Electrolytic hydrogen production system and power grid power fluctuation smoothing coordination system

Abstract

The application discloses an electrolytic hydrogen production system and power fluctuation suppression coordination system, and belongs to the technical field of electrolytic water hydrogen production and power system load regulation. The system comprises a grid-connected power identification module, an electrolytic cell state sensing module, a transition hydrogen capacity evaluation module, a candidate power trajectory generation module, a trajectory safety prediction module, a safe trajectory screening module, a dynamic safe power pipeline construction module, a trajectory execution module, a transition hydrogen purification backflow module and a compensation module for suppressing arrears. The system generates candidate power trajectories according to different regulation amplitudes, power change rates, durations and power reversal characteristics, and respectively predicts the hydrogen-oxygen side pressure difference, the gas-liquid separator liquid level, the cross-filtration risk, the temperature gradient, the single-cell voltage dispersion and the transition mass hydrogen production amount. The internal safety risks generated by rapid load increase and decrease can be identified before execution.

Description

Technical Field

[0001] This invention relates to the fields of hydrogen production by water electrolysis and power system load regulation, and more specifically, to a coordinated system for hydrogen production by water electrolysis and power grid power fluctuation mitigation. Background Technology

[0002] Electrolysis-based hydrogen production systems are characterized by adjustable load and fast response, and can serve as flexible loads for renewable energy consumption and grid power fluctuation mitigation. Patent CN113373477A discloses a method and system for controlling the electrolyte flow and pressure of a dynamic hydrogen production electrolyzer, adjusting the electrolyzer pressure and electrolyte flow based on external input power and implementing safety control based on the hydrogen content in oxygen. Patent CN111756059A discloses an electricity-hydrogen-electricity conversion system and method for real-time wind power fluctuation mitigation, utilizing hydrogen production through electrolysis, hydrogen storage, and fuel cells to achieve power conversion. Patent CN120485870A discloses a multi-electrolyzer hybrid hydrogen production control method, performing segmented balanced power distribution based on real-time power generation. The aforementioned technologies mainly focus on load tracking, pressure and flow regulation, or multi-cell power allocation. They have not yet transformed the buffering and purification capacity of transitional quality hydrogen into a real-time power regulation boundary. They also lack a continuous closed-loop mechanism for dual-layer screening of candidate power trajectories, dynamic safety power corridors, and over-limit smoothing and debt compensation. It is difficult to simultaneously take into account the grid smoothing effect, electrolyzer safety, and product hydrogen quality. Summary of the Invention

[0003] The purpose of this invention is to provide a coordinated system for electrolytic hydrogen production and grid power fluctuation mitigation, which solves the problem that existing hydrogen production load regulation methods cannot simultaneously take into account grid power fluctuation requirements, internal safety constraints of the electrolyzer, transient quality hydrogen processing capacity, and delayed compensation for unfulfilled regulation requirements.

[0004] This invention achieves the above objective through the following technical solution: a coordinated system for electrolytic hydrogen production and grid power fluctuation mitigation, the system comprising: The module includes: grid-connected power identification module, electrolyzer status sensing module, transition hydrogen capacity assessment module, candidate power trajectory generation module, trajectory safety prediction module, safety trajectory screening module, dynamic safety power corridor construction module, trajectory execution module, transition hydrogen purification and reflux module, and debt compensation module. The grid-connected power identification module is used to determine the power to be suppressed based on the actual power, target power and frequency status of the grid connection point; The electrolytic cell status sensing module is used to collect input power, cell voltage, temperature, hydrogen-oxygen side pressure, gas-liquid separator liquid level and gas purity to form the electrolytic cell operating status; The transition hydrogen capacity assessment module is used to calculate the transition hydrogen mass capacity based on the status of the transition hydrogen buffer tank, the remaining processing capacity of the purification unit, the allowable temporary storage time, and the subsequent stable hydrogen production period. The candidate power trajectory generation module is used to generate candidate power trajectories with characteristics of adjustment amplitude, power change rate, duration, and power reversal. The trajectory safety prediction module is used to predict the internal safety indicators and transition mass hydrogen production corresponding to each candidate power trajectory. The safety trajectory screening module is used to perform a two-layer screening based on internal safety constraints and transition hydrogen mass capacity. The dynamic safety power gallery construction module is used to determine the currently allowed load increase boundary, load decrease boundary, rate of change boundary, and duration boundary based on the screening results; The trajectory execution module is used to execute the target power trajectory when the power to be mitigated is located within the dynamic safe power corridor. The transition hydrogen purification and reflux module is used to buffer, purify, and reflux hydrogen that does not meet the product hydrogen output conditions. The offset compensation module is used to generate offset amount when the power to be offset exceeds the dynamic safe power of the utility tunnel, and to perform gradual compensation after the safety conditions are restored.

[0005] Furthermore, the grid-connected power identification module includes: The unit consists of an actual power acquisition unit, a target power determination unit, a frequency state discrimination unit, and a power to be mitigated calculation unit. The actual power acquisition unit is used to acquire the active power at the grid connection point; The target power determination unit is used to obtain the power grid dispatch target, grid connection plan power, or smoothing control target; The frequency state discrimination unit is used to determine whether the power grid is in a state of power surplus, power deficit, or power balance based on the frequency deviation and the direction of frequency change. The power to be balanced calculation unit is used to generate the power to be balanced under the state of power surplus, generate the power to be balanced under the state of power deficit, and output the zero adjustment command under the state of power balance.

