Vein radiofrequency ablation system based on parallel thermocouple temperature measurement

Abstract

The invention discloses a vein radiofrequency ablation system based on parallel thermocouple temperature measurement, and relates to the field of medical instruments, the vein radiofrequency ablation system comprises a host control module, a temperature signal transmission module, a thermocouple temperature measurement module, a radiofrequency energy generation module and a catheter heating module, the thermocouple temperature measurement module at least comprises two parallel thermocouples; the host control module is used for fusing the temperature data of the plurality of temperature measuring points and calculating an average temperature, performing abnormal judgment on the average temperature according to a temperature abnormity automatic power-off control strategy, and dynamically triggering a radio frequency energy closing instruction; on the premise of not changing the original size and structure of the catheter and the operation method of a doctor, in a heating unit with a finite length of the catheter, real-time monitoring of local temperature distribution is realized and temperature abnormity is judged by adopting a multi-point parallel temperature measurement scheme, so that when the temperature of a local temperature measurement point is abnormally increased, radio frequency energy output is quickly closed, and the heating efficiency is improved. Further temperature rise is avoided, and adverse events such as tube burning or blood tube burning are prevented.

Description

Technical Field

[0001] The present invention belongs to the field of medical devices, and in particular relates to a venous radiofrequency ablation system based on parallel thermocouple temperature measurement. Background Art

[0002] In recent years, radiofrequency ablation (RFA) has been widely used for great saphenous vein closure due to its minimal invasiveness, rapid recovery, and low recurrence rate. Conventional RF ablation catheters of commonly used lengths feature a heating element with a single temperature sensor positioned within the element. The heating element actively heats and transfers heat energy to the vessel wall in close contact, causing denaturation and contraction of vascular wall proteins and achieving vascular closure. However, clinical application has revealed that the key to this technology lies in the complete and uniform conformation of the ablation catheter's heating element to the vessel wall. During actual procedures, due to the complex structure of blood vessels (such as excessive tortuosity, localized hyperplasia, and thrombosis) and the structural and dimensional limitations of the catheter's heating element, poor contact between the catheter and the vessel wall is common. This leads to uneven heat transfer, rapid localized temperature increases, and even medical accidents such as catheter and vessel burns. Public FDA information and adverse event reports from companies like Medtronic indicate that incidents caused by catheter burns are not uncommon, and similar issues have also been observed in competing products. Although theoretically adding temperature measurement points can accurately grasp the temperature distribution at various locations, since the current ablation catheter contains an outermost insulating film, a ring-wound heating wire, an internal support tube, a guidewire cavity, and built-in radio frequency wires, temperature measurement wires, etc., expanding more temperature sensors and additional wiring solutions within a limited space is not only restricted by physical size, but also affects the overall flexibility and operational performance of the catheter, making it difficult to directly implement on the existing platform. Summary of the Invention

[0003] The technical purpose of the present invention is to provide a venous radiofrequency ablation system based on parallel thermocouple temperature measurement without changing the original volume, structure and doctor's operating technique of the catheter. Within the heating unit of the limited length of the catheter, by adopting a multi-point parallel temperature measurement scheme, real-time monitoring of local temperature distribution is achieved, and temperature abnormalities are judged by the real-time monitored temperature. When the temperature of a local temperature measurement point rises abnormally, the radiofrequency energy output is quickly shut down to avoid further temperature rise and prevent adverse events such as burning the tube or blood vessels.

[0004] In order to solve the above problems, the technical solution of the present invention is: The present invention provides a venous radiofrequency ablation system based on parallel thermocouple temperature measurement, which is characterized by comprising a host control module and a temperature signal transmission module connected to the host control module, a thermocouple temperature measurement module, a radiofrequency energy generation module, and a catheter heating module, wherein: A thermocouple temperature measurement module, comprising at least two parallel thermocouples, which are disposed in the heating area of an ablation catheter having a heating unit and are evenly arranged radially and / or axially along the ablation catheter to form multiple temperature measurement points for fully monitoring the heating area, and are used to monitor the temperature data of the multiple temperature measurement points in real time and transmit the data to the host control module; The temperature signal transmission module connects all thermocouples in parallel to the host control module through compensation wires to transmit the return signal, which is used to fully collect the temperature status of multiple temperature measurement points in the entire heating area; A radio frequency energy generating module, configured to adjust and output high frequency current in real time according to the control instructions to transmit stable radio frequency energy to the catheter heating module; The catheter heating module is located at the distal end of the ablation catheter and has a predetermined length to form a heating unit capable of effective heat conduction. Under the action of radiofrequency energy, the module causes current to flow through the heating wire within the heating unit to generate heat energy. The heat energy is then conducted to the vessel wall through direct contact with the vessel wall to achieve vascular closure. The host control module is used to fuse and calculate the current average temperature based on the temperature data monitored at multiple temperature measurement points, make an abnormal judgment on the average temperature based on the temperature abnormality automatic power-off control strategy, and dynamically trigger the RF energy shutdown instruction.

[0005] Preferably, the host control module further includes: determining whether the average temperature is less than a target ablation temperature; During the normal ablation phase, if the average temperature is lower than the target ablation temperature, the host control module continuously issues a radio frequency energy output instruction; If the average temperature is greater than or equal to the target ablation temperature, determining whether the average temperature is equal to the target ablation temperature; In the stable ablation stage, if the average temperature is equal to the target ablation temperature, it is determined whether the set treatment time has ended. If the set treatment time has ended, the treatment is terminated normally. If the set treatment time has not ended, the host control module maintains the current RF energy output instruction until the treatment time ends. If the average temperature is not equal to the target ablation temperature, determining whether the average temperature is greater than a temperature safety threshold; When the average temperature is less than or equal to the temperature safety threshold, continuing to execute the step of determining whether the set treatment time is ended; In the local overheating stage, when the average temperature is greater than the temperature safety threshold, an alarm operation is triggered.

[0006] Preferably, the host control module further includes: Obtain the patient's current vascular anatomical structure and real-time dynamic temperature data; Based on the temperature threshold adjustment algorithm, historical temperature data and real-time temperature change trends are analyzed to automatically adjust the target safety temperature threshold to adapt to the actual contact conditions between the ablation catheter and the blood vessel wall.

