A broadband injection electrolyzer impedance testing system and method

Abstract

This invention provides a broadband injection electrolyzer impedance testing system and method, relating to the field of electrolytic hydrogen production. The method includes: generating a multi-band composite perturbation signal, including perturbation signals of multiple discrete frequency bands; injecting the multi-band composite perturbation signal into the electrolyzer under test, acquiring real-time state data of the electrolyzer under test, and acquiring perturbation response data of the electrolyzer under test based on initial sampling parameters; repeatedly executing the process based on the real-time state data of the electrolyzer under test to generate real-time optimal sampling parameters and real-time optimal signal parameters, adjusting the multi-band composite perturbation signal according to the real-time optimal signal parameters, and acquiring perturbation response data of the electrolyzer under test according to the real-time optimal sampling parameters, until the impedance test is completed; generating spectral distribution data based on the acquired perturbation response data, and calculating the impedance data of the electrolyzer under test based on the spectral distribution data. This method has the advantage of achieving accurate measurement of electrolyzer impedance under dynamic operating conditions.

Description

Technical Field

[0001] This invention relates to the field of electrolytic hydrogen production, and in particular to a broadband injection electrolyzer impedance testing system and method. Background Technology

[0002] An electrolyzer is a core piece of equipment that uses electrical energy to drive a chemical reaction (electrolysis process), and it is widely used in industrial production, energy conversion, and materials preparation. Its basic principle is to use an external direct current (DC) to cause ions in the electrolyte solution or molten electrolyte to undergo a redox reaction on the electrode surface, thereby achieving the decomposition or synthesis of substances. Electrolytic hydrogen production is the process of decomposing water into hydrogen and oxygen through electrolysis. Specifically, DC is passed through an electrolyzer filled with electrolyte, and water molecules undergo an electrochemical reaction at the electrodes, decomposing into hydrogen and oxygen. Electrolytic hydrogen production can be widely used in various applications requiring hydrogen, including fuel cells, chemical raw materials, and energy storage. By converting other energy sources (such as solar and wind energy) into hydrogen energy for storage, energy storage and transportation problems can be effectively solved. The impedance of the electrolyzer is a key parameter reflecting its electrochemical performance and operating status; impedance measurement is crucial for optimizing processes, ensuring safety, and extending equipment lifespan.

[0003] Existing electrolytic cell impedance testing technologies lack real-time monitoring and rapid response capabilities under dynamic operating conditions, making it difficult to adapt to rapid changes in the electrolytic cell's operating status and failing to meet the requirements of efficient control. Furthermore, electrochemical impedance spectroscopy testing requires point-by-point frequency sweeping across a wide frequency range (e.g., 0.1Hz–10kHz), with a single complete measurement taking several minutes or even longer. This causes changes in the electrolytic cell's operating status during the measurement process, especially resulting in a significant decrease in data accuracy in the low-frequency range. Electrolytic cell impedance parameters change in real time during operation and are affected by multiple factors such as external environment, material aging, and operating conditions. Existing technologies struggle to accurately track these dynamic changes, leading to a mismatch between the impedance parameter model and actual operating conditions, thereby affecting the efficient operation of the electrolytic cell under voltage or current control modes.

[0004] Therefore, there is a need to provide a wideband electrolytic cell impedance testing system and method to achieve accurate measurement of electrolytic cell impedance under dynamic operating conditions. Summary of the Invention

[0005] This invention provides a broadband injection electrolytic cell impedance testing method, comprising: generating a multi-band composite disturbance signal, wherein the multi-band composite disturbance signal includes disturbance signals of multiple discrete frequency bands; injecting the multi-band composite disturbance signal into the electrolytic cell under test, acquiring real-time state data of the electrolytic cell under test, and acquiring disturbance response data of the electrolytic cell under test according to initial sampling parameters; repeatedly executing the process based on the real-time state data of the electrolytic cell under test to generate real-time optimal sampling parameters and real-time optimal signal parameters, adjusting the multi-band composite disturbance signal according to the real-time optimal signal parameters, and acquiring disturbance response data of the electrolytic cell under test according to the real-time optimal sampling parameters until the impedance test is completed; generating spectral distribution data based on the acquired disturbance response data, and calculating the impedance data of the electrolytic cell under test based on the spectral distribution data.

