A radio frequency ablation device calibration apparatus

Abstract

The application discloses a kind of radio frequency ablation equipment calibration devices, including shell, circuit integration panel is equipped in shell, the front of shell is equipped with operating display screen and 6 wiring ports, respectively, excitation output port, signal return port, ablation electrode port, neutral electrode port, platinum resistance temperature sensor interface 1 and platinum resistance temperature sensor interface 2;The back of shell is equipped with exhaust fan;The circuit integration panel is mainly used for the processing of radio frequency ablation quality control data, including central processing unit, analog-digital conversion module, display module, time module, radio frequency high voltage signal processing circuit, output power detection circuit and temperature detection circuit;The device uses high-voltage differential, non-inductive resistance system, precision temperature and other multi-sensor integrated system, effectively improves the calibration quality control work of radio frequency ablation equipment, so that the calibration of radio frequency ablation equipment is more standardized and accurate.

Description

Technical Field

[0001] This invention relates to the field of medical device calibration technology, and in particular to a calibration device for radiofrequency ablation equipment. Background Technology

[0002] With the rapid development of modern medical technology, radiofrequency ablation, as a minimally invasive treatment, has shown great clinical application potential in areas such as minimally invasive cardiac surgery, tumor treatment, and pain management. Radiofrequency ablation devices emit high-frequency currents into the target tissue, using radiofrequency energy to generate heat within the tissue, causing thermal coagulation and necrosis of the lesion area, thereby achieving the therapeutic goal. The therapeutic effect of radiofrequency ablation surgery is highly dependent on the accuracy and stability of various parameters output by the ablation device, including the output power of the radiofrequency energy, precise control of the frequency, and real-time monitoring of the ablation temperature. Radiofrequency ablation emission frequency and energy are interdependent. Within a certain range, increasing the frequency can improve energy transfer efficiency, allowing the tissue to heat up more quickly. However, excessively high frequencies can also lead to tissue overheating and damage, requiring precise matching between frequency and energy. Excessive radiofrequency energy may directly cause excessive tissue temperature rise and damage, which may be permanent, affecting the normal function of the patient's organs and tissues. Insufficient radiofrequency energy may not effectively eliminate abnormal lesions in the target area, leading to poor surgical results or even surgical failure.

[0003] The physical parameters of radiofrequency ablation equipment, such as frequency, energy, and temperature, directly affect patient safety and the effectiveness of ablation surgery. Therefore, regular metrological calibration of key parameters of radiofrequency ablation equipment is of significant social importance. To ensure the stable and reliable quality of radiofrequency ablation equipment, avoid endangering patient safety due to performance issues, and guarantee the traceability of the measurement values ​​of core parameters of radiofrequency ablation equipment, it is urgently necessary to develop an intelligent testing and calibration device to establish an automatic calibration system for radiofrequency ablation equipment. Summary of the Invention

[0004] The purpose of this invention is to provide a calibration device for radio frequency ablation equipment. It utilizes highly integrated sensing technologies such as high-voltage differential detection, high-frequency non-inductive load, time-frequency synchronization, and impedance detection to detect key ablation parameters, effectively improving the calibration quality control of radio frequency ablation equipment and making the calibration process more standardized and accurate.

[0005] The technical solution adopted in this invention is as follows: This invention utilizes a housing as a carrier for device protection. An operation display screen and port interfaces are located on the front of the housing. An integrated circuit panel inside the housing utilizes highly integrated sensing technologies such as high-voltage differential detection, high-frequency non-inductive load, time-frequency synchronization, and impedance detection to detect key ablation parameters. The radiofrequency ablation equipment calibration device can provide simulated human body impedance, allowing the radiofrequency energy output from the ablation equipment to be directly applied to the measurement system through surgical electrodes. The device is designed with sensing circuits for high-voltage attenuation, temperature, time, and impedance detection. The sensor output electrical signals are amplified and acquired by analog-to-digital signal amplification circuits, and then the measurement data is transmitted to a microprocessor via an analog-to-digital conversion circuit. Data processing software calculates the measured values ​​of parameters such as ablation power, impedance, frequency, temperature, and time. Finally, the measurement results are displayed on the human-machine interface display screen, making the quality control and calibration of the radiofrequency ablation equipment more standardized and accurate. Attached Figure Description

