Geothermal gradient utilization digital-analog and measurement and control combined control system

Abstract

The invention relates to the technical field of terrestrial heat utilization, and discloses a terrestrial heat gradient utilization digital-analog and measurement and control combined control system which comprises a gradient heat exchange unit, a data acquisition unit, a data processing unit and an execution unit. The cascade heat exchange unit comprises at least two groups of heat exchangers which are arranged in the vacuum heat insulation cavity and form heat exchange runners connected in series and / or in parallel in the heat source flowing direction; the data acquisition unit acquires first temperature information of a heat output end of a heat exchange pipeline and second temperature information of an input end of a heat source output pipeline to construct a temperature detection array; the data processing unit calculates the deviation value between the second temperature information and the user heat load demand to dynamically adjust the heat exchange control strategies of the heat exchange pipelines corresponding to the multiple sets of first temperature information in the operation state till the deviation value is 0; the execution unit executes the heat exchange control strategy to control the proportional valve to adjust the flow speed of the cold source in the heat exchanger and control the first electronic valve to control opening and closing of the heat exchange pipeline, and the dynamic heat load requirements of different scenes are met.

Description

Technical Field

[0001] This invention relates to the field of geothermal utilization technology, specifically to a combined digital simulation and measurement and control system for geothermal cascade utilization. Background Technology

[0002] In the current development and utilization of geothermal resources, the requirements for heat exchange efficiency and temperature control accuracy in scenarios such as geothermal heating and industrial heat use are increasing. However, traditional geothermal heat exchange systems still have the following technical problems that urgently need to be solved: existing systems mostly rely on manual adjustment of valves to control the cold source flow rate or heat exchange area, lacking real-time monitoring and intelligent control mechanisms. On the one hand, monitoring only the total heating temperature cannot locate heat exchange anomalies in individual heat exchange pipes, resulting in lag in regulation; on the other hand, the regulation strategy is singular (such as only increasing or decreasing the cold source flow rate), and cannot dynamically adapt to the deviation between "actual heating temperature and user demand," easily leading to heating temperature fluctuations (the deviation is often > ±2℃), making it difficult to meet the temperature stability requirements of residential heating and precision industrial heat use. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a geothermal cascade utilization digital simulation and measurement and control system to solve the technical problems mentioned in the prior art.

[0004] A geothermal cascade utilization digital simulation and measurement and control system includes: A tiered heat exchange unit includes at least two sets of heat exchangers placed within a vacuum-insulated cavity. The heat source sides of two adjacent or connected sets of heat exchangers are interconnected and form series and / or parallel heat exchange channels along the heat source flow direction. A heat source flows through the heat exchange channels. Each heat exchanger is configured such that it has an internal array of several heat exchange pipes, through which a cold source flows. Each heat exchange pipe and the heat exchange channel form a heat exchange cavity with equal wall thickness. The heat source output ends of all the heat exchange pipes are integrated and connected to the input end of the heat source output pipe. The data acquisition unit is equipped with a first temperature detection sensor at the heat output end of each heat exchange pipe for collecting first temperature information; and a second temperature detection sensor is equipped at the input end of the heat source output pipe for collecting second temperature information; the data acquisition unit constructs a temperature detection array with multiple first temperature detection sensors and second temperature detection sensors to acquire multiple sets of first temperature information and second temperature information in real time. The data processing unit calculates the deviation between the second temperature information and the user's heat load requirement based on multiple sets of first temperature information and second temperature information acquired in real time by the data acquisition unit; and dynamically adjusts the heat exchange control strategy of the heat exchange pipeline corresponding to the multiple sets of first temperature information in operation according to the deviation value until the deviation value is 0. The execution unit is provided with a proportional valve at the cold input end of each heat exchanger and a first electronic valve at the cold input end of each heat exchange pipe; the execution unit executes the heat exchange control strategy of the heat exchange pipe sent by the data processing unit to control the proportional valve to adjust the flow rate of the cold source in the heat exchanger and the first electronic valve to control the opening and closing of the heat exchange pipe.

[0005] Optionally, the heat exchange control strategy is configured as follows: When the calculated deviation value is not 0, the absolute value of the calculated deviation value is used to perform a difference operation with multiple sets of the first temperature information to obtain the temperature regulation parameter of the corresponding heat exchange pipeline. When the temperature regulation parameter of at least one group of the heat exchange pipes is equal to 0 and the calculated deviation value is positive, a first control command is generated to control any one group of the heat exchange pipes in the corresponding heat exchanger to shut down. When the temperature regulation parameter of at least one group of heat exchange pipes is equal to 0 and the calculated deviation value is negative, a second control command is generated to control any one group of heat exchange pipes in the corresponding heat exchanger to open until all heat exchange pipes are in the open state. Then, according to the flow direction of the heat source, the opening degree of the proportional valves of multiple groups of heat exchangers is reduced by a preset unit amount in sequence, and the operation is repeated until the deviation value is non-negative. When the temperature regulation parameters of all the heat exchange pipes are not equal to 0, a third control command is generated to control the heat exchange efficiency of any heat exchange pipe whose first temperature information is closest to the temperature regulation parameter. The third control command is configured to: use the operator sign of the deviation value as a reference and dynamically adjust the flow rate of the cold source in the heat exchange pipe according to its change value; wherein, if the operator sign of the deviation value is negative, the opening degree of the proportional valve at the cold source input end of the corresponding heat exchanger is reduced by a preset unit amount until the proportional valve is closed; if the operator sign of the deviation value is positive, the opening degree of the proportional valve at the cold source input end of the corresponding heat exchanger is increased by a preset unit amount until the proportional valve is fully open.