[0006] Furthermore, the electrolytic cell status sensing module includes: Electrical parameter acquisition unit, thermal status acquisition unit, pressure status acquisition unit, liquid level acquisition unit, and gas mass acquisition unit; The electrical parameter acquisition unit is used to acquire the input power of the electrolytic cell and the voltage of each cell, and to calculate the voltage dispersion of each cell; The thermal state acquisition unit is used to acquire the inlet temperature, outlet temperature and stack temperature of the electrolytic cell, and to calculate the temperature gradient; The pressure state acquisition unit is used to acquire hydrogen-side pressure and oxygen-side pressure, and calculate the hydrogen-oxygen pressure difference. The liquid level acquisition unit is used to acquire the liquid level of the gas-liquid separator; The gas quality acquisition unit is used to collect hydrogen purity and impurity content, and output gas quality data to the trajectory safety prediction module and the transition hydrogen purification and reflux module.

[0007] Furthermore, the transition hydrogen capacity assessment module includes: The buffer tank status acquisition unit, purification capacity identification unit, temporary storage time limit determination unit, and capacity calculation unit are all included. The buffer tank status acquisition unit is used to acquire the remaining volume, internal pressure and impurity content of the transition hydrogen buffer tank; The purification capacity identification unit is used to obtain the remaining processing flow, remaining processing time, and qualified output capacity of the purification unit. The temporary storage time limit determination unit is used to determine the allowable temporary storage time based on the upper limit of the buffer tank's allowable pressure, the upper limit of the allowable impurities, and the subsequent stable hydrogen production period. The capacity calculation unit is used to convert the remaining volume, tank pressure, impurity content, remaining processing flow rate, remaining processing time, qualified output capacity, and allowable temporary storage time into transition hydrogen mass capacity.

[0008] Furthermore, the candidate power trajectory generation module includes: Amplitude discretization unit, rate of change configuration unit, duration configuration unit, and inversion feature marker unit; The amplitude discretization unit is used to generate multiple load increase or load decrease amplitudes according to the adjustment direction of the power to be smoothed. The rate of change configuration unit is used to configure the rising slope or falling slope for each load increase or load decrease amplitude; The duration configuration unit is used to configure a duration adjustment time for each candidate power trajectory; The reversal feature marking unit is used to mark the power reversal nodes in the candidate power trajectory that switch from load increase to load decrease or from load decrease to load increase, and input the power reversal nodes into the trajectory safety prediction module.

[0009] Furthermore, the trajectory safety prediction module includes: Differential pressure prediction unit, liquid level prediction unit, cross-permeability risk prediction unit, temperature gradient prediction unit, voltage dispersion prediction unit, and transition hydrogen production prediction unit; The differential pressure prediction unit is used to predict the peak differential pressure after execution based on the candidate power trajectory and the current hydrogen-oxygen side differential pressure. The liquid level prediction unit is used to predict the range of liquid level fluctuations in the gas-liquid separator. The cross-penetration risk prediction unit is used to output cross-penetration risk values ​​based on peak pressure difference, liquid level fluctuation range, gas purity, impurity content, and power change rate. The temperature gradient prediction unit is used to predict the peak value of the temperature gradient in the stack. The voltage dispersion prediction unit is used to predict the peak value of the voltage dispersion of a single cell. The transition hydrogen production prediction unit is used to output the transition mass hydrogen production based on changes in gas purity, changes in impurity content, and continuous adjustment time.

[0010] Furthermore, the safety trajectory filtering module includes: Internal security screening unit and capacity matching screening unit; The internal safety screening unit is used to compare the peak pressure difference, liquid level fluctuation range, cross-permeability risk value, temperature gradient peak value, and single-cell voltage dispersion peak value with the corresponding safety thresholds, and to eliminate any candidate power trajectory whose prediction result exceeds the corresponding safety threshold. The capacity matching and screening unit is used to compare the transition mass hydrogen production amount corresponding to the candidate power trajectory after internal safety screening with the transition hydrogen mass capacity, and to remove candidate power trajectories whose transition mass hydrogen production amount is greater than the transition hydrogen mass capacity, so as to obtain a set of safe candidate power trajectories.

[0011] Furthermore, the dynamic safety power gallery construction module includes: Trajectory set boundary extraction unit, load increase / decrease boundary determination unit, rate of change boundary determination unit, and time boundary determination unit; The trajectory set boundary extraction unit is used to extract the outer boundary of the safe candidate power trajectory set in the dimensions of adjustment direction, adjustment amplitude, power change rate, and continuous adjustment time. The load increase / decrease boundary determination unit is used to determine the maximum load increase power and the maximum load decrease power based on the outer boundary. The rate of change boundary determination unit is used to determine the maximum rate of increase in load and the maximum rate of decrease in load based on the outer boundary. The time boundary determination unit is used to determine the allowable continuous adjustment time based on the outer boundary. The dynamic safety power corridor is defined by the maximum load increase power, maximum load decrease power, maximum load increase rate of change, maximum load decrease rate of change, and allowable continuous adjustment time, and is updated according to the transition hydrogen mass capacity and the electrolyzer operating status.