[0006] Furthermore, the disturbance signals of the multiple discrete frequency bands are injected synchronously through time-division multiplexing or frequency-division multiplexing.

[0007] Furthermore, the real-time status data of the electrolytic cell under test includes at least the real-time activation resistance, real-time mass transfer resistance, and real-time ohmic resistance.

[0008] Furthermore, based on the real-time state data of the electrolytic cell under test, real-time optimal sampling parameters are generated, including: determining the real-time polarization state of the electrolytic cell under test according to the real-time activation resistance, real-time mass transfer resistance and real-time ohmic resistance, wherein the real-time polarization state is an active polarization-dominated state, a conduction polarization-dominated state and a mixed state; and generating real-time optimal sampling parameters based on the real-time polarization state of the electrolytic cell under test.

[0009] Furthermore, based on the real-time polarization state of the electrolytic cell under test, real-time optimal sampling parameters are generated, including: determining a target discrete frequency band from multiple discrete frequency bands based on the real-time polarization state of the electrolytic cell under test; and determining the real-time optimal sampling frequency corresponding to the target discrete frequency band based on the real-time state data of the electrolytic cell under test. The real-time optimal signal parameters of the multi-band composite disturbance signal include the real-time optimal sampling frequency corresponding to the target discrete frequency band.

[0010] Furthermore, based on the real-time status data of the electrolytic cell under test, the real-time optimal sampling frequency corresponding to the target discrete frequency band is determined, including: when the real-time polarization state is the active polarization dominant state, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula:

[0011] ,

[0012] in, The real-time optimal sampling frequency corresponding to the target discrete frequency band. These are the characteristic frequencies of activation polarization;

[0013] When the real-time polarization state is dominated by conducted polarization, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula:

[0014] ,

[0015] in, It is the characteristic frequency of mass transfer polarization;

[0016] When the real-time polarization state is mixed, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula:

[0017] ,

[0018] in, The maximum frequency of the target discrete frequency band.

[0019] Furthermore, based on the real-time status data of the electrolytic cell under test, real-time optimal signal parameters are generated, including: generating injection duration and signal amplitude for multiple discrete frequency bands according to the real-time polarization state of the electrolytic cell under test.

[0020] Furthermore, based on the acquired impedance test data, spectral distribution data is generated, including: generating spectral distribution data based on the acquired impedance test data using compressed sensing and sparse reconstruction algorithms.

[0021] Furthermore, based on the spectral distribution data, the impedance data of the electrolytic cell under test is calculated, including:

[0022] Based on the following dynamic impedance model, calculate the impedance data of the electrolytic cell under test:

[0023] ,

[0024] in, For impedance, Let be the real-time ohmic resistance at time t. Let be the real-time activation resistance at time t. Let be the double-layer capacitance at time t. The diffusion coefficient related term at time t, is the complex frequency variable in the Laplace transform.

[0025] This invention provides a wideband injection electrolytic cell impedance testing system, applying the aforementioned wideband injection electrolytic cell impedance testing method, comprising: a disturbance injection module for generating a multi-band composite disturbance signal, wherein the multi-band composite disturbance signal includes disturbance signals of multiple discrete frequency bands; a data acquisition module for injecting the multi-band composite disturbance signal into the electrolytic cell under test, acquiring real-time status data of the electrolytic cell under test, and acquiring disturbance response data of the electrolytic cell under test according to initial sampling parameters; the data acquisition module is further configured to repeatedly execute based on the real-time status data of the electrolytic cell under test to generate real-time optimal sampling parameters, and acquire disturbance response data of the electrolytic cell under test according to the real-time optimal sampling parameters, until the impedance test is completed; and an impedance calculation module for generating spectral distribution data based on the acquired disturbance response data, and calculating the impedance data of the electrolytic cell under test according to the spectral distribution data.