[0006] Optionally, the cascade heat exchange unit includes a heat-insulating shell with a hollow interior. A vacuum adsorption port is provided through the inner wall of the heat-insulating shell. The vacuum adsorption port is connected to the air inlet of a vacuum generator through a pipe. The vacuum generator is used to extract the air from inside the heat-insulating shell to achieve a preset vacuum level and form a vacuum heat-insulating cavity.

[0007] Optionally, a vacuum detector is installed inside the heat insulation shell. The vacuum detector is connected to the vacuum generator, and the vacuum generator automatically starts and stops according to the vacuum information detected by the vacuum detector in real time.

[0008] Optionally, a heat-conducting insulation layer is provided between the opposing surfaces of two adjacent heat exchangers and / or between the heat exchanger and the sidewall of the vacuum insulated cavity; The thermal conductivity of the heat-conducting insulation layer is ≤0.1-0.2W / m·K.

[0009] Optionally, the heat-conducting insulation layer includes square timber and a plurality of mounting bases that can be detachably installed on the square timber, and two adjacent mounting bases do not contact each other; The mounting base is connected to the outer periphery of the heat exchanger and / or the sidewall of the vacuum-insulated cavity.

[0010] Optionally, each heat exchanger is provided with at least two sets of heat exchange pipes, and the cold source input ends of all the heat exchange pipes in the same heat exchanger are connected in parallel to a cold source input pipe, and the heat source output ends of all the heat exchange pipes in the same heat exchanger are connected in parallel to a heat source output pipe. The cold input end of the cold source input pipe and the hot output end of the heat source output pipe pass through the shell of the heat exchanger and the vacuum insulation cavity in sequence and extend to the outside of the cascade heat exchange unit, and are connected to the corresponding cold source and user load end in a distributed or centralized manner. The proportional valve is installed on the cold source input pipe.

[0011] Optionally, when the heat output end of the heat source output pipe is centrally connected to the user load end, wherein, A first check valve is installed at the heat output end of the heat exchange pipe. A second check valve is installed on the heat source output pipe along the fluid flow direction.

[0012] Optionally, n-1 connecting pipes are arranged along an S-shaped trajectory between the heat source sides of the multiple heat exchangers. The two ends of the connecting pipes respectively penetrate and connect the inner walls of two adjacent heat exchangers, thereby forming a series heat exchange channel along the heat source flow direction; where n is the number of heat exchangers, and a switching valve is installed on the connecting pipe. Each heat exchanger is provided with a heating connector and a return connector on its heat source side. All heating connectors pass through the heat exchanger and the vacuum insulated cavity in sequence and are connected to the heat source input pipe. The heat source input pipe is connected to the extraction end of the geothermal well. A second electronic valve is installed at each heating connector. All return connectors pass through the heat exchanger and the vacuum insulated cavity in sequence and are connected to the cold source output pipe. The cold source output pipe is connected to the return end of the reinjection well. A third electronic valve is installed at each return connector.

[0013] Optionally, the outer periphery array of the heat exchange pipe is provided with multiple heat exchange fins; Multiple heat exchange fins are arranged non-linearly along the axial direction of the heat exchange pipe to form several interconnected or parallel non-linear heat exchange cavities within the heat exchange cavity. Alternatively, multiple heat exchange fins are evenly arranged along the axial direction of the heat exchange pipe to divide the heat exchange cavity into multiple annular liquid storage tanks arranged side by side, and multiple liquid passage holes are opened on the heat exchange fins along the fluid flow direction to connect two adjacent annular liquid storage tanks.

[0014] The beneficial effects that this invention can produce include: 1. The geothermal cascade utilization digital simulation and measurement and control system provided by this invention uses a first temperature sensor (heat output end of a single heat exchange pipe) to locate local heat exchange anomalies and a second temperature sensor (input end of a heat source output pipe) to monitor the overall heat exchange status, thus constructing a dual-dimensional temperature monitoring array of "single pipe - total system" to provide accurate data support for geothermal energy output regulation. Simultaneously, based on a deviation-driven dynamic adjustment strategy, it can flexibly select control methods such as "closing / opening a single heat exchange pipe" and "adjusting the opening degree of a proportional valve" according to the deviation between the "total heating temperature and user demand," enabling the system temperature control accuracy to reach ±0.5℃. This effectively solves the problems of lag and large fluctuations in traditional systems, meeting the dynamic heat load requirements of different scenarios.