[0007] Preferably, the calculation formula for dynamically adjusting the target safe temperature threshold based on the temperature threshold adjustment algorithm is as follows: Tsafe=Tbase+α*ΔTtrend+β*σ; Among them, Tsafe is the target safety temperature threshold, Tbase is the basic safety threshold, ΔTtrend is the historical temperature change slope, σ is the standard deviation of multiple temperature measurement points, and α and β are weight coefficients.

[0008] Preferably, the host control module further includes: Synchronously collect the temperature of the first temperature measuring point T1, the second temperature measuring point T2, the third temperature measuring point T3 and the fourth temperature measuring point T4 according to a preset period; Calculate the average temperature Tavg, the standard deviation σ of multiple temperature measurement points, and the temperature change slope ΔTtrend of the first temperature measurement point temperature T1, the second temperature measurement point temperature T2, the third temperature measurement point temperature T3, and the fourth temperature measurement point temperature T4; The type of blood vessel the ablation catheter is currently operating in is determined based on the current average temperature Tavg, the standard deviation of multiple temperature measurement points σ, and the temperature change slope ΔTtrend. When the calculated standard deviation σ of the multiple temperature measurement points is greater than the first preset temperature threshold, and the temperature change rate ΔTtrend is greater than the first preset temperature change rate, it is determined that the ablation catheter is in poor contact with the curved section of the blood vessel; When the calculated average temperature Tavg is less than the preset average temperature threshold, the standard deviation σ of the multiple temperature measurement points is greater than the second preset temperature threshold, and the second preset temperature change rate is less than the second preset temperature change rate, it is determined that the ablation catheter is in the uneven heat conduction section inside the blood vessel; When the calculated standard deviation σ of the multiple temperature measurement points is less than the third preset temperature threshold, and the absolute value of the temperature change rate is less than the second preset temperature change rate under the normal trend, it is determined that the temperature distribution of the ablation catheter in the normal blood vessel segment is uniform; Among them, the first preset temperature change rate is the temperature change rate corresponding to the local temperature rising trend when the blood vessel bending section has poor contact, the second preset temperature change rate is the temperature change rate corresponding to the normal trend, the first preset temperature threshold > the second preset temperature threshold > the third preset temperature threshold, and the first preset temperature threshold is the temperature threshold corresponding to the state of poor contact of the blood vessel bending section, the second preset temperature threshold is the temperature threshold corresponding to the state of uneven heat conduction inside the blood vessel, and the third preset temperature threshold is the temperature threshold corresponding to the normal blood vessel section, that is, the state of uniform temperature distribution.

[0009] Preferably, the host control module further includes: Dynamically adjust the target safety temperature threshold and trigger control instructions based on the detected blood vessel type When a vessel is detected to be in a curved section, the system quantifies the anatomical differences and temperature change characteristics of the vessel based on a multi-parameter real-time feedback mechanism, and lowers the target safety temperature threshold to quickly respond and avoid local overheating. When uneven thermal conductivity is detected in the blood vessel, the target safety temperature threshold is raised based on the multi-parameter real-time feedback mechanism to quantify the vascular anatomical differences and temperature change characteristics to ensure that the thrombus area reaches the effective ablation temperature; When a normal blood vessel segment is detected, the default target safety temperature threshold is maintained.

[0010] Preferably, the thermocouple temperature measurement module includes a first temperature measurement point, a second temperature measurement point, a third temperature measurement point and a fourth temperature measurement point. The temperature difference of all temperature measurement points from 120° C. is maintained within a preset range, and the ablation process is in a normal state.

[0011] Preferably, the diameter of the heating unit does not exceed 2.3 mm.

[0012] Preferably, the target ablation temperature range is set to 120°C ± 3°C, and the target safety temperature threshold range is set to 130°C ± 3°C.

[0013] Preferably, the positive poles of at least two thermocouples are connected in parallel to form a positive pole merging point connected to a temperature compensation wire, and the negative poles of at least two thermocouples are connected in parallel to form a negative pole merging point and another temperature compensation wire, which are completely transmitted to the host control module through the compensation wire. When the temperature of the cold end of the thermocouple changes, the compensation wire generates a corresponding thermoelectric potential change, and at the same time, the compensation wire generates an additional thermoelectric potential due to its own characteristics. The direction of the additional thermoelectric potential is opposite to the direction of the thermoelectric potential change caused by the change in the cold end temperature of the thermocouple, thereby realizing compensation of the cold end temperature.

[0014] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art: 1. High-precision temperature monitoring This invention utilizes multiple thermocouples in parallel within the confined 2.3mm diameter of the catheter, eliminating the need for additional sensor wiring and utilizing two existing compensation wires to transmit temperature data from multiple points. This significantly overcomes the bottleneck of existing structures that prevent additional temperature measurement points due to volume limitations. It enables real-time temperature acquisition and monitoring at multiple points within the confined space of the catheter, avoiding the temperature blind spots caused by single-point temperature measurement. By collecting data from multiple measurement points within the catheter's 7cm heating zone and using an averaging algorithm to comprehensively assess temperature, the system can more accurately reflect local temperature anomalies and detect them quickly and accurately, avoiding the risk of missed reports or misjudgments associated with single-point monitoring and ensuring that the system can promptly implement power-off protection measures.

[0015] 2. Improve security The host control module used in the present invention has high-speed data processing capabilities. Once a sharp rise in the measured temperature is detected, the radio frequency energy is immediately turned off after averaging judgment, which greatly shortens the time window of continuous high temperature action, thereby reducing the probability of local overheating leading to tube and blood vessel burning. Once the local temperature is abnormal, the system can respond quickly and automatically cut off the power, reducing the local overheating time, preventing catheter or blood vessel burning accidents caused by high temperature, and ensuring patient safety. The introduction of a dynamic temperature threshold adjustment algorithm adapts to the actual conditions of different pathologies and vascular structures, further improving the safety and stability of the surgical process. After adopting a multi-point temperature measurement and data averaging algorithm, even if a local temperature measurement point has an abnormal temperature rise due to poor contact, the overall temperature average value can also reflect the problem in time, thereby avoiding a single point abnormality from masking the global problem. In particular, the design is optimized for complex situations such as excessive bending of blood vessels, wall hyperplasia, or the presence of thrombosis, effectively solving the problem of temperature out of control caused by local poor fitting, and greatly improving the safety of the operation.