[0012] Furthermore, the trajectory execution module includes: Pipe gallery matching unit, target trajectory determination unit, and power command output unit; The pipe gallery matching unit is used to determine whether the adjustment direction, adjustment amplitude, power change rate and expected duration of the power to be suppressed are within the dynamic safe power pipe gallery; The target trajectory determination unit is used to determine the target power trajectory from the set of safe candidate power trajectories when the power to be suppressed is located in the dynamic safe power corridor. The target power trajectory is consistent with the adjustment direction of the power to be suppressed and minimizes the difference in adjustment amplitude. The power command output unit is used to convert the target power trajectory into a power adjustment command for the power conversion device, so that the electrolytic cell adjusts its power consumption according to the target power trajectory.

[0013] Furthermore, the transition hydrogen purification and reflux module includes: Branch switching unit, transition buffer unit, purification treatment unit and product hydrogen reflux unit; The branch switching unit is used to determine whether the hydrogen meets the product hydrogen output conditions based on the predicted hydrogen purity or real-time hydrogen purity during the execution of the target power trajectory, and to switch to the transition hydrogen buffer branch when the product hydrogen output conditions are not met. The transition buffer unit is used to introduce the switched hydrogen into the transition hydrogen buffer tank and record the hydrogen flow rate, purity, impurity content and temporary storage time. The purification unit is used to purify the transition hydrogen according to the remaining processing capacity of the purification unit; The product hydrogen reflux unit is used to incorporate purified hydrogen into the product hydrogen output branch when the purified hydrogen meets the product hydrogen output conditions. The debt mitigation and compensation module includes a debt amount generation unit, a compensation condition judgment unit, a gradual trajectory generation unit, and a closed-loop update unit. The debt generation unit is used to control the electrolytic cell to perform the allowable adjustment part according to the boundary of the pipeline when the power to be smoothed exceeds the dynamic safe power of the pipeline, and to convert the unexecuted part into the debt smoothing amount including the adjustment direction, energy value and compensation period; The compensation condition judgment unit is used to determine whether the mass capacity of transition hydrogen has recovered to the compensation requirement capacity, and to determine whether the electrolyzer operating status meets the pressure difference safety condition, liquid level safety condition, temperature gradient safety condition, monomer voltage dispersion safety condition, and gas purity safety condition. The gradually changing trajectory generation unit is used to generate a gradually changing power trajectory when the compensation conditions are met, and to control the electrolytic cell to compensate and smooth out the backlog according to the gradually changing power trajectory. The closed-loop update unit is used to update the transition hydrogen mass capacity, electrolyzer operating status, and dynamic safety power corridor during the compensation process, and feeds back the update results to the trajectory execution module.

[0014] The beneficial effects of this invention are as follows: 1. Before issuing the power adjustment command for the electrolyzer, this invention simultaneously obtains the power to be balanced in the power grid, the operating status of the electrolyzer, and the processing capacity of the transition hydrogen, avoiding direct load increase or decrease based solely on the power grid deviation, and ensuring that the power grid adjustment requirements match the actual safety capacity of the electrolyzer.

[0015] 2. This invention generates candidate power trajectories for different adjustment amplitudes, power change rates, durations, and power reversal characteristics, and predicts the hydrogen-oxygen side pressure difference, gas-liquid separator level, cross-permeability risk, temperature gradient, individual cell voltage dispersion, and transition mass hydrogen production, which can identify internal safety risks caused by rapid load increases and decreases before execution.

[0016] 3. The present invention determines the mass capacity of transition hydrogen based on the remaining volume of the transition hydrogen buffer tank, the pressure inside the tank, the remaining processing capacity of the purification unit, the allowable temporary storage time, and the subsequent stable hydrogen production period, and uses it as the second-layer trajectory screening condition, so that the power adjustment boundary is simultaneously constrained by equipment safety and hydrogen quality processing capacity.

[0017] 4. The present invention constructs a dynamic safe power corridor by using the outer boundary of the set of safe candidate power trajectories, so that the maximum load increase power, maximum load decrease power, power change rate and continuous adjustment time are dynamically updated with the electrolyzer operating status and the mass capacity of transition hydrogen, which can improve the utilization rate of adjustable capacity compared with fixed power limits.

[0018] 5. When the power to be mitigated exceeds the dynamic safe power of the utility tunnel, this invention only executes the portion that is allowed to be adjusted within the utility tunnel, and converts the unexecuted portion into a mitigation deficit with adjustment direction, energy value and compensation period; after the safety conditions are restored, a slowly changing power trajectory compensation is adopted, thereby taking into account both immediate safety and the integrity of subsequent mitigation. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a system control flowchart of the present invention; Figure 2 This is a diagram of the electrolytic hydrogen production system and energy information interaction architecture of the present invention; Figure 3 This is a schematic diagram of the dynamic safety power gallery and candidate trajectory screening of the present invention. Detailed Implementation

[0020] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0021] Example 1: like Figure 1 and Figure 2 As shown, this embodiment provides a coordinated system for electrolytic hydrogen production and grid power fluctuation mitigation, including a grid-connected power identification module, an electrolyzer status sensing module, a transition hydrogen capacity assessment module, a candidate power trajectory generation module, a trajectory safety prediction module, a safety trajectory screening module, a dynamic safety power corridor construction module, a trajectory execution module, a transition hydrogen purification and reflux module, and a mitigation and debt compensation module. Each module is deployed on the hydrogen production station's energy management platform, station-level coordination controller, or edge control terminal, and is communicatively connected to the grid-connected metering device, power conversion device, electrolyzer stack, gas-liquid separator, transition hydrogen buffer tank, purification unit, and product hydrogen output branch.