[0015] 2. The tiered heat exchange unit of this invention adopts a dual insulation design of "vacuum insulated cavity + heat conduction insulation layer". This design ensures that the vacuum cavity maintains a preset vacuum level (<10Pa) through the linkage between the vacuum generator and the vacuum degree detector, thus blocking air heat conduction. Simultaneously, the heat conduction insulation layer (thermal conductivity ≤0.1-0.2W / m・K) avoids solid thermal bridging through a "square timber + independent mounting base" structure. This dual design reduces heat loss by more than 40%. Furthermore, it is equipped with a series / parallel switchable tiered heat exchange channel. The series mode is suitable for medium-high temperature geothermal (60-90℃) requirements, enabling continuous tiered heat exchange for industrial heating or residential heating. The parallel mode is suitable for low temperature geothermal (40-60℃) requirements, allowing flexible operation of individual heat exchangers. The overall system energy utilization rate is increased to over 85%, significantly reducing geothermal resource waste.

[0016] 3. The heat source side flow channel of this invention supports modular switching. Through a combination of connecting pipes (equipped with switching valves) and second / third electronic valves, it can quickly switch between series and parallel flow channels, adapting to geothermal resources with different temperatures and flow rates from 40-90℃. This eliminates the need for large-scale modifications to the system structure, significantly improving versatility. Simultaneously, the heat exchange pipes adopt a parallel integrated design, connecting multiple sets of heat exchange pipes within a single heat exchanger to the cold source input / heat source output pipes. Combined with a detachable heat conduction insulation layer base, it is easy to add or remove heat exchange pipes according to heat load requirements, further enhancing the system's adaptability to various operating conditions.

[0017] 4. This application features a multi-check valve protection structure, facilitating maintenance and repair of individual heat exchangers during system operation while ensuring uninterrupted system operation. The first check valve (at the heat output end of a single heat exchange pipe) prevents localized fluid backflow, while the second check valve (at the main heat source output pipe) prevents system-wide backflow, ensuring heat exchange uniformity and stability, as well as personnel safety during maintenance. Simultaneously, intelligent vacuum pressure maintenance is employed, using a vacuum detector to monitor the cavity vacuum level in real time. When the vacuum level falls below a preset value, the vacuum generator automatically activates to replenish the vacuum, preventing insulation failure. Furthermore, real-time monitoring by multiple sensors (temperature and vacuum level) provides timely warnings of pipe blockages, valve malfunctions, and other faults. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the cascade heat exchange unit of the present invention; Figure 2 In this invention Figure 1 Rear view; Figure 3 In this invention Figure 1 Internal structure diagram; Figure 4 This is a system architecture block diagram of the present invention; Figure 5 In this invention Figure 3 A schematic diagram of the structure of the heat-conducting insulation layer; Figure 6 In this invention Figure 3 Schematic diagram of the cross-section of the heat exchanger Figure 1 ; Figure 7 In this invention Figure 3 Schematic diagram of the cross-section of the heat exchanger Figure 2 ; Figure 8 In this invention Figure 3 Schematic diagram of heat exchange pipes Figure 1 ; Figure 9 In this invention Figure 3 Schematic diagram of heat exchange pipes Figure 2 ; In the diagram: 1. Cascade heat exchange unit; 101. Insulated outer shell; 1011. Vacuum insulated cavity; 102. Heat exchanger; 1021. Heat exchange channel; 1022. Heat exchange cavity; 103. Heat exchange pipe; 104. Inspection window; 105. Connecting pipe; 2. Data acquisition unit; 201. First temperature sensor; 202. Second temperature sensor; 3. Data processing unit; 301. Data input module; 302. Deviation calculation module; 303. Instruction generation module; 304. Instruction distribution module; 305. Linkage early warning module; 4. Execution unit; 01. Proportional valve; 402. First electronic valve; 403. Second electronic valve; 404. Third electronic valve; 405. First check valve; 406. Second check valve; 5. Vacuum detector; 6. Vacuum generator; 7. Heat conduction insulation layer; 701. Timber; 702. Mounting base; 8. Cold source input pipe; 9. Heat source output pipe; 10. Heating connector; 11. Heat source input pipe; 12. Return connector; 13. Cold source output pipe; 14. Heat exchange fins; 15. Nonlinear heat exchange chamber; 16. Annular liquid storage tank; 17. Liquid passage hole; 18. Early warning unit. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only 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.

