of the injected current harmonics refer to the frequency values ​​of the harmonic current that need to be injected into the DC output current of the hydrogen production power source. These frequency points are determined based on real-time and historical monitoring data of the electrolyzer in the hydrogen production system. The frequency points of the injected current harmonics can be determined based on monitoring data of the hydrogen production system, harmonic suppression requirements, or optimization objectives. For example, the frequency points of the injected current harmonics are multiple frequency points of the injected current harmonics that are most effective in improving electrolysis efficiency and hydrogen production.

[0084] The harmonic amplitude at a frequency point refers to the harmonic amplitude determined based on the frequency points of each injected current harmonic as specified above. These amplitudes can also be set based on hydrogen production system monitoring data, harmonic suppression requirements, or optimization objectives. For example, the harmonic amplitude at a frequency point is the harmonic amplitude that maximizes hydrogen production efficiency and minimizes energy consumption at the corresponding frequency. The magnitude of the harmonic amplitude directly affects the effectiveness of harmonic injection and its impact on the performance of the hydrogen production system.

[0085] Step 130: Based on the multiple frequency points of the injected current harmonics, extract the current harmonic components at each frequency point in the DC output current of the hydrogen production power supply of the hydrogen production system.

[0086] The harmonic components of current at specific frequency points refer to the actual current components with the same frequency as the injected harmonics in the DC output current of the hydrogen production power supply in a hydrogen production system. In harmonic injection control, these harmonic components need to be extracted for closed-loop control of harmonic injection into the DC output current of the hydrogen production power supply.

[0087] Step 140: Calculate the harmonic phase angle of each frequency point based on the multiple frequency points of the injected current harmonics.

[0088] In harmonic injection control, it is also necessary to determine the phase angle of the injected current harmonic at the corresponding frequency point. Specifically, it can be determined based on multiple frequency points of the injected current harmonic and the initial phase angle of the current harmonic.

[0089] Step 150: Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, perform closed-loop control on the harmonic injection of the DC output current of the hydrogen production power supply.

[0090] Hydrogen production power supplies typically employ a single-phase Buck converter circuit topology. However, in practical applications, other DC / DC converters, including single-phase Boost, multi-phase Buck, multi-phase Boost, phase-shifted full-bridge, and LLC resonant converters, are also applicable. The basic idea of ​​the harmonic injection dual-loop control method for Buck converters based on average current control is to compare the voltage setpoint Uref with the instantaneous feedback value of the output DC voltage Uo (voltage mode), or the current setpoint Iref with the instantaneous feedback value of the DC output current Io (current mode). The generated error signal, after passing through the outer loop controller, becomes the control quantity used as the setpoint Iref for the inner current loop. The difference between Iref and the instantaneous feedback value of the inductor current IL is modulated by the current loop controller. The output modulation signal intersects with the triangular carrier signal to obtain the duty cycle signal of the PWM pulse, thereby driving the power switching transistors in the hydrogen production power supply.

[0091] Based on the basic idea of ​​the above-mentioned dual closed-loop control method, the embodiments of this application perform closed-loop control on the harmonic injection of the DC output current of the hydrogen production power source according to the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point.

[0092] In the above technical solution, based on real-time and historical monitoring data of the electrolyzer in the hydrogen production system, multiple frequency points of the harmonics of the injection current required by the electrolyzer in the hydrogen production system and the harmonic amplitude of each frequency point are determined. Then, based on these frequency points, the harmonic components of the corresponding frequencies are extracted from the DC output current of the hydrogen production power source, and the corresponding harmonic phase angles are calculated based on these frequency points. Using this data, closed-loop control of the harmonic injection of the DC output current of the hydrogen production power source is implemented, realizing closed-loop control of multi-frequency harmonic injection. At the same time, the parameters of the injected harmonics can be adjusted in real time according to the current state of the hydrogen production system, so that the electrolysis process is carried out at the optimal operating point, thereby optimizing the electrolysis process and improving the hydrogen production efficiency and overall energy efficiency of the hydrogen production system.

[0093] In one embodiment of this application, determining multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point based on the real-time monitoring data and historical monitoring data includes:

[0094] Within a preset frequency range, the frequency of the injected current harmonics is gradually changed in a step manner, and based on the real-time monitoring data and historical monitoring data, the top N frequency points that are most effective in improving the electrolysis efficiency and hydrogen production of the hydrogen production system are determined as multiple frequency points of the injected current harmonics.

[0095] For each of the aforementioned frequency points, the harmonic amplitude is adjusted, and based on the real-time monitoring data and historical monitoring data, the harmonic amplitude that minimizes the energy consumption and optimizes the hydrogen production efficiency of the hydrogen production system at the current frequency point is determined and used as the harmonic amplitude for each of the aforementioned frequency points.

[0096] A preset frequency range refers to a set of frequency values ​​predetermined during the determination of the frequency of the injected current harmonics. The preset frequency range may be set based on the characteristics or design parameters of the hydrogen production system, or it may be set with reference to existing research or application experience with similar systems. Alternatively, the size of the preset frequency range may be adjusted according to specific objectives (such as improving electrolysis efficiency, increasing hydrogen production, or reducing energy consumption). When setting the preset frequency range, the lower limit is usually set relatively low to cover the frequency points of the injected current harmonics that are effective in improving the electrolysis efficiency and hydrogen production of the hydrogen production system.

[0097] In some embodiments, the lower limit of the preset frequency range is 50 Hz (power frequency).

[0098] The upper limit of the preset frequency range mainly depends on the following factors:

[0099] (1) Switching frequency of hydrogen production power supply: The highest harmonic frequency of the output of the PWM hydrogen production power supply is usually limited by its switching frequency. According to the Nyquist sampling theorem, the switching frequency needs to be at least twice the required output harmonic frequency in order to produce a sufficiently smooth waveform.

