Method and system for regulating and controlling proportion of synthesis gas of SOEC electric pile

Abstract

The invention discloses a method and a system for regulating and controlling the proportion of synthesis gas of an SOEC electric pile. The method comprises the following steps: setting and initializing a target; the method comprises the following steps: acquiring an H2 / CO actual proportion Ractual and multi-source operation parameters of a stack outlet in real time, calculating a proportion deviation delta R = Ractual-Rtarget, and executing hierarchical regulation and control; all regulation and control actions need to follow a preset heat-electricity-gas coupling safety boundary. According to the technical scheme, through an in-situ feedback-multi-parameter cooperative control mechanism, strong coupling limitation of temperature, current density and gas phase flow velocity is broken through, precise regulation and control of the H2 / CO proportion of the synthesis gas are achieved, and the strict proportion requirements of processes such as methanol synthesis and Fischer-Tropsch synthesis on raw material gas are met. According to the synthesis gas proportion regulation and control system of the SOEC electric pile, safety interlocking and trend pre-judgment can be carried out, and compared with traditional manual intervention, the fault recovery time is shorter.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of energy storage and energy utilization, in particular to a syngas proportion regulation method and system of SOEC stack. BACKGROUND

[0002] The solid oxide electrolysis cell (SOEC) high-temperature co-electrolysis technology directly generates syngas by synchronously electrolyzing CO2 and H2O, and has the following advantages: the theoretical conversion efficiency is much higher than that of low-temperature electrolysis, non-noble metal catalysts are used, and the high-temperature operation characteristics of 700-900°C are naturally adapted to the temperature level and energy flow of industrial waste heat, so that the raw material preheating and system thermal management can be strengthened through waste heat, the dependence on external high-temperature heat source is greatly reduced, and the overall energy utilization efficiency is significantly improved. Therefore, the SOEC technology is an optimal platform for the deep integration of renewable power consumption, CO2 conversion and industrial waste heat recovery.

[0003] However, the large-scale application of this technology still faces key challenges: in addition to the continuous improvement of long-term stability of the electrode (such as high-temperature attenuation and carbon deposition), the core constraint is the lack of precise syngas H2 / CO ratio regulation capability. The existing methods mainly rely on preset H2O / CO2 inlet ratio to adjust the final product, but the actual output ratio is disturbed by nonlinear coupling of parameters such as temperature, current density, gas flow rate, and catalyst activity, resulting in low regulation accuracy and response lag; and there is a lack of real-time gas component feedback and multi-parameter collaborative control mechanism, making it difficult to dynamically adapt to downstream demand, and the lack of integration and intelligence also restricts the operation economy.

[0004] The existing related technologies have obvious limitations: the system disclosed in Chinese patent CN111549355A couples a CO2 adsorption unit with a SOEC unit, which can generate syngas, but the product ratio is fixed (H2 / CO ≈ 1:1 or 2:1), lacks dynamic regulation capability, and relies on methane to assist in reducing overpotential, increasing the complexity of the system and carbon source consumption. Chinese patent CN119095792A mainly performs static and extensive regulation through CO2 bypass, which has poor adaptability to renewable energy input fluctuations, and lacks multi-parameter collaborative mechanism and real-time feedback. Chinese patent CN119876970A only regulates by setting the initial H2 proportion, which is single-dimensional, and does not form a dynamic closed-loop control of current, temperature and other key parameters and syngas ratio, and cannot actively adapt to downstream demand.

[0005] Therefore, developing an integrated SOEC co-electrolysis system, overcoming the bottleneck of real-time and accurate syngas ratio regulation, and building a multi-variable collaborative control strategy based on online feedback have great application value for realizing renewable energy-driven "on-demand gas generation" and breaking through the technical barriers of CO2 high-value utilization. Not only can it improve the competitiveness of SOEC technology, but also provide core support for building a zero-carbon fuel and chemical supply chain. SUMMARY

[0006] In order to solve the above technical problems, the application discloses a syngas proportion regulation method and system for an SOEC stack, which adopts in-situ gas feedback and multi-parameter collaborative control technology to realize accurate regulation of the H2 / CO ratio and meet the strict requirements of different downstream processes on the composition of syngas.