[0026] Compared with existing technologies, the broadband injection electrolytic cell impedance testing system and method provided by this invention has at least the following advantages:

[0027] By injecting multi-band composite disturbance signals in a single operation, and combining this with a real-time optimal parameter dynamic adjustment mechanism, the single test cycle can be shortened, thereby improving measurement efficiency.

[0028] By employing a wide-range frequency band synchronous measurement technology, combined with an adaptive spectrum analysis algorithm, the impedance measurement error rate is reduced from ±5%-±8% in traditional methods to within ±2%.

[0029] By adjusting the optimal parameters in real time through closed-loop feedback, the signal parameters and sampling parameters are dynamically optimized during the test, reducing the system response time to the millisecond level and improving the anti-interference capability by 20dB. It is particularly suitable for online monitoring under dynamic operating conditions.

[0030] Multi-band composite signals contain multiple discrete frequency bands. Combined with iterative spectrum analysis, the impedance characteristics of the electrolytic cell under test can be obtained completely from low frequency to high frequency, avoiding the loss of characteristic information caused by frequency band switching in traditional methods. Attached Figure Description

[0031] This specification will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein:

[0032] Figure 1 This is a schematic flowchart illustrating a broadband injection electrolytic cell impedance testing method according to some embodiments of this specification;

[0033] Figure 2 This is a schematic diagram illustrating the impedance test of an electrolytic cell under test according to some embodiments of this specification;

[0034] Figure 3 This is a schematic diagram of a broadband injection electrolytic cell impedance testing system according to some embodiments of this specification. Detailed Implementation

[0035] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0036] Figure 1 This is a schematic flowchart illustrating a broadband injection electrolytic cell impedance testing method according to some embodiments of this specification, such as... Figure 1 As shown, a method for testing the impedance of a broadband injection electrolyzer may include the following steps.

[0037] Step 110: Generate a multi-band composite disturbance signal.

[0038] Among them, the multi-band composite disturbance signal includes disturbance signals in multiple discrete frequency bands.

[0039] Specifically, the frequency ranges covered by the multiple discrete frequency bands differ.

[0040] For example, multiple discrete frequency bands may include a low frequency band (0.1Hz–100Hz), a mid frequency band (100Hz–1kHz), and a high frequency band (1kHz–20kHz).

[0041] Multi-band composite disturbance signals with controllable amplitude and frequency can be generated using controllable power electronic devices. Although the electrolytic cell itself and the power supply support components will generate relatively wideband fluctuations due to switching and equipment operation, the amplitude and frequency of these wideband fluctuations are uncontrollable, and it is impossible to accurately guarantee that the entire target is measured, making them difficult to use in practice. The basic method for generating multi-band composite disturbance signals is as follows: a low-power wideband signal is amplified controllably using power electronic circuits to generate a high-power wideband signal, which is then injected into the electrolytic cell under test using a parallel voltage-type method, avoiding redundancy in full-band scanning and improving measurement efficiency.

[0042] Multiple discrete frequency band disturbance signals are injected synchronously using time-division multiplexing (TDM) or frequency-division multiplexing (FDM). TDM injects disturbance signals from different frequency bands sequentially at different time intervals. For example, low-frequency signals are injected first, followed by higher-frequency signals, with each band occupying a specific time window. This requires synchronous data acquisition for each time interval to ensure the correct frequency band is assigned. Frequency-division multiplexing, on the other hand, injects signals from multiple frequency bands simultaneously, but each band occupies a different frequency range, separated by filters. For example, the low-frequency band might use 0.1Hz-100Hz, the mid-frequency band 100Hz-1kHz, and the high-frequency band 1kHz-20kHz, transmitted simultaneously without interference.