[0100] (2) MCU controller bandwidth and processing speed: The MCU controller used in the hydrogen production power supply needs to process input signals and execute control algorithms quickly to achieve rapid feedback regulation. A controller with a slow processing speed will limit its ability to output high-frequency harmonics. In addition, the controller bandwidth determines the highest frequency range that it can effectively track and output.

[0101] (3) Input and output filter design: Filters are used to smooth the output signal and reduce high-frequency noise, but their design must be able to allow the required harmonic frequencies to pass through while blocking signals that exceed that frequency. The higher the harmonic frequency, the greater the input and output ripple. Therefore, the highest harmonic frequency of the PWM hydrogen power supply output is limited by the filter cutoff frequency and the voltage and current stress of the filter capacitor.

[0102] Within a preset frequency range, the frequency of the injected current harmonics is gradually varied in increments (such as fixed Hz or kHz increments). At each frequency change, the impact on the hydrogen production system's performance is evaluated using real-time and historical monitoring data. This process determines the multiple injected current harmonic frequency points f1, f2, f3, ... f1 that are most effective in improving electrolysis efficiency and hydrogen production. N (Arranged in order from low frequency to high frequency).

[0103] Optionally, genetic algorithms and particle swarm optimization can be used to find the frequency point that is most effective in improving electrolysis efficiency and hydrogen production, or to find the frequency point with the lowest energy consumption and the highest hydrogen production. It is understandable that the highest hydrogen production means the most significant improvement in hydrogen production, and higher electrolysis efficiency means lower energy consumption.

[0104] For a selected frequency point, the harmonic amplitude at that frequency point is gradually adjusted, and the changes in the hydrogen production system are monitored in real time. By comparing the energy consumption and hydrogen production efficiency of the hydrogen production system under different harmonic amplitudes, the optimal harmonic amplitude at the current frequency point is determined, and thus multiple frequency points f1, f2, f3, ... f of the injection current harmonics are determined. N The corresponding harmonic amplitude I harm1set I harm2set I harm3set , ...I harmNset(N represents the sequence number of the injected current harmonic), the harmonic amplitude at each frequency point is the harmonic amplitude that minimizes the energy consumption and optimizes the hydrogen production efficiency of the hydrogen production system at that frequency point, or, is the harmonic amplitude that is most effective in improving electrolysis efficiency and hydrogen production at that frequency point.

[0105] In the above technical solution, by performing step-by-step frequency adjustments within a preset frequency range, and combining real-time monitoring and historical data, N frequency points that most significantly improve the electrolysis efficiency and hydrogen production of the hydrogen production system are selected as multiple frequency points for the injected current harmonics. For each selected frequency point, the harmonic amplitude is further optimized until the state of lowest energy consumption and optimal hydrogen production efficiency of the hydrogen production system at that frequency is reached. Thus, the optimal harmonic amplitude for each frequency point is determined. An intelligent adjustment mechanism is adopted to adjust the frequency and amplitude of the harmonics in real time according to the current state of the hydrogen production system, so that the electrolysis process is carried out at the optimal operating point, thereby optimizing the electrolysis process, improving hydrogen production and energy utilization efficiency, providing data support for the realization of harmonic injection, and enabling harmonic injection to be effectively implemented.

[0106] In one embodiment of this application, extracting the current harmonic components at each frequency point of the DC output current of the hydrogen production power supply of the hydrogen production system based on multiple frequency points of the injected current harmonics includes:

[0107] The total harmonics of the DC output current are extracted using a high-pass filter;

[0108] Based on the total harmonics of the DC output current and multiple frequency points of the injected current harmonics, the α-axis and β-axis components of the current harmonics at each frequency point in the DC output current in the two-phase stationary coordinate system are calculated using multiple dual generalized second-order integrators.

[0109] Multiple Second-Order Generalized Integrators (MSOGIs) are advanced filter techniques used in signal processing, particularly in power systems, to extract specific frequency components. They are based on the principles of Second-Order Generalized Integrators (SOGIs) but extended to process multiple frequency components simultaneously. An SOGI itself is a second-order filter capable of extracting signals of a specific frequency without phase shift while suppressing signals of other frequencies.

[0110] The two-phase stationary coordinate system, also known as the α-β coordinate system, is a commonly used coordinate transformation method in power systems. By transforming the voltage and current signals of a three-phase system (such as a three-phase motor or a three-phase power grid) onto two mutually perpendicular axes, the analysis and control process is simplified. These two axes are usually referred to as the α-axis and β-axis, and they have a specific angular relationship with the three phases of the three-phase system.

[0111] Figure 2 This is a schematic diagram illustrating the extraction of current harmonic components at various frequency points in the DC output current according to some embodiments of this application. For example... Figure 2 As shown, the DC output current I is obtained through a high-pass filter (HPF). o Total Harmonic I harm Extraction, wherein the high-pass filter allows frequencies above its cutoff frequency to pass through, thus it can be used to filter out current I. o The DC component is preserved, and its harmonic components are retained. The expression for the high-pass filter is:

[0112]

[0113] Where, ω c1 It is the cutoff angular frequency. The cutoff angular frequency setting value must be lower than the smallest harmonic frequency among the multiple frequency points of the injected current harmonics. s is the complex variable in the Laplace transform, and G... HPF (s) is the mathematical description of a high-pass filter in the S-domain (complex frequency domain), which determines the filter's response characteristics to signals of different frequencies.

[0114] In some embodiments, the cutoff angular frequency is set to 2π·10Hz.