[0007] To this end, the application adopts the technical scheme of:

[0008] The syngas proportion regulation method for the SOEC stack comprises the following steps:

[0009] Step S1, target setting and initialization: according to the requirements of the downstream process, a target H2 / CO ratio value R_target is set, and working parameters are initialized to a preset working condition;

[0010] Step S2, real-time acquisition of the actual H2 / CO ratio R_actual at the outlet of the stack and multi-source operating parameters, wherein the multi-source operating parameters include temperature field distribution, current density, impedance spectrum, gas flow rate and system pressure;

[0011] Step S3, calculation of the proportion deviation ΔR = |R_actual-R_target|, and execution of the following hierarchical regulation:

[0012] When ΔR≤3%, the H2O / CO2 ratio of the inlet gas is adjusted, and the single adjustment step is ≤5vol%;

[0013] When 3%<ΔR≤10%, the current density and the temperature field are collaboratively adjusted based on an electrochemical reaction kinetics model, wherein the current density is adjusted by 0.05A / cm 2 Step length increase and decrease, the temperature field is compensated within a range of ±20℃, and the axial temperature difference of the stack is maintained to be ≤0.8℃;

[0014] When ΔR>10%, a neural network trend prediction model is activated, the H2 / CO ratio change trend is analyzed and predicted according to the multi-source operating parameters, and the combined parameters of the H2O / CO2 inlet gas ratio, the current density, the gas flow rate and the working temperature are dynamically optimized and adjusted;

[0015] All regulation actions need to follow preset thermal-electric-gas coupling safety boundaries, including: a temperature gradient ≤5K / cm, a fuel utilization rate ∈[70%, 90%], a current density ≤1A / cm 2 , a temperature change rate ≤4K / min; if the regulation instruction violates the constraint condition of any thermal-electric-gas coupling safety boundary, the safety constraint that is met is preferentially executed, and a higher-level regulation or a safety response is triggered.

[0016] As a further improvement of the application, the syngas proportion regulation method of the SOEC stack is characterized in that when CH4 concentration > 50ppm or ΔR lasts > 15%, a four-level interlock protection is triggered, and current cut-off, inert gas flushing, feed cut to protective gas and uploading fault code are sequentially executed.

[0017] As a further improvement of the application, in step S2, the H2 / CO actual proportion R_actual at the stack outlet and the sampling frequency of the multi-source operating parameter are collected in real time, the sampling frequency is ≥ 0.5H2, and the detection accuracy is ± 1%.

[0018] As a further improvement of the application, in step S3, the neural network trend prediction model performs the following operations:

[0019] Based on the current R_actual, historical data and multi-source operating parameters, the H2 / CO proportion change trend in the future short period is predicted;

[0020] The optimal adjustment parameter combination of the gas inlet proportion, current density, gas flow rate and working temperature is dynamically generated with the optimization target of minimizing ΔR;

[0021] The multi-source operating parameters include the current R_actual, historical data, temperature, current, flow rate and pressure.

[0022] As a further improvement of the application, in step S3, the synergistic adjustment of the current density and the temperature field is executed synchronously with the current density adjustment and the temperature compensation, and the temperature compensation amount is dynamically calculated according to the electrochemical reaction kinetics model; the internal temperature field distribution of the stack is collected by an embedded thermocouple array.

[0023] As a further improvement of the application, the initialization parameters include: working temperature 800℃, fuel utilization rate 85%, and air input amount 2 times the fuel electrode flow rate.

[0024] The application discloses a syngas proportion regulation system of a SOEC stack, which comprises:

[0025] A target setting and initialization unit is used for setting a target H2 / CO proportion value R_target according to the downstream process demand, and initializing working parameters to a preset working condition.

[0026] The in-situ gas component detection data and parameter acquisition unit is used for acquiring the H2 / CO actual proportion R_actual at the stack outlet and multi-source operating parameters in real time.

[0027] a data processing and regulation execution unit for calculating the proportional deviation ΔR = |R_actual - R_target| and performing the following hierarchical regulation: when ΔR ≤ 3%, the H2O / CO2 ratio of the intake gas is adjusted, and the single adjustment step is ≤ 5vol%;

[0028] when 3% < ΔR ≤ 10%, the current density and the temperature field are adjusted based on the electrochemical reaction kinetics model, the current density is adjusted by 0.05A / cm 2 step, the temperature field is compensated within a range of ±20℃, and the axial temperature difference of the stack is maintained to be ≤ 0.8℃;

[0029] when ΔR > 10%, a neural network trend prediction model is activated to predict the H2 / CO ratio change trend according to multi-source operating parameters, and the combined parameters of the H2O / CO2 intake ratio, the current density, the gas flow rate and the working temperature are dynamically optimized;

[0030] and all the regulation actions need to follow the preset thermal-electric-gas coupling safety boundary, including: a temperature gradient ≤ 5K / cm, a fuel utilization ∈ [70%, 90%], a current density ≤ 1A / cm 2 , and a temperature change rate ≤ 4K / min.

[0031] As a further improvement of the present application, the syngas ratio regulation system of the SOEC stack comprises a safety monitoring unit for monitoring the CH4 concentration and the proportional deviation, and when the CH4 concentration is detected to be > 50ppm or ΔR is continuously > 15%, a four-stage interlock protection is triggered to sequentially perform current cutting, inert gas flushing, intake cutting to a protective gas and uploading of a fault code.