[0022] In this embodiment, the system's data sampling period is uniformly set to 1. Power is uniformly adopted As a unit of measurement, the rate of change of power is uniformly adopted. As a unit of measurement, time is uniformly adopted. As a unit of measurement, pressure is uniformly adopted. As a unit of measurement, temperature is uniformly adopted. As a unit of measurement, voltage is uniformly used, and hydrogen quantity is uniformly converted to standard conditions. Hydrogen flow rate is uniformly adopted As units of measurement, the liquid level in the gas-liquid separator is expressed as a percentage, while the hydrogen purity and impurity content are expressed as a volume fraction percentage.

[0023] The grid-connected power identification module acquires the actual power, target power, and grid frequency status at the grid connection point. The target power is determined by the grid dispatch target, grid-connected planned power, or power smoothing control target. The frequency status discrimination unit determines whether the grid is in a power surplus state, a power deficit state, or a power balance state based on the frequency deviation and the direction of frequency change. The power to be smoothed is determined according to formula (1):

[0024] In the formula, for The power to be smoothed at any given time, in units of ; for Actual power at the grid connection point at any given time, in units of ; for Target power at time, in units of .when When >0, the system generates an overload-type power to be mitigated; when When <0, the system generates a load-reducing power to be mitigated; when | |≤ At this time, the system does not trigger the electrolytic cell power adjustment.

[0025] Power dead zone threshold Take 0.5 times the rated range of the power metering device at the grid connection point. Up to 1.0 The smaller of the allowable deviations from grid dispatch. In this embodiment, the rated range of the power metering device at the grid connection point is 10000. The allowable deviation for power grid dispatch is 50. ,therefore Take 50 This is to avoid frequent load increases and decreases in the electrolytic cell caused by small power fluctuations.

[0026] The electrolyzer status sensing module collects data on the electrolyzer input power, individual cell voltages, inlet and outlet temperatures, temperatures at key locations within the stack, hydrogen-side pressure, oxygen-side pressure, gas-liquid separator level, hydrogen purity, and impurity content. Individual cell voltage dispersion is characterized by the standard deviation of each cell voltage relative to the average individual cell voltage; temperature gradient is characterized by the difference between the highest and lowest temperatures in the stack; hydrogen-oxygen side pressure difference is characterized by the absolute value of the difference between hydrogen-side and oxygen-side pressures; and liquid level fluctuation range is characterized by the absolute value of the difference between the real-time liquid level and the target liquid level.

[0027] Each internal safety threshold is determined jointly based on the equipment manufacturer's technical documents, trial operation data, and on-site safety procedures. When values ​​given by different bases are inconsistent, the more stringent value is adopted. Hydrogen-oxygen side pressure difference threshold. Take 80% of the manufacturer's allowed maximum. And not higher than 0.080 Gas-liquid separator liquid level fluctuation threshold Take 50% of the normal operating liquid level range width and not higher than 15 Temperature gradient threshold Take 80% of the manufacturer's maximum allowable temperature difference. and not higher than 10 Individual voltage dispersion threshold Take twice the mean dispersion over 30 consecutive stable operating cycles, but not exceeding 0.030. Cross-penetration risk threshold Take 0.70; Product hydrogen purity threshold Based on the highest purity requirements stipulated in the hydrogen supply agreement, on-site quality control requirements, and downstream equipment requirements, this embodiment uses 99.90%. .

[0028] The transition hydrogen capacity assessment module obtains the effective geometric volume, current pressure, allowable pressure limit, and impurity content of the transition hydrogen buffer tank, and obtains the remaining processing flow rate, remaining processing time, allowable temporary storage time, and subsequent stable hydrogen production period of the purification unit. The transition hydrogen mass capacity is determined according to formula (2):

[0029] In the formula, Transition hydrogen mass capacity, in units of ; For purification and recovery efficiency, dimensionless; The amount of hydrogen that the transition hydrogen buffer tank can receive, calculated according to standard conditions, is expressed in units of... Its effective geometric volume is determined by the transition hydrogen buffer tank. Permissible pressure limit Current pressure and standard pressure Sure; The amount of hydrogen that the purification unit can process during the permitted temporary storage period is expressed in units of... It is determined by the remaining processing flow of the purification unit. and allowed storage time Sure; This represents the amount of hydrogen that can be purified and processed during the subsequent stable hydrogen production period, in units of... , its origin and subsequent stable hydrogen production period Sure.

[0030] according to Divide by the product of pressure margin Conversion; according to and The product is determined; according to and The product is determined by formula (2). The minimum value of the three capacities is multiplied by the purification and recovery efficiency to avoid any constraint of buffer tank capacity, purification capacity or subsequent processing time exceeding the limit. The ratio of the amount of qualified hydrogen purified by the purification unit in the past 30 days to the total amount of transition hydrogen entering the purification unit is used; if the operating record is less than 30 days, 90% of the manufacturer's rated recovery efficiency is used. . The minimum value among the following is determined based on the time required for the buffer tank pressure to reach the upper limit, the time required for the impurity content to reach the upper limit, and the maximum temporary storage time specified within the station.