[0016] 3. Compact structure and easy to implement While maintaining the original catheter size and flexible operating characteristics, the present invention optimizes the internal structure to achieve a multi-point temperature monitoring function without sacrificing other catheter functions. This design not only ensures the flexibility of the catheter in clinical use, but also effectively improves the temperature monitoring accuracy. The parallel thermocouple temperature measurement mode does not require major changes to the existing catheter diameter and internal structure, ensuring the flexibility and operability of the catheter. The original wiring is used to achieve multi-point signal return, which saves space and reduces costs and process difficulty, making it easier to promote and apply on existing product platforms. The system not only has an automatic power-off function, but also can record temperature data in real time and generate early warning reports to provide reference for doctors, while also providing data support for subsequent optimization and research and development of the product.

[0017] 4. Data recording and intelligent early warning The system not only features an automatic power-off function but also records temperature data in real time and generates early warning reports, providing a reference for doctors and data support for subsequent product optimization and development. The system records and analyzes temperature data in real time, providing a basis for intraoperative monitoring and postoperative data evaluation, while also accumulating valuable data for product improvement and clinical technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Various other advantages and benefits will become apparent to those skilled in the art by reading the following detailed description of the preferred embodiment.The accompanying drawings are only for the purpose of illustrating the preferred embodiment and are not to be considered as limiting the present invention.

[0019] Figure 1 This is a block diagram of a venous radiofrequency ablation system based on parallel thermocouple temperature measurement in an embodiment of the present invention; Figure 2 Schematic diagram of the arrangement of multi-point parallel thermocouples and temperature compensation wire connections in a heating unit in a temperature signal transmission module according to an embodiment of the present invention; Figure 3 This is a flow chart of the automatic power-off control strategy for abnormal temperature in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and functions of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they should not be understood as limiting the present invention. In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features specified as "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0021] It should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0022] See also Figure 1 As shown, the present invention provides a venous radiofrequency ablation system based on parallel thermocouple temperature measurement, including a host control module and a temperature signal transmission module connected to the host control module, a thermocouple temperature measurement module, a radiofrequency energy generation module, and a catheter heating module. Through close cooperation between the modules, real-time monitoring and automatic adjustment of the temperature state of the heating area are achieved, wherein, A thermocouple temperature measurement module, comprising at least two parallel thermocouples, which are disposed in the heating area of an ablation catheter having a heating unit and are evenly arranged radially and / or axially along the ablation catheter to form multiple temperature measurement points for fully monitoring the heating area, and are used to monitor the temperature data of the multiple temperature measurement points in real time and transmit the data to the host control module; The temperature signal transmission module connects all thermocouples in parallel to the host control module through compensation wires to transmit the return signal, which is used to fully collect the temperature status of multiple temperature measurement points in the entire heating area; A radio frequency energy generating module, configured to adjust and output high frequency current in real time according to the control instructions to transmit stable radio frequency energy to the catheter heating module; The catheter heating module is located at the distal end of the ablation catheter and has a predetermined length to form a heating unit capable of effective heat conduction. Under the action of radiofrequency energy, the module causes current to flow through the heating wire within the heating unit to generate heat energy. The heat energy is then conducted to the vessel wall through direct contact with the vessel wall to achieve vascular closure. The host control module is used to fuse and calculate the current average temperature based on the temperature data monitored at multiple temperature measurement points, make abnormal judgments on the average temperature based on the automatic power-off control strategy for temperature abnormalities, and dynamically trigger the RF energy shutdown instruction. After adopting multi-point temperature measurement and data averaging algorithms, even if a local temperature measurement point has an abnormal temperature rise due to poor contact, the overall temperature average value can also reflect the problem in time, thereby preventing a single point abnormality from masking the global problem.

[0023] Through the ingenious parallel thermocouple design and intelligent algorithm, real-time monitoring and rapid response to temperature anomalies are achieved without increasing the volume of the ablation catheter, significantly improving surgical safety. In the temperature control response mechanism, the host control module can not only make abnormal judgments based on temperature monitoring data, but also conduct historical records and trend analysis of the data, further optimize the power-off control strategy, and improve system safety and stability.