[0115] Based on the total harmonic distortion (THD) of the DC output current extracted above, I harm And the current injection harmonic frequency points f1, f2, f3, ... f N The α-axis component I of the current harmonics at each frequency point in the DC output current in the two-phase stationary coordinate system is calculated using multiple second-order generalized integrators (MSOGI). harmNα and β-axis component I harmNβ .

[0116] In the above technical solution, based on multiple frequency points of the injected current harmonics, the total harmonic component is extracted from the DC output current of the hydrogen production system through a high-pass filter. Then, combined with these frequency points, the current harmonic components of each frequency point in the DC output current in the two-phase stationary coordinate system are calculated and extracted through multiple dual generalized second-order integrators. This realizes the extraction of harmonic components, provides data support for the realization of harmonic injection, and enables the effective implementation of harmonic injection.

[0117] In one embodiment of this application, calculating the harmonic phase angle of each frequency point based on the plurality of frequency points of the injected current harmonics includes:

[0118] The harmonic phase angle of the first frequency point among the plurality of frequency points is calculated using the following formula:

[0119]

[0120] Where θ1 is the harmonic phase angle at the first frequency point, and f1 is the first frequency point. ΔT is the initial phase angle of the current harmonics, and ΔT is the sampling period.

[0121] Based on the harmonic phase angle θ1 of the first frequency point, the harmonic phase angles of all other frequency points besides the first frequency point are calculated using the following formula:

[0122] θ N =2π(f N -f1)ΔT+θ1

[0123] Where, θ N f is the harmonic phase angle at the Nth frequency point. N This is the Nth frequency point.

[0124] Figure 3 This is a schematic diagram illustrating the calculation of harmonic phase angles at various frequency points, provided in some embodiments of this application. For example... Figure 3 As shown, for the multiple frequency points f1, f2, f3, ... f of the injected current harmonics N The first frequency point f1 is selected for priority harmonic phase angle calculation, yielding the corresponding harmonic phase angle θ1. This first frequency point is then used as the reference frequency point. Based on the reference frequency point f1 and the harmonic phase angle θ1, the phase angles θ2, θ3, ..., θ1 at other frequency points are calculated. N .

[0125] In the above technical solution, the harmonic phase angle of the first frequency point among multiple frequency points of the injected current harmonics is calculated, and then the harmonic phase angles of other frequency points are calculated based on the frequency and harmonic phase angle of the first frequency point, so that subsequent harmonic injection can be effectively implemented.

[0126] In one embodiment of this application, the hydrogen production power supply adopts a multi-machine parallel output technology. One power unit is selected from the hydrogen production power supply as the master unit, and the remaining power units are used as slave units. The master unit calculates the harmonic phase angle of a first frequency point and uploads the harmonic phase angle of the first frequency point to a first communication bus. Each slave unit verifies the harmonic phase angle of the first frequency point it has calculated locally based on the harmonic phase angle of the first frequency point received from the first communication bus. If they are inconsistent, the slave unit corrects the harmonic phase angle of the first frequency point it has calculated locally.

[0127] The hydrogen production power supply employs a multi-unit parallel output technology, meaning multiple power units operate simultaneously to provide the required power output. Among these power units, one is selected as the master unit, and the rest act as slave units. Both the master and slave units calculate the harmonic phase angles at various frequency points.

[0128] The master unit calculates the harmonic phase angle at the first frequency point and uploads it to the first communication bus. Each slave unit receives the harmonic phase angle from the master unit on the first communication bus and compares it with its locally calculated harmonic phase angle. If the harmonic phase angle calculated locally by the slave unit is inconsistent with the received harmonic phase angle, it is considered that the local calculation result may have an error. The slave unit will then correct its calculation result based on the received harmonic phase angle from the master unit, thereby ensuring that all power units achieve consistency in the harmonic phase angle at the first frequency point. Furthermore, since the harmonic phase angles at other frequencies are calculated based on the harmonic phase angle of the first frequency point, each power unit can maintain phase consistency when injecting harmonics at multiple frequencies, avoiding mutual interference and facilitating the coordinated operation and efficient output of the entire hydrogen production power supply.

[0129] For example, while the host calculates the harmonic phase angle θ1 corresponding to frequency point f1, it uploads the result to the first communication bus; the slave also calculates the harmonic phase angle θ1 locally and verifies its locally calculated harmonic phase angle θ1 based on the host's phase angle θ1 received on the first communication bus. If the verification is inconsistent with the host's, the slave corrects its locally calculated phase angle θ1.

[0130] It should be noted that the first communication bus is the communication channel between power supply units. It is a high-speed communication bus responsible for the transmission of real-time data, such as parameters like current, voltage, and phase angle. It is used to synchronize the control of each power supply unit, enabling different units to work together, match load requirements, achieve dynamic current sharing in response to load changes, and quickly respond to power supply faults. This realizes information exchange and synchronization between power supply units.

[0131] In the above technical solution, by selecting the master unit to calculate the harmonic phase angle of the first frequency point and uploading it to the first communication bus in the hydrogen production power supply using multi-machine parallel technology, and the slave unit receives and verifies the phase angle, and corrects it if there is a difference, so that each power unit can maintain phase consistency when injecting harmonics to avoid mutual interference. This realizes the coordinated work and efficient operation of the entire hydrogen production power supply, optimizes the overall performance of the hydrogen production system, and can improve the stability and reliability of high-power hydrogen production systems in large-scale applications.

[0132] In one embodiment of this application, the closed-loop control of harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points, the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point includes:

[0133] Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic components of each frequency point, and the harmonic phase angle of each frequency point, a proportional resonant controller based on the current harmonics of each frequency point performs closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply; or...

[0134] Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic components of each frequency point, and the harmonic phase angle of each frequency point, a proportional-integral controller based on the current harmonics of each frequency point performs closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply.