[0031] The candidate power trajectory generation module generates multiple candidate power trajectories based on the power to be mitigated. Each candidate power trajectory includes the adjustment direction, adjustment amplitude, power change rate, duration of adjustment, and power reversal characteristics. The discrete interval of the adjustment amplitude is taken from the rated power of the electrolytic cell. 5 Up to 10 The discrete interval for the power change rate is taken as 20% of the rated ramping capacity of the power conversion device. Up to 30 ; The continuous adjustment time is based on 5 10 and 15 Hierarchical settings. When the power grid status changes from power surplus to power deficit, or from power deficit to power surplus, within two consecutive sampling periods, the corresponding candidate power trajectory is marked as having power reversal characteristics.

[0032] The trajectory safety prediction module predicts the peak value of the hydrogen-oxygen side pressure difference, the range of liquid level fluctuation in the gas-liquid separator, the risk value of cross-permeability, the peak value of the temperature gradient, the peak value of the monomer voltage dispersion, and the amount of hydrogen produced in the transition mass based on the candidate power trajectory and the current operating status of the electrolyzer. To avoid the unclear source of weights due to the weighted summation of multiple safety indicators, this embodiment uses a normalized threshold comparison method to determine the internal safety status of the candidate power trajectory, as shown in formula (3):

[0033] In the formula, For the first The internal safety normalization index of the candidate power trajectory is dimensionless. It is the ratio of the peak value of the hydrogen-oxygen side pressure difference to the threshold value of the hydrogen-oxygen side pressure difference; This is the ratio of the liquid level fluctuation range to the liquid level fluctuation threshold in the gas-liquid separator. This is the ratio of the cross-penetration risk value to the cross-penetration risk threshold. This is the ratio of the peak temperature gradient to the temperature gradient threshold. This is the ratio of the peak value of the individual voltage dispersion to the threshold value of the individual voltage dispersion. All the above normalized quantities are dimensionless. When... When ≤1, the candidate power trajectory passes the internal safety screening; when When the value is greater than 1, the corresponding candidate power trajectory is removed.

[0034] The safety trajectory filtering module performs a two-layer filtering of candidate power trajectories. The first layer is an internal safety filtering, which eliminates... Candidate power trajectories with a value >1; the second layer is capacity matching screening, which determines the transition mass hydrogen production corresponding to the candidate power trajectories that pass the first layer screening. With transition hydrogen mass capacity In comparison, when ≤ When the corresponding candidate power trajectory is retained, > The corresponding candidate power trajectory is removed at that time. By testing hydrogen with a purity lower than The hydrogen flow rate during this period is obtained by integrating over time, with units of... .

[0035] The dynamic safe power gallery construction module extracts the outer boundaries of the adjustment amplitude, power change rate, and continuous adjustment time from the set of safe candidate power trajectories, and determines the maximum load increase power accordingly. Maximum load reduction power Maximum load change rate Maximum unload change rate and allowable continuous adjustment time The aforementioned boundaries are determined by the current set of safe candidate power trajectories, not by fixed empirical values. This occurs when the transition hydrogen mass capacity decreases and the hydrogen-oxygen side pressure difference approaches... The liquid level is close to the allowable limit or the hydrogen purity is close to... At that time, the set of safe candidate power trajectories shrinks, and the dynamic safe power corridor narrows synchronously.

[0036] The trajectory execution module determines whether the adjustment direction, adjustment amplitude, power change rate, and expected duration of the power to be mitigated are within the dynamic safe power corridor. If they are within the corridor, the module selects the candidate power trajectory from the set of safe candidate power trajectories that has the same adjustment direction as the power to be mitigated and the smallest difference in adjustment amplitude as the target power trajectory, and converts it into a power adjustment command for the power conversion device.

[0037] During the execution of the target power trajectory, the transition hydrogen purification reflux module continuously acquires the predicted hydrogen purity and the real-time hydrogen purity. When the hydrogen purity is lower than... At that time, the corresponding hydrogen is switched from the product hydrogen output branch to the transition hydrogen buffer branch, and the hydrogen flow rate, purity, impurity content, and temporary storage time are recorded. Purification is then carried out according to the remaining processing capacity of the purification unit; when the purity of the purified hydrogen is not lower than At that time, the purified qualified hydrogen will be reintegrated into the product hydrogen output branch.

[0038] When the power to be mitigated exceeds the dynamic safe power of the utility tunnel, the trajectory execution module performs the allowable adjustment according to the boundary of the utility tunnel. The mitigation deficit compensation module converts the difference between the mitigation power required by the power grid and the mitigation power actually performed by the electrolyzer into the mitigation deficit amount. The energy value corresponding to the mitigation deficit amount is determined according to formula (4):

[0039] In the formula, The energy value corresponding to the amount of outstanding debt is expressed in units of [missing information]. ; The power level required by the power grid, in units of ; The actual power reduction achieved by the electrolyzer, in units of ; and These represent the start and end times of the overlimit smoothing, respectively. The integration time is uniformly converted to [value missing] during calculation. The measures to mitigate the shortfall also include adjustment direction and compensation period, with the compensation period taking priority from the period given by the power grid dispatch; if no period is given, it shall not exceed three times the subsequent stable hydrogen production period.