[0006] Figure 1 This is a three-dimensional structural view of the present invention; Figure 2 This is a block diagram of the circuit system of the present invention; Figure 3 This is a circuit diagram of the high voltage attenuation module and waveform compensation module of the present invention; Figure 4 This is a circuit diagram of the signal amplification module and the differential-to-single converter module of the present invention; Figure 5 This is a circuit diagram of the temperature measurement system of the present invention; Figure 6 This is the equivalent circuit for attenuation and sampling of high-frequency signals in this invention. Detailed Implementation

[0007] Radiofrequency ablation equipment has a wide range of applications. Its production and use mainly refer to standards such as YY / T 0954-2016 "Radiofrequency Ablation Equipment", YY 0860-2011 "Cardiac Radiofrequency Ablation Therapy Equipment", YY 0897-2013 "ENT Radiofrequency Ablation Equipment" and YY 0776-2010 "Liver Radiofrequency Ablation Therapy Equipment". The above standards have detailed requirements for the technical performance and indicators of radiofrequency ablation equipment. This invention provides a feasible and effective calibration scheme to make the quality control of radiofrequency ablation equipment more standardized and accurate.

[0008] like Figure 1As shown, the present invention includes a housing 1, an integrated circuit panel inside the housing 1, and an operation display screen 2 on the front of the housing 1 for setting parameters and displaying data during the calibration process; the display screen is located on the right side of the front of the housing 1 for easy operation and viewing. An exhaust fan is located on the back of the housing 1. The device generates heat during operation and requires cooling and heat dissipation. The circuit control and principle of the exhaust fan are existing technologies and will not be described in detail here.

[0009] The front of the housing 1 also has six connection ports: excitation output port A, signal return port B, ablation electrode port C, neutral electrode port D, platinum resistance temperature sensor interface 1E, and platinum resistance temperature sensor interface 2F. From the outside, the device of this invention has six interfaces on the left side of the front. Impedance detection requires an output voltage excitation source; the excitation current returns to the feedback loop after passing through the resistor under test. The instrument surface has an excitation output terminal and a signal return terminal. The instrument itself has a platinum resistance temperature sensor for liquid temperature comparison, with sensor interface 1 and sensor interface 2. For power and frequency measurement, the instrument itself has an ablation electrode and a neutral electrode.

[0010] like Figure 2 As shown, the integrated circuit panel is mainly used for processing radio frequency ablation quality control data, including a central processing unit (CPU), an analog-to-digital converter (ADC), a display module, a timing module, a radio frequency high-voltage signal processing circuit, an output power detection circuit, and a temperature detection circuit. The signal input terminal of the CPU is connected to the signal output terminal of the ADC, the first signal transmission terminal of the CPU is connected to the display module, and the second signal transmission terminal of the CPU is connected to the timing module. The signal transmission terminals of the radio frequency high-voltage signal processing circuit, the output power detection circuit, and the temperature detection circuit are all connected to the ADC, and are sent to the CPU after analog-to-digital conversion. The input terminal of the radio frequency high-voltage signal processing circuit corresponds to the ablation electrode port C, and the output terminal of the radio frequency high-voltage signal processing circuit corresponds to the neutral electrode port D. The input terminal of the output power detection circuit corresponds to the excitation output port A, and the output terminal of the output power detection circuit corresponds to the signal return port B. The input terminal of the temperature detection circuit corresponds to the platinum resistance temperature sensor interface 1E, and the output terminal of the temperature detection circuit corresponds to the platinum resistance temperature sensor interface 2F.

