An air separation system utilizing abandoned wind and light green electricity coupled battery energy storage

Abstract

The present application relates to the technical field of energy storage, in particular to a kind of air separation system using abandoned wind and light green electricity coupling battery energy storage.The system includes new energy power generation module, battery energy storage module, power dispatching control unit, energy management and optimization module and air separation device module.Power dispatching control unit monitors new energy power generation output, battery energy storage state of charge and grid price in real time;Energy management and optimization module executes scheduling strategy according to monitoring data: when abandoned wind and light, green electricity is used to drive air separation device first and redundant power is stored to battery, when new energy output is insufficient, power is supplied by battery, when energy storage is insufficient, power is supplied by cutting into grid;Air separation device keeps rated or slowly varying load continuous operation under each power supply mode.The present application efficiently uses abandoned wind and light green electricity, reduces electricity cost, guarantees power supply stability through the buffering effect of battery energy storage, avoids rectifying column operating condition fluctuation, improves product purity and operation reliability.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to an air separation system that utilizes curtailed wind and solar power coupled with battery energy storage. Background Technology

[0002] Air separation systems (AS) are key industrial devices in fields such as coal chemical engineering, steel smelting, and electronics manufacturing. They separate nitrogen, oxygen, argon, and other components from the air through cryogenic distillation. Their operation is highly dependent on a continuous and stable power supply, and the compressor units often have power ratings of several thousand kilowatts. Electricity costs account for more than 60% of the total operating costs. Among related technologies, with the increasing proportion of wind and solar power in the power structure, the phenomenon of wind and solar curtailment is becoming increasingly prominent. Energy storage systems have become a key means of absorbing this green electricity. Specifically, existing AS systems attempt to adapt to electricity price fluctuations by increasing load to produce liquid products during off-peak hours and reducing load to consume liquids during peak hours. However, this model relies on the peak-valley price difference in the power grid and does not directly utilize the zero marginal cost advantage of curtailed wind and solar green electricity.

[0003] However, existing air separation energy storage solutions directly employ a single liquid-air recirculation route without integrating battery energy storage modules as independent energy storage carriers with the renewable energy generation modules. This can lead to frequent load changes causing fluctuations in the distillation column's operating conditions, affecting product purity and yield stability. Furthermore, liquid-air recirculation requires the laying of cryogenic pipelines and the installation of numerous safety accessories, resulting in high engineering costs and significant safety risks. In addition, existing technologies lack mechanisms to address the inherent intermittency and volatility of wind and solar power curtailment, failing to guarantee the continuous and stable operation of the air separation unit under power supply fluctuations, thus limiting the absorption capacity of renewable energy and the overall economic benefits of the system. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problems of low utilization rate of wind and solar curtailment green electricity, poor power supply stability, and fluctuations in air separation operating conditions caused by variable load operation in the prior art.

[0005] To address the aforementioned technical problems, this invention provides an air separation system that utilizes curtailed wind and solar power coupled with battery energy storage, comprising:

[0006] New energy power generation module; Battery energy storage module; The power dispatch control unit is used to monitor the power output of the new energy power generation module, the state of charge of the battery energy storage module, and the grid electricity price information in real time. The energy management and optimization module is used to execute scheduling strategies based on monitoring data from the power dispatch control unit: when the power output of the new energy generation module is higher than the real-time power demand of the air separation unit module, it is determined to be a period of wind and solar curtailment, and all the green electricity generated by the new energy generation module is prioritized to drive the operation of the air separation unit module, and the redundant energy is stored in the battery energy storage module; when the power output of the new energy generation module is lower than the real-time power demand of the air separation unit module but the state of charge of the battery energy storage module is higher than a preset threshold, the battery energy storage module is controlled to release stored energy to supplement power supply and maintain the continuous operation of the air separation unit module within the rated power range; when the state of charge of the battery energy storage module is lower than the preset threshold and the power output of the new energy generation module is still insufficient, the module switches to grid power supply mode to ensure the continuous operation of the air separation unit module. The air separation unit module is used to maintain rated operation or slowly changing load operation under various power supply modes to continuously perform air separation operations. The air separation unit module includes a raw material air filtration unit, a multi-stage air compressor unit, a pre-cooling purification unit, a main heat exchange unit, and a distillation separation unit. The air separation operation includes: the raw material air is filtered by the raw material air filtration unit and then enters the multi-stage air compressor unit to be compressed to a set pressure. The compressed air is cooled and water and carbon dioxide are removed by the pre-cooling purification unit and then enters the main heat exchange unit for further cooling to near the liquefaction temperature. The low-temperature air is sent to the distillation separation unit for low-temperature distillation separation to obtain nitrogen, oxygen, and argon products, respectively.

[0007] Preferably, the power dispatch control unit monitors the power output of the new energy power generation module in real time, including: Power sensors deployed at the grid connection points of wind turbine generators and photovoltaic power generation arrays collect active power data in real time, and transmit the active power data to the data acquisition module of the power dispatch control unit via a communication bus to generate the real-time output curve of the new energy power generation module.

[0008] Preferably, the energy management and optimization module executes a scheduling strategy based on monitoring data, including: The energy management and optimization module receives the power output of the new energy generation module, the state of charge of the battery energy storage module, and the grid electricity price information transmitted by the power dispatch control unit. Based on the preset priority logic, it determines the current power supply mode and sends the power supply mode switching command to the power electronic switch array of the power dispatch control unit to execute the automatic switching between the new energy green electricity power supply mode, the battery energy storage power supply mode, and the grid power supply mode.

[0009] Preferably, the energy management and optimization module determines the current power supply mode based on preset priority logic, including: The energy management and optimization module compares the power output of the new energy power generation module with the real-time power demand of the air separation unit module. When the power output is greater than or equal to the real-time power demand, the module generates the new energy green electricity power supply mode instruction. When the power generation output is less than the real-time power demand and the state of charge of the battery energy storage module is higher than the preset threshold, the battery energy storage power supply mode command is generated. When the power generation output is less than the real-time power demand and the state of charge of the battery energy storage module is lower than the preset threshold, the grid power supply mode command is generated.

[0010] Preferably, the period when the power output of the new energy power generation module is higher than the real-time power demand of the air separation unit module is determined to be a period of wind and solar curtailment includes: The energy management and optimization module compares the real-time power output of the new energy power generation module with the rated power limit of the air separation unit module. When the real-time power output exceeds the rated power limit and the excess portion continues to exceed a preset time threshold, it determines that the current period is a wind and solar curtailment period and triggers the redundant energy storage process.

[0011] Preferably, storing redundant electrical energy in the battery energy storage module includes: The power dispatch control unit controls the DC-DC converter of the battery energy storage module to convert the redundant green electricity generated by the new energy power generation module into DC electricity that is compatible with the charging voltage of the battery energy storage module, according to the energy storage instructions issued by the energy management and optimization module, and charges the electrochemical energy storage battery pack according to the constant current and constant voltage charging strategy set by the battery management system.

[0012] Preferably, the supplementary power supply provided by releasing stored electrical energy from the battery energy storage module includes: According to the discharge command issued by the energy management and optimization module, the power dispatch control unit controls the DC-AC inverter of the battery energy storage module to convert the DC power stored in the electrochemical energy storage battery pack into AC power that matches the power supply voltage and frequency of the air separation unit module, and then combines it with the output of the new energy power generation module to jointly drive the operation of the air separation unit module.

[0013] Preferably, the grid connection power supply mode includes: According to the power grid input command issued by the energy management and optimization module, the power dispatch control unit closes the grid connection switch connected to the power grid input terminal and disconnects the discharge circuit of the battery energy storage module, so that the air separation unit module is completely powered by the grid and maintains the air separation unit module in continuous operation within the rated power range.