[0135] In this embodiment, for the harmonic injection of the DC output current of the hydrogen production power supply, based on multiple frequency points and their corresponding harmonic amplitudes, current harmonic components and harmonic phase angles, a proportional resonant controller or a proportional integral controller for the current harmonics at each frequency point is used for closed-loop control, which can achieve the goal of precise control of the injected current harmonics at each frequency point in the DC output current of the hydrogen production power supply.

[0136] It should be noted that the PR proportional resonant controller can provide infinite gain at its resonant frequency, effectively suppressing steady-state errors and thus achieving closed-loop tracking of the AC reference signal. The advantage of the PR proportional resonant controller lies in its lack of complex coordinate transformations and low computational cost. However, the PR proportional resonant controller places high demands on the bandwidth and sampling frequency of the control target. This requirement is even more pronounced in applications where the control target contains high-frequency harmonic components or has a wide frequency range. High-power hydrogen production power supplies typically have low switching and sampling frequencies, which may limit the performance of the PR proportional resonant controller in terms of control accuracy and stability.

[0137] The implementation of a proportional-integral (PI) controller is relatively simple, with good stability and a wide adjustment range, making it suitable for power supplies of various power levels and achieving good steady-state and dynamic performance. However, when controlling harmonics at multiple frequency points, the PI controller may require complex coordinate transformations and the use of multiple controllers, leading to a large computational load and a cumbersome parameter tuning process.

[0138] Therefore, selecting a suitable control scheme requires comprehensive consideration of the specific application requirements, desired control performance, and system design complexity. This necessitates balancing the advantages and disadvantages of both methods based on the specific characteristics and performance requirements of the hydrogen production system to determine the most suitable control strategy.

[0139] In some embodiments, the step of performing closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, and the proportional resonant controller based on the current harmonics of each frequency point, includes:

[0140] Based on the harmonic amplitude and harmonic phase angle at each frequency point, calculate the given value of the injected current harmonic at each frequency point.

[0141] The given value of the injected current harmonic at each frequency point is subtracted from the α-axis component of the current harmonic at each frequency point in the two-phase stationary coordinate system, and the resulting difference is input into the proportional resonant controller of the current harmonic at each frequency point.

[0142] The output of the proportional resonant controller for the current harmonics at each frequency point is superimposed with the modulation signal output of the inductor current inner loop controller of the hydrogen production power supply, and intersected with the triangular carrier signal to obtain the PWM duty cycle signal for driving the power switch of the hydrogen production power supply.

[0143] Figure 4 This is a schematic diagram illustrating closed-loop control of harmonic injection by a proportional resonant controller based on the current harmonics at each of the stated frequency points, provided in some embodiments of this application. For example... Figure 4 As shown, based on the current injection harmonic amplitude at each frequency point (i.e., the harmonic amplitude at each frequency point mentioned above) I harmNset And the current injection harmonic phase angle (i.e., the harmonic phase angle at each frequency point mentioned above) θ N Calculate the given value of the current-injected harmonics at each frequency point: I harmNref =I harmNset ·cosθ N Then, the current harmonic setpoint I at each frequency point is set respectively. harmNref With the α-axis component I of the current harmonics at each frequency point harmNαThe difference is calculated to adjust the PR proportional resonant controller at each frequency point. The output of the PR proportional resonant controller at each harmonic frequency point is superimposed with the modulation signal output of the inner loop PI proportional-integral controller of the hydrogen power supply inductor current, and intersected with the triangular carrier signal to obtain the PWM drive duty cycle signal of the power switch. The PWM signal directly controls the on and off of the power switch, controlling the DC output current of the hydrogen power supply, thereby achieving the goal of closed-loop control of the injected current harmonics at each frequency point in the DC output current of the hydrogen power supply.

[0144] The transfer function of the PR proportional resonant controller is:

[0145]

[0146] Among them, K p For proportional control of gain, K rN The gain is the resonant control gain, ω0 is the angular frequency at the harmonic frequency point, and ω c Let G be the resonant quality factor, s represent the complex variable in the Laplace transform, and G be the resonant quality factor. PR (s) represents the relationship between the input and output of the PR proportional resonant controller.

[0147] In the above technical solution, the given value of the injected current harmonic is calculated based on the harmonic amplitude and phase angle at each frequency point. The difference between the given value and the α-axis component of the current harmonic in the two-phase stationary coordinate system is calculated, and the difference is input to the proportional resonant controller at the corresponding frequency point for processing. The output of the proportional resonant controller is superimposed with the modulation signal of the inductor current inner loop controller, and the duty cycle signal for driving the power switch is generated through PWM modulation to drive the power switch of the hydrogen production power supply. This realizes closed-loop control of the DC output current harmonic injection of the hydrogen production power supply, improves the system response speed and adjustment accuracy, and enhances the overall performance while ensuring stable system operation.

[0148] In some embodiments, the step of performing closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, and the proportional-integral controller based on the current harmonics of each frequency point, includes:

[0149] Based on the harmonic phase angle at each frequency point, and the α-axis and β-axis components of the current harmonics at each frequency point in the two-phase stationary coordinate system, Park transformation is performed to obtain the active and reactive components of the current harmonics at each frequency point.

[0150] The difference between the harmonic amplitude at each frequency point and the active component of the current harmonic at each frequency point is calculated, and the difference is input into the proportional-integral controller of the current harmonic at each frequency point.

[0151] The proportional-integral controller output of the current harmonics at each frequency point is subjected to Clarke inverse transformation based on the harmonic phase angle at each frequency point to obtain the α-axis control quantity of the current harmonics at each frequency point.