[0032] As a further improvement of the present application, the in-situ gas component detection data and parameter acquisition unit acquires the H2 / CO actual ratio R_actual at the stack outlet and the multi-source operating parameters in real time, and the sampling frequency is ≥ 0.5Hz, and the detection accuracy is ±1%.

[0033] As a further improvement of the present application, the neural network trend prediction model performs the following operations:

[0034] predicting the H2 / CO ratio change trend in a short period of time in the future based on the current R_actual, historical data and multi-source operating parameters;

[0035] dynamically generating the optimal adjustment parameter combination of the intake ratio, the current density, the gas flow rate and the working temperature with the optimization target of minimizing ΔR;

[0036] The multi-source operating parameters include the current R_actual, historical data, temperature, current, flow rate and pressure.

[0037] The synergistic regulation of current density and temperature field is synchronous execution of current density regulation and temperature compensation, and the temperature compensation amount is dynamically calculated according to an electrochemical reaction kinetics model; the internal temperature field distribution of the stack is collected by an embedded thermocouple array.

[0038] The application discloses a SOEC co-electrolysis system for precise proportion regulation of synthesis gas, comprising:

[0039] A SOEC stack core unit is used to realize high-temperature co-electrolysis of CO2 and H2O to directly generate H2 / CO synthesis gas.

[0040] A raw material pretreatment and supply unit is used to pretreat CO2, H2O, CO, H2 and gas mixture, and control the feeding proportion according to the regulation instruction.

[0041] An in-situ gas component detection and feedback unit comprises a ceramic-metal composite probe arranged at the cathode outlet of the stack, and integrates a microfluidic cooling channel, the ceramic-metal composite probe is connected to a multi-point distributed sampling system and a micro Fourier transform infrared-mass spectrometer, detects the component contents of H2 / CO / CO2 / H2O / CH4, and outputs the H2 / CO ratio and component data in real time.

[0042] A heat management unit comprises a microchannel multistage heat exchange network, a chemical waste heat recovery channel and a temperature control module, the temperature control module cooperates with a temperature controller through an embedded thermocouple array installed in the stack core and an external heating element of the stack, so that the axial temperature difference of the stack is stabilized within ±0.8℃.

[0043] A power input and conversion unit integrates an AC-DC conversion module, a precision DC regulation module, a current density dynamic balancing device and an electric energy quality optimizer, and is used to provide DC electric energy for the SOEC stack core unit, the current density dynamic balancing device optimizes the current supply strength of each region based on real-time feedback of the internal temperature field and impedance distribution of the stack.

[0044] An intelligent control and mathematical processing unit executes the synthesis gas proportion regulation method of the SOEC stack as described in any one of the above.

[0045] A product collection and post-processing unit is used to collect, purify, store, regulate and output synthesis gas, and monitor the quality of the synthesis gas.

[0046] The system is a synthesis gas proportional closed-loop control system based on multi-source data real-time feedback and multi-parameter dynamic cooperation. The system directly generates synthesis gas by SOEC synchronous electrolysis of CO2 and H2O, and adopts in-situ gas feedback and multi-parameter cooperative control technology to accurately regulate the H2 / CO ratio to meet the strict requirements of different downstream processes on the composition of synthesis gas. At the same time, the system integrates a heat and electricity cooperative management mechanism to fully utilize the waste heat in the high-temperature electrolysis process, thereby significantly improving the energy utilization efficiency.

[0047] The SOEC stack core unit is the core part of the system, the working temperature of the SOEC stack is maintained in the range of 700-900℃, and by adjusting the current density and gas flow rate, the electrochemical reaction rate and product selectivity can be affected. The in-situ gas component detection and feedback unit realizes high-frequency and high-precision online monitoring of core components such as H2 and CO at the high-temperature outlet, and has spatial distribution monitoring capability, and the data is processed in real time and prediction is provided. The heat management unit optimizes the heat flow and utilization of the system to improve the overall energy efficiency. The power input and conversion unit provides stable and controllable direct current power for the SOEC stack.

[0048] As a further improvement of the present application, the SOEC stack core unit adopts a modular stacking design, and the area of a single cell is 100-200cm 2 , which can flexibly expand the system scale by series and parallel combination. The uniform distribution of gas between single cells is realized through biomimetic flow channels to improve the performance of the stack.

[0049] As a further improvement of the present application, the raw material pretreatment and supply unit adopts independent channel control technology, which can respectively adjust the flow rates of CO2 and H2O, and the feed ratio can be continuously adjusted in the range of 0.2-3.0 to adapt to different synthesis gas demands. Further, the gas mixer included in the raw material pretreatment and supply unit adopts a vortex design to ensure uniform mixing.