[0014] Preferably, the air separation unit module maintains rated operation or gradually changing load operation under various power supply modes, including: The energy management and optimization module sends a load adjustment command to the variable frequency drive of the multi-stage air compressor unit according to the power supply mode switching signal, so that the multi-stage air compressor unit can be gradually adjusted within the set range of rated speed to maintain the stable gas-liquid balance between the rising gas and the reflux liquid in the distillation column of the distillation separation unit.

[0015] Preferably, the air separation system further includes a liquid product storage tank connected to the air separation unit module for storing the liquid product produced by the distillation separation unit. The above-described technical solution of the present invention has the following advantages over the prior art: The air separation system described in this invention, which utilizes curtailed wind and solar power coupled with battery energy storage, achieves direct priority consumption of curtailed wind and solar power and battery storage of redundant energy through the coordinated control of the power dispatch control unit and energy management and optimization modules. It also utilizes the buffer power supply of the battery energy storage module to mitigate the intermittency and volatility of renewable energy generation, while using grid power as a backup. This effectively avoids frequent load changes in the air separation unit while maximizing the utilization of zero-marginal-cost green electricity to significantly reduce electricity costs. It ensures continuous and stable operation of the air separation unit under rated or gradually changing load conditions during power supply mode switching, significantly improving the stability of the gas-liquid balance in the distillation column and product purity. Furthermore, it reduces engineering costs and safety hazards by eliminating the need for a liquid-air backfill cryogenic pipeline. Attached Figure Description

[0016] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein: Figure 1 This is a schematic diagram of the structure of an air separation system that utilizes curtailed wind and solar power coupled with battery energy storage, provided by the present invention. Figure 2 This is a schematic diagram of the structure of an air separation system that utilizes curtailed wind and solar power coupled with battery energy storage, according to one embodiment of the present invention. Detailed Implementation

[0017] The core of this invention is to provide an air separation system that utilizes curtailed wind and solar power coupled with battery energy storage, effectively overcoming the shortcomings of existing technologies such as low utilization rate of curtailed wind and solar power, poor power supply stability, and fluctuations in air separation operating conditions caused by variable load operation.

[0018] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of an air separation system that utilizes curtailed wind and solar power coupled with battery energy storage, provided by the present invention; specifically including: New energy power generation module; Battery energy storage module; The power dispatch control unit is used to monitor the power output of the new energy power generation module, the state of charge of the battery energy storage module, and the grid electricity price information in real time. The energy management and optimization module is used to execute scheduling strategies based on monitoring data from the power dispatch control unit: when the power output of the new energy generation module is higher than the real-time power demand of the air separation unit module, it is determined to be a period of wind and solar curtailment, and all the green electricity generated by the new energy generation module is prioritized to drive the operation of the air separation unit module, and the redundant energy is stored in the battery energy storage module; when the power output of the new energy generation module is lower than the real-time power demand of the air separation unit module but the state of charge of the battery energy storage module is higher than a preset threshold, the battery energy storage module is controlled to release stored energy to supplement power supply and maintain the continuous operation of the air separation unit module within the rated power range; when the state of charge of the battery energy storage module is lower than the preset threshold and the power output of the new energy generation module is still insufficient, the module switches to grid power supply mode to ensure the continuous operation of the air separation unit module. The air separation unit module is used to maintain rated operation or slowly changing load operation under various power supply modes to continuously perform air separation operations. The air separation unit module includes a raw material air filtration unit, a multi-stage air compressor unit, a pre-cooling purification unit, a main heat exchange unit, and a distillation separation unit. The air separation operation includes: the raw material air is filtered by the raw material air filtration unit and then enters the multi-stage air compressor unit to be compressed to a set pressure. The compressed air is cooled and water and carbon dioxide are removed by the pre-cooling purification unit and then enters the main heat exchange unit for further cooling to near the liquefaction temperature. The low-temperature air is sent to the distillation separation unit for low-temperature distillation separation to obtain nitrogen, oxygen, and argon products, respectively.

[0020] In this embodiment, the power dispatch control unit is used to monitor the power output of the new energy generation module, the state of charge of the battery energy storage module, and the grid price information in real time. Specifically, the power dispatch control unit is configured to continuously acquire and update multiple key parameters related to system operation. These parameters include at least the real-time power output of the new energy generation module, the current state of charge of the battery energy storage module, and the real-time grid price information. As an optional implementation, the power dispatch control unit acquires power output data from the power output terminal of the new energy generation module, state of charge data from the management system of the battery energy storage module, and price signals from the grid metering device or the power market information platform through a sensor network, communication interface, and data processing module, thereby achieving periodic or event-triggered acquisition and updating of the above three types of information. Through synchronous monitoring of the above multi-dimensional data, the system can establish a comprehensive understanding of the current power supply environment and the status of energy storage resources, thus laying the necessary preconditions for subsequent selection and switching of power supply modes based on preset strategies.

[0021] In this embodiment, the energy management and optimization module executes a scheduling strategy based on monitoring data from the power dispatch control unit. Specifically, based on real-time monitoring data collected by the power dispatch control unit, the module automatically determines the current power supply and demand condition according to the relative relationship between the instantaneous power output of the renewable energy generation module and the real-time power demand of the air separation unit module, and in conjunction with the state of charge of the battery energy storage module. Based on this, it selects and switches between various power supply modes. When the system detects that the power output of the renewable energy generation module is sufficient to cover or even exceed the real-time power demand of the air separation unit module, it identifies the existence of surplus green electricity. At this time, all the electricity generated by the renewable energy generation module is prioritized for directly driving the air separation unit module, thereby maximizing the local consumption of renewable energy. Simultaneously, the redundant electricity exceeding the real-time power demand of the air separation unit module is directed to the battery energy storage module for storage, thus converting intermittent, instantaneous surplus green electricity into dispatchable chemical energy reserves. When the power output of the renewable energy generation module cannot fully meet the real-time power demand of the air separation unit module, but the state of charge of the battery energy storage module remains above the preset safety threshold, the system will schedule the battery energy storage module to release its previously stored electrical energy to power the air separation unit module together with the output of the renewable energy generation module. This will compensate for the power supply gap and ensure that the air separation unit module can maintain continuous and stable operation within its rated power range. When the state of charge of the battery energy storage module drops below the preset threshold, and the power output of the renewable energy generation module remains insufficient, the system will automatically switch to grid power supply mode, with the grid acting as the final backup power source to supply power to the air separation unit module to prevent shutdown due to power outage.

[0022] In this embodiment, the air separation unit module operates under rated conditions or gradually changing load conditions in various power supply modes to continuously perform air separation operations. Specifically, regardless of whether it is powered directly by the new energy power generation module, powered by the battery energy storage module releasing stored energy, or powered by the grid, the air separation unit module continuously performs air separation operations under rated conditions or gradually changing load conditions. This operation process is essentially a multi-stage physical processing flow, the core of which lies in the gradual purification, compression, cooling, and distillation separation of the raw material air. Specifically, the air separation unit module includes a raw material air filtration unit, a multi-stage air compressor unit, a pre-cooling purification unit, a main heat exchange unit, and a distillation separation unit. First, the raw material air is filtered by the raw material air filtration unit to remove particulate impurities, and then enters the multi-stage air compressor unit to be compressed to the set pressure level required by the process. The compressed high-temperature and high-pressure air enters the pre-cooling purification unit, where it is cooled down and easily condensable impurities such as moisture and carbon dioxide are removed simultaneously to prevent freezing and blockage of subsequent low-temperature equipment. Pre-purified compressed air is then fed into the main heat exchange unit, where it undergoes efficient heat exchange with the reflux cryogenic gas from the distillation separation unit, thereby being further cooled to near its liquefaction temperature. Finally, this near-liquefaction temperature cryogenic air is fed into the distillation separation unit, where nitrogen, oxygen, and argon are efficiently separated through a cryogenic distillation process, utilizing the differences in the boiling points of the air components. These components are then output as product gases. In one specific embodiment, the distillation separation unit may include a lower distillation column, an upper distillation column, and a condenser / evaporator. The cryogenic air is introduced from the bottom of the lower distillation column, and through multi-stage contact and mass and heat transfer between the gas and liquid phases within the column, high-purity nitrogen is obtained at the top of the upper distillation column, and oxygen-enriched liquid air is obtained at the bottom. Further processing yields oxygen and argon products.