[0011] like Figure 2 As shown, the radio frequency high-voltage signal processing circuit includes a high-voltage attenuation module, a waveform compensation module, a signal amplification module, and a differential-to-single-digital converter module that are connected in sequence; the output terminal of the differential-to-single-digital converter module is connected to the input terminal of the analog-to-digital converter module.

[0012] like Figure 3As shown, the high-voltage attenuation module includes a front-end high-voltage differential probe circuit and a back-end bias signal processing circuit. The high-voltage differential probe circuit includes an ablation electrode port C terminal U24 and a neutral electrode port D terminal U25. Between the ablation electrode port C terminal and the neutral electrode port D terminal, there are sequentially connected series of attenuation resistors A1 (R82), nine voltage divider resistors A2 (R95-R102), sampling resistors A3 (R39, R42), an adjustable resistor R0, sampling resistors B1 (R52, R59), nine voltage divider resistors B2 (R64, R65, R87-R93), and attenuation resistor B3 (R83). The bias signal processing circuit includes four sets of capacitor banks connected in parallel. The first capacitor bank P1 consists of two bias capacitors connected in series, C87 and C3. The circuit consists of seven capacitor banks. The first bank, P1, has its A terminal connected between voltage divider resistor A2 and sampling resistor A3, and its B terminal connected between sampling resistor B1 and voltage divider resistor B2. The adjustable terminal of the adjustable resistor R0 is also connected to the first bank, P1. The second bank, P2 (C38, C86), and the third bank, P3 (C85, C88), each consist of two bias capacitors connected in series, with the same circuit connection as the first bank, P1. The fourth bank, P4, consists of two variable capacitors connected in series (C39, C89). The A terminal of the fourth bank, P4, is connected between voltage divider resistor A2 and sampling resistor A3, and its B terminal is connected between sampling resistor B1 and voltage divider resistor B2. The rear ends of the four parallel capacitor banks are grounded. The A and B terminals of the fourth bank, P4, are the attenuated signal output terminals.

[0013] like Figure 3 As shown, it also includes a clamping control circuit, which includes four protection diodes. The positive terminal of the first protection diode D8 is connected to terminal A of the first capacitor group P1, and the negative terminal is connected to the power supply terminal. The positive terminal of the second protection diode D10 is connected to terminal B of the first capacitor group P1, and the negative terminal is connected to the power supply terminal. The negative terminal of the third protection diode D9 is connected between terminal A of the second capacitor group P2 and terminal A of the third capacitor group P3, and the positive terminal is connected to the power supply terminal. The negative terminal of the fourth protection diode D11 is connected between terminal B of the third capacitor group P3 and terminal B of the fourth capacitor group P4, and the positive terminal is connected to the power supply terminal.

[0014] like Figure 3 As shown, the waveform compensation module includes multiple compensation capacitors C0 (C91-C99), and a compensation capacitor C0 (i.e., C42, C43, C79-C83, C90) is connected in parallel with each voltage divider resistor A2 and each voltage divider resistor B2. The multiple compensation capacitors C0 constitute the waveform compensation module.

[0015] like Figure 4As shown, the signal amplification module includes a voltage follower composed of dual transport amplifiers, comprising two amplifying transistors V0. The collectors of the two amplifying transistors V0 are connected to the attenuated signal output terminal. A first feedback resistor R1 is connected in series between the emitter and base of each of the two amplifying transistors V0, and a first capacitor C1 is connected in parallel across the first feedback resistor R1. The bases of the two amplifying transistors V0 are connected to the input terminal of the differential-to-single-transformer module through an input resistor R2.