[0050] As a further improvement of the present application, the product collection and post-processing unit separates and recovers water from the cooled gas to ensure the reuse of water resources; then removes trace impurities such as sulfides through a purification module. The purified synthesis gas is compressed into a buffer tank. The product quality online analyzer continuously monitors the composition and purity, and the output is matched with the downstream process requirements through precise flow and pressure adjustment devices.

[0051] As a further improvement of the present application, the micro-channel multi-stage heat exchange network includes a first heat exchanger for preheating the reaction gas to 700℃, and a second enhanced fin heat exchanger for generating 550℃ supersaturated steam. The chemical waste heat recovery channel introduces the reaction heat released by the downstream methanol synthesis column at 320-380℃ into the raw material preheating section through a pressurized heat conducting oil circuit to increase the initial temperature of the synthesis gas by 120-150℃.

[0052] Compared with the prior art, the present application has the following advantages:

[0053] Compared with the existing SOEC system relying on static air adjustment, the technical scheme of the present application breaks through the strong coupling limitation of temperature, current density and gas flow rate through an in-situ feedback-multi-parameter collaborative control mechanism, realizes precise regulation of the H2 / CO ratio of synthesis gas, and meets the stringent proportion requirements of methanol synthesis, Fischer-Tropsch synthesis and other processes for raw gas. The synthesis gas proportion regulation system of the SOEC stack of the present application can perform safety interlocking and trend prediction, and automatically trigger a four-stage fusing mechanism when the proportion deviation is >3% or CH4>50ppm through a high-temperature probe and a neural network prediction model, which is shorter than the traditional manual intervention in fault recovery time.

[0054] The SOEC co-electrolysis system for precise regulation of the proportion of synthesis gas of the technical scheme of the present application can integrate an external chemical waste heat recovery channel, etc., and use the downstream 320-380℃ reaction waste heat for raw material preheating, and combine with microchannel cascade heat exchange to improve the overall energy efficiency. The system adopts a modular architecture, supports multi-scene rapid adaptation of fuel cells / chemical synthesis, etc., and provides a standardized technical platform for "on-demand gas" driven by renewable energy. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 is a flow chart of the synthesis gas proportion regulation method of the SOEC stack of the embodiment of the present application.

[0056] Figure 2 is an architectural schematic diagram of the SOEC co-electrolysis system for precise regulation of the proportion of synthesis gas of the embodiment of the present application. DETAILED DESCRIPTION

[0057] The preferred embodiments of the present application will be further described in detail below.

[0058] Since the proportion of synthesis gas generation is affected by many factors such as temperature, current density, fuel ratio, reaction type, catalytic activity, etc., manual adjustment of the proportion of the inlet gas is used for regulation, which has low precision and response lag; and lacks real-time gas component feedback and multi-parameter collaborative control mechanism, it is difficult to dynamically adapt to downstream demand, and the lack of integration and intelligence also restricts the operation economy. Based on the system architecture and experimental data, the synthesis gas proportion precise regulation method of the present application realizes dynamic optimization through closed-loop feedback-intelligent decision-making-multi-parameter collaborative mechanism.

[0059] As shown in Figure 1 , the synthesis gas proportion regulation method of the SOEC stack comprises the following steps:

[0060] 1. Target proportion setting and working condition initialization

[0061] According to the downstream process requirements (such as methanol synthesis requires H2 / CO ≈ 2:1, Fischer-Tropsch synthesis requires ≈ 2.1:1), set the target ratio value R_target in the data processing unit. The system initialization parameters prefer to use the experimental optimization working condition: working temperature 800℃, fuel utilization rate 85%, air according to the fuel extreme flow is set to 2 times the proportion.

[0062] 2. In-situ feedback and dynamic compensation decision

[0063] Data acquisition: the in-situ gas detection unit acquires the actual H2 / CO ratio R_actual at the stack outlet every 2 seconds in real time; the sampling frequency is ≥0.5Hz, and the accuracy is ±1%.

[0064] At the same time, the system continuously collects other key operating parameters: the internal temperature field distribution of the stack (through the embedded thermocouple array), the current density, the system impedance spectrum, the gas flow rate, the system pressure, etc.

[0065] Deviation analysis: the data processing unit calculates ΔR = |R_actual - R_target|, and generates a third-order control strategy:

[0066] Primary control (ΔR≤3%): fine-tune the system disturbance, mainly adjust the inlet gas ratio H2O / CO2, use small step adjustment, each adjustment step ≤5vol%, to quickly eliminate small deviations and maintain stable system operation.