[0020] Please see Figure 1-4As shown, this invention provides a geothermal cascade control system combining digital modeling and measurement and control, including a cascade heat exchange unit 1, a data acquisition unit 2, a data processing unit 3, and an execution unit 4. The cascade heat exchange unit 1 includes at least two sets of heat exchangers 102 placed in a vacuum-insulated cavity 1011, and the heat source sides of two adjacent or connected sets of heat exchangers 102 are interconnected, forming a series and / or parallel heat exchange channel 1021 along the heat source flow direction, through which a heat source flows. The heat exchangers 102 are configured such that: a plurality of heat exchange pipes 103 are arrayed inside, through which a cold source flows; and each heat exchange pipe 103 and the heat exchange channel 1021 form a heat exchange cavity 1022 of equal wall thickness, and all heat exchange pipes 103... The heat source output end is integrated and connected to the input end of the heat source output pipe 9; the data acquisition unit 2 is equipped with a first temperature detection sensor 201 at the heat output end of each heat exchange pipe 103 for collecting first temperature information; and a second temperature detection sensor 202 is equipped at the input end of the heat source output pipe 9 for collecting second temperature information; the data acquisition unit 2 constructs a temperature detection array with multiple first temperature detection sensors 201 and second temperature detection sensors 202 to acquire multiple sets of first temperature information and second temperature information in real time; thereby, by using the first temperature sensor to locate local heat exchange anomalies and the second temperature sensor to monitor the overall heat exchange status, a "single pipe-to-system" dual-dimensional temperature monitoring array is constructed to provide accurate data support for the output regulation of geothermal energy. The data processing unit 3 calculates the deviation between the second temperature information and the user's heat load requirement based on the multiple sets of first temperature information and second temperature information acquired in real time by the data acquisition unit 2; and dynamically adjusts the heat exchange control strategy of the heat exchange pipe 103 corresponding to the multiple sets of first temperature information in operation according to the deviation value until the deviation value is 0; the execution unit 4 is provided with a proportional valve 401 at the cold input end of each heat exchanger 102 and a first electronic valve 402 at the cold input end of each heat exchange pipe 103; the execution unit 4 executes the heat exchange control strategy of the heat exchange pipe 103 sent by the data processing unit 3 to control the proportional valve 401 to adjust the flow rate of the cold source in the heat exchanger 102 and the first electronic valve 402 to control the opening and closing of the heat exchange pipe 103. Therefore, the dynamic adjustment strategy driven by the deviation value can flexibly select the control methods such as "closing / opening a single heat exchange pipe 103" and "adjusting the opening degree of the proportional valve 401" according to the deviation value between "total heating temperature and user demand". This makes the system temperature control accuracy reach ±0.5℃, effectively solving the problems of lag and large fluctuation in traditional system adjustment, and meeting the dynamic heat load requirements of different scenarios.

[0021] Furthermore, the heat exchange control strategy is configured as follows: When the calculated deviation value is not 0, the absolute value of the calculated deviation value is used to perform difference calculation with multiple sets of first temperature information to obtain the temperature regulation parameter of the corresponding heat exchange pipe 103. When the temperature regulation parameter of at least one set of heat exchange pipes 103 is equal to 0 and the calculated deviation value is positive, a first control command is generated to control any set of heat exchange pipes 103 in the corresponding heat exchanger 102 to close. When the temperature regulation parameter of at least one set of heat exchange pipes 103 is equal to 0 and the calculated deviation value is negative, a second control command is generated to control any set of heat exchange pipes 103 in the corresponding heat exchanger 102 to open until all heat exchange pipes 103 are in the open state. Then, according to the flow direction of the heat source, the opening degree of the proportional valve 401 of multiple sets of heat exchangers 102 is reduced by a preset unit amount, and the operation is repeated until the deviation value is non-negative. When the temperature regulation parameters of all heat exchange pipes 103 are not equal to 0, a third control command is generated to control the heat exchange efficiency of any heat exchange pipe 103 whose first temperature information is closest to the temperature regulation parameter. The third control command is configured to dynamically adjust the flow rate of the cold source in the heat exchange pipe 103 based on the change value of the deviation value operator sign as a reference. Specifically, if the deviation value operator sign is negative, the opening degree of the proportional valve 401 at the cold source input end of the corresponding heat exchanger 102 is reduced by a preset unit amount until the proportional valve 401 is in the closed state; if the deviation value operator sign is positive, the opening degree of the proportional valve 401 at the cold source input end of the corresponding heat exchanger 102 is increased by a preset unit amount until the proportional valve 401 is in the fully open state. This system, through the configuration of real-time monitoring and intelligent control mechanisms, can effectively solve the timeliness problem of traditional manual valve control of heat exchange performance and meet the requirements for temperature stability and diversified temperature output for residential heating, precision industrial heating, etc.

[0022] Furthermore, such as Figure 3As shown, the cascade heat exchange unit 1 includes a heat-insulating shell 101. The heat-insulating shell 101 has a hollow structure inside. A vacuum adsorption port is provided through the inner wall of the heat-insulating shell 101. The vacuum adsorption port is connected to the air inlet of the vacuum generator 6 through a pipe. The vacuum generator 6 is used to extract the air inside the heat-insulating shell 101 so that the interior reaches a preset vacuum degree to form a vacuum heat-insulating cavity 1011. Specifically, a vacuum level detector 5 is installed inside the heat insulation shell 101. The vacuum level detector 5 is connected to a vacuum generator 6. The vacuum generator 6 automatically starts and stops according to the vacuum level information detected in real time by the vacuum level detector 5. Thus, the vacuum level of the cavity is monitored in real time by the vacuum level detector 5. When it is lower than the preset value, the vacuum generator 6 is automatically started to replenish the vacuum, preventing heat insulation failure. At the same time, multiple sensors (temperature, vacuum level) are coupled to monitor the system operation status in real time. These sensors can be connected to the early warning unit 18 (such as an alarm and embedded control algorithm) to promptly warn of preset fault information such as pipe blockage and valve failure when the sensor detection value exceeds the threshold range, thereby improving the timeliness of system maintenance and reducing the system failure rate. In the above, as shown... Figure 1 As shown, in order to facilitate the replacement and maintenance of the components inside the heat insulation shell 101, inspection windows 104 are detachably installed on its outer periphery and on one side of the heat exchanger 102, and elastic sealing strips are provided at the connection to ensure the sealing of the connection.