[0152] The α-axis control quantity of the current harmonics at each frequency point is superimposed with the modulation signal output by the inner loop controller of the inductor current of the hydrogen production power supply, and intersected with the triangular carrier signal to obtain the PWM duty cycle signal for driving the power switch of the hydrogen production power supply.

[0153] The purpose of Park transform is to convert the current harmonic components from a two-phase stationary coordinate system (such as the α-β coordinate system) to a synchronous rotating coordinate system (dq coordinate system), thereby separating the active component (d-axis component) and reactive component (q-axis component) of the current harmonics at each frequency point.

[0154] The control signal output by the PI proportional-integral controller is based on a synchronous rotating coordinate system (dq coordinate system). In order to convert the control signal back to a two-phase stationary coordinate system (α-β coordinate system) and combine it with the actual modulation signal of the hydrogen production power supply, an inverse Clarke transformation is required.

[0155] Figure 5 This is a schematic diagram illustrating closed-loop control of harmonic injection by a proportional-integral controller based on the current harmonics at each of the stated frequency points, provided in some embodiments of this application. For example... Figure 5 As shown, based on the harmonic phase angle θ at each frequency point N and the α-axis component I of the current harmonics at each frequency point. harmNα and β-axis component I harmNβ Perform Park transform to obtain the active component I of the current harmonics at each frequency point. harmNd and reactive component I harmNq :

[0156]

[0157] Then, current at each frequency point is injected into the harmonic amplitude I. harmNset The active component I of the current harmonics at each frequency point harmNd The difference is calculated, and the PI proportional-integral controller is used to adjust the current harmonics at each frequency point. The output I of the PI proportional-integral controller at each frequency point is... harmNdOut Based on the phase θ of the current injection harmonic N Performing the Clarke inverse transform, we obtain the α-axis control quantity I of the current harmonics at each frequency point. harmNαOut :

[0158] I harmNαOut =I harmNdOut ·cosθ N -I harmNqOut ·sinθN

[0159] Due to the reactive component I of the current harmonics harmNq Not involved in closed-loop control, I harmNqOut =0, therefore the above formula can be simplified to:

[0160] I harmNαOut =I harmNdOut ·cosθ N

[0161] The α-axis control quantity I of the current harmonics at each frequency point harmNαOut The modulation signal of the output of the PI proportional-integral regulator in the inner loop of the hydrogen power supply inductor current is superimposed with the signal of the triangular carrier signal to obtain the PWM drive duty cycle signal of the power switch, thereby achieving the goal of closed-loop control of the injected current harmonics at each frequency point in the DC output current of the hydrogen power supply.

[0162] In the above technical solution, the current harmonics at each frequency point are transformed from the two-phase stationary coordinate system to active and reactive components through Park transformation. Then, the difference between the harmonic amplitude and the active component is input into a proportional-integral controller for closed-loop regulation. The output of the proportional-integral controller is then subjected to Clarke inverse transformation to obtain the α-axis control quantity at each frequency point. These control quantities are superimposed on the modulation signal of the inductor current inner loop controller, and finally intersected with the triangular carrier signal to generate a PWM duty cycle signal to drive the power switching transistor of the hydrogen production power supply. This achieves closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply, improves the system response speed and regulation accuracy, and enhances the overall performance while ensuring stable system operation.

[0163] The harmonic injection control method provided in this application can be executed by a harmonic injection control device. This application uses the example of a harmonic injection control device executing the harmonic injection control method to illustrate the harmonic injection control device provided in this application.

[0164] Figure 6 This is a schematic diagram of the structure of a harmonic injection control device provided in some embodiments of this application. For example... Figure 6 As shown, the harmonic injection control device 600 includes:

[0165] Data monitoring module 601 is used to acquire real-time monitoring data and historical monitoring data obtained from monitoring the electrolyzer of the hydrogen production system;

[0166] The current harmonic frequency and amplitude generation module 602 is used to determine multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point based on the real-time monitoring data and historical monitoring data.

[0167] The current harmonic component extraction module 603 is used to extract the current harmonic components of each frequency point in the DC output current of the hydrogen production power supply of the hydrogen production system based on the multiple frequency points of the injected current harmonics.

[0168] The current harmonic phase angle generation module 604 is used to calculate the harmonic phase angle of each frequency point based on the multiple frequency points of the injected current harmonics.

[0169] The current harmonic injection closed-loop control module 605 is used to perform closed-loop control on the harmonic injection of the DC output current of the hydrogen production power source based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point.

[0170] Optionally, the current harmonic frequency and amplitude generation module 602 is used for:

[0171] Within a preset frequency range, the frequency of the injected current harmonics is gradually changed in a step manner, and based on the real-time monitoring data and historical monitoring data, the top N frequency points that are most effective in improving the electrolysis efficiency and hydrogen production of the hydrogen production system are determined as multiple frequency points of the injected current harmonics.

[0172] For each of the aforementioned frequency points, the harmonic amplitude is adjusted, and based on the real-time monitoring data and historical monitoring data, the harmonic amplitude that minimizes the energy consumption and optimizes the hydrogen production efficiency of the hydrogen production system at the current frequency point is determined and used as the harmonic amplitude for each of the aforementioned frequency points.

[0173] Optionally, the current harmonic component extraction module 603 is used for:

[0174] The total harmonics of the DC output current are extracted using a high-pass filter;

[0175] Based on the total harmonics of the DC output current and multiple frequency points of the injected current harmonics, the α-axis and β-axis components of the current harmonics at each frequency point in the DC output current in the two-phase stationary coordinate system are calculated using multiple dual generalized second-order integrators.