[0040] The compensation condition judgment unit determines whether the transition hydrogen mass capacity has recovered to the compensation requirement capacity, and whether the hydrogen-oxygen side pressure difference, gas-liquid separator level, temperature gradient, monomer voltage dispersion, and hydrogen purity meet the corresponding safety conditions. When the compensation conditions are met, a slowly varying power trajectory is generated. The power change rate of the slowly varying power trajectory is taken as 30% of the power change rate of the original target power trajectory. Up to 50 And it does not exceed the current dynamic safety power corridor's rate of change boundary. During the compensation process, it follows 1 The sampling cycle updates the electrolyzer operating status, transition hydrogen mass capacity, and dynamic safety power corridor; compensation is suspended when any safety indicator reaches the corresponding threshold, and resumes execution after the safety conditions are restored.

[0041] In one specific embodiment, the rated power of the electrolytic cell For 1000 The current operating power is 600. The permissible power range is 200. Up to 1000 The rated ramping capability of the power conversion device is 80. Target power at grid connection point ( ) is 5000 Actual power ( ) is 5300 The power to be mitigated is obtained according to formula (1). ( ) is 300 The system triggers load-increased power easing control.

[0042] The pressure difference between the hydrogen and oxygen sides was measured to be 0.020 at that moment. The target liquid level for the gas-liquid separator is 50. The current liquid level is 52. The highest temperature in the reactor body is 64°C. The lowest temperature is 58. The voltage dispersion of a single unit is 0.012. The hydrogen purity is 99.96%. Based on the equipment manufacturer's technical documents, trial operation data, and on-site safety procedures, the following determinations were made. It is 0.080 , 15 , It is 0.70. 10 , It is 0.030 , 99.90 .

[0043] Effective geometric volume of transition hydrogen buffer tank 30 Allowable pressure limit 1.60 Current pressure 1.10 The remaining processing flow rate of the purification unit is 6. Allowed storage time 15 Subsequent stable hydrogen production period For 20 Purification and recycling efficiency The value is 0.95. According to formula (2), the acceptable hydrogen volume calculated from the buffer tank pressure margin is approximately 148.0, and the hydrogen volume that can be processed during the allowable temporary storage period is 90. The amount of hydrogen that can be processed during the subsequent stable hydrogen production period is 120. The transition hydrogen mass capacity was obtained. It is 85.5 .

[0044] The candidate power trajectory generation module revolves around 300 The load demand generates candidate power trajectories, and the adjustment amplitude is set to 100. 150 200 250 and 300 The power change rate is set to 20. 40 and 60 The duration of adjustment is set to 5. 10 and 15 Adjust the amplitude to 300. Power change rate 60 Continuous adjustment time 10 Taking the candidate power trajectory as an example, the predicted peak value of the hydrogen-oxygen side pressure difference is 0.070. The liquid level fluctuation range is 13. The cross-penetration risk value is 0.62, and the peak temperature gradient is 8. The peak value of the individual voltage dispersion is 0.026. , 18 Corresponding The values ​​are 0.875, 0.867, 0.886, 0.800, and 0.867 respectively, obtained according to formula (3). It is 0.886. Because... ≤1 and ≤ The candidate power trajectory was selected through a two-layer screening process.

[0045] Based on the outer boundary of the set of safe candidate power trajectories, determine For 300 , 250 , For 60 , 40 , 10 The current power to be mitigated is located within the dynamic safety power corridor, and the trajectory execution module controls the electrolytic cell from 600... Increased to 900 During execution, if the hydrogen purity is lower than 99.90%, Then the corresponding hydrogen will be switched to the transition hydrogen buffer tank, and according to 6 The remaining processing flow is purified, and after passing the purification, it is returned to the product hydrogen branch.

[0046] In another operating scenario, the actual power at the grid connection point was 5360. The target power remains at 5000. The power to be mitigated is 360. .because For 300 The system executed 300 Load, and remove the 60 unexecuted Convert to mitigating outstanding debts. If the over-limit status continues for 10... Calculated according to formula (4) 10 When the transition hydrogen mass capacity recovers and all internal safety indicators meet the threshold conditions, the system adopts a 20 The gradually varying power trajectory compensates for the amount of debt owed.

[0047] Through the above implementation methods, the present invention incorporates the power grid to be smoothed, the internal safety status of the electrolyzer, the quality and capacity of transition hydrogen, the dynamic safety power corridor, and the over-limit smoothing deficit into the same closed-loop control process. Before power regulation, candidate trajectory prediction and double-layer screening are completed. During the power regulation process, transition hydrogen buffer purification and reflux are completed. When the regulation capacity is insufficient, deficit recording and delayed compensation are completed, thereby achieving the synergy of power grid power fluctuation smoothing, safe operation of the electrolyzer, and product hydrogen quality control.