[0023] This invention, through the coordinated control of the power dispatch control unit and the energy management and optimization module, achieves the direct priority consumption of curtailed wind and solar power and the battery storage of redundant energy. It also utilizes the buffer power supply of the battery energy storage module to smooth the intermittency and volatility of new energy power generation, while using grid power supply as a backup guarantee. Thus, while maximizing the utilization of zero marginal cost green electricity to significantly reduce electricity costs, it effectively avoids frequent load changes in the air separation unit, ensuring continuous and stable operation of the air separation unit under rated or slowly changing load conditions during the switching of various power supply modes. It significantly improves the stability of gas-liquid balance in the distillation column and product purity, and reduces engineering costs and safety hazards because it eliminates the need for liquid air backfilling cryogenic pipelines.

[0024] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

[0025] Based on the above embodiments, in some embodiments, the power dispatch control unit monitors the power output of the new energy power generation module in real time, including: Power sensors deployed at the grid connection points of wind turbine generators and photovoltaic power generation arrays collect active power data in real time, and transmit the active power data to the data acquisition module of the power dispatch control unit via a communication bus to generate the real-time output curve of the new energy power generation module.

[0026] In this embodiment, the power dispatch control unit monitors the power output of the new energy power generation module in real time as follows: First, a first power sensor is deployed at the grid connection point of the wind turbine generator, and a second power sensor is deployed at the grid connection point of the photovoltaic power generation array. These power sensors are used to collect the active power data of their respective power generation units in real time. Specifically, the active power data is output in analog or digital form, and its sampling frequency can be set according to the system accuracy requirements, such as once per second or once per millisecond. The collected active power data is transmitted to the data acquisition module inside the power dispatch control unit via a communication bus. This communication bus can be an industrial fieldbus, such as Modbus RTU, Profibus, or CAN bus, or an industrial Ethernet protocol, such as Modbus TCP or EtherNet / IP, to ensure the real-time performance and reliability of data transmission. After receiving the active power data from each power sensor, the data acquisition module preprocesses it, including data verification, filtering and noise reduction, and timestamp marking, to eliminate abnormal data points caused by sensor noise or communication interference. The preprocessed active power data is sent to the processor inside the power dispatch control unit. Based on the received timestamped active power data, the processor generates a real-time output curve for the renewable energy generation modules in chronological order. This real-time output curve, with time on the horizontal axis and active power value on the vertical axis, dynamically reflects the power generation trends of wind turbines and photovoltaic arrays at the current moment and over a past period. This real-time output curve serves as a key input parameter for subsequent energy management and optimization modules to execute dispatch strategies, determining whether the current period is one of wind or solar curtailment periods and whether the power generation output of the renewable energy generation modules exceeds the real-time power demand of the air separation unit modules. Through the collaborative work of the power sensors, communication bus, data acquisition modules, and processor deployed at the grid connection point, high-precision and high-real-time monitoring of the renewable energy generation module's output is achieved, providing an accurate data foundation for subsequent power dispatch decisions.

[0027] This specific implementation method uses power sensors deployed at the grid connection point, combined with communication bus transmission and data acquisition module processing, to achieve high-precision real-time monitoring of the power output of the new energy power generation module. This provides reliable data support for the energy management and optimization module to accurately determine the curtailment period of wind and solar power and execute precise power dispatch strategies, thereby ensuring the efficient utilization of curtailed wind and solar green electricity and the stability of power supply in the air separation system.

[0028] Based on the above embodiments, in some embodiments, the energy management and optimization module executes a scheduling strategy based on monitoring data, including: The energy management and optimization module receives the power output of the new energy generation module, the state of charge of the battery energy storage module, and the grid electricity price information transmitted by the power dispatch control unit. Based on the preset priority logic, it determines the current power supply mode and sends the power supply mode switching command to the power electronic switch array of the power dispatch control unit to execute the automatic switching between the new energy green electricity power supply mode, the battery energy storage power supply mode, and the grid power supply mode.

[0029] Furthermore, the energy management and optimization module determines the current power supply mode based on preset priority logic, including: The energy management and optimization module compares the power output of the new energy power generation module with the real-time power demand of the air separation unit module. When the power output is greater than or equal to the real-time power demand, the module generates the new energy green electricity power supply mode instruction. When the power generation output is less than the real-time power demand and the state of charge of the battery energy storage module is higher than the preset threshold, the battery energy storage power supply mode command is generated. When the power generation output is less than the real-time power demand and the state of charge of the battery energy storage module is lower than the preset threshold, the grid power supply mode command is generated.

[0030] In this embodiment, the specific implementation of the energy management and optimization module executing the scheduling strategy based on monitoring data is as follows: The energy management and optimization module first receives real-time power output data from the new energy generation module, state-of-charge data from the battery energy storage module, and grid electricity price information transmitted by the power dispatch control unit. This data, as input signals, is sent to the priority logic judgment unit integrated within the energy management and optimization module. This judgment unit determines the current power supply mode based on preset priority logic. Specifically, the priority logic judgment unit compares the power output value of the new energy generation module with the real-time power demand value of the air separation unit module. When the power output is greater than or equal to the real-time power demand, the judgment unit generates a new energy green electricity power supply mode command; when the power output is less than the real-time power demand and the state of charge of the battery energy storage module is higher than a preset threshold, the judgment unit generates a battery energy storage power supply mode command; when the power output is less than the real-time power demand and the state of charge of the battery energy storage module is lower than a preset threshold, the judgment unit generates a grid power supply mode command. This power supply mode command, as an output signal, is sent to the power electronic switch array in the power dispatch control unit. The power electronic switch array executes corresponding switching actions based on received instructions, thereby automatically switching between renewable energy green power supply mode, battery energy storage power supply mode, and grid power supply mode. For example, when receiving a renewable energy green power supply mode instruction, the power electronic switch array connects the power output terminal of the renewable energy generation module to the power input terminal of the air separation unit module, while simultaneously disconnecting the power supply circuit between the battery energy storage module and the grid; when receiving a battery energy storage power supply mode instruction, the power electronic switch array connects the power output terminal of the battery energy storage module to the power input terminal of the air separation unit module; when receiving a grid power supply mode instruction, the power electronic switch array connects the grid power input terminal to the power input terminal of the air separation unit module. Through the above data reception, logical judgment, and instruction issuance process, the energy management and optimization module achieves precise and automatic control of the power supply mode, ensuring that the air separation unit module can obtain a continuous and stable power supply under different operating conditions.

[0031] This specific implementation method, by introducing a priority logic judgment unit and a power electronic switch array, realizes automatic and precise switching of power supply mode, avoids delays and misjudgments caused by manual intervention, significantly improves the system's response speed and utilization efficiency to curtailed wind and solar green electricity, and at the same time ensures the continuity and stability of power supply to the air separation unit module.