[0023] Furthermore, such as Figure 3 As shown, a heat-conducting insulation layer 7 is provided between the opposing surfaces of two adjacent heat exchangers 102 and / or between the heat exchanger 102 and the sidewall of the vacuum-insulated cavity 1011; the thermal conductivity of the heat-conducting insulation layer 7 is ≤0.1-0.2W / m·K, effectively avoiding the solid thermal bridge effect, reducing the heat loss of the heat exchanger 102, and ensuring the consistency of heat exchange efficiency among multiple sets of heat exchangers 102. Specifically, as... Figure 5 As shown, the heat conduction insulation layer 7 includes a square timber 701 and several mounting bases 702 that can be detachably mounted on the square timber 701, and two adjacent mounting bases 702 do not contact each other; the mounting bases 702 are detachably connected to the outer periphery of the heat exchanger 102 and / or the side wall of the vacuum insulation cavity 1011 by bolts, which makes it easy to add or remove heat exchangers 102 or heat exchange pipes 103 located inside them according to heat load requirements, further enhancing the system's adaptability to operating conditions.

[0024] Furthermore, such as Figure 3As shown, each heat exchanger 102 is equipped with at least two sets of heat exchange pipes 103. The cold source input ends of all heat exchange pipes 103 within the same heat exchanger 102 are connected in parallel to a single cold source input pipe 8, and the heat source output ends of all heat exchange pipes 103 within the same heat exchanger 102 are connected in parallel to a single heat source output pipe 9. The cold input end of the cold source input pipe 8 and the heat output end of the heat source output pipe 9 pass through the shell of the heat exchanger 102 and the vacuum insulation cavity 1011, respectively, and extend to the outside of the cascade heat exchange unit 1. They are connected to the corresponding cold source and user load using a distributed or centralized connection. When the connection is distributed to the corresponding user load, a heating pipeline corresponding one-to-one with the number of heat exchangers 102 can be formed, facilitating simultaneous heating of user loads in multiple areas (not shown in the figure). When the connection is centralized to the corresponding user load, the final heating temperature of the heat source output pipe 9 can be adjusted according to the heating demand, thereby meeting different application scenarios, such as... Figure 1 and Figure 3 As shown. Specifically, the cold source (such as the water pump built into the storage tank that supplies cold to the system) can be selected to be connected in a distributed or centralized manner through multiple cold source input pipes 8, depending on the control requirements. For example... Figure 2 and Figure 3 As shown, the proportional valve 401 is installed on the cold source input pipe 8 to cooperate with the first electronic valve 402 to regulate the overall cold source input flow rate and velocity of the single heat exchanger 102.

[0025] Furthermore, such as Figure 3 As shown, when the heat output end of the heat source output pipe 9 is centrally connected to the user load, a first check valve 405 is installed at the heat output end of the heat exchange pipe 103 to prevent local fluid backflow; a second check valve 406 is installed on the heat source output pipe 9 along the fluid flow direction to prevent system-level backflow. This multi-check valve protection structure facilitates maintenance of a single heat exchanger 102 during system operation, ensuring uninterrupted system operation; it also prevents pressure differences between adjacent heat exchangers 102 due to different flow velocities, thus avoiding fluid backflow in the heat exchange pipe 103 and resulting in sudden local temperature changes, ensuring heat exchange uniformity and stability, as well as personnel safety during maintenance.

[0026] Furthermore, such as Figure 3As shown, n-1 connecting pipes 105 are arranged along an S-shaped trajectory between the heat source sides of multiple heat exchangers 102. The two ends of the connecting pipes 105 respectively penetrate and connect the inner walls of two adjacent heat exchangers 102, thereby forming a series heat exchange channel 1021 along the heat source flow direction; where n is the number of heat exchangers 102, and a switch valve is installed on the connecting pipe 105; each heat exchanger 102 is provided with a heating connector 10 and a return connector 12 on its heat source side; all heating connectors 10 sequentially penetrate the heat exchanger 102 and the vacuum insulation cavity 1011 and connect to the heat source input pipe 11, which connects to the mining end of the geothermal well, and a second electronic valve 403 is installed at the heating connector 10; all return connectors 12 sequentially penetrate the heat exchanger 102 and the vacuum insulation cavity 1011 and connect to the cold source output pipe 13, which connects to the return end of the reinjection well, and a third electronic valve 404 is installed at the return connector 12. This allows the heat source side flow channel of the system to support modular switching. Through the combination of connecting pipe 105 (equipped with a switching valve) and second / third electronic valve, it can quickly switch between series and parallel flow channels, adapting to geothermal resources with different temperatures and flow rates from 40-90℃. This eliminates the need for large-scale modifications to the system structure and significantly improves its versatility.