[0024] In one embodiment, the positive poles of at least two thermocouples are connected in parallel to form a positive pole merging point connected to a temperature compensation wire, and the negative poles of at least two thermocouples are connected in parallel to form a negative pole merging point connected to another temperature compensation wire, which is completely transmitted to the host control module through the compensation wire, wherein when the temperature of the cold end of the thermocouple changes, the compensation wire generates a corresponding thermoelectric potential change, and at the same time, the compensation wire generates an additional thermoelectric potential due to its own characteristics. The direction of the additional thermoelectric potential is opposite to the direction of the thermoelectric potential change caused by the change in the cold end temperature of the thermocouple, thereby achieving compensation for the cold end temperature. It can be understood that the parallel structure adopted in this embodiment is that the positive poles (T+) of all thermocouples are connected in parallel to the same compensation wire A, and the negative poles (T-) are connected in parallel to wire B. A compensation wire that matches the thermocouple is used, such as a K-type thermocouple with a nickel-chromium-nickel-silicon compensation wire, to ensure signal transmission accuracy. Figure 2Figure 1 shows a schematic diagram of the multi-point parallel thermocouple arrangement and temperature compensation wire connection within the thermocouple temperature signal transmission module, or heating unit 1. It illustrates four or more thermocouples 2 evenly distributed radially within a 7cm heating zone and their parallel connection. One end of each of the four thermocouples is connected to the thermocouple parallel connection via one of the existing compensation wires 3. The other end of each of the four thermocouples is connected to the thermocouple parallel connection via another existing compensation wire 3, ultimately connecting to the host control module. Multiple thermocouple temperature measurement points are evenly distributed radially and / or axially within the 7cm heating unit of the ablation catheter. For example, two or more temperature measurement points may be arranged in a radial region, with the specific number adjustable based on clinical needs. Each temperature measurement point is connected in parallel, and all thermocouples transmit data back to the host via the two existing compensation wires. This solution utilizes the principle of parallel connection, without adding additional wiring complexity or significantly changing the catheter diameter or internal structure. The carefully designed placement of the thermocouples ensures that the temperature status of the entire heating unit is fully captured, thus avoiding the information blind spots associated with single-point monitoring. For example, when four thermocouples are connected in parallel, the voltage detected by the host is the weighted average of the electromotive force (EMF) of each thermocouple. If the outputs of the four thermocouples are V1, V2, V3, and V4, respectively, the host measures the voltage: Tavg = (V1 + V2 + V3 + V4) / 4. The host converts Vavg to the average temperature Tavg using a thermocouple scale. Four thermocouples are evenly arranged circumferentially within a 7cm heating unit (at 90° intervals) to cover possible hotspots. If a thermocouple breaks, the parallel circuit automatically ignores its signal (the output voltage approaches 0). The system can still operate based on the remaining thermocouples, but a fault indication is required. In the above method, all parallel thermocouples can be of the same model and batch to ensure consistent temperature-voltage curves and avoid calculation errors due to individual differences. The length and resistance of each thermocouple lead are kept as consistent as possible to reduce signal offset caused by uneven line impedance. A single temperature sensor is installed at the cold junction, where the compensation wire connects to the measurement circuit, on the host side to uniformly compensate for the cold junction error of all thermocouples. Since all thermocouples share a common cold junction, the compensation value is directly applied to Vavg. The design of parallel thermocouples and shared compensation wires enables multi-point temperature monitoring without increasing the catheter diameter. This utilizes the voltage averaging characteristics of parallel thermocouples; ensures accuracy through hardware uniformity and cold junction compensation; and combines algorithms to quickly identify local overheating. This makes it suitable for medical catheter scenarios with limited space, such as hollow blood vessels, significantly improving safety.

[0025] In one embodiment, the thermocouple temperature measurement module includes a first temperature measurement point, a second temperature measurement point, a third temperature measurement point, and a fourth temperature measurement point. The temperature difference between all temperature measurement points and 120°C is kept within a preset range, and the ablation process is in a normal state. Figure 1 and Figure 2In order to accurately monitor the temperature of the heating area, the overall structure of the ablation catheter has four thermocouple temperature measuring points evenly arranged along the circumference of the catheter within a 7cm working area. These four temperature measuring points are connected in parallel, and the temperature signal is transmitted to the host control module through the original two compensation wires. During the radiofrequency ablation process, the heating wire actively generates heat and conducts the heat energy to the blood vessel through direct contact with the blood vessel wall. The system monitors the temperature of the four temperature measuring points in real time. When the temperature of all temperature measuring points remains at around 120°C, it indicates that the catheter is in good contact with the blood vessel wall and the ablation process is normal. If the temperature of a certain temperature measuring point rises sharply, for example to 250°C, due to complex blood vessel structure, local blood vessel wall hyperplasia or the presence of thrombosis, the host immediately calculates the temperature average of the four temperature measuring points. If it is found that the average temperature significantly exceeds the preset safety threshold, it will trigger the radiofrequency energy shutdown command to prevent the local temperature from rising further and avoid burning the tube or blood vessel.

[0026] In one embodiment, the diameter of the heating unit does not exceed 2.3 mm, which can easily enter thinner blood vessels such as coronary arteries and cerebral arteries, thereby expanding the scope of surgical application; a diameter of no more than 2.3 mm reduces mechanical pressure on the blood vessel wall and reduces the risk of vascular spasm, tearing or perforation, and is particularly suitable for fragile or severely diseased blood vessels; it can more accurately locate diseased areas such as thrombi or plaques, avoid affecting surrounding healthy tissues, and improve ablation effects; it reduces the diffusion of heat to surrounding tissues and reduces the risk of thermal damage to non-target areas; it is easier to contact blood and tissue evenly within the blood vessel, reducing local hot spots and temperature unevenness, thereby improving the uniformity of temperature distribution; because the heating unit is in closer contact with the blood vessel wall, the temperature standard deviation (σ) of multiple temperature measurement points is reduced, which helps the safety threshold calculation formula to more accurately reflect the actual temperature distribution. The temperature measurement point of this heating unit is closer to the vessel wall, enabling more sensitive detection of local temperature changes such as Tmax and σ, improving the accuracy of the burnout risk prediction model. In the event of abnormally high or uneven temperature distribution, the system can respond more quickly and force power off, further reducing the risk of burnout. This diameter heating unit can more easily navigate curved or bifurcated vessels, reducing operational difficulties and vessel damage caused by oversized devices. In areas of thrombus or plaque, this heating unit can be closer to the lesion, improving ablation efficiency while avoiding excessive damage to vessels behind the thrombus. This heating unit is also easier to deliver to the target site via a guidewire or catheter, reducing the technical requirements of the physician. For example, in scenario 1: ablation of small vessels such as coronary arteries, a heating unit with a diameter of 2.0mm can easily access a coronary artery with a diameter of 2.5mm, avoiding vessel damage caused by oversized devices. This allows for precise ablation in the thrombus area while minimizing thermal damage to surrounding healthy vessels. The low temperature standard deviation (σ) of the temperature measurement point allows for a more accurate safety threshold calculation formula, resulting in a more sensitive burnout risk prediction model. Scenario 2: Ablation of curved blood vessels. The device is equipped with a heating unit with a diameter of 2.3 mm (the maximum value). This allows smooth passage through curved blood vessels, reduces operational delays or vessel wall damage caused by oversized devices, achieves uniform ablation in curved segments, and avoids local overheating or the risk of tube burning.

[0027] In one embodiment, the target ablation temperature range is set to 120°C ± 3°C, and the target safety temperature threshold range is set to 130°C ± 3°C. The 120°C ablation temperature ensures therapeutic efficacy, while the 130°C safety threshold provides a protective margin. The two work together to achieve a balance between "precise ablation" and "safety control." The 120°C to 130°C range ensures ablation efficiency while avoiding the risks of temperatures that are too low (ineffective ablation) or too high (vascular damage). Compared to higher temperatures, such as above 130°C, the heat at 120°C is more concentrated, reducing thermal diffusion damage to surrounding healthy tissue.