[0067] Secondary control (3%<ΔR≤10%): start multi-parameter collaborative adjustment. Based on the electrochemical reaction kinetics model (implicit in the decision logic of the data processing unit), adjust the current density and temperature field collaboratively. The current density is adjusted by 0.05A / cm 2 Step increase and decrease, and the temperature field is compensated within ±20℃ to assist the current adjustment effect. During the temperature adjustment process, it is necessary to ensure that the axial temperature difference of the stack is stable at ≤0.8℃ to prevent thermal stress damage. This level of control can deal with moderate deviations, and effectively correct them by using the synergistic effect of current (directly affecting the reaction rate) and temperature (affecting the reaction kinetics and equilibrium).

[0068] Tertiary control (ΔR>10%): start multi-variable coupled adjustment, activate the trend prediction model based on neural network, the neural network model analyzes multiple source information such as current R_actual, historical data, temperature, current, flow rate, pressure, etc., and predicts the future short-term (for example, several seconds to tens of seconds) H2 / CO ratio change trend. Based on the prediction results and optimization target (minimize ΔR), the model dynamically calculates the optimal combination of adjustment parameters, and adjusts the feed ratio H2O / CO2, current density I, gas flow rate Flow, working temperature T, and other related parameters such as fine-tuning pressure as needed.

[0069] The fast correction of major deviations at this level regulates the system to quickly restore stable operation and avoid system instability or oscillation caused by sudden changes in a single parameter (such as a large change in intake or current), achieving smooth, fast, and accurate convergence to the target ratio.

[0070] 3. Execution mechanism under constraints

[0071] All regulatory actions (at any level) must strictly follow the preset thermal-electric-gas coupling safety boundaries, which are hard constraints for algorithm execution: temperature gradient ≤ 5K / cm (to prevent local overheating or thermal stress); fuel utilization (FU) ∈ [70%, 90%] (to ensure reaction efficiency); current density ≤ 1A / cm 2 (to protect the stack); temperature change rate ≤ 4K / min (to prevent thermal shock). When calculating the adjustment command, the algorithm verifies whether the command violates the above constraints in real time. If it violates, the safety constraints are prioritized, and higher-level regulation or safety response may be triggered.

[0072] 4. Abnormal fusing and quality traceability

[0073] This is a key safety mechanism that runs independently of the regulation cycle but in parallel. If CH4 concentration > 50ppm or ratio deviation > 15% is detected, four interlocks are triggered: current cutoff → inert gas flushing → feed cut to protective gas → upload fault code. Compared with traditional manual intervention, the fault recovery time is shorter.

[0074] The embodiment of the present application discloses a SOEC co-electrolysis system for precise regulation of syngas ratio. The system directly generates syngas by synchronously electrolyzing CO2 and H2O through SOEC, and adopts the syngas ratio regulation method of the SOEC stack as described above. Through in-situ gas feedback and multi-parameter collaborative control technology, precise regulation of H2 / CO ratio is achieved, meeting the strict requirements of different downstream processes on syngas composition. At the same time, the system integrates a thermal-electricity collaborative management mechanism, fully utilizes the waste heat in the high-temperature electrolysis process, and significantly improves energy utilization efficiency.

[0075] The SOEC co-electrolysis system for precise regulation of syngas ratio is a syngas ratio closed-loop control system based on multi-source data real-time feedback and multi-parameter dynamic collaboration, mainly composed of seven functional units, including: SOEC stack core unit, raw material pretreatment and supply unit, in-situ gas component detection and feedback unit, heat management unit, power input and conversion unit, intelligent control and mathematical processing unit, and product collection and post-processing unit. Each unit is tightly coupled through material flow, energy flow and information flow, forming a highly integrated intelligent system. The overall architecture of the system adopts modular design, as shown in Figure 2 .

[0076] SOEC stack core unit is the core part of the system, responsible for the high-temperature co-electrolysis of CO2 and H2O, directly generating H2 / CO synthesis gas. SOEC stack operating temperature is maintained in the range of 700-900℃, by adjusting the current density (0-1A / cm 2 ) and gas flow rate, the electrochemical reaction rate and product selectivity can be affected. The stack uses a modular stack design, a single cell area of 100-200cm 2 , through the combination of series and parallel, the system size can be flexibly expanded. The gas is uniformly distributed between the single cells through the biomimetic flow channel, improving the performance of the stack.

[0077] Raw material pretreatment and supply unit is responsible for the pretreatment of CO2, H2O, CO, H2 and gas blending, and accurate control of the feed ratio. This unit uses independent channel control technology, which can adjust the flow of CO2 and H2O respectively, and the feed ratio can be continuously adjusted in the range of 0.2-3.0, which is suitable for different synthesis gas demand. The gas mixer in it uses vortex design to ensure uniform mixing.