[0043] High-frequency bands reflect double-layer charging and discharging (μs–ms level), while low-frequency bands correspond to material aging (hour level). Multi-frequency bands need to be coordinated to capture the full lifecycle characteristics. In wind power / photovoltaic hydrogen production scenarios, electrolyzers need to respond to power fluctuations within seconds. Traditional frequency sweeping methods cannot track impedance changes in real time, while multi-frequency composite perturbation signal injection can simultaneously acquire full-frequency data.

[0044] Maximum frequency requirement for electrolytic cell impedance testing ( The frequency of the measured physical process is determined by both the characteristic frequency and the requirements of the application scenario. The specific process is as follows:

[0045] Identify the polarization process (activation polarization, mass transfer polarization, ohmic loss) or aging mechanism (corrosion, blockage) to be analyzed, and calculate the characteristic frequencies of each process based on an electrochemical model (such as the Randle equivalent circuit). If the injected signal contains high-order harmonics (such as square waves or chirp signals), the highest harmonic frequency must be covered. If a square wave is injected, then the injection frequency is 10kHz.

[0046] Taking the activation and polarization process of a PEM electrolyzer as an example:

[0047] Parameter: Ract = 0.1 Ω·cm 2

[0048] Cdl=1mF / cm 2

[0049] calculate:

[0050] ,

[0051] To fully characterize the activation polarization dynamics, the maximum frequency coverage must be at least 1.59 kHz. In practice, the chosen frequency... .

[0052] Step 120: Inject the multi-band composite disturbance signal into the electrolytic cell under test, collect the real-time status data of the electrolytic cell under test, and collect the disturbance response data of the electrolytic cell under test according to the initial sampling parameters.

[0053] The real-time status data of the electrolytic cell under test includes at least the real-time activation resistance, real-time mass transfer resistance, and real-time ohmic resistance.

[0054] The initial sampling parameters may include a pre-set sampling frequency. For example, the initial sampling frequency for each discrete frequency band may be set to be greater than twice the maximum frequency of that discrete frequency band.

[0055] Figure 2 This is a schematic diagram illustrating the impedance testing of an electrolytic cell under test according to some embodiments of this specification, such as... Figure 2 As shown, the disturbance response data of the electrolytic cell under test can include current, voltage, and other data. A voltage / current transformer can be used to proportionally reduce the voltage and current of the electrolytic cell under test. The signal is further converted using a signal conditioning circuit, and finally, the data is acquired and stored using a data acquisition card and an embedded measurement and control system.

[0056] Step 130: Repeat the process based on the real-time status data of the electrolytic cell under test to generate real-time optimal sampling parameters and real-time optimal signal parameters. Adjust the multi-band composite disturbance signal according to the real-time optimal signal parameters. Collect the disturbance response data of the electrolytic cell under test according to the real-time optimal sampling parameters until the impedance test is completed.

[0057] Understandably, according to the Nyquist theorem, the sampling frequency must be greater than or equal to twice the highest frequency of the signal (i.e., However, in wideband impedance testing of electrolytic cells, if it is necessary to cover the high-frequency range (such as 20kHz), traditional methods require a sampling frequency ≥40kHz, leading to the following problems:

[0058] 1. Excessive data volume: High-frequency sampling generates massive amounts of data, resulting in high storage and processing costs;

[0059] 2. Hardware limitations: High sampling rates place stringent demands on the performance of ADC chips, leading to a significant increase in cost;

[0060] 3. Poor dynamic adaptability: A fixed sampling rate is difficult to adapt to the needs of different frequency bands (e.g., low frequencies require long-term sampling, while high frequencies require fast response).

[0061] To address this issue, this method proposes generating real-time optimal sampling parameters based on the real-time status data of the electrolytic cell under test, rather than using a fixed sampling frequency.