[0027] Furthermore, such as Figure 8 and Figure 9 As shown, the outer periphery of the heat exchange pipe 103 is arrayed with multiple heat exchange fins 14; the multiple heat exchange fins 14 are arranged non-linearly along the axial direction of the heat exchange pipe 103 to form several interconnected or parallel non-linear heat exchange cavities 15 within the heat exchange cavity 1022; or, as shown Figure 6 and Figure 7 As shown, multiple heat exchange fins 14 are evenly arranged along the axial direction of the heat exchange pipe 103 to divide the heat exchange cavity 1022 into multiple annular liquid storage tanks 16 arranged side by side. Multiple liquid passage holes 17 are opened on the heat exchange fins 14 along the fluid flow direction to connect two adjacent annular liquid storage tanks 16, thereby increasing the heat exchange contact area and improving the heat exchange efficiency of the heat exchange pipe 103.

[0028] In the above, such as Figure 4As shown, the data processing unit 3 includes a data input module 301, a deviation calculation module 302, an instruction generation module 303, an instruction distribution module 304, and a linkage early warning module 305. The data input module 301 is configured to receive multi-dimensional monitoring data transmitted from the data acquisition unit 2, and preprocess the multi-dimensional monitoring data to ensure data validity and provide a reliable basis for subsequent calculations. The deviation calculation module 302 calculates the deviation value and temperature regulation parameters based on the user's heat load requirements and the real-time monitored multi-dimensional data. It then uses the deviation value to determine the overall heating status and the temperature regulation parameters to locate local control objects. All calculated temperature regulation parameters are associated one-to-one with the corresponding heat exchange pipes 103 to obtain a pipe-regulation parameter lookup table, which is then pushed to the instruction generation module 303. The instruction generation module 303, based on the calculated deviation value and temperature regulation parameters, traverses the pipe-regulation parameter lookup table and generates a first control instruction, a second control instruction, and a third control instruction according to preset logic. The instruction distribution module 304 includes an instruction encoding submodule, a communication sending submodule, and an instruction log submodule. The instruction encoding submodule is configured to perform instruction format conversion and checksum generation. The communication sending submodule is configured to establish a hardware connection with the execution unit 4 and send the first, second, and third control instructions to the execution unit 4 via the communication link. The instruction log submodule is configured to store instruction execution records. The linkage and early warning module 305 includes a fault determination submodule, an early warning linkage submodule, and an emergency control submodule. The fault determination submodule is configured to have a built-in fault threshold database and compare multi-dimensional monitoring data in real time to determine if it falls within the fault threshold range. The early warning linkage submodule is configured to connect to the early warning unit 18 (indicator light, buzzer) via a remote communication module to generate an early warning signal and control the early warning unit 18 to issue an early warning message when the fault determination submodule detects that the multi-dimensional monitoring data exceeds the fault threshold range. The emergency control submodule is configured to generate an emergency instruction simultaneously based on a preset fault emergency strategy library when the early warning linkage submodule generates an early warning signal. The emergency instruction is set to switch to the backup heat exchanger 102 or control the system to shut down. This allows for the identification of system faults based on multi-dimensional monitoring data, and the linkage of early warning unit 18 with emergency control strategies to prevent the faults from escalating, while also supporting system maintenance needs.

[0029] Specifically, the multi-dimensional monitoring data includes temperature data (first temperature information, second temperature information), auxiliary data (cavity vacuum level data), pipeline pressure data, and cold / heat source flow rate data, etc. Preprocessing methods for multi-dimensional monitoring data include: Data cleaning: Filtering outliers (such as out-of-range data caused by sensor malfunction) and removing duplicate data; Data synchronization: unify the timestamps of different sensors to avoid calculation errors caused by differences in data acquisition time. Data caching: A circular buffer is used to temporarily store real-time data and push valid data to the deviation calculation module at a preset frequency.

[0030] Specifically, the method for calculating the deviation value is set as follows: ΔT=T 总 -T 需 ; Where ΔT is the deviation value, T 总 For the second temperature information, T 需 The temperature is the user's heat load requirement. The criteria for determining the deviation value are set as follows: when ΔT > 0, the heating is excessive; when ΔT < 0, the heating is insufficient; when ΔT = 0, the heating requirement is met. The calculation frequency is consistent with the data input layer push frequency to achieve dynamic data updates, which can be set to 1 time / second.

[0031] Specifically, the calculation method for the temperature regulation parameters is set as follows: ΔT i =|ΔT|-T i ; Where, ΔT i T is a temperature regulation parameter. i For the first temperature information of the i-th heat exchange pipe 103, i 1, 2, ..., n.