[0032] Based on the above embodiments, in some embodiments, the determination of a period of wind and solar curtailment when the power output of the new energy power generation module is higher than the real-time power demand of the air separation unit module includes: The energy management and optimization module compares the real-time power output of the new energy power generation module with the rated power limit of the air separation unit module. When the real-time power output exceeds the rated power limit and the excess portion continues to exceed a preset time threshold, it determines that the current period is a wind and solar curtailment period and triggers the redundant energy storage process.

[0033] In this embodiment, the energy management and optimization module first acquires real-time power output data from the new energy power generation module. This data is collected in real-time by the power dispatch control unit through monitoring the output power of wind turbine generators and photovoltaic power generation arrays and transmitted to the energy management and optimization module. Simultaneously, the energy management and optimization module retrieves the rated power limit of the air separation unit module. This rated power limit is the maximum total power required for key equipment such as the multi-stage air compressor unit, pre-cooling purification unit, main heat exchange unit, and distillation separation unit to operate under rated conditions. It is typically preset by system design parameters and stored in the configuration database of the energy management and optimization module. The energy management and optimization module compares the real-time power output with the rated power limit. When the real-time power output exceeds the rated power limit, it indicates that the electrical energy generated by the new energy power generation module has exceeded the maximum absorption capacity of the air separation unit module under the current operating conditions, resulting in surplus electrical energy that cannot be fully utilized. To further eliminate misjudgments caused by instantaneous fluctuations in wind speed or sunlight intensity, the energy management and optimization module starts a timer to accumulate the duration for which the real-time power output continuously exceeds the rated power limit. When the duration exceeds a preset time threshold, the energy management and optimization module determines that the current period is a period of wind and solar curtailment. This preset time threshold can be set based on the output fluctuation characteristics of the renewable energy generation module and the load adjustment response time of the air separation unit module. For example, it can be set to a fixed value between 5 and 30 minutes to balance the accuracy of the determination and the response speed. After determining it to be a period of wind and solar curtailment, the energy management and optimization module immediately triggers a redundant energy storage process. The specific execution method of this process is as follows: the energy management and optimization module sends a control command to the power dispatch control unit, instructing it to prioritize allocating all green electricity generated by the renewable energy generation module to the power input terminal of the air separation unit module to drive the air separation unit module to operate within its rated power range. Simultaneously, the redundant energy portion of the real-time power generation exceeding the rated power limit of the air separation unit module is switched to the charging circuit of the battery energy storage module through the power dispatch control unit, allowing the battery energy storage module to receive and store this redundant energy at a constant power or the maximum allowable charging power. Through the above-mentioned judgment and triggering mechanism, the accurate identification of wind and solar curtailment periods and the timely and efficient storage of redundant green electricity are realized, avoiding misoperation caused by fluctuations in new energy power generation, and ensuring that the air separation unit module can prioritize the use of green electricity with zero marginal cost for continuous production during wind and solar curtailment periods.

[0034] This specific implementation method effectively improves the accuracy and anti-interference capability of identifying wind and solar curtailment periods by introducing a comparison between real-time power generation output and the upper limit of rated power, as well as a judgment mechanism based on preset time thresholds. It avoids frequent switching caused by instantaneous fluctuations in new energy power generation, thereby ensuring the stability of the power supply mode of the air separation unit module and the reliability of the redundant energy storage process.

[0035] Based on the above embodiments, in some embodiments, storing redundant electrical energy in the battery energy storage module includes: The power dispatch control unit controls the DC-DC converter of the battery energy storage module to convert the redundant green electricity generated by the new energy power generation module into DC electricity that is compatible with the charging voltage of the battery energy storage module, according to the energy storage instructions issued by the energy management and optimization module, and charges the electrochemical energy storage battery pack according to the constant current and constant voltage charging strategy set by the battery management system.

[0036] In this embodiment, after receiving the energy storage command from the energy management and optimization module, the power dispatch control unit first obtains the target charging power and charging voltage parameters contained in the command. The target charging power is calculated by the energy management and optimization module based on the difference between the real-time power output of the new energy generation module and the real-time power demand of the air separation unit module. Subsequently, the power dispatch control unit sends a control signal to the DC-DC converter of the battery energy storage module. The input of the DC-DC converter is connected to the power output of the new energy generation module, and its output is connected to the charging interface of the electrochemical energy storage battery pack. Based on the received control signal, the DC-DC converter converts the redundant green electricity generated by the new energy generation module from AC to DC power adapted to the charging voltage of the electrochemical energy storage battery pack. Specifically, the DC-DC converter adopts a boost or buck topology and dynamically adjusts its duty cycle based on the current terminal voltage of the electrochemical energy storage battery pack fed back by the battery management system in real time, so that the output voltage is stabilized near the target charging voltage value set by the battery management system. After voltage conversion, the battery management system (BMS) charges the electrochemical energy storage battery pack according to a preset constant current and constant voltage charging strategy. In the initial charging phase, the BMS controls the DC-DC converter to output a constant charging current. This constant current value is determined by the BMS based on the rated capacity and current state of charge of the electrochemical energy storage battery pack. When the terminal voltage of the electrochemical energy storage battery pack rises to the charging limit voltage, the BMS switches to constant voltage charging mode, maintaining the DC-DC converter at this limit voltage output while the charging current gradually decreases. When the charging current drops to a preset termination current threshold, the BMS determines that charging is complete and sends a charging completion signal to the power dispatch control unit. The power dispatch control unit then controls the DC-DC converter to stop outputting power. Through this process, redundant green electricity is efficiently and safely converted into chemical energy and stored in the electrochemical energy storage battery pack, providing energy reserves for subsequent power supply.

[0037] This specific implementation achieves precise and safe storage of redundant green electricity from curtailed wind and solar power through voltage conversion of the DC-DC converter and constant current and constant voltage charging strategy of the battery management system. It avoids battery overvoltage or overcurrent damage that may be caused by direct charging, extends the service life of the battery energy storage module, and ensures the coordination between the energy storage process and the power supply of the air separation unit module.

[0038] Based on the above embodiments, in some embodiments, the step of releasing stored electrical energy from the battery energy storage module to supplement power supply includes: According to the discharge command issued by the energy management and optimization module, the power dispatch control unit controls the DC-AC inverter of the battery energy storage module to convert the DC power stored in the electrochemical energy storage battery pack into AC power that matches the power supply voltage and frequency of the air separation unit module, and then combines it with the output of the new energy power generation module to jointly drive the operation of the air separation unit module.

[0039] In this embodiment, when the energy management and optimization module determines, based on real-time monitoring data, that the power output of the new energy generation module is lower than the real-time power demand of the air separation unit module, and the state of charge of the battery energy storage module is higher than a preset threshold, the energy management and optimization module generates a discharge command and sends it to the power dispatch control unit. Upon receiving the discharge command, the power dispatch control unit first parses the target discharge power value and discharge duration parameters contained in the command, and then sends a control signal to the DC-AC inverter of the battery energy storage module. This DC-AC inverter, as the core component of power conversion, has its input connected to the DC bus of the electrochemical energy storage battery pack, and its output electrically coupled to the power output of the new energy generation module and the power input of the air separation unit module via the AC bus. Under the control signal, the DC-AC inverter starts and performs DC-to-AC conversion. Specifically, the power semiconductor switching devices inside the inverter switch on and off at high frequency according to a pulse width modulation strategy, converting the DC power stored in the electrochemical energy storage battery pack into AC power that matches the supply voltage and frequency of the air separation unit module, for example, converting it into 10kV or 6kV, 50Hz three-phase AC power. After filtering and voltage regulation, the AC power output by the inverter is directly superimposed on the real-time output of the new energy power generation module through the AC bus, and the two together constitute the composite power supply driving the operation of the air separation unit module. During this process, the power dispatch control unit continuously monitors the voltage and frequency on the AC bus and adjusts the output power of the inverter through closed-loop feedback to ensure that the total power supply after superposition just meets the continuous operation requirements of the air separation unit module within its rated power range, thereby avoiding insufficient power supply or deterioration of power quality due to fluctuations in the output of new energy power generation. Through the above control process, the discharge process of the battery energy storage module achieves precise conversion from DC power to AC power, and seamlessly integrates with the output of the new energy power generation module to jointly maintain the stable operation of the air separation unit module.