[0176] Optionally, the current harmonic phase angle generation module 604 is used for:

[0177] The harmonic phase angle of the first frequency point among the plurality of frequency points is calculated using the following formula:

[0178]

[0179] Where θ1 is the harmonic phase angle at the first frequency point, and f1 is the first frequency point. ΔT is the initial phase angle of the current harmonics, and ΔT is the sampling period.

[0180] Based on the harmonic phase angle θ1 of the first frequency point, the harmonic phase angles of all other frequency points besides the first frequency point are calculated using the following formula:

[0181] θ N =2π(f N -f1)ΔT+θ1

[0182] Where, θ N f is the harmonic phase angle at the Nth frequency point. N This is the Nth frequency point.

[0183] Optionally, the current harmonic injection closed-loop control module 605 is used for:

[0184] Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic components of each frequency point, and the harmonic phase angle of each frequency point, a proportional resonant controller based on the current harmonics of each frequency point performs closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply; or...

[0185] Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic components of each frequency point, and the harmonic phase angle of each frequency point, a proportional-integral controller based on the current harmonics of each frequency point performs closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply.

[0186] Optionally, the current harmonic injection closed-loop control module 605 is used for:

[0187] Based on the harmonic amplitude and harmonic phase angle at each frequency point, calculate the given value of the injected current harmonic at each frequency point.

[0188] The given value of the injected current harmonic at each frequency point is subtracted from the α-axis component of the current harmonic at each frequency point in the two-phase stationary coordinate system, and the resulting difference is input into the proportional resonant controller of the current harmonic at each frequency point.

[0189] The output of the proportional resonant controller for the current harmonics at each frequency point is superimposed with the modulation signal output of the inductor current inner loop controller of the hydrogen production power supply, and intersected with the triangular carrier signal to obtain the PWM duty cycle signal for driving the power switch of the hydrogen production power supply.

[0190] Optionally, the current harmonic injection closed-loop control module 605 is used for:

[0191] Based on the harmonic phase angle at each frequency point, and the α-axis and β-axis components of the current harmonics at each frequency point in the two-phase stationary coordinate system, Park transformation is performed to obtain the active and reactive components of the current harmonics at each frequency point.

[0192] The difference between the harmonic amplitude at each frequency point and the active component of the current harmonic at each frequency point is calculated, and the difference is input into the proportional-integral controller of the current harmonic at each frequency point.

[0193] The proportional-integral controller output of the current harmonics at each frequency point is subjected to Clarke inverse transformation based on the harmonic phase angle at each frequency point to obtain the α-axis control quantity of the current harmonics at each frequency point.

[0194] The α-axis control quantity of the current harmonics at each frequency point is superimposed with the modulation signal output by the inner loop controller of the inductor current of the hydrogen production power supply, and intersected with the triangular carrier signal to obtain the PWM duty cycle signal for driving the power switch of the hydrogen production power supply.

[0195] In the above technical solution, the harmonic injection control device determines multiple frequency points of the harmonics of the injection current required by the hydrogen production system electrolyzer and the harmonic amplitude of each frequency point based on real-time and historical monitoring data of the hydrogen production system electrolyzer. Then, based on these frequency points, it extracts the corresponding harmonic components from the DC output current of the hydrogen production power source and calculates the corresponding harmonic phase angles. Using this data, it implements closed-loop control of the harmonic injection of the DC output current of the hydrogen production power source to achieve optimized system operation. At the same time, it can adjust the parameters of the injected harmonics in real time according to the current state of the hydrogen production system, so that the electrolysis process is carried out at the optimal operating point, thereby optimizing the electrolysis process and ensuring the stable operation and efficient hydrogen production of the hydrogen production system.

[0196] The harmonic injection control device in this embodiment includes a data monitoring module 601, a current harmonic frequency and amplitude generation module 602, a current harmonic component extraction module 603, a current harmonic phase angle generation module 604, and a current harmonic injection closed-loop control module 605. These modules can be implemented in software or hardware. When implemented in hardware, it can be implemented by a processor, which can include general-purpose processors, special-purpose processors, etc., such as central processing units (CPUs), microprocessors, digital signal processors (DSPs), artificial intelligence (AI) processors, graphics processing units (GPUs), application-specific integrated circuits (ASICs), network processors (NPs), field-programmable gate arrays (FPGAs), or other programmable logic devices, gate circuits, transistors, discrete hardware components, etc.

[0197] The harmonic injection control device provided in this application embodiment can realize the various processes implemented in the harmonic injection control method embodiment, and will not be described again here to avoid repetition.

[0198] In some embodiments, this application also provides a hydrogen production power source, including: a plurality of power supply units connected in parallel, each power supply unit including as follows: Figure 6 The current harmonic component extraction module, current harmonic phase angle generation module, and current harmonic injection closed-loop control module in the harmonic injection control device shown in the diagram work collaboratively among multiple power supply units via a first communication bus.

[0199] Hydrogen production power supplies convert input electrical energy (which may come from the AC grid, solar photovoltaic panels, or other energy sources) into DC power suitable for hydrogen production via water electrolysis. The main circuit topologies include DC / DC converters and AC / DC converters. To meet the application requirements of high-power, large-scale, and high-efficiency water electrolysis for hydrogen production, hydrogen production power supplies employ multi-unit parallel output technology. When multiple high-power power supplies are connected in parallel, carrier synchronization is required between the parallel power units. This ensures that different power units generate carrier waves at the same frequency and phase, thereby achieving stable operation and energy conversion of the multi-unit parallel system.

[0200] In the above technical solution, the hydrogen production power supply includes multiple power supply units connected in parallel. The multi-machine parallel output technology is adopted to improve the overall output capacity of the hydrogen production power supply, which can meet the hydrogen production needs of a larger scale. The first communication bus realizes the collaborative work between multiple power supply units, which improves the consistency of the response of each parallel unit when the output load changes dynamically, as well as the stability of the entire hydrogen production power supply.