[0078] In-situ gas component detection and feedback unit realizes high-frequency and high-precision online monitoring of core components such as H2 and CO at high-temperature outlet, and has spatial distribution monitoring capability, data real-time processing and prediction. The unit is installed with high-temperature resistant ceramic-metal composite probe at the cathode outlet of each SOEC stack and at the outlet of different stack cathode gas collection, which is embedded with microfluidic cooling channel, which can reduce the gas to 50-100℃ analysis temperature interval within 0.5 seconds in 900℃ environment; The probe is connected to a multi-point distributed sampling system, which realizes automatic switching monitoring of different stack outlets through an electromagnetic valve array, accurately evaluates the uniformity of the reaction, and evaluates the working state of a single stack, providing a basis for system fault diagnosis. Gas analysis uses a micro Fourier transform infrared spectrometer combined with a mass spectrometer, which can simultaneously detect H2 / CO / CO2 / H2O components with ±1% accuracy and <2 seconds response speed; After data real-time filtering and outlier rejection processing by high-speed acquisition module, the trend prediction algorithm based on neural network is input to predict the component change trend in advance. All data are displayed in real time through a visual industrial control interface, and when the H2 / CO ratio deviation is >±3% or dangerous components (such as CH4) are detected, the four-stage safety interlock of current cut-off-inert gas flushing-fault code uploading is started immediately. This design breaks through the spatial limitations and lag defects of traditional single-point sampling, and establishes a millisecond-level feedback channel for synthesis gas ratio closed-loop control.

[0079] The heat management unit optimizes the system thermal energy flow and utilization, improving overall energy efficiency. The unit is based on a micro-channel multi-stage heat exchange network, achieving high-temperature thermal energy cascade recovery - a primary heat exchanger preheats the reaction gas to 700°C, and a secondary enhanced fin heat exchanger generates super-saturated steam at 550°C. The unit also innovatively integrates chemical waste heat recovery channels, which guide the 320-380°C reaction heat released by the downstream methanol synthesis tower into the raw material preheating section through a pressurized heat transfer oil circuit, increasing the initial temperature of the synthesis gas by 120-150°C, reducing the energy consumption of the auxiliary heating of the stack, and simultaneously driving the organic Rankine cycle unit to generate electricity with the surplus heat. The temperature control system, through the embedded thermocouple array installed in the core of the stack and the external heating elements in cooperation with the precision temperature controller, stabilizes the axial temperature difference of the stack within ±0.8°C, achieving precise control of the stack temperature and avoiding damage to the stack caused by thermal stress. The heat management unit deeply integrates external chemical waste heat recovery channels, using the downstream 320-380°C reaction waste heat for raw material preheating, and combining micro-channel cascade heat exchange to improve overall energy efficiency.

[0080] The power input and conversion unit provides stable and controllable direct current power for the SOEC stack. The unit is configured with a high-compatibility AC / DC conversion system at the front end, seamlessly connecting to the power grid or wind-solar-storage energy sources. The middle section realizes wide-range smooth control of the stack voltage through a precision DC regulation module. It also integrates a current density dynamic balancing device, based on real-time feedback of the internal temperature field and impedance distribution of the stack, to automatically optimize the current supply strength of each region to extend the service life. A power quality optimizer is deployed simultaneously to suppress grid fluctuation interference, and a multi-stage safety protection mechanism with millisecond-level response is used to prevent overload risks, ensuring the stability of power supply and the optimal energy efficiency of the hydrogen / synthesis gas process under renewable energy fluctuations.

[0081] The intelligent control and mathematical processing unit, as the core hub of the system, receives real-time multi-source data from gas detection (component ratio), thermoelectric management (temperature field distribution), and the power unit (current density, impedance spectrum). Based on these data, it calculates the current H2 / CO actual value in real time and compares it with the set target value to determine the deviation direction and amplitude. Based on the pre-set control model or multi-objective optimization algorithm, it dynamically calculates the optimal adjustment strategy for parameters such as feed ratio, current density, temperature field, gas flow rate, and system pressure, based on the current state and predicted trends. It also has the ability to issue trigger commands to the safety system when detecting dangerous signals (such as CH4 exceeding the standard, abnormal sharp temperature rise, and severe deviation of the ratio), and to diagnose the health status of the system based on temperature / voltage / impedance characteristics. The intelligent control and mathematical processing unit executes the synthesis gas ratio control method for the SOEC stack as described above.