[0028] In one embodiment, in order to improve the adaptability of the system in complex clinical environments, this embodiment further introduces a dynamic temperature threshold adjustment algorithm based on the parallel structure. During actual surgery, there are large individual differences in the anatomical structure of blood vessels, such as excessive bending, local wall hyperplasia and the presence of thrombus, which will affect the local temperature distribution. The dynamic temperature threshold adjustment algorithm automatically adjusts the safety threshold by analyzing historical temperature data and real-time temperature change trends, thereby ensuring more accurate temperature monitoring and response. For example, in some special cases, the system can appropriately increase or decrease the threshold to adapt to the actual contact between the catheter and the blood vessel wall. Figure 3 As shown, the algorithm effectively improves the safety and stability of the ablation process. Specifically, the host control module further includes: determining whether the average temperature is less than a target ablation temperature; During the normal ablation phase, if the average temperature is lower than the target ablation temperature, the host control module continuously issues a radio frequency energy output instruction; If the average temperature is greater than or equal to the target ablation temperature, determining whether the average temperature is equal to the target ablation temperature; In the stable ablation stage, if the average temperature is equal to the target ablation temperature, it is determined whether the set treatment time has ended. If the set treatment time has ended, the treatment is terminated normally. If the set treatment time has not ended, the host control module maintains the current RF energy output instruction until the treatment time ends. If the average temperature is not equal to the target ablation temperature, determining whether the average temperature is greater than a temperature safety threshold; When the average temperature is less than or equal to the temperature safety threshold, continuing to execute the step of determining whether the set treatment time is ended; In the local overheating stage, when the average temperature is greater than the temperature safety threshold, an alarm operation is triggered.

[0029] Normal ablation stage Goal: To make the average temperature reach the target ablation temperature as quickly as possible to initiate effective ablation.

[0030] The principles of this embodiment are as follows: 1. During the normal ablation phase, when the average temperature is lower than the target ablation temperature, the system continuously issues RF energy output instructions, gradually heating the tissue to the target temperature. For example, if the target ablation temperature is 120°C and the average temperature is 115°C, the system maintains RF energy output until the temperature approaches 120°C. 2. During the stable ablation phase, when the average temperature reaches the target ablation temperature, the system enters the stable ablation phase and starts timing the set treatment time, such as 120 seconds. If the treatment time has not ended and the temperature remains at the target value, the system maintains the current RF energy output; if the treatment time ends, the system ends the operation normally. For example, if the target ablation temperature is 120°C and the treatment time is 120 seconds, if the average temperature stabilizes at 120°C, the system maintains energy output until the end of 120 seconds. 3. During the local overheating phase, when the average temperature exceeds the temperature safety threshold, such as 130°C, the system immediately triggers an alarm operation, such as an audible and visual alarm, or a screen prompt, and stops RF energy output. For example, if the safety threshold is 130°C, if the average temperature rises to 132°C, the system triggers an alarm and stops energy output to prevent overheating. 4. Dual Temperature and Time Determination: When the average temperature reaches the target ablation temperature, the system starts a timer. Ablation is considered successful only if the temperature remains stable within the set treatment time. If the temperature does not reach the target value within the treatment time, the system will not terminate the operation prematurely, preventing inadequate ablation due to insufficient temperature. By determining the relationship between the average temperature, the target ablation temperature, and the safety threshold in stages, combined with the set treatment time, the system can: precisely control the ablation process, ensuring that the temperature quickly reaches the target value and remains stable; effectively prevent local overheating, and reduce the risk of tissue damage through safety thresholds and alarm mechanisms; improve surgical efficiency, and adapt to the needs of complex vascular scenarios through automated control and dual temperature + time determination, which reduces manual intervention. Furthermore, this solution utilizes dual threshold protection: the target ablation temperature Tsafe (a primary threshold) for routine warnings; and the temperature safety threshold Tmax (e.g., 150°C) (a secondary threshold) that triggers power outages if any single point temperature exceeds the target value, preventing algorithm failure. When a power outage is triggered, the previous 30 seconds of temperature curves are automatically saved for postoperative analysis. Through dynamic average temperature determination and real-time threshold adjustment, the system achieves: precise response: 10ms power-off speed, covering both local hotspots and global temperature rise; personalized adaptation: dynamic algorithms address complex anatomy such as vascular tortuosity and thrombosis; and multiple protections: hardware acceleration, dual thresholds, and data backtracking ensure safety in extreme scenarios. Its clinical value lies in significantly reducing complication rates while avoiding incomplete ablation caused by overly conservative treatment.

[0031] In one embodiment, the host control module further includes: Obtain the patient's current vascular anatomical structure and real-time dynamic temperature data; Based on the temperature threshold adjustment algorithm, historical temperature data and real-time temperature change trends are analyzed to automatically adjust the target safety temperature threshold to adapt to the actual contact conditions between the ablation catheter and the blood vessel wall.

[0032] For example, the temperature measured by parallel thermocouples is the average of the individual thermocouple temperatures. For example, if there are four thermocouples connected in parallel, with temperatures T1, T2, T3, and T4, the host computer measures a temperature of T = (T1 + T2 + T3 + T4) / 4. The host control module collects and processes data based on the real-time temperature signals from each thermocouple. For example, if the target temperature is 120°C and the safety threshold is 130°C, when all measured temperatures are within the safe range (e.g., T1, T2, T3, and T4 are all 120°C), the system assumes good contact between the catheter and the vessel wall at T = 120°C. However, if the temperature at a particular measured temperature point rises sharply due to localized poor contact (e.g., T1, T2, T3 are all 120°C and T4 is 250°C), the host computer will measure an average temperature of 152.5°C, thus exceeding the safety threshold. Once the average temperature exceeds the safety threshold, a command is immediately issued to shut down the RF energy output to ensure the safety of the treatment process.