[0048] The above embodiments provide a detailed description of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A coordinated system for electrolytic hydrogen production and grid power fluctuation mitigation, characterized in that, The system includes: The module includes: grid-connected power identification module, electrolyzer status sensing module, transition hydrogen capacity assessment module, candidate power trajectory generation module, trajectory safety prediction module, safety trajectory screening module, dynamic safety power corridor construction module, trajectory execution module, transition hydrogen purification and reflux module, and debt compensation module. The grid-connected power identification module is used to determine the power to be suppressed based on the actual power, target power and frequency status of the grid connection point; The electrolytic cell status sensing module is used to collect input power, cell voltage, temperature, hydrogen-oxygen side pressure, gas-liquid separator liquid level and gas purity to form the electrolytic cell operating status; The transition hydrogen capacity assessment module is used to calculate the transition hydrogen mass capacity based on the status of the transition hydrogen buffer tank, the remaining processing capacity of the purification unit, the allowable temporary storage time, and the subsequent stable hydrogen production period. The candidate power trajectory generation module is used to generate candidate power trajectories with characteristics of adjustment amplitude, power change rate, duration, and power reversal. The trajectory safety prediction module is used to predict the internal safety indicators and transition mass hydrogen production corresponding to each candidate power trajectory. The safety trajectory screening module is used to perform a two-layer screening based on internal safety constraints and transition hydrogen mass capacity. The dynamic safety power gallery construction module is used to determine the currently allowed load increase boundary, load decrease boundary, rate of change boundary, and duration boundary based on the screening results; The trajectory execution module is used to execute the target power trajectory when the power to be mitigated is located within the dynamic safe power corridor. The transition hydrogen purification and reflux module is used to buffer, purify, and reflux hydrogen that does not meet the product hydrogen output conditions. The offset compensation module is used to generate offset amount when the power to be offset exceeds the dynamic safe power of the utility tunnel, and to perform gradual compensation after the safety conditions are restored.

2. The electrolytic hydrogen production system and grid power fluctuation mitigation coordinated system according to claim 1, characterized in that, The grid-connected power identification module includes: The unit consists of an actual power acquisition unit, a target power determination unit, a frequency state discrimination unit, and a power to be mitigated calculation unit. The actual power acquisition unit is used to acquire the active power at the grid connection point; The target power determination unit is used to obtain the power grid dispatch target, grid connection plan power, or smoothing control target; The frequency state discrimination unit is used to determine whether the power grid is in a state of power surplus, power deficit, or power balance based on the frequency deviation and the direction of frequency change. The power to be balanced calculation unit is used to generate the power to be balanced under the state of power surplus, generate the power to be balanced under the state of power deficit, and output the zero adjustment command under the state of power balance.

3. The electrolytic hydrogen production system and grid power fluctuation mitigation coordinated system according to claim 1, characterized in that, The electrolytic cell status sensing module includes: Electrical parameter acquisition unit, thermal status acquisition unit, pressure status acquisition unit, liquid level acquisition unit, and gas mass acquisition unit; The electrical parameter acquisition unit is used to acquire the input power of the electrolytic cell and the voltage of each cell, and to calculate the voltage dispersion of each cell; The thermal state acquisition unit is used to acquire the inlet temperature, outlet temperature and stack temperature of the electrolytic cell, and to calculate the temperature gradient; The pressure state acquisition unit is used to acquire hydrogen-side pressure and oxygen-side pressure, and calculate the hydrogen-oxygen pressure difference. The liquid level acquisition unit is used to acquire the liquid level of the gas-liquid separator; The gas quality acquisition unit is used to collect hydrogen purity and impurity content, and output gas quality data to the trajectory safety prediction module and the transition hydrogen purification and reflux module.

4. The electrolytic hydrogen production system and the grid power fluctuation mitigation coordinated system according to claim 1, characterized in that, The transition hydrogen capacity assessment module includes: The buffer tank status acquisition unit, purification capacity identification unit, temporary storage time limit determination unit, and capacity calculation unit are all included. The buffer tank status acquisition unit is used to acquire the remaining volume, internal pressure and impurity content of the transition hydrogen buffer tank; The purification capacity identification unit is used to obtain the remaining processing flow, remaining processing time, and qualified output capacity of the purification unit. The temporary storage time limit determination unit is used to determine the allowable temporary storage time based on the upper limit of the buffer tank's allowable pressure, the upper limit of the allowable impurities, and the subsequent stable hydrogen production period. The capacity calculation unit is used to convert the remaining volume, tank pressure, impurity content, remaining processing flow rate, remaining processing time, qualified output capacity, and allowable temporary storage time into transition hydrogen mass capacity.

5. The electrolytic hydrogen production system and the grid power fluctuation mitigation coordinated system according to claim 1, characterized in that, The candidate power trajectory generation module includes: Amplitude discretization unit, rate of change configuration unit, duration configuration unit, and inversion feature marker unit; The amplitude discretization unit is used to generate multiple load increase or load decrease amplitudes according to the adjustment direction of the power to be smoothed. The rate of change configuration unit is used to configure the rising slope or falling slope for each load increase or load decrease amplitude; The duration configuration unit is used to configure a duration adjustment time for each candidate power trajectory; The reversal feature marking unit is used to mark the power reversal nodes in the candidate power trajectory that switch from load increase to load decrease or from load decrease to load increase, and input the power reversal nodes into the trajectory safety prediction module.