[0082] The product collection and post-processing unit is responsible for collecting, purifying, storing, conditioning, and outputting the syngas while monitoring its quality. This unit performs water separation and recovery from the cooled gas, ensuring the reuse of water resources; then removes trace impurities such as sulfides through a purification module. The purified syngas is compressed into a buffer tank. An online product quality analyzer continuously monitors the composition and purity, and the output is matched to the downstream process requirements through precise flow and pressure regulation devices.

[0083] The SOEC co-electrolysis system of the present embodiment directly generates syngas by synchronously electrolyzing CO2 and H2O through SOEC, and adopts an in-situ feedback-multiple parameter collaborative control mechanism, breaking through the strong coupling limitation of temperature, current density, and gas phase flow rate, realizing precise regulation of the H2 / CO ratio of syngas, and meeting the stringent proportion requirements of different downstream processes such as methanol synthesis and Fischer-Tropsch synthesis for raw gas. At the same time, the system integrates a thermal-electricity collaborative management mechanism, fully utilizes the waste heat in the high-temperature electrolysis process, and significantly improves the energy utilization efficiency.

[0084] The above is a further detailed description of the present application in combination with specific preferred embodiments, and the specific implementation of the present application cannot be limited to these descriptions. For ordinary skilled persons in the technical field to which the present application belongs, without departing from the concept of the present application, a number of simple deductions or substitutions can be made, which should be considered as falling within the protection scope of the present application.

Claims

1. Method for syngas ratio control of a SOEC stack, characterized in that Comprising the following steps: Step S1, target setting and initialization: set the target H2 / CO ratio value R_target according to the downstream process requirements, and initialize the working parameters to the preset working condition; Step S2, real-time acquisition of H2 / CO actual ratio R_actual at the stack outlet and multi-source operating parameters, the multi-source operating parameters including temperature field distribution, current density, impedance spectrum, gas flow rate and system pressure; Step S3, calculate the proportional deviation ΔR = | R _actual-R_target|, execute the following hierarchical control: When ΔR < 3%, adjust the H2O / CO2 ratio of the inlet gas, and the single adjustment step is ≤5vol%; When 3% < ΔR ≤ 10%, based on electrochemical reaction kinetics model, synergistically regulate current density and temperature field, the current density is 0.05 A / cm 2 Step up or down, the temperature field in the range of ± 20 °C compensation, and maintain the axial temperature difference of the stack ≤ 0.8 °C; When ΔR > 10%, activate the neural network trend prediction model, analyze and predict the H2 / CO ratio change trend according to the multi-source operating parameters, and dynamically optimize the combined parameters of the H2O / CO2 inlet gas ratio, current density, gas flow rate and working temperature; All the regulation actions should follow the pre-set thermo-electro-gas coupling safety boundaries, including: temperature gradient ≤ 5 K / cm, fuel utilization ∈ [70%, 90%], current density ≤ 1 A / cm 2 , temperature change rate ≤ 4 K / min; if the regulation instruction violates any of the constraints of the thermo-electro-gas coupling safety boundaries, the regulation action that satisfies the safety constraints is preferred, and a higher-level regulation or safety response is triggered.

2. The method of syngas ratio control of a SOEC stack according to claim 1, characterized in that, Also comprising: When CH4 concentration > 50ppm or ΔR continues to be > 15%, trigger a four-stage interlock protection, and execute current cutoff, inert gas flushing, feed cutting to protection gas and uploading fault coding in turn.

3. The method of syngas ratio control for a SOEC stack of claim 1, wherein: In step S2, the sampling frequency of the real-time acquisition of H2 / CO actual ratio R_actual at the stack outlet and multi-source operating parameters is ≥0.5Hz, and the detection accuracy is ±1%.

4. The method of syngas ratio control for a SOEC stack of claim 1, wherein: In step S3, the neural network trend prediction model performs the following operations: Based on the current R_actual, historical data and multi-source operating parameters, predict the H2 / CO ratio change trend in the future short period; With the optimization goal of minimizing ΔR, dynamically generate the optimal adjustment parameter combination of the inlet gas ratio, current density, gas flow rate and working temperature; The multi-source operating parameters include current R_actual, historical data, temperature, current, flow rate and pressure.

5. The method of syngas ratio control for a SOEC stack of claim 1, wherein: In step S3, the cooperative adjustment of current density and temperature field is synchronous execution of current density adjustment and temperature compensation, and the temperature compensation amount is dynamically calculated according to the electrochemical reaction kinetics model; the temperature field distribution inside the stack is collected by embedded thermocouple array.