[0201] In some embodiments, such as Figure 7 As shown in the illustration, this application also provides a hydrogen production system, including a hydrogen production power source, an electrolyzer, and other components such as... Figure 6 The data monitoring module and the current harmonic frequency and amplitude generation module in the harmonic injection control device shown are connected via a first communication bus, and the current harmonic frequency and amplitude generation module and each power supply unit of the hydrogen production power supply are connected via a second communication bus.

[0202] Among them, the first communication bus, as a high-speed communication bus, is responsible for the transmission of real-time data, such as parameters like current, voltage, and phase angle, and is used to synchronize the control of each parallel unit, enabling different units to work together, match load requirements, realize dynamic current sharing of load changes, and quickly respond to system faults.

[0203] The second communication bus, as a low-speed communication bus, is used to transmit non-real-time data, such as system status, alarms, fault diagnosis information, configuration parameters, and historical records. Communication methods support long-distance communication, including but not limited to CAN communication and serial SCI communication.

[0204] The data monitoring module collects key parameters of the electrolyzer and electrolysis environment in real time, such as electrolyzer energy consumption, hydrogen production, electrolyte temperature, electrolysis current and voltage, processes and analyzes them, and transmits the data in real time to the current harmonic frequency and amplitude generation module through the communication network.

[0205] The current harmonic frequency and amplitude generation module employs an adaptive harmonic injection algorithm. Through a multi-objective optimization (MOO) framework, it analyzes real-time monitoring data and historical data from the data monitoring module to automatically identify multiple frequency points f1, f2, f3, ... f of the injected current harmonics that are most effective in improving electrolysis efficiency and hydrogen production. N and the corresponding harmonic amplitude I harm1set I harm2set I harm3set , ...I harmNset It is then transmitted to multiple power supply units connected in parallel in the hydrogen production power source via a low-speed communication bus.

[0206] like Figure 7As shown, the hydrogen production power source includes power supply unit 1, power supply unit 2, ..., power supply unit N connected in parallel.

[0207] The current harmonic component extraction module in power supply unit i (i = 1, 2, ..., N) extracts the hydrogen production power supply DC output current I based on multiple frequency points and harmonic amplitude information of the injected current harmonics from the current harmonic frequency and amplitude generation module. o Harmonic components of current at various frequency points are extracted.

[0208] The current harmonic phase angle generation module in power supply unit i (i = 1, 2, ..., N) generates harmonic frequency points f1, f2, f3, ... f1 based on the harmonic frequency and amplitude generation modules. N Calculate the harmonic phase angles θ2, θ3, ..., θ at each frequency point. N .

[0209] One power supply unit is selected as the master, and the other power supply units are selected as slaves. While the master calculates the harmonic phase angle θ1 corresponding to frequency point f1, it uploads the result to the high-speed communication bus. The slaves also calculate the harmonic phase angle θ1 locally and verify their locally calculated harmonic phase angle θ1 against the master's phase angle θ1 received from the high-speed communication bus. If the verification result differs from the master's, the slave corrects its locally calculated phase angle θ1.

[0210] The current harmonic injection closed-loop module in power unit i (i = 1, 2, ..., N) generates the hydrogen production power supply DC output current I based on multiple frequency points and harmonic amplitude information of the injected current harmonics from the current harmonic frequency and amplitude generation module, and the current harmonic components at each frequency point output by the current harmonic extraction module. o Closed-loop control of injected harmonics at each frequency point.

[0211] The DC load switch is located between the hydrogen production power supply and the electrolyzer, used to control the circuit's on / off state and to inject harmonics into the DC output current I. o By introducing an electrolyzer, harmonic injection control in the electrolytic hydrogen production process is realized, optimizing the overall performance of the hydrogen production system and improving the stability and reliability of high-power hydrogen production systems in large-scale applications.

[0212] This application also provides a non-transitory computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the various processes of the above-described harmonic injection control method embodiments and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0213] The processor is the processor described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0214] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0215] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0216] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

[0217] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0218] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A harmonic injection control method, characterized in that, include: Acquire real-time and historical monitoring data from the electrolyzers of the hydrogen production system; Based on the real-time monitoring data and historical monitoring data, multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point are determined. Based on the multiple frequency points of the injected current harmonics, the current harmonic components at each frequency point in the DC output current of the hydrogen production power supply of the hydrogen production system are extracted. Calculate the harmonic phase angle at each frequency point based on the multiple frequency points of the injected current harmonics; Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, the harmonic injection of the DC output current of the hydrogen production power supply is controlled in a closed loop.

2. The harmonic injection control method according to claim 1, characterized in that, The step of determining multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point based on the real-time monitoring data and historical monitoring data includes: Within a preset frequency range, the frequency of the injected current harmonics is gradually changed in a step manner, and based on the real-time monitoring data and historical monitoring data, the top N frequency points that are most effective in improving the electrolysis efficiency and hydrogen production of the hydrogen production system are determined as multiple frequency points of the injected current harmonics. For each of the aforementioned frequency points, the harmonic amplitude is adjusted, and based on the real-time monitoring data and historical monitoring data, the harmonic amplitude that minimizes the energy consumption and optimizes the hydrogen production efficiency of the hydrogen production system at the current frequency point is determined and used as the harmonic amplitude for each of the aforementioned frequency points.

3. The harmonic injection control method according to claim 1, characterized in that, The step of extracting the current harmonic components at each frequency point of the DC output current of the hydrogen production power supply of the hydrogen production system based on multiple frequency points of the injected current harmonics includes: The total harmonics of the DC output current are extracted using a high-pass filter; Based on the total harmonics of the DC output current and multiple frequency points of the injected current harmonics, the α-axis and β-axis components of the current harmonics at each frequency point in the DC output current in the two-phase stationary coordinate system are calculated using multiple dual generalized second-order integrators.