[0040] This specific implementation method achieves real-time superposition of the output of the battery energy storage module and the new energy power generation module through precise control of the DC-AC inverter. This effectively makes up for the power supply gap caused by the intermittency of new energy power generation, ensures the continuous and stable operation of the air separation unit module under rated operating conditions, and avoids the problems of distillation tower instability and product purity reduction caused by power supply fluctuations.

[0041] Based on the above embodiments, in some embodiments, the grid connection power supply mode includes: According to the power grid input command issued by the energy management and optimization module, the power dispatch control unit closes the grid connection switch connected to the power grid input terminal and disconnects the discharge circuit of the battery energy storage module, so that the air separation unit module is completely powered by the grid and maintains the air separation unit module in continuous operation within the rated power range.

[0042] In this embodiment, the power dispatch control unit continuously receives dispatch instructions from the energy management and optimization module. These instructions are generated based on real-time analysis of the power output of the new energy generation module, the state of charge of the battery storage module, and grid electricity price information. When the energy management and optimization module determines that the state of charge of the battery storage module is below a preset threshold, and the power output of the new energy generation module still cannot meet the real-time power demand of the air separation unit module, it triggers a grid power supply mode switching instruction. This instruction is sent to the power dispatch control unit, which then executes a series of electrical operations. Specifically, the power dispatch control unit first sends a closing signal to the grid-connected switch connected to the grid power input terminal. This grid-connected switch is typically a vacuum circuit breaker or a smart contactor, and its closing action connects the power input terminal of the air separation unit module to the grid circuit. At the same time, the power dispatch control unit sends a disconnect signal to the discharge circuit of the battery storage module. This discharge circuit is equipped with a DC contactor or a solid-state relay. By disconnecting this circuit, the battery storage module stops releasing stored energy to the air separation unit module. The above two actions are designed to be executed synchronously or nearly synchronously to avoid power interruption. After the grid connection switch is closed and the discharge circuit is disconnected, the power input of the air separation unit module is entirely supplied by the power grid, with its supply voltage and frequency provided stably by the grid. In this mode, all electrical equipment in the air separation unit module, including the multi-stage air compressor unit, pre-cooling purification unit, main heat exchange unit, and distillation separation unit, draws power from the grid, thereby maintaining continuous operation of the air separation unit module within its rated power range and ensuring that the operating conditions of the distillation column do not fluctuate. This switching process is automatically completed by the power dispatch control unit without manual intervention, and the switching time is typically in the range of milliseconds to seconds, effectively ensuring the continuity and stability of the power supply to the air separation unit module.

[0043] This specific implementation method, through an automated grid connection mechanism, enables rapid and seamless switching of power supply to the air separation unit modules when neither new energy power generation nor battery energy storage can meet the load demand. This avoids instability in the distillation column and a decrease in product purity caused by power outages, and significantly improves the system's operational reliability and safety under extreme conditions.

[0044] Based on the above embodiments, in some embodiments, the air separation unit module maintains rated operation or slowly changing load operation under various power supply modes, including: The energy management and optimization module sends a load adjustment command to the variable frequency drive of the multi-stage air compressor unit according to the power supply mode switching signal, so that the multi-stage air compressor unit can be gradually adjusted within the set range of rated speed to maintain the stable gas-liquid balance between the rising gas and the reflux liquid in the distillation column of the distillation separation unit.

[0045] In this embodiment, after receiving a power supply mode switching signal from the power dispatch control unit, the energy management and optimization module first generates a corresponding load adjustment command based on the current power supply mode type indicated by the signal, such as switching from a new energy green electricity power supply mode to a battery storage power supply mode, or switching from a grid power supply mode to a new energy green electricity power supply mode. This load adjustment command is sent to the variable frequency drive (VFD) of the multi-stage air compressor unit, which adjusts the speed of the drive motor accordingly. Specifically, the load adjustment command received by the VFD includes a target speed value, which is set to a value within the range of 95% to 105% of the rated speed of the multi-stage air compressor unit. By changing the power frequency output to the drive motor, the VFD smoothly brings the actual speed of the compressor unit closer to the target speed value, thereby achieving gradual load adjustment. During this gradual adjustment process, the compressed air flow rate and pressure output by the multi-stage air compressor unit change slowly. The changed compressed air flows through the subsequent pre-cooling purification unit and the main heat exchange unit before entering the distillation separation unit. Within the distillation column of the distillation separation unit, the gas-liquid balance between the rising gas and the reflux liquid is maintained stably due to the slow changes in the inlet parameters. This avoids drastic fluctuations in the gas-liquid ratio caused by sudden load changes, thus ensuring that the purity and yield of nitrogen, oxygen, and argon products are not significantly affected by power supply mode switching. For example, when the power supply mode switches from grid power to battery storage power, the energy management and optimization module can set the target speed to 98% of the rated speed, and the frequency converter adjusts at a rate of no more than 0.5% of the rated speed per minute, allowing the compressor unit to smoothly transition to the new operating condition within minutes, ensuring the stability of the temperature and concentration fields within the distillation column.

[0046] This specific implementation introduces a variable frequency drive to gradually adjust the load of the multi-stage air compressor unit, enabling the air separation unit to maintain a stable gas-liquid balance in the distillation column during power supply mode switching. This effectively avoids product purity and output fluctuations caused by load fluctuations, and significantly improves the system's operational reliability and product quality consistency under various power supply modes.

[0047] Based on the above embodiments, in some embodiments, the specific implementation process of the raw material air entering the multi-stage air compressor unit for compression to a set pressure after being filtered by an air filtration unit is as follows: The raw material air is first pre-treated by a self-cleaning air filter, which can effectively remove dust particles with a diameter greater than 1 micrometer from the air, ensuring that the cleanliness of the air entering the subsequent compression system meets the process requirements. The filtered clean air then enters the three-stage centrifugal compressor unit for staged compression. Specifically, the inlet of the first-stage compressor receives clean air from the self-cleaning air filter and compresses it to an intermediate pressure of 0.2 to 0.3 MPa, during which the air temperature rises significantly. The outlet of the first-stage compressor is connected to the inlet of the first-stage intercooler, which cools the compressed high-temperature air, reducing its temperature to near ambient temperature to reduce the power consumption of subsequent compression and improve compression efficiency. The cooled air enters the second-stage compressor, which further compresses it to an intermediate pressure of 0.6 to 0.8 MPa. The outlet of the second-stage compressor is also connected to the second-stage intercooler for further cooling of the compressed air. Finally, the air, after secondary cooling, enters the third-stage compressor, which compresses it to a set pressure of 0.8 to 1.0 MPa, thus completing the entire multi-stage compression process. This set pressure is the target pressure to meet the process requirements of subsequent pre-cooling purification, main heat exchange, and distillation separation units. Through staged compression and interstage cooling in the three-stage centrifugal compressor unit, not only is the exhaust temperature of each stage compressor effectively controlled, but the total compression power consumption is also significantly reduced, improving the thermodynamic efficiency of the compressor unit.

[0048] This specific implementation method achieves efficient filtration and staged compression of raw material air by using a combination of a self-cleaning air filter, a three-stage centrifugal compressor unit, and an interstage cooler. This not only ensures the cleanliness of the air entering the air separation unit, but also significantly reduces the energy consumption of the compression process through staged compression and interstage cooling, thereby improving the overall energy efficiency of the system and providing a stable, clean, and appropriately pressurized air source for subsequent air separation operations.