[0062] In some embodiments, based on the real-time state data of the electrolytic cell under test, real-time optimal sampling parameters are generated, including:

[0063] The real-time polarization state of the electrolytic cell under test is determined based on the real-time activation resistance, real-time mass transfer resistance and real-time ohmic resistance. The real-time polarization state is divided into active polarization-dominated state, conduction polarization-dominated state and mixed state.

[0064] Based on the real-time polarization state of the electrolytic cell under test, the optimal sampling parameters are generated in real time.

[0065] Specifically, when the ratio of the real-time activation resistance to the real-time ohmic resistance is greater than 3, the real-time polarization state is the active polarization-dominated state.

[0066] When the ratio of real-time mass transfer resistance to real-time activation resistance is greater than 2, the real-time polarization state is dominated by conduction polarization.

[0067] When the ratio of real-time activation resistance to real-time ohmic resistance is less than or equal to 3, or the ratio of real-time mass transfer resistance to real-time activation resistance is less than or equal to 2, the real-time polarization state is a mixed state.

[0068] In some embodiments, generating real-time optimal sampling parameters based on the real-time polarization state of the electrolytic cell under test includes:

[0069] Based on the real-time polarization state of the electrolytic cell under test, the target discrete frequency band is determined from multiple discrete frequency bands;

[0070] Based on the real-time status data of the electrolytic cell under test, the real-time optimal sampling frequency corresponding to the target discrete frequency band is determined. The real-time optimal signal parameters of the multi-band composite disturbance signal include the real-time optimal sampling frequency corresponding to the target discrete frequency band.

[0071] In some embodiments, determining the real-time optimal sampling frequency corresponding to the target discrete frequency band based on the real-time status data of the electrolytic cell under test includes:

[0072] When the real-time polarization state is the active polarization-dominated state, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula:

[0073] ,

[0074] in, The real-time optimal sampling frequency corresponding to the target discrete frequency band. These are the characteristic frequencies of activation polarization;

[0075] When the real-time polarization state is the active polarization-dominated state, the target discrete frequency band is the high-frequency band. The response of the electrolytic cell under test to interference signals in the high-frequency band is more important. By using the above formula, the real-time optimal sampling frequency of the corresponding high-frequency band can be increased, thereby quickly capturing the transient response.

[0076] When the real-time polarization state is dominated by conducted polarization, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula:

[0077] ,

[0078] in, The characteristic frequency of mass transfer polarization. The mass transfer coefficient is . The thickness of the diffusion layer;

[0079] When the real-time polarization state is dominated by conducted polarization, the target discrete frequency band is the mid-frequency band. The response of the electrolytic cell under test to interference signals in the mid-frequency band is more important. By using the above formula, the real-time optimal sampling frequency of the corresponding mid-frequency band can be increased, thereby quickly capturing the transient response.

[0080] When the real-time polarization state is mixed, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula:

[0081] ,

[0082] in, The maximum frequency of the target discrete frequency band, for example, the low frequency band is 0.1Hz - 100Hz, then It is 100Hz.

[0083] When the real-time polarization state is a mixed state, the target discrete frequency band is the low frequency band. By using the above formula, the sampling frequency corresponding to the low frequency band is reduced, the sampling time is extended to improve the low frequency resolution and reduce redundant data.

[0084] In some embodiments, generating real-time optimal signal parameters based on the real-time status data of the electrolytic cell under test includes:

[0085] Based on the real-time polarization state of the electrolytic cell under test, the injection duration and signal amplitude of multiple discrete frequency bands are generated.

[0086] Specifically, it includes the following steps:

[0087] Step 1: Determine the priority frequency band

[0088] The polarization state is determined based on real-time measurements of the activation resistance (Ract), mass transfer resistance (Rmt), and ohmic resistance (Rohm).

[0089] Activation polarization dominance: If Ract / Rohm>3, the preferred frequency band is the high frequency band (e.g., 1kHz–20kHz).