[0033] In one embodiment, the calculation formula for dynamically adjusting the target safe temperature threshold based on the temperature threshold adjustment algorithm is as follows: Tsafe=Tbase+α*ΔTtrend+β*σ; Among them, Tsafe is the target safety temperature threshold; Tbase is the basic safety threshold, such as 130°C; ΔTtrend is the historical temperature change slope, reflecting the heating trend; σ is the standard deviation of multiple temperature measurement points, reflecting the uniformity of temperature distribution at the temperature measurement points; α and β are weight coefficients. Dynamic adjustment of the threshold through the above calculation method can dynamically adapt to the heating trend and avoid local overheating caused by rapid heating; quantify temperature uniformity and increase the safety threshold when the temperature distribution is uneven to ensure the safety of abnormal areas; through flexible adjustment of the weight coefficient, it can adapt to different blood vessel types and clinical needs, thereby improving the safety and effectiveness of ablation surgery.

[0034] Furthermore, the safety threshold calculation formula is as follows: Tsafe=Tbase−α*σ−β*max(0,ΔTtrend)+γ*Hthrombus, where the uniformity weight α=0.5, the trend weight β=3, the thrombus compensation γ=5, and Hthrombus: the thrombus flag, triggered by a sudden increase in σ and ΔTtrend<0.

[0035] Burning tube risk prediction model: Pburn=1 / [1+e^ −(0.1Tmax+0.05σ−12)], Tmax is the highest temperature among the four points, reflecting the local hotspot. Temperature dispersion σ reflects the degree of contact unevenness. A forced power outage occurs when Pburn > 0.7. For example, if Tmax = 145°C and σ = 10°C, Pburn = 0.82, triggering protection. This model reduces the tube burnout rate from 0.3% to 0.02%.

[0036] Case 1: Ablation at a vascular bifurcation Original data: T = [121, 119, 155, 117] °C, calculated: Tavg = 128 °C, σ = 16.8 °C, ΔTtrend = +4.2 °C / s; Dynamic adjustment: Tsafe=130-0.5×16.8-10×4.2≈98℃; Decision: If Tavg (128°C) > T_safe (98°C), power off immediately to avoid perforation of thin-walled blood vessels at the bifurcation (which would be missed by traditional single-point monitoring).

[0037] Case 2: Ablation of chronic thrombus Original data: T = [105, 108, 103, 110] °C, calculated: Tavg = 106.5 °C, σ = 2.9 °C, ΔTtrend = +0.8 °C / s; Dynamic adjustment: Ttarget = 120 + 0.3 × 2.9 ≈ 121°C, Tsafe = 130 + 5 (thrombus compensation) = 135°C; Decision: Maintain energy output until Tavg reaches 121°C, the thrombus is completely dissolved, and no carbonization of the tube wall occurs.

[0038] In one embodiment, the host control module further includes: Synchronously collect the temperatures of the first, second, third, and fourth temperature measurement points T1, T2, T3, and T4 at a preset period. For example, record the temperatures of T1 to T4 every 100ms and calculate Tavg, σ, and ΔTtrend, which can be the slope over the past 5 seconds. Calculate the average temperature Tavg, standard deviation σ of multiple temperature measurement points, and temperature change slope ΔTtrend of the first, second, third, and fourth temperature measurement points T1, T2, T3, and T4, based on a sliding window (e.g., the past five Tavg values) and a least squares fitting slope of a 500ms time window. Alternatively, enable the ADS1248's 4-channel synchronous sampling mode, continuously sampling 100 points per channel (1kHz sampling rate, completed within 10ms), read the PT100 resistance value, convert it to the cold-end temperature T_cold, and correct the temperature: Ti=Tiraw+Tcold(i=1,2,3,4).

[0039] The type of blood vessel the ablation catheter is currently operating in is determined based on the current average temperature Tavg, the standard deviation of multiple temperature measurement points σ, and the temperature change slope ΔTtrend. When the calculated standard deviation σ of multiple temperature measurement points exceeds the first preset temperature threshold and the temperature change rate ΔTtrend exceeds the first preset temperature change rate, the ablation catheter is judged to have poor contact in the curved section of the vessel. Case 1: If σ exceeds 8°C, for example, if the temperature difference between the four temperature measurement points is large (T1 = 120°C, T2 = 118°C, T3 = 125°C, and T4 = 150°C), this indicates that the catheter is partially suspended from the vessel wall, preventing uniform heat transfer. Furthermore, if ΔTtrend exceeds 3°C / s, this indicates that the temperature of the suspended point has rapidly risen due to heat accumulation. For example, if T4 rises from 120°C to 150°C in 1 second, the threshold is adjusted: Tsafe = Tbase − 0.5σ − 10ΔTtrend. For example, if Tbase = 130°C, σ = 15°C, ΔTtrend = 4°C / s, Tsafe = 130 − 7.5 − 40 = 82.5°C. This significantly lowers the threshold to quickly respond to the risk of local overheating.

[0040] When the calculated average temperature Tavg < the preset average temperature threshold, the standard deviation σ of multiple temperature measurement points > the second preset temperature threshold, and the second preset temperature change rate < the second preset temperature change rate, it is determined that the ablation catheter is in the uneven thermal conductivity section inside the blood vessel, that is, the vascular proliferation / thrombosis area; Case 2: Tavg < 115°C, the thrombus has poor thermal conductivity, and the overall temperature is low, such as T1 = 110 ± 5°C, T2 = 105 ± 8°C, if σ > 5°C And ΔTtrend<1℃ / s, which means that the temperature fluctuates greatly but there is no trend of rapid temperature rise, indicating that the internal structure of the thrombus is uneven. The target temperature threshold is adjusted as follows: Ttarget=Tstd+0.3σ, and the safety threshold compensation is as follows: Tsafe=Tbase+γ*Hthrombus, where γ=5℃ is the thrombus compensation coefficient and Hthrombus is the thrombus flag. That is, it is set to 1 when σ suddenly increases and ΔTtrend<0. For example, σ=6℃, the standard Tstd=120℃+1.8≈122℃, and Tsafe=130+5=135℃. The target temperature is appropriately increased to penetrate the thrombus, and the safety threshold is relaxed to avoid accidental power off, ensuring that the thrombus area reaches the effective ablation temperature and avoiding incomplete treatment due to local hypothermia.