[0049] Based on the above embodiments, in some embodiments, the specific implementation of cooling and removing water and carbon dioxide from compressed air via a pre-cooling purification unit is as follows: First, high-temperature compressed air, compressed to a set pressure by a multi-stage air compressor unit, is input into the air-cooled tower of the pre-cooling purification unit. Inside the air-cooled tower, the compressed air exchanges heat with circulating cooling water from the cooling tower in a counter-current contact manner, reducing the temperature of the compressed air to the range of 10 to 15 degrees Celsius, while some water vapor condenses and precipitates due to the cooling. The compressed air, after being cooled by the air-cooled tower, is then input into a molecular sieve adsorber. This molecular sieve adsorber is filled with 13X type molecular sieves, which utilize their porous structure to selectively adsorb water and carbon dioxide molecules, deeply removing residual water and carbon dioxide from the compressed air. After this adsorption treatment, the dew point of the compressed air is reduced to below -60 degrees Celsius, thereby obtaining dry and pure compressed air. This dry and pure compressed air is then output into the main heat exchange unit for further cooling to approach the liquefaction temperature. The series treatment of cooling by the air-cooled tower and adsorption by the molecular sieve adsorber effectively removes moisture and carbon dioxide from the compressed air, preventing blockage of pipes and equipment due to freezing of moisture and carbon dioxide under low-temperature conditions, and ensuring the stable operation of the distillation separation unit.

[0050] This specific implementation method achieves efficient cooling and purification of compressed air by using a combination of air-cooled tower countercurrent cooling and 13X molecular sieve deep adsorption. This ensures that the compressed air entering the main heat exchange unit and distillation separation unit has an extremely low dew point, thereby effectively preventing the risk of ice blockage and dry ice blockage under low temperature conditions, and significantly improving the reliability and product purity stability of the air separation system during continuous operation.

[0051] Based on the above embodiments, in some embodiments, the specific process of introducing cryogenic air into the distillation separation unit for cryogenic distillation separation is as follows: Cryogenic air, cooled to near its liquefaction temperature by the main heat exchange unit, enters the lower distillation column as feed gas from the feed air inlet at the bottom of the lower distillation column. Inside the lower distillation column, the rising vapor and the liquid returning from the top of the column undergo a thorough heat and mass transfer process on the trays or packing. Specifically, the nitrogen at the top of the lower distillation column rises to a condenser-evaporator located between the top of the lower distillation column and the bottom of the upper distillation column. This condenser-evaporator serves as the core component for heat and mass coupling between the lower and upper distillation columns. Inside it, the nitrogen at the top of the lower distillation column exchanges heat with the liquid oxygen at the bottom of the upper distillation column. The nitrogen is condensed into liquid nitrogen, a portion of which returns to the top of the lower distillation column as reflux liquid to participate in the distillation process in the lower column; the liquid oxygen is evaporated into oxygen and rises to the bottom of the upper distillation column to participate in the distillation process in the upper column, thereby forming a heat and mass coupling cycle between the lower and upper distillation columns. After initial separation in the lower distillation column, high-purity nitrogen is obtained at the top, and oxygen-enriched liquid air is obtained at the bottom. This oxygen-enriched liquid air, used as feed for the next stage of separation, is fed into the middle section of the upper distillation column after throttling and depressurization. Inside the upper distillation column, the oxygen-enriched liquid air undergoes further distillation separation under the action of rising vapor and reflux liquid. After fine separation in the upper distillation column, high-purity nitrogen is obtained at the top, high-purity oxygen is obtained at the bottom, and argon is extracted from its side stream. Through the synergistic effect of the lower and upper distillation columns, continuous and efficient separation of the various components of air is achieved.

[0052] This specific implementation method ensures the stability of the distillation separation process and the purity of the product by clearly defining the thermo-mass coupling cycle between the lower and upper distillation columns based on the condenser-evaporator, as well as the precise flow path of oxygen-enriched liquid air from the lower to the upper column. This provides a reliable distillation process foundation for the system to maintain continuous operation under rated conditions or slowly changing load conditions under the green electricity power supply mode of wind and solar power curtailment.

[0053] Based on the above embodiments, in some embodiments, the energy management and optimization module is further configured to: generate a valley electricity compensation command when the grid electricity price is lower than a preset valley price threshold during non-wind and solar curtailment periods; the power dispatch control unit controls the DC-AC inverter of the battery energy storage module to switch from inverter mode to rectification mode according to the valley electricity compensation command, converting the AC power input from the grid into DC power, and charging the electrochemical energy storage battery pack according to a preset constant current and constant voltage charging strategy through the battery management system.

[0054] In this embodiment, the energy management and optimization module continuously monitors the real-time electricity price signal from the power grid during non-curtailment periods. This signal is obtained through the communication interface between the power dispatch control unit and the power grid dispatch system. When the monitored grid electricity price is lower than a preset off-peak price threshold, the energy management and optimization module determines that it is currently in an off-peak period and generates an off-peak electricity replenishment command. This command is sent to the power dispatch control unit, which controls the DC-AC inverter in the battery energy storage module to switch its operating mode from inverter mode to rectification mode. In rectification mode, the inverter converts the AC power input from the grid into DC power as the charging power source. Simultaneously, the power dispatch control unit establishes communication with the battery management system to obtain parameters such as the current state of charge, individual cell voltage, and temperature of the electrochemical energy storage battery pack in the battery energy storage module. According to a preset constant current and constant voltage charging strategy, the battery management system first charges the electrochemical energy storage battery pack with a constant current. When the battery pack voltage reaches the set charging termination voltage, it automatically switches to a constant voltage charging mode, and the charging current gradually decreases until charging is complete. Throughout the charging process, the battery management system monitors the battery status in real time to ensure charging safety and prevent overcharging. The above process achieves the goal of converting low-cost AC power during off-peak hours into DC power and storing it in the battery energy storage module. This power replenishment process provides sufficient power reserves for prioritizing the use of the battery energy storage module during peak hours, thereby effectively reducing peak power consumption.

[0055] This specific implementation introduces a valley electricity compensation mechanism, enabling the battery energy storage module to be charged at low cost during off-peak hours and then discharged to supply power during peak hours. This significantly reduces the overall electricity cost of the air separation system while improving the utilization efficiency of the battery energy storage module and the economy of the system.

[0056] Based on the above embodiments, in some embodiments, the specific implementation of prioritizing the use of battery energy storage modules to reduce peak electricity consumption is as follows: The energy management and optimization module continuously monitors real-time electricity price signals from the grid during non-curtailment periods. These signals are obtained through the communication interface between the power dispatch control unit and the grid dispatch system. When the energy management and optimization module determines that the grid electricity price is higher than a preset peak price threshold, it further reads the state-of-charge (SOC) data of the battery energy storage module. This data is collected and reported in real-time by the battery management system. If the SOC of the battery energy storage module is higher than a preset discharge threshold, for example, this threshold can be set to 30% to 50% of the battery's rated capacity, to ensure that the battery has sufficient remaining power to support the continuous operation of the air separation unit module during peak price periods, the energy management and optimization module generates a peak electricity discharge command. This command is sent to the power dispatch control unit, which then controls the DC-AC inverter of the battery energy storage module to switch to inverter mode. In inverter mode, the DC power stored in the electrochemical energy storage battery pack is converted into AC power matching the rated voltage and frequency of the air separation unit module by the inverter. Simultaneously, the power dispatch control unit disconnects the air separation unit module from the grid power input, allowing the battery energy storage module to drive the air separation unit module independently. During this process, the energy management and optimization module dynamically adjusts the inverter's output power based on the real-time power demand of the air separation unit module to ensure power supply stability. When the grid electricity price falls below the peak price threshold or the state of charge of the battery energy storage module drops below the discharge threshold, the energy management and optimization module generates a stop-discharge command. The power dispatch control unit then controls the inverter to exit inverter mode and reconnect to the grid power supply mode, thus completing a full peak power substitution power supply cycle.