[0090] Conducted polarization dominance: If Rmt / Rac>2, the preferred frequency band is the mid-frequency band (e.g., 100Hz–1kHz).

[0091] Mixed state: Resources are evenly allocated across low-frequency, mid-frequency, and high-frequency bands.

[0092] Once priority frequency bands are determined, resources are concentrated on them. For example, the amplitude of the priority frequency band can be increased to enhance the response signal. Another example is extending the injection duration of the priority frequency band to ensure data accuracy. Using this method, data from key frequency bands is more accurate and faster, while resources are reduced for secondary frequency bands, resulting in improved overall efficiency.

[0093] Step 2: Dynamically adjust the signal amplitude

[0094] The signal amplitude must be adapted to the current impedance characteristics of the electrolytic cell to avoid overload or insufficient response. This applies to each frequency band. Amplitude The calculation is as follows:

[0095] ,

[0096] in: This is the safe voltage threshold (preset value) for the electrolytic cell. Indicates the first The total equivalent resistance of the frequency band is calculated using the three resistances Rohm, Ract, and Rmt at different frequencies. This is the amplitude adjustment factor (taken as 0.5–1.0), used to limit the maximum injected power.

[0097] Step 3: Optimize injection duration

[0098] Based on frequency band characteristics And real-time signal-to-noise ratio (SNR), dynamically adjust injection duration :

[0099] ,

[0100] in: Based on the duration coefficient (e.g.) =10 cycles); The first in the previous period Signal-to-noise ratio of the frequency band. The injection duration for the low-frequency band is extended by default to [missing value]. To ensure low-frequency resolution.

[0101] Step 4: Closed-loop feedback and parameter iteration

[0102] The spectral energy concentration of the response data in each frequency band is calculated using Fourier transform. This can be analyzed using Fourier Transform (FFT). For any discrete frequency band, if the spectral energy concentration of that band is lower than a preset spectral energy concentration threshold, the injection time or the injection amplitude needs to be increased. The preset spectral energy concentration threshold can be obtained from a large amount of experimental or historical data. By feeding back data quality, the amplitude and duration parameters in steps two and three are automatically corrected to ensure reliable measurement results. For example, amplitude adjustment: if the spectral energy concentration of the discrete frequency band is lower than the preset spectral energy concentration threshold, the amplitude is repeatedly increased to 1.2 times the current amplitude, and it is determined whether the spectral energy concentration of the discrete frequency band is lower than the preset spectral energy concentration threshold, until the spectral energy concentration of the discrete frequency band is greater than or equal to the preset spectral energy concentration threshold.

[0103] Step 140: Based on the collected disturbance response data, generate spectral distribution data, and calculate the impedance data of the electrolytic cell under test based on the spectral distribution data.

[0104] Understandably, existing Fast Fourier Transform (FFT) methods have limitations:

[0105] 1. Limited frequency resolution: resolution Depends on sampling time Increasing resolution requires extending the sampling time, making it difficult to balance speed and accuracy;

[0106] 2. Spectral leakage and picket fence effect: Non-integer period sampling leads to spectral energy dispersion, affecting the accuracy of low-frequency bands;

[0107] 3. Noise sensitivity: Wideband background noise (such as switching power supply ripple) will pollute the spectrum, especially the low signal-to-noise ratio in the high-frequency band.

[0108] Therefore, in some embodiments, spectral distribution data is generated based on the acquired disturbance response data, including: generating spectral distribution data based on the acquired impedance test data using compressed sensing and sparse reconstruction algorithms. Specifically, this involves utilizing the sparsity of the impedance spectrum in a specific transform domain (such as the wavelet domain or the ECM parameter domain) at a sub-Nyquist sampling rate. To restore the complete spectrum.