[0041] When the calculated standard deviation σ of multiple temperature measurement points is less than the third preset temperature threshold, and the absolute value of the temperature change rate is less than the second preset temperature change rate, it is determined that the ablation catheter is in a normal vascular segment with uniform temperature distribution; Case three: σ<3°C, ΔTtrend≈0°C / s, threshold strategy: maintain Tsafe=130°C, Ttarget=120°C, no dynamic adjustment is required, and energy output is controlled according to standard procedures.

[0042] Among them, the first preset temperature change rate is the temperature change rate corresponding to the local temperature rising trend when the blood vessel bending section has poor contact, the second preset temperature change rate is the temperature change rate corresponding to the normal trend, the first preset temperature threshold > the second preset temperature threshold > the third preset temperature threshold, and the first preset temperature threshold is the temperature threshold corresponding to the state of poor contact of the blood vessel bending section, the second preset temperature threshold is the temperature threshold corresponding to the state of uneven heat conduction inside the blood vessel, and the third preset temperature threshold is the temperature threshold corresponding to the normal blood vessel section, that is, the state of uniform temperature distribution.

[0043] In one embodiment, the host control module further includes: Dynamically adjust the target safety temperature threshold and trigger control instructions based on the detected blood vessel type. By identifying the blood vessel type (curved / thrombus / normal) in real time, the threshold strategy is dynamically adjusted to achieve personalized treatment. When a vessel is detected in a curved section, a multi-parameter real-time feedback mechanism is used to quantify vascular anatomical differences and temperature change characteristics, lowering the target safety temperature threshold to quickly respond and avoid local overheating. By lowering the safety threshold in real time, for example, dynamically adjusting it from 130°C to 80°C, when the catheter is suspended and causes a sudden local temperature rise, such as a single point reaching 150°C, the power is quickly cut off to avoid catheter meltdown or vessel perforation. The vessel wall in the curved section is thinner, and the dynamic response can prevent vessel rupture caused by accumulated thermal damage. The principle is as follows: Multi-parameter triggering: When σ>8°C (uneven contact) and ΔTtrend>3°C / s (rapid temperature rise), the formula Tsafe=Tbase-0.5σ-10ΔTtrend is used, and the threshold is automatically lowered for early intervention. When uneven thermal conductivity is detected in the blood vessel, the target safety temperature threshold is raised based on the multi-parameter real-time feedback mechanism to quantify the vascular anatomical differences and temperature change characteristics to ensure that the thrombus area reaches the effective ablation temperature. The target temperature is raised from 120°C to 122°C to compensate for the problem of poor thermal conductivity of the thrombus and ensure that deep thrombi reach the effective ablation temperature; the safety threshold is relaxed from 130°C to 135°C to prevent the system from prematurely stopping energy output due to the overall low temperature of the thrombus area. The principle is: dual threshold adjustment: target temperature: Ttarget=Tstd+0.3σ (σ compensates for uneven thermal conductivity), safety threshold: Tsafe=Tbase+5°C (thrombus flag triggering); When a normal blood vessel segment is detected, the default target safety temperature threshold is maintained, with fixed thresholds Ttarget = 120°C and Tsafe = 130°C to reduce the system's computational load, improve response stability, avoid unnecessary dynamic adjustments, and ensure uniform ablation efficiency.

[0044] The multi-parameter real-time feedback mechanism integrates three parameters: temperature mean (Tavg), standard deviation (σ), and rate of change (ΔTtrend), covering both spatial uniformity and temporal trend risks. For example, the multi-parameter real-time feedback mechanism can also utilize dual spatial and temporal monitoring, with σ reflecting contact uniformity (spatial dimension) and ΔTtrend reflecting the rate of temperature rise (temporal dimension). Thresholds are updated every 100ms, forming a real-time closed loop of "monitoring-calculation-adjustment." The response latency is less than 10ms, far below the time window for thermal damage (typically >100ms).

[0045] Normal: If the catheter adheres evenly to the vessel wall, temperatures at all points are close (e.g., T1-T4 ≈ 120°C), and Tavg ≈ 120°C, the system maintains RF energy output. Abnormal: Localized overheating: A temperature spike at a specific point, such as T4 = 250°C, or a significant increase in Tavg, such as 152.5°C, triggers a power-off protection. Overall low temperature: If Tavg < target temperature, such as 100°C, indicates insufficient energy and requires increased output.

[0046] The present invention provides a venous radiofrequency ablation system based on parallel thermocouple temperature measurement. Without changing the original catheter size or the physician's operating habits, this system, through internal structural optimization and multi-point temperature monitoring, addresses the safety risks of temperature unevenness caused by poor local adhesion between the catheter and the vessel wall, which can lead to tube and vessel burns. This technical solution offers advantages such as compact structure, strong adaptability, rapid response, and low cost. It can significantly improve the safety and reliability of venous radiofrequency ablation procedures and has broad clinical application prospects and promotional value.

[0047] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the scope of protection of the present invention.

Claims

1. A venous radiofrequency ablation system based on parallel thermocouple temperature measurement, characterized in that: It includes a host control module and a temperature signal transmission module connected to the host control module, a thermocouple temperature measurement module, a radio frequency energy generation module, and a catheter heating module, wherein: A thermocouple temperature measurement module, comprising at least two parallel thermocouples, which are disposed in the heating area of an ablation catheter having a heating unit and are evenly arranged radially and / or axially along the ablation catheter to form multiple temperature measurement points for fully monitoring the heating area, and are used to monitor the temperature data of the multiple temperature measurement points in real time and transmit the data to the host control module; The temperature signal transmission module connects all thermocouples in parallel to the host control module through compensation wires to transmit the return signal, which is used to fully collect the temperature status of multiple temperature measurement points in the entire heating area; A radio frequency energy generating module, configured to adjust and output high frequency current in real time according to the control instructions to transmit stable radio frequency energy to the catheter heating module; The catheter heating module is located at the distal end of the ablation catheter and has a predetermined length to form a heating unit capable of effective heat conduction. Under the action of radiofrequency energy, the module causes current to flow through the heating wire within the heating unit to generate heat energy. The heat energy is then conducted to the vessel wall through direct contact with the vessel wall to achieve vascular closure. The host control module is used to fuse and calculate the current average temperature based on the temperature data monitored at multiple temperature measurement points, make an abnormal judgment on the average temperature based on the temperature abnormality automatic power-off control strategy, and dynamically trigger the RF energy shutdown instruction.

2. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement according to claim 1, characterized in that: The host control module further includes: determining whether the average temperature is less than a target ablation temperature; During the normal ablation phase, if the average temperature is lower than the target ablation temperature, the host control module continuously issues a radio frequency energy output instruction; If the average temperature is greater than or equal to the target ablation temperature, determining whether the average temperature is equal to the target ablation temperature; In the stable ablation stage, if the average temperature is equal to the target ablation temperature, it is determined whether the set treatment time has ended. If the set treatment time has ended, the treatment is terminated normally. If the set treatment time has not ended, the host control module maintains the current RF energy output instruction until the treatment time ends. If the average temperature is not equal to the target ablation temperature, determining whether the average temperature is greater than a temperature safety threshold; When the average temperature is less than or equal to the temperature safety threshold, continuing to execute the step of determining whether the set treatment time is ended; In the local overheating stage, when the average temperature is greater than the temperature safety threshold, an alarm operation is triggered.

3. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement according to claim 1, characterized in that: The host control module further includes: Obtain the patient's current vascular anatomical structure and real-time dynamic temperature data; Based on the temperature threshold adjustment algorithm, historical temperature data and real-time temperature change trends are analyzed to automatically adjust the target safety temperature threshold to adapt to the actual contact conditions between the ablation catheter and the blood vessel wall.

4. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement as claimed in claim 3, characterized in that: The calculation formula for dynamically adjusting the target safe temperature threshold based on the temperature threshold adjustment algorithm is as follows: Tsafe=Tbase+α*ΔTtrend+β*σ; Among them, Tsafe is the target safety temperature threshold, Tbase is the basic safety threshold, ΔTtrend is the historical temperature change slope, σ is the standard deviation of multiple temperature measurement points, and α and β are weight coefficients.

5. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement as claimed in claim 1, characterized in that: The host control module further includes: Synchronously collect the temperature of the first temperature measuring point T1, the second temperature measuring point T2, the third temperature measuring point T3 and the fourth temperature measuring point T4 according to a preset period; Calculate the average temperature Tavg, the standard deviation σ of multiple temperature measurement points, and the temperature change slope ΔTtrend of the first temperature measurement point temperature T1, the second temperature measurement point temperature T2, the third temperature measurement point temperature T3, and the fourth temperature measurement point temperature T4; The type of blood vessel the ablation catheter is currently operating in is determined based on the current average temperature Tavg, the standard deviation of multiple temperature measurement points σ, and the temperature change slope ΔTtrend. When the calculated standard deviation σ of the multiple temperature measurement points is greater than the first preset temperature threshold, and the temperature change rate ΔTtrend is greater than the first preset temperature change rate, it is determined that the ablation catheter is in poor contact with the curved section of the blood vessel; When the calculated average temperature Tavg is less than the preset average temperature threshold, the standard deviation σ of the multiple temperature measurement points is greater than the second preset temperature threshold, and the second preset temperature change rate is less than the second preset temperature change rate, it is determined that the ablation catheter is in the uneven heat conduction section inside the blood vessel; When the calculated standard deviation σ of the multiple temperature measurement points is less than the third preset temperature threshold, and the absolute value of the temperature change rate is less than the second preset temperature change rate under the normal trend, it is determined that the temperature distribution of the ablation catheter in the normal blood vessel segment is uniform; Among them, the first preset temperature change rate is the temperature change rate corresponding to the local temperature rising trend when the blood vessel bending section has poor contact, the second preset temperature change rate is the temperature change rate corresponding to the normal trend, the first preset temperature threshold > the second preset temperature threshold > the third preset temperature threshold, and the first preset temperature threshold is the temperature threshold corresponding to the state of poor contact of the blood vessel bending section, the second preset temperature threshold is the temperature threshold corresponding to the state of uneven heat conduction inside the blood vessel, and the third preset temperature threshold is the temperature threshold corresponding to the normal blood vessel section, that is, the state of uniform temperature distribution.

6. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement as claimed in claim 5, characterized in that: The host control module further includes: Dynamically adjust the target safety temperature threshold and trigger control instructions based on the detected blood vessel type When a vessel is detected to be in a curved section, the system quantifies the anatomical differences and temperature change characteristics of the vessel based on a multi-parameter real-time feedback mechanism, and lowers the target safety temperature threshold to quickly respond and avoid local overheating. When uneven thermal conductivity is detected in the blood vessel, the target safety temperature threshold is raised based on the multi-parameter real-time feedback mechanism to quantify the vascular anatomical differences and temperature change characteristics to ensure that the thrombus area reaches the effective ablation temperature; When a normal blood vessel segment is detected, the default target safety temperature threshold is maintained.

7. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement as claimed in claim 1, characterized in that: The thermocouple temperature measurement module includes a first temperature measurement point, a second temperature measurement point, a third temperature measurement point and a fourth temperature measurement point. The temperature difference of all temperature measurement points is kept within a preset range with respect to 120° C., and the ablation process is in a normal state.

8. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement as claimed in claim 1, characterized in that: The diameter of the heating unit does not exceed 2.3 mm.

9. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement as claimed in claim 1, characterized in that: The target ablation temperature range was set to 120°C ± 3°C, and the target safety temperature threshold range was set to 130°C ± 3°C.

10. The venous radiofrequency ablation system based on parallel thermocouple temperature measurement according to claim 1, characterized in that: The positive poles of at least two thermocouples are connected in parallel to form a positive pole merging point connected to a temperature compensation wire, and the negative poles of at least two thermocouples are connected in parallel to form a negative pole merging point connected to another temperature compensation wire, and are completely transmitted to the host control module through the compensation wire. When the temperature of the cold end of the thermocouple changes, the compensation wire generates a corresponding thermoelectric potential change. At the same time, the compensation wire generates an additional thermoelectric potential due to its own characteristics. The direction of the additional thermoelectric potential is opposite to the direction of the thermoelectric potential change caused by the change in the cold end temperature of the thermocouple, thereby realizing compensation of the cold end temperature.

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