6. The electrolytic hydrogen production system and the grid power fluctuation mitigation coordinated system according to claim 5, characterized in that, The trajectory safety prediction module includes: Differential pressure prediction unit, liquid level prediction unit, cross-permeability risk prediction unit, temperature gradient prediction unit, voltage dispersion prediction unit, and transition hydrogen production prediction unit; The differential pressure prediction unit is used to predict the peak differential pressure after execution based on the candidate power trajectory and the current hydrogen-oxygen side differential pressure. The liquid level prediction unit is used to predict the range of liquid level fluctuations in the gas-liquid separator. The cross-penetration risk prediction unit is used to output cross-penetration risk values ​​based on peak pressure difference, liquid level fluctuation range, gas purity, impurity content, and power change rate. The temperature gradient prediction unit is used to predict the peak value of the temperature gradient in the stack. The voltage dispersion prediction unit is used to predict the peak value of the voltage dispersion of a single cell. The transition hydrogen production prediction unit is used to output the transition mass hydrogen production based on changes in gas purity, changes in impurity content, and continuous adjustment time.

7. The electrolysis hydrogen production system and grid power fluctuation mitigation coordinated system according to claim 6, characterized in that, The safety trajectory filtering module includes: Internal security screening unit and capacity matching screening unit; The internal safety screening unit is used to compare the peak pressure difference, liquid level fluctuation range, cross-permeability risk value, temperature gradient peak value, and single-cell voltage dispersion peak value with the corresponding safety thresholds, and to eliminate any candidate power trajectory whose prediction result exceeds the corresponding safety threshold. The capacity matching and screening unit is used to compare the transition mass hydrogen production amount corresponding to the candidate power trajectory after internal safety screening with the transition hydrogen mass capacity, and to remove candidate power trajectories whose transition mass hydrogen production amount is greater than the transition hydrogen mass capacity, so as to obtain a set of safe candidate power trajectories.

8. The electrolytic hydrogen production system and the grid power fluctuation mitigation coordinated system according to claim 7, characterized in that, The dynamic safe power corridor construction module includes: Trajectory set boundary extraction unit, load increase / decrease boundary determination unit, rate of change boundary determination unit, and time boundary determination unit; The trajectory set boundary extraction unit is used to extract the outer boundary of the safe candidate power trajectory set in the dimensions of adjustment direction, adjustment amplitude, power change rate, and continuous adjustment time. The load increase / decrease boundary determination unit is used to determine the maximum load increase power and the maximum load decrease power based on the outer boundary. The rate of change boundary determination unit is used to determine the maximum rate of increase in load and the maximum rate of decrease in load based on the outer boundary. The time boundary determination unit is used to determine the allowable continuous adjustment time based on the outer boundary. The dynamic safety power corridor is defined by the maximum load increase power, maximum load decrease power, maximum load increase rate of change, maximum load decrease rate of change, and allowable continuous adjustment time, and is updated according to the transition hydrogen mass capacity and the electrolyzer operating status.

9. The electrolytic hydrogen production system and the grid power fluctuation mitigation coordinated system according to claim 8, characterized in that, The trajectory execution module includes: Pipe gallery matching unit, target trajectory determination unit, and power command output unit; The pipe gallery matching unit is used to determine whether the adjustment direction, adjustment amplitude, power change rate and expected duration of the power to be suppressed are within the dynamic safe power pipe gallery; The target trajectory determination unit is used to determine the target power trajectory from the set of safe candidate power trajectories when the power to be suppressed is located in the dynamic safe power corridor. The target power trajectory is consistent with the adjustment direction of the power to be suppressed and minimizes the difference in adjustment amplitude. The power command output unit is used to convert the target power trajectory into a power adjustment command for the power conversion device, so that the electrolytic cell adjusts its power consumption according to the target power trajectory.

10. The electrolytic hydrogen production system and the grid power fluctuation mitigation coordinated system according to claim 9, characterized in that, The transition hydrogen purification and reflux module includes: Branch switching unit, transition buffer unit, purification treatment unit and product hydrogen reflux unit; The branch switching unit is used to determine whether the hydrogen meets the product hydrogen output conditions based on the predicted hydrogen purity or real-time hydrogen purity during the execution of the target power trajectory, and to switch to the transition hydrogen buffer branch when the product hydrogen output conditions are not met. The transition buffer unit is used to introduce the switched hydrogen into the transition hydrogen buffer tank and record the hydrogen flow rate, purity, impurity content and temporary storage time. The purification unit is used to purify the transition hydrogen according to the remaining processing capacity of the purification unit; The product hydrogen reflux unit is used to incorporate purified hydrogen into the product hydrogen output branch when the purified hydrogen meets the product hydrogen output conditions. The debt mitigation and compensation module includes a debt amount generation unit, a compensation condition judgment unit, a gradual trajectory generation unit, and a closed-loop update unit. The debt generation unit is used to control the electrolytic cell to perform the allowable adjustment part according to the boundary of the pipeline when the power to be smoothed exceeds the dynamic safe power of the pipeline, and to convert the unexecuted part into the debt smoothing amount including the adjustment direction, energy value and compensation period; The compensation condition judgment unit is used to determine whether the mass capacity of transition hydrogen has recovered to the compensation requirement capacity, and to determine whether the electrolyzer operating status meets the pressure difference safety condition, liquid level safety condition, temperature gradient safety condition, monomer voltage dispersion safety condition, and gas purity safety condition. The gradually changing trajectory generation unit is used to generate a gradually changing power trajectory when the compensation conditions are met, and to control the electrolytic cell to compensate and smooth out the backlog according to the gradually changing power trajectory. The closed-loop update unit is used to update the transition hydrogen mass capacity, electrolyzer operating status, and dynamic safety power corridor during the compensation process, and feeds back the update results to the trajectory execution module.

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