[0057] This specific implementation method achieves precise control over the discharge timing of the battery energy storage module by introducing a dual judgment mechanism of peak price threshold and discharge threshold. This avoids premature discharge of the battery before the electricity price reaches the economically optimal range, and also prevents insufficient subsequent power supply capacity due to over-discharge of the battery. Its beneficial effects are as follows: During periods without wind or solar power curtailment, the system can automatically identify the grid peak price window and use the low-cost electricity stored by the battery energy storage module during off-peak hours to replace the high-priced grid electricity during peak hours, thereby significantly reducing the electricity cost of the air separation unit module; simultaneously, through precise inverter control and automatic switching of power supply modes, the continuous and stable operation of the air separation unit module is ensured during power supply switching, avoiding fluctuations in the distillation tower's operating conditions caused by power outages.

[0058] Based on the above embodiments, in some embodiments, the air separation system further includes a liquid product storage tank connected to the air separation unit module for storing the liquid products produced by the distillation separation unit.

[0059] like Figure 2Based on the above embodiments, the air separation system of this embodiment includes a new energy power generation module, a battery energy storage module, a power dispatch control unit, an air separation unit module, and an energy management and optimization module. The new energy power generation module specifically includes wind turbine generators and photovoltaic arrays for generating renewable green electricity. The battery energy storage module includes at least one electrochemical energy storage battery pack, whose input end is connected to the power output end of the new energy power generation module. It is used to receive and store surplus electricity generated by the new energy power generation module during periods of wind and solar power curtailment, and to supply power to the air separation unit load according to the system operating conditions. The power dispatch control unit is connected to the power output ends of the new energy power generation module, the battery energy storage module, and the grid power input end, respectively. It is used to monitor the new energy power generation output, the battery energy storage state of charge, and the grid electricity price signal in real time, and automatically switch between the new energy green electricity supply mode, the battery energy storage supply mode, and the grid power supply mode according to a preset dispatch strategy to ensure a continuous and stable power supply to the air separation unit. The power input end of the air separation unit module is connected to the output end of the power dispatch control unit and is driven by the power allocated by the dispatch control unit. The energy management and optimization module communicates with the power dispatch control unit and is used to dynamically adjust the load allocation of the multi-stage air compressor unit and the charging and discharging strategy of the battery energy storage module based on wind and solar curtailment forecast information, battery energy storage status information and grid electricity price information.

[0060] In terms of data acquisition and preprocessing, the power dispatch control unit collects active power data in real time through power sensors deployed at the grid connection points of wind turbine generators and photovoltaic power generation arrays. This active power data is then transmitted via a communication bus to the data acquisition module of the power dispatch control unit to generate real-time output curves for the new energy power generation modules. Simultaneously, the power dispatch control unit also acquires real-time state-of-charge data from battery energy storage modules through the battery management system and obtains real-time grid electricity price information through a communication interface with the grid dispatch system. This monitoring data is continuously transmitted to the energy management and optimization modules as input for the execution of dispatch strategies.

[0061] In terms of core scheduling logic, the energy management and optimization module executes scheduling strategies based on received monitoring data. Specifically, the energy management and optimization module compares the real-time power output of the renewable energy generation module with the rated power limit of the air separation unit module. When the real-time power output exceeds the rated power limit and the excess exceeds a preset time threshold, it determines that the current period is one of wind and solar curtailment and triggers the redundant energy storage process. At this time, the energy management and optimization module generates a renewable energy green electricity supply mode instruction, prioritizing the use of all green electricity generated by the renewable energy generation module to drive the air separation unit module, and storing the redundant energy in the battery energy storage module. During the process of storing the redundant energy in the battery energy storage module, the power dispatch control unit, according to the energy storage instruction issued by the energy management and optimization module, controls the DC-DC converter of the battery energy storage module to convert the redundant green electricity generated by the renewable energy generation module into DC electricity adapted to the charging voltage of the battery energy storage module, and charges the electrochemical energy storage battery pack according to the constant current and constant voltage charging strategy set by the battery management system. When the output of the renewable energy generation module is lower than the real-time power demand of the air separation unit module, but the state of charge of the battery energy storage module is higher than a preset threshold, the energy management and optimization module generates a battery energy storage power supply mode command, in which the battery energy storage module releases its stored energy to supplement power supply. Specifically, according to the discharge command issued by the energy management and optimization module, the power dispatch control unit controls the DC-AC inverter of the battery energy storage module to convert the DC power stored in the electrochemical energy storage battery pack into AC power that matches the supply voltage and frequency of the air separation unit module. This AC power is then combined with the output of the renewable energy generation module to jointly drive the air separation unit module, thereby maintaining the continuous operation of the air separation unit module within its rated power range. When the state of charge of the battery energy storage module is lower than the preset threshold and the output of the renewable energy generation module is still insufficient, the energy management and optimization module generates a grid power supply mode command, switching to grid power supply mode to ensure the continuous operation of the air separation unit module. Specifically, the power dispatch control unit closes the grid connection switch connected to the power input terminal of the grid according to the grid power input command issued by the energy management and optimization module, and at the same time disconnects the discharge circuit of the battery energy storage module, so that the air separation unit module is completely powered by the grid and maintains the air separation unit module to operate continuously within the rated power range.

[0062] During periods when wind and solar power are not subject to curtailment, the energy management and optimization module also implements the following strategies: When the grid electricity price is in the off-peak range, it utilizes off-peak electricity to supplement the battery energy storage module. Specifically, the energy management and optimization module monitors the grid electricity price signal during periods when wind and solar power are not subject to curtailment. When the grid electricity price is lower than the preset off-peak price threshold, it generates an off-peak electricity supplementation command. The power dispatch control unit controls the DC-AC inverter of the battery energy storage module to operate in rectification mode, converting the grid AC power into DC power, and charging the electrochemical energy storage battery pack according to the constant current and constant voltage charging strategy set by the battery management system. When the grid electricity price is in the peak range and the battery energy storage module has sufficient remaining power, it prioritizes using the battery energy storage module to reduce peak electricity consumption. Specifically, the energy management and optimization module monitors the grid price signal during non-curtailment periods. When the grid price is higher than the preset peak price threshold and the state of charge of the battery energy storage module is higher than the preset discharge threshold, a peak discharge command is generated. The power dispatch control unit controls the DC-AC inverter of the battery energy storage module to work in inverter mode, converting the DC power stored in the electrochemical energy storage battery pack into AC power to drive the air separation unit module to operate, while disconnecting the connection with the grid power input terminal.