6. A syngas proportioning system for a SOEC stack, characterized in that Comprising: A target setting and initialization unit for setting the target H2 / CO ratio value R_target according to the downstream process requirements, and initializing the working parameters to the preset working condition; The in-situ gas component detection data and parameter acquisition unit is used for real-time acquisition of H2 / CO actual ratio R_actual at the stack outlet and multi-source operating parameters; A data processing and control execution unit for calculating the ratio deviation ΔR = |R_actual - R_target|, and performing the following hierarchical control: when ΔR ≤ 3%, adjust the H2O / CO2 ratio of the inlet gas, and the single adjustment step is ≤5vol%; When 3% < ΔR ≤ 10%, based on electrochemical reaction kinetics model, synergistically regulate current density and temperature field, the current density is 0.05 A / cm 2 Step up or down, the temperature field in the range of ± 20 °C compensation, and maintain the axial temperature difference of the stack ≤ 0.8 °C; When ΔR > 10%, activate the neural network trend prediction model, analyze and predict the H2 / CO ratio change trend according to the multi-source operating parameters, and dynamically optimize the combined parameters of the H2O / CO2 inlet gas ratio, current density, gas flow rate and working temperature; And make all regulatory action must follow the pre-set thermal-electric-gas coupling safety boundary, including: temperature gradient ≤5K / cm, fuel utilization ∈[70%, 90%], current density ≤1A / cm 2 , temperature change rate ≤4K / min.

7. The syngas proportioning system of a SOEC stack according to claim 6, characterized in that, Comprising: A safety monitoring unit is configured to monitor CH4 concentration and proportional deviation. When CH4 concentration > 50 ppm or ΔR > 15% is detected, a four-stage interlock protection is triggered, and current cut-off, inert gas flushing, feed cut to protective gas and uploading of fault codes are sequentially performed.

8. The syngas proportioning system of the SOEC stack according to claim 6, characterized in that: The in-situ gas component detection data and parameter acquisition unit acquires H2 / CO actual ratio R_actual at the stack outlet and multi-source operating parameters at a sampling frequency of ≥ 0.5 Hz, with a detection accuracy of ± 1%; The neural network trend prediction model performs the following operations: Based on the current R_actual, historical data and multi-source operating parameters, the H2 / CO ratio change trend in the future short period is predicted; With the optimization target of minimizing ΔR, the optimal adjustment parameter combination of the gas inlet ratio, current density, gas flow rate and working temperature is dynamically generated; The multi-source operating parameters include current R_actual, historical data, temperature, current, flow rate and pressure; The coordinated adjustment of current density and temperature field is performed synchronously with current density adjustment and temperature compensation, and the temperature compensation amount is dynamically calculated according to the electrochemical reaction kinetics model; the temperature field distribution inside the stack is acquired by the embedded thermocouple array.

9. A SOEC co-electrolysis system for precise syngas ratio regulation, characterized in that, It comprises: A SOEC stack core unit for realizing high-temperature co-electrolysis of CO2 and H2O to directly generate H2 / CO synthesis gas; A raw material pretreatment and supply unit for pretreating CO2, H2O, CO, H2 and gas mixture and controlling the feed ratio according to the control instruction; An in-situ gas component detection and feedback unit comprising a ceramic-metal composite probe arranged at the cathode outlet of the stack and integrated with a microfluidic cooling channel, the ceramic-metal composite probe being connected to a multi-point distributed sampling system and a micro Fourier transform infrared-mass spectrometer for detecting H2 / CO / CO2 / H2O / CH4 component content and real-time output of H2 / CO ratio and component data; A heat management unit comprising a microchannel multi-stage heat exchange network, a chemical waste heat recovery channel and a temperature control module, the temperature control module being cooperated with the embedded thermocouple array installed in the stack core and the external heating element of the stack and the temperature controller to stabilize the axial temperature difference of the stack; A power input and conversion unit integrated with an AC-DC conversion module, a precision DC regulation module, a current density dynamic balancing device and an electric energy quality optimizer for providing DC power for the SOEC stack core unit, the current density dynamic balancing device being based on real-time feedback of the temperature field and impedance distribution inside the stack to optimize the current supply strength of each region; An intelligent control and mathematical processing unit for performing the synthesis gas ratio control method of the SOEC stack as claimed in any one of claims 1-5; A product collection and post-treatment unit for collecting, purifying, storing, adjusting and outputting the synthesis gas while monitoring its quality.

10. The SOEC co-electrolysis system for precise syngas ratio control according to claim 9, characterized in that, It comprises: The micro-channel multi-stage heat exchange network comprises a first-stage heat exchanger for preheating reaction gas to 700 DEG C, and a second-stage enhanced fin heat exchanger for generating 550 DEG C supersaturated steam, and the chemical waste heat recovery channel is formed by introducing the 320-380 DEG C reaction heat released from the downstream methanol synthesis tower into the raw material preheating section through a pressurized heat conducting oil loop, so that the initial temperature of the synthesis gas is increased by 120-150 DEG C.

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