[0032] Specifically, the method by which the instruction generation module generates the first control instruction, the second control instruction, and the third control instruction based on the calculated deviation value and temperature regulation parameters and according to preset logic includes: wherein the instruction generation module traverses the pipeline-regulation parameter lookup table; If there exists at least one ΔT i If ΔT = 0, it is determined that the output temperature of part of the heat exchange pipe 103 needs to be adjusted; at this time, when ΔT > 0, a first control command is generated to specify a set of ΔT. i The first electronic valve 402 corresponding to heat exchange pipe number 103 with a value of 0 is closed; when ΔT < 0, a second control command is generated, first specifying a set of ΔT. i "The first electronic valve 402 corresponding to the heat exchange pipe number 103 with =0 is opened"; if it is detected that the first electronic valve 402 of all heat exchange pipes 103 is fully open, then according to the heat source flow direction (such as heat exchanger 1→heat exchanger 2→…→heat exchanger n), the opening degree of the proportional valve 401 of the corresponding heat exchanger 102 is controlled to decrease by a preset unit amount (preset unit amount: such as 5% / time), and the cycle continues until ΔT≥0. If all ΔT i If the value is not equal to 0, then it is determined that the output temperature of all heat exchange pipes 103 needs to be adjusted. In this case, the first temperature information T is selected. i Closest to ΔT iThe heat exchange pipe 103, through calculation |T i -ΔT i The minimum value of | is determined; then a third control command is generated to adjust the proportional valve 401 according to the sign of ΔT; specifically, when ΔT < 0, the third control command is configured to reduce the opening degree of the proportional valve 401 of the heat exchanger 102 to which the heat exchange pipe 103 belongs (5% / time) until the proportional valve 401 is fully closed; when ΔT > 0, the third control command is configured to increase the opening degree of the proportional valve 401 of the heat exchanger 102 to which the heat exchange pipe 103 belongs (5% / time) until the proportional valve 401 is fully open.

[0033] It should be noted that if ΔT does not approach 0 after three consecutive adjustments (e.g., the absolute value of ΔT is still > 0.3℃), the adjustment target will be automatically switched to the next set of ΔT values. i The closest heat exchange pipe 103 is used to avoid the accumulation of deviations caused by the failure of the control of a single heat exchange pipe 103.

Claims

1. A geothermal cascade utilization digital simulation and measurement and control system, characterized in that, include: A cascade heat exchange unit (1) includes at least two sets of heat exchangers (102) placed in a vacuum-insulated cavity (1011), and the heat source sides of two adjacent or connected sets of heat exchangers (102) are interconnected and form a series and / or parallel heat exchange channel (1021) along the heat source flow direction, through which a heat source flows; the heat exchanger (102) is configured such that: a plurality of heat exchange pipes (103) are arranged in an array inside, through which a cold source flows; and each heat exchange pipe (103) and the heat exchange channel (1021) form a heat exchange cavity (1022) with equal wall thickness, and the heat source output ends of all the heat exchange pipes (103) are integrated and connected to the input end of the heat source output pipe (9); The data acquisition unit (2) is provided with a first temperature detection sensor (201) at the heat output end of each heat exchange pipe (103) for collecting first temperature information; and a second temperature detection sensor (202) is provided at the input end of the heat source output pipe (9) for collecting second temperature information; the data acquisition unit (2) constructs a temperature detection array with multiple first temperature detection sensors (201) and second temperature detection sensors (202) to acquire multiple sets of first temperature information and second temperature information in real time; The data processing unit (3) calculates the deviation between the second temperature information and the user's heat load requirement based on the multiple sets of first temperature information and second temperature information obtained in real time by the data acquisition unit (2); and dynamically adjusts the heat exchange control strategy of the heat exchange pipeline (103) corresponding to the multiple sets of first temperature information in operation according to the deviation value until the deviation value is 0. The execution unit (4) is provided with a proportional valve (401) at the cold input end of each heat exchanger (102) and a first electronic valve (402) at the cold input end of each heat exchange pipe (103); the execution unit (4) executes the heat exchange control strategy of the heat exchange pipe (103) sent by the data processing unit (3) to control the proportional valve (401) to adjust the flow rate of the cold source in the heat exchanger (102) and the first electronic valve (402) to control the opening and closing of the heat exchange pipe (103).

2. The geothermal cascade utilization digital simulation and measurement and control system according to claim 1, characterized in that, The heat exchange control strategy is configured as follows: When the calculated deviation value is not 0, the absolute value of the calculated deviation value is used to perform a difference operation with multiple sets of the first temperature information to obtain the temperature regulation parameter of the corresponding heat exchange pipe (103); When the temperature regulation parameter of at least one set of heat exchange pipes (103) is equal to 0 and the calculated deviation value is positive, a first control command is generated to control any one set of heat exchange pipes (103) in the corresponding heat exchanger (102) to close. When the temperature regulation parameter of at least one set of heat exchange pipes (103) is equal to 0 and the calculated deviation value is negative, a second control command is generated to control any one set of heat exchange pipes (103) in the corresponding heat exchanger (102) to open until all heat exchange pipes (103) are in the open state. Then, according to the flow direction of the heat source, the opening degree of the proportional valves (401) of multiple sets of heat exchangers (102) is reduced by a preset unit amount, and the operation is repeated until the deviation value is non-negative. When the temperature regulation parameters of all the heat exchange pipes (103) are not equal to 0, a third control command is generated to control the heat exchange efficiency of any heat exchange pipe (103) whose first temperature information is closest to the temperature regulation parameter. The third control command is configured to: use the operator sign of the deviation value as a reference and dynamically adjust the flow rate of the cold source in the heat exchange pipe (103) according to its change value. Wherein, if the operator sign of the deviation value is negative, the opening degree of the proportional valve (401) at the cold source input end of the corresponding heat exchanger (102) is reduced by a preset unit amount until the proportional valve (401) is in the closed state. If the operator sign of the deviation value is positive, the opening degree of the proportional valve (401) at the cold source input end of the corresponding heat exchanger (102) is increased by a preset unit amount until the proportional valve (401) is in the fully open state.