[0063] In terms of the specific operation of the air separation unit module, the air separation unit module maintains rated operating conditions or slowly changing load conditions under various power supply modes, continuously performing air separation operations. The energy management and optimization module sends load adjustment commands to the variable frequency drive of the multi-stage air compressor unit based on the power supply mode switching signal, enabling the multi-stage air compressor unit to slowly adjust within 95% to 105% of its rated speed to maintain a stable gas-liquid balance between the rising gas and the reflux liquid in the distillation column of the distillation separation unit. The feed air first passes through a self-cleaning air filter to remove dust particles larger than 1 micrometer in diameter, and then enters the three-stage centrifugal compressor unit. Specifically, the first-stage compressor compresses the air to 0.2 to 0.3 MPa, and after being cooled by an interstage cooler, it enters the second-stage compressor and is compressed to 0.6 to 0.8 MPa. After being cooled again by an interstage cooler, it enters the third-stage compressor and is compressed to the set pressure of 0.8 to 1.0 MPa. Compressed air enters the air-cooled tower of the pre-cooling purification unit, where it comes into counter-current contact with circulating cooling water from the cooling tower, cooling to 10-15 degrees Celsius. It then enters the molecular sieve adsorber, where 13X-type molecular sieves adsorb and remove moisture and carbon dioxide from the compressed air, lowering the dew point to below -60 degrees Celsius. The pre-cooled and purified compressed air then enters the main heat exchange unit for further cooling to near its liquefaction temperature, before being sent to the distillation separation unit for cryogenic distillation separation. The cryogenic air enters the lower distillation column from the feed air inlet at the bottom, where rising gas and reflux liquid exchange heat and mass. Nitrogen gas at the top of the lower distillation column rises to the condenser-evaporator, exchanging heat with liquid oxygen at the bottom of the upper distillation column. The nitrogen is condensed into liquid nitrogen and refluxed back to the lower distillation column, while the liquid oxygen is evaporated into oxygen and rises to the upper distillation column, forming a thermo-mass coupling cycle between the lower and upper distillation columns. Nitrogen gas is obtained at the top of the lower distillation column, and oxygen-enriched liquid air is obtained at the bottom. The oxygen-enriched liquid air, after being throttled and depressurized, is fed into the middle section of the upper distillation column, where it undergoes further separation. Nitrogen is obtained at the top of the upper distillation column, oxygen at the bottom, and argon from the side stream. The separated liquid products can be stored in a liquid product storage tank connected to the air separation unit module.

[0064] This embodiment integrates the battery energy storage module and the new energy power generation module into the power supply circuit of the air separation system. By utilizing the coordinated control of the power dispatch control unit and the energy management and optimization module, it achieves efficient utilization of curtailed wind and solar green electricity, avoids the disturbance caused by frequent load changes to the distillation tower operating conditions, significantly improves the operational stability and product purity stability of the air separation unit, and greatly reduces electricity costs.

[0065] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0066] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0067] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0068] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0069] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An air separation system that utilizes curtailed wind and solar power coupled with battery energy storage, characterized in that, include: New energy power generation module; Battery energy storage module; The power dispatch control unit is used to monitor the power output of the new energy power generation module, the state of charge of the battery energy storage module, and the grid electricity price information in real time. The energy management and optimization module is used to execute scheduling strategies based on monitoring data from the power dispatch control unit: when the power output of the new energy generation module is higher than the real-time power demand of the air separation unit module, it is determined to be a period of wind and solar curtailment, and all the green electricity generated by the new energy generation module is prioritized to drive the operation of the air separation unit module, and the redundant energy is stored in the battery energy storage module; when the power output of the new energy generation module is lower than the real-time power demand of the air separation unit module but the state of charge of the battery energy storage module is higher than a preset threshold, the battery energy storage module is controlled to release stored energy to supplement power supply and maintain the continuous operation of the air separation unit module within the rated power range; when the state of charge of the battery energy storage module is lower than the preset threshold and the power output of the new energy generation module is still insufficient, the module switches to grid power supply mode to ensure the continuous operation of the air separation unit module. The air separation unit module is used to maintain rated operation or slowly changing load operation under various power supply modes to continuously perform air separation operations. The air separation unit module includes a raw material air filtration unit, a multi-stage air compressor unit, a pre-cooling purification unit, a main heat exchange unit, and a distillation separation unit. The air separation operation includes: the raw material air is filtered by the raw material air filtration unit and then enters the multi-stage air compressor unit to be compressed to a set pressure. The compressed air is cooled and water and carbon dioxide are removed by the pre-cooling purification unit and then enters the main heat exchange unit for further cooling to near the liquefaction temperature. The low-temperature air is sent to the distillation separation unit for low-temperature distillation separation to obtain nitrogen, oxygen, and argon products, respectively.

2. The system according to claim 1, characterized in that, The power dispatch control unit monitors the power output of the new energy power generation module in real time, including: Power sensors deployed at the grid connection points of wind turbine generators and photovoltaic power generation arrays collect active power data in real time, and transmit the active power data to the data acquisition module of the power dispatch control unit via a communication bus to generate the real-time output curve of the new energy power generation module.

3. The system according to claim 1, characterized in that, The energy management and optimization module executes scheduling strategies based on monitoring data, including: The energy management and optimization module receives the power output of the new energy generation module, the state of charge of the battery energy storage module, and the grid electricity price information transmitted by the power dispatch control unit. Based on the preset priority logic, it determines the current power supply mode and sends the power supply mode switching command to the power electronic switch array of the power dispatch control unit to execute the automatic switching between the new energy green electricity power supply mode, the battery energy storage power supply mode, and the grid power supply mode.

4. The system according to claim 3, characterized in that, The energy management and optimization module determines the current power supply mode based on preset priority logic, including: The energy management and optimization module compares the power output of the new energy power generation module with the real-time power demand of the air separation unit module. When the power output is greater than or equal to the real-time power demand, the module generates the new energy green electricity power supply mode instruction. When the power generation output is less than the real-time power demand and the state of charge of the battery energy storage module is higher than the preset threshold, the battery energy storage power supply mode command is generated. When the power generation output is less than the real-time power demand and the state of charge of the battery energy storage module is lower than the preset threshold, the grid power supply mode command is generated.

5. The system according to claim 1, characterized in that, The period when the power output of the new energy power generation module is higher than the real-time power demand of the air separation unit module is determined to be a period of wind and solar curtailment includes: The energy management and optimization module compares the real-time power output of the new energy power generation module with the rated power limit of the air separation unit module. When the real-time power output exceeds the rated power limit and the excess portion continues to exceed a preset time threshold, it determines that the current period is a wind and solar curtailment period and triggers the redundant energy storage process.

6. The system according to claim 1, characterized in that, The step of storing redundant electrical energy into the battery energy storage module includes: The power dispatch control unit controls the DC-DC converter of the battery energy storage module to convert the redundant green electricity generated by the new energy power generation module into DC electricity that is compatible with the charging voltage of the battery energy storage module, according to the energy storage instructions issued by the energy management and optimization module, and charges the electrochemical energy storage battery pack according to the constant current and constant voltage charging strategy set by the battery management system.

7. The system according to claim 1, characterized in that, The method of releasing stored electrical energy from the battery energy storage module to supplement power supply includes: According to the discharge command issued by the energy management and optimization module, the power dispatch control unit controls the DC-AC inverter of the battery energy storage module to convert the DC power stored in the electrochemical energy storage battery pack into AC power that matches the power supply voltage and frequency of the air separation unit module, and then combines it with the output of the new energy power generation module to jointly drive the operation of the air separation unit module.

8. The system according to claim 1, characterized in that, The grid connection power supply mode includes: According to the power grid input command issued by the energy management and optimization module, the power dispatch control unit closes the grid connection switch connected to the power grid input terminal and disconnects the discharge circuit of the battery energy storage module, so that the air separation unit module is completely powered by the grid and maintains the air separation unit module in continuous operation within the rated power range.

9. The system according to claim 1, characterized in that, The air separation unit module maintains rated operation or slowly changing load operation under various power supply modes, including: The energy management and optimization module sends a load adjustment command to the variable frequency drive of the multi-stage air compressor unit according to the power supply mode switching signal, so that the multi-stage air compressor unit can be gradually adjusted within the set range of rated speed to maintain the stable gas-liquid balance between the rising gas and the reflux liquid in the distillation column of the distillation separation unit.

10. The system according to claim 1, characterized in that, The air separation system also includes a liquid product storage tank connected to the air separation unit module for storing the liquid products produced by the distillation separation unit.

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