[0109] Understandably, after extracting the system's broadband response spectrum distribution data, the broadband impedance data of the system under test can be obtained using impedance calculation formulas and mathematical processing software (such as MATLAB). The static domain impedance is used: the static domain impedance is the impedance form in a static coordinate system, which can intuitively reflect the resonant point distribution of the power supply network under test. Its calculation method is as follows:

[0110] ,

[0111] in, For the static domain broadband impedance characteristics, The corresponding angular frequency; The broadband voltage response of the system under test; This represents the broadband current response of the system under test.

[0112] Limitations of impedance in the static domain:

[0113] 1. Sensitive to noise: Direct division will amplify high-frequency noise;

[0114] 2. Accumulated phase error: Errors in synchronous acquisition of voltage and current lead to deviations in phase calculation, affecting the location of the resonant point;

[0115] 3. Poor dynamic adaptability: Static impedance models are difficult to describe the time-varying characteristics of electrolyzers (such as temperature drift and aging).

[0116] Therefore, in some embodiments, the impedance data of the electrolytic cell under test is calculated based on the spectral distribution data, including:

[0117] Based on the following dynamic impedance model, calculate the impedance data of the electrolytic cell under test:

[0118] ,

[0119] in, For impedance, Let be the real-time ohmic resistance at time t. Let be the real-time activation resistance at time t. Let be the double-layer capacitance at time t. The diffusion coefficient related term at time t, is the complex frequency variable in the Laplace transform.

[0120] Figure 3 This is a schematic diagram of a broadband injection electrolytic cell impedance testing system according to some embodiments of this specification, such as... Figure 3 As shown, a broadband injection electrolytic cell impedance testing system may include a disturbance injection module, a data acquisition module, and an impedance calculation module.

[0121] The disturbance injection module is used to generate a multi-band composite disturbance signal, wherein the multi-band composite disturbance signal includes disturbance signals of multiple discrete frequency bands;

[0122] The data acquisition module is used to inject multi-band composite disturbance signals into the electrolytic cell under test, acquire real-time status data of the electrolytic cell under test, and acquire disturbance response data of the electrolytic cell under test according to the initial sampling parameters.

[0123] The data acquisition module is also used to repeatedly execute the real-time status data based on the electrolytic cell under test, generate the real-time optimal sampling parameters, and collect the disturbance response data of the electrolytic cell under test according to the real-time optimal sampling parameters until the impedance test is completed.

[0124] The impedance calculation module is used to generate spectral distribution data based on the collected disturbance response data, and to calculate the impedance data of the electrolytic cell under test based on the spectral distribution data.

[0125] A broadband injection electrolytic cell impedance testing system can be used to perform a broadband injection electrolytic cell impedance testing method, which will not be elaborated here.

[0126] Finally, it should be understood that the embodiments described in this specification are merely illustrative of the principles of the embodiments described herein. Other variations may also fall within the scope of this specification. Therefore, alternative configurations of the embodiments described herein are intended to be illustrative rather than limiting, and should be considered consistent with the teachings of this specification. Accordingly, the embodiments described herein are not limited to those explicitly introduced and described herein.