[0016] like Figure 4 As shown, the differential-to-single-transistor module includes a single-transistor transistor V1. The collector and emitter of the single-transistor transistor V1 are respectively connected to the input resistor R2. The base of the single-transistor transistor V1 outputs a digital signal through the output resistor R3. A third capacitor C3 is connected in parallel with the output resistor R3. The collector of the single-transistor transistor V1 is also grounded through the protection resistor R4. A second feedback resistor R5 is connected in series between the emitter and base of the single-transistor transistor V1. A second capacitor C2 is connected in parallel with the second feedback resistor R5.

[0017] The output power detection circuit uses a non-inductive standard resistor as the measurement load. When measuring power using the non-inductive standard resistor method, an analog load resistor is selected, and the load resistance is adjusted using a relay. The power is then calculated using Formula 1. (1) In the formula, U is the radio frequency signal voltage; R is the resistance value of a non-inductive standard resistor; t is the duration of the radio frequency signal; To achieve power temperature measurement and detection of different human tissues in radiofrequency ablation equipment.

[0018] The temperature detection circuit uses a platinum resistance thermometer R. t As a temperature calibration sensor, the temperature head of the temperature calibration sensor is placed on the same plane as the top of the temperature sensing element of the radiofrequency ablation device and bound and fixed. It is then placed vertically in a constant temperature bath. Combined with a proportional source elimination circuit, the problem of fluctuation in the output voltage signal of the platinum resistance thermometer caused by the instability of the excitation source is eliminated. By utilizing the uniform temperature field of the constant temperature bath, the performance of the temperature sensor of the radiofrequency ablation device can be calibrated more accurately.

[0019] The proportional source elimination circuit includes an ADS1274 sampling processor, and the differential input port 1 of the ADS1274 sampling processor is connected to a platinum resistance thermometer R. t At both ends, differential input port 2 is connected to the two ends of reference resistor R1 to collect the voltage V2 across the platinum resistance and the voltage V1 across the reference resistor, respectively. Among them, the digital quantities V1 and V2 can be determined by equations 2 and 3, respectively.

[0020] (2) (3) Dividing the sum by the sum yields equation 4. (4) As can be seen from the above formula, the resistance value of the platinum resistance is only related to the differential signal channels 1 and 2 of the ADS1274 and the reference resistor R1, and its anti-interference capability is very strong.

[0021] 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.

[0022] The radiofrequency ablation equipment calibration device is a testing and calibration standard for completing radiofrequency ablation quality control. It utilizes highly integrated sensing technologies such as high-voltage differential detection, high-frequency non-inductive load, time-frequency synchronization, and impedance detection to detect key ablation parameters. The device can simulate human body impedance, allowing the radiofrequency energy output from the ablation equipment to be directly applied to the measurement system through surgical electrodes. The device incorporates sensing circuits for high-voltage attenuation, temperature, time, and impedance detection. The sensor output electrical signals are amplified and acquired by analog-to-digital signal amplification circuits, then converted to digital signals and transmitted to a microprocessor. Data processing software calculates the measured values ​​of parameters such as ablation power, impedance, frequency, temperature, and time, and finally displays the measurement results on a human-machine interface. Figure 1 As shown.

[0023] The calibrated radiofrequency ablation equipment typically has multiple power output modes, such as coagulation mode, bipolar mode, and shearing mode. The power output range varies for each mode. Referring to relevant domestic industry standards, the power requirement is set to no more than ±2W or ±20% of the nominal value (whichever is greater). By connecting a rated load resistor and a high-frequency power measurement system to the output circuit of the radiofrequency ablation equipment, adjusting the output power setting, and activating the equipment in simulated operation, the actual output power can be measured using a high-frequency power meter to calculate the output power error of the radiofrequency ablation equipment.

[0024] Typical radio frequency ablation equipment outputs energy from tens to hundreds of watts, corresponding to radio frequency signal voltage amplitudes ranging from tens to thousands of volts. Measuring high-voltage radio frequency signals requires a high-voltage differential probe circuit to divide the high-voltage signal to a voltage of (0-3.3)V that the analog-to-digital converter can normally input. The circuit's common-mode rejection requirement is as high as possible to cope with power frequency interference. At the same time, it is necessary to solve high-frequency signal distortion, reduce operating noise, optimize the operational amplifier feedback loop, and eliminate the oscillation problem of negative input.