3. The geothermal cascade utilization digital simulation and measurement and control system according to claim 1, characterized in that, The cascade heat exchange unit (1) includes a heat-insulating shell (101). The heat-insulating shell (101) has a hollow structure inside. A vacuum adsorption port is provided through the inner wall of the heat-insulating shell (101). The vacuum adsorption port is connected to the air inlet of a vacuum generator (6) through a pipe. The vacuum generator (6) is used to extract the air inside the heat-insulating shell (101) so that the interior reaches a preset vacuum degree to form a vacuum heat-insulating cavity (1011).

4. The geothermal cascade utilization digital simulation and measurement and control system according to claim 3, characterized in that, The heat insulation shell (101) is equipped with a vacuum detector (5), which is connected to the vacuum generator (6). The vacuum generator (6) automatically starts and stops according to the vacuum information detected in real time by the vacuum detector (5).

5. A geothermal cascade utilization digital simulation and measurement and control system according to claim 1, characterized in that, A heat-conducting insulation layer (7) is provided between the opposite surfaces of two adjacent heat exchangers (102) and / or between the heat exchanger (102) and the sidewall of the vacuum insulation cavity (1011). The thermal conductivity of the heat-conducting insulation layer (7) is ≤0.1-0.2W / m·K.

6. A geothermal cascade utilization digital simulation and measurement and control system according to claim 5, characterized in that, The heat conduction insulation layer (7) includes a square timber (701) and a plurality of mounting bases (702) that can be detachably installed on the square timber (701), and there is no contact between two adjacent mounting bases (702); The mounting base (702) is connected to the outer periphery of the heat exchanger (102) and / or the side wall of the vacuum insulated cavity (1011).

7. A geothermal cascade utilization digital simulation and measurement and control system according to claim 1, characterized in that, Each heat exchanger (102) is provided with at least two sets of heat exchange pipes (103), and the cold source input ends of all the heat exchange pipes (103) located in the same heat exchanger (102) are connected in parallel to a cold source input pipe (8), and the heat source output ends of all the heat exchange pipes (103) located in the same heat exchanger (102) are connected in parallel to a heat source output pipe (9). The cold input end of the cold source input pipe (8) and the hot output end of the heat source output pipe (9) pass through the shell of the heat exchanger (102) and the vacuum insulation cavity (1011) in sequence and extend to the outside of the cascade heat exchange unit (1), and are connected to the corresponding cold source and user load end in a distributed or centralized manner. The proportional valve (401) is installed on the cold source input pipe (8).

8. A geothermal cascade utilization digital simulation and measurement and control system according to claim 7, characterized in that, When the heat output end of the heat source output pipe (9) is connected to the user load end in a centralized manner, wherein, A first check valve (405) is installed at the heat output end of the heat exchange pipe (103). A second check valve (406) is installed on the heat source output pipe (9) along the fluid flow direction.

9. A geothermal cascade utilization digital simulation and measurement and control system according to claim 1, characterized in that, n-1 connecting pipes (105) are arranged along an S-shaped trajectory between the heat source sides of the multiple heat exchangers (102). The two ends of the connecting pipes (105) respectively penetrate and connect the inner walls of two adjacent heat exchangers (102), thereby forming a series heat exchange channel (1021) along the heat source flow direction; where n is the number of heat exchangers (102), and a switching valve is installed on the connecting pipes (105); Each heat exchanger (102) is provided with a heat supply connector (10) and a return connector (12) on the heat source side; all the heat supply connectors (10) pass through the heat exchanger (102) and the vacuum insulation cavity (1011) in sequence and are connected to the heat source input pipe (11), the heat source input pipe (11) is connected to the mining end of the geothermal well, and a second electronic valve (403) is installed at the heat supply connector (10); all the return connectors (12) pass through the heat exchanger (102) and the vacuum insulation cavity (1011) in sequence and are connected to the cold source output pipe (13), the cold source output pipe (13) is connected to the return end of the reinjection well, and a third electronic valve (404) is installed at the return connector (12).

10. A geothermal cascade utilization digital simulation and measurement and control system according to claim 1, characterized in that, The outer periphery array of the heat exchange pipe (103) is provided with multiple heat exchange fins (14). Multiple heat exchange fins (14) are arranged non-linearly along the axial direction of the heat exchange pipe (103) to form several interconnected or parallel non-linear heat exchange cavities (15) within the heat exchange cavity (1022). Alternatively, multiple heat exchange fins (14) are evenly arranged along the axial direction of the heat exchange pipe (103) to divide the heat exchange cavity (1022) into multiple annular liquid storage tanks (16) arranged side by side. Multiple liquid passage holes (17) are opened on the heat exchange fins (14) along the fluid flow direction to connect two adjacent annular liquid storage tanks (16).

Images