Claims

1. A method for testing the impedance of a broadband injection electrolytic cell, characterized in that, include: A multi-band composite perturbation signal is generated, wherein the multi-band composite perturbation signal includes perturbation signals of multiple discrete frequency bands; Multi-band composite disturbance signals are injected into the electrolytic cell under test, real-time status data of the electrolytic cell under test is collected, and disturbance response data of the electrolytic cell under test is collected according to the initial sampling parameters. Repeatedly execute the real-time status data based on the electrolytic cell under test, generate real-time optimal sampling parameters and real-time optimal signal parameters, adjust the multi-band composite disturbance signal according to the real-time optimal signal parameters, and collect the disturbance response data of the electrolytic cell under test according to the real-time optimal sampling parameters until the impedance test is completed; Based on the collected impedance test data, spectral distribution data is generated, and the impedance data of the electrolytic cell under test is calculated based on the spectral distribution data. The real-time status data of the electrolytic cell under test includes at least the real-time activation resistance, real-time mass transfer resistance, and real-time ohmic resistance. Based on the real-time status data of the electrolytic cell under test, real-time optimal sampling parameters are generated, including: The real-time polarization state of the electrolytic cell under test is determined based on the real-time activation resistance, real-time mass transfer resistance, and real-time ohmic resistance. The real-time polarization state is a state dominated by active polarization, a state dominated by conduction polarization, and a mixed state. Based on the real-time polarization state of the electrolytic cell under test, generate real-time optimal sampling parameters; Based on the real-time polarization state of the electrolytic cell under test, real-time optimal sampling parameters are generated, including: Based on the real-time polarization state of the electrolytic cell under test, the target discrete frequency band is determined from multiple discrete frequency bands; Based on the real-time status data of the electrolytic cell under test, the real-time optimal sampling frequency corresponding to the target discrete frequency band is determined. The real-time optimal signal parameters of the multi-band composite disturbance signal include the real-time optimal sampling frequency corresponding to the target discrete frequency band. Based on the real-time status data of the electrolytic cell under test, determine the real-time optimal sampling frequency corresponding to the target discrete frequency band, including: When the real-time polarization state is the active polarization-dominated state, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula: ， in, The real-time optimal sampling frequency corresponding to the target discrete frequency band. These are the characteristic frequencies of active polarization; When the real-time polarization state is dominated by conducted polarization, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula: ， in, It is the characteristic frequency of mass transfer polarization; When the real-time polarization state is mixed, the real-time optimal sampling frequency corresponding to the target discrete frequency band is calculated according to the following formula: ， in, The maximum frequency of the target discrete frequency band.

2. The method for testing the impedance of a broadband injection electrolytic cell according to claim 1, characterized in that, The disturbance signals of the multiple discrete frequency bands are injected synchronously through time-division multiplexing or frequency-division multiplexing.

3. The method for testing the impedance of a broadband injection electrolytic cell according to claim 1, characterized in that, Based on the real-time status data of the electrolytic cell under test, real-time optimal signal parameters are generated, including: Based on the real-time polarization state of the electrolytic cell under test, the injection duration and signal amplitude of multiple discrete frequency bands are generated.

4. The method for testing the impedance of a broadband injection electrolytic cell according to claim 1, characterized in that, Based on the acquired impedance test data, spectral distribution data is generated, including: Based on the collected impedance test data, spectral distribution data is generated using compressed sensing and sparse reconstruction algorithms.

5. The method for testing the impedance of a broadband injection electrolytic cell according to claim 1, characterized in that, Based on the spectral distribution data, the impedance data of the electrolytic cell under test is calculated, including: Based on the following dynamic impedance model, calculate the impedance data of the electrolytic cell under test: ， in, Let be the complex impedance at time t. Let be the real-time ohmic resistance at time t. Let be the real-time activation resistance at time t. Let be the double-layer capacitance at time t. The diffusion coefficient related term at time t, is the complex frequency variable in the Laplace transform.

6. A broadband injection electrolytic cell impedance testing system, characterized in that, The method for testing the impedance of a broadband injection electrolyzer according to any one of claims 1-5 includes: A disturbance injection module is used to generate a multi-band composite disturbance signal, wherein the multi-band composite disturbance signal includes disturbance signals of multiple discrete frequency bands; The data acquisition module is used to inject multi-band composite disturbance signals into the electrolytic cell under test, acquire real-time status data of the electrolytic cell under test, and acquire disturbance response data of the electrolytic cell under test according to the initial sampling parameters. The data acquisition module is also used to repeatedly execute the real-time status data based on the electrolytic cell under test, generate real-time optimal sampling parameters, and collect the disturbance response data of the electrolytic cell under test according to the real-time optimal sampling parameters until the impedance test is completed. The impedance calculation module is used to generate spectral distribution data based on the collected impedance test data, and to calculate the impedance data of the electrolytic cell under test based on the spectral distribution data.

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