4. The harmonic injection control method according to claim 1, characterized in that, The step of calculating the harmonic phase angle at each frequency point based on the multiple frequency points of the injected current harmonics includes: The harmonic phase angle of the first frequency point among the plurality of frequency points is calculated using the following formula: Where θ1 is the harmonic phase angle at the first frequency point, and f1 is the first frequency point. ΔT is the initial phase angle of the current harmonics, and ΔT is the sampling period. Based on the harmonic phase angle θ1 of the first frequency point, the harmonic phase angles of all other frequency points besides the first frequency point are calculated using the following formula: i N =2π(f N -f1)ΔT+θ1 Where, θ N f is the harmonic phase angle at the Nth frequency point. N This is the Nth frequency point.

5. The harmonic injection control method according to claim 4, characterized in that, The hydrogen production power supply adopts a multi-machine parallel output technology. One power unit is selected from the hydrogen production power supply as the master and the remaining power units are as slaves. The master calculates the harmonic phase angle of the first frequency point and uploads the harmonic phase angle of the first frequency point to the first communication bus. Each slave device verifies the harmonic phase angle of the first frequency point calculated locally based on the harmonic phase angle of the first frequency point received from the first communication bus. If they are inconsistent, the slave device corrects the harmonic phase angle of the first frequency point calculated locally.

6. The harmonic injection control method according to claim 1, characterized in that, The closed-loop control of harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points, the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point includes: Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic components of each frequency point, and the harmonic phase angle of each frequency point, a proportional resonant controller based on the current harmonics of each frequency point performs closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply; or... Based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic components of each frequency point, and the harmonic phase angle of each frequency point, a proportional-integral controller based on the current harmonics of each frequency point performs closed-loop control of the harmonic injection of the DC output current of the hydrogen production power supply.

7. The harmonic injection control method according to claim 6, characterized in that, The method of performing closed-loop control of harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points, the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, and the proportional resonant controller based on the current harmonics of each frequency point, includes: Based on the harmonic amplitude and harmonic phase angle at each frequency point, calculate the given value of the injected current harmonic at each frequency point. The given value of the injected current harmonic at each frequency point is subtracted from the α-axis component of the current harmonic at each frequency point in the two-phase stationary coordinate system, and the resulting difference is input into the proportional resonant controller of the current harmonic at each frequency point. The output of the proportional resonant controller for the current harmonics at each frequency point is superimposed with the modulation signal output of the inductor current inner loop controller of the hydrogen production power supply, and intersected with the triangular carrier signal to obtain the PWM duty cycle signal for driving the power switch of the hydrogen production power supply.

8. The harmonic injection control method according to claim 6, characterized in that, The step of performing closed-loop control of harmonic injection of the DC output current of the hydrogen production power supply based on the plurality of frequency points, the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point, and a proportional-integral controller based on the current harmonics of each frequency point, includes: Based on the harmonic phase angle at each frequency point, and the α-axis and β-axis components of the current harmonics at each frequency point in the two-phase stationary coordinate system, Park transformation is performed to obtain the active and reactive components of the current harmonics at each frequency point. The difference between the harmonic amplitude at each frequency point and the active component of the current harmonic at each frequency point is calculated, and the difference is input into the proportional-integral controller of the current harmonic at each frequency point. The proportional-integral controller output of the current harmonics at each frequency point is subjected to Clarke inverse transformation based on the harmonic phase angle at each frequency point to obtain the α-axis control quantity of the current harmonics at each frequency point. The α-axis control quantity of the current harmonics at each frequency point is superimposed with the modulation signal output by the inner loop controller of the inductor current of the hydrogen production power supply, and intersected with the triangular carrier signal to obtain the PWM duty cycle signal for driving the power switch of the hydrogen production power supply.

9. A harmonic injection control device, characterized in that, include: The data monitoring module is used to acquire real-time and historical monitoring data obtained from monitoring the electrolyzers of the hydrogen production system. The current harmonic frequency and amplitude generation module is used to determine multiple frequency points of the injected current harmonics and the harmonic amplitude of each frequency point based on the real-time monitoring data and historical monitoring data. The current harmonic component extraction module is used to extract the current harmonic components at each frequency point of the DC output current of the hydrogen production power supply of the hydrogen production system based on multiple frequency points of the injected current harmonics. The current harmonic phase angle generation module is used to calculate the harmonic phase angle of each frequency point based on the multiple frequency points of the injected current harmonics. The current harmonic injection closed-loop control module is used to perform closed-loop control on the harmonic injection of the DC output current of the hydrogen production power source based on the plurality of frequency points and the harmonic amplitude of each frequency point, the current harmonic component of each frequency point, and the harmonic phase angle of each frequency point.

10. A hydrogen production power source, comprising: Multiple power supply units are connected in parallel. Each power supply unit includes the current harmonic component extraction module, the current harmonic phase angle generation module, and the current harmonic injection closed-loop control module in the harmonic injection control device as described in claim 9. The multiple power supply units work together through a first communication bus.

11. A hydrogen production system, characterized in that, The hydrogen production power supply, electrolyzer, and hydrogen production system as described in claim 10 also include the data monitoring module and the current harmonic frequency and amplitude generation module in the harmonic injection control device as described in claim 9. The data monitoring module and the current harmonic frequency and amplitude generation module are connected through a first communication bus, and the current harmonic frequency and amplitude generation module and each power supply unit of the hydrogen production power supply are connected through a second communication bus.

12. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the harmonic injection control method as described in any one of claims 1-8.

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