[0025] The specific operation is as follows: Connect the ablation electrode port C and the neutral electrode port D to the device being calibrated via a connecting cable. At this time, calibrate the output power of the radiofrequency ablation device being calibrated. The high-voltage attenuation module power supply is set to 4.8V-5.5V, with an input bandwidth greater than 10MHz, and the packaged 1206 resistor has a withstand voltage of 200V. The radiofrequency ablation signal is input from ports U24 and U25, with two 1k attenuation resistors immediately following each port to increase the input impedance, reduce overshoot waveform, and make the square wave closer to a square wave. Figure 3 As shown, multiple resistors connected in series are used to attenuate the RF high-voltage signal, providing a 1000-fold attenuation capability. Each voltage divider resistor is connected in parallel with a phase compensation capacitor C0. Because the accuracy of the voltage divider resistors cannot fully meet the common-mode rejection requirements of the operational amplifier, an adjustable resistor R0 is used for fine-tuning to match the common-mode rejection requirements. Furthermore, since the operational amplifier output rails may be offset, a rail bias signal processing circuit needs to be added after the voltage divider. Finally, a protection diode is added for clamping control to prevent large voltage surges to the operational amplifier from damaging the system.

[0026] like Figure 3 As shown, the high-voltage attenuator uses nine 1MΩ voltage divider resistors and an 8000kΩ sampling resistor in series to achieve an attenuation of approximately 1100 times. For convenience, 7500Ω and 400Ω resistors are selected as sampling resistors, and a 200Ω adjustable potentiometer is also included to balance the ablation signal chain impedance. To prevent reflection and oscillation of the ablation signal, impedance matching between the attenuation voltage divider resistors and the sampling resistors is required. The RF attenuation circuit has its input impedance, which is a characteristic impedance. Besides the resistor's own impedance, it also includes parasitic capacitive and inductive reactance. Because the attenuator circuit introduces an additional load, the RF signal, after being connected to the attenuation measurement circuit, will have its energy absorbed by the parasitic impedance, affecting the measurement accuracy. Therefore, the impedance matching between the attenuation resistor and the sampling resistor must be considered. When the attenuation circuit is connected to DC and lower frequency signals, the attenuation resistor plays a dominant role. However, when the frequency exceeds 100kHz, the capacitive load effect of the capacitor becomes significant. The equivalent circuit for attenuation and sampling at high frequencies is as follows: Figure 6 As shown; When the attenuation voltage divider is impedance matched with the sampling resistor, the requirement of equation (5) must be met. and It is the capacitive reactance of the matching resistor. The capacitance value needs to be calculated according to formula (6) when selecting a capacitor.

[0027] (5) (6) In the formula, It is a voltage divider resistor; It is a sampling resistor; C is the matching capacitor. It is the capacitive reactance of the matching capacitor.

[0028] If the voltage divider resistor is too small, the charging current of the capacitor will be too large, resulting in an imbalance between the charging and discharging of the resistor and the capacitor. Equation 7 can be obtained from Equations 1 and 2. The voltage divider resistor and matching capacitor are selected according to Equation 3 for the attenuation circuit.

[0029] (7) The attenuated radio frequency ablation signal is output from the HV_IN+ and HV_IN- ports.

[0030] To ensure signal quality is not affected by impedance mismatch during subsequent transmission, preventing reflection or attenuation, a voltage follower consisting of dual operational amplifiers is required at the back end. This design features high input impedance and low output impedance, acting as a buffer between circuit stages, isolating attenuation and signal acquisition circuits, protecting the front-end circuit from interference from the rear-end circuit, and synchronously converting the differential signal to a single-ended signal to meet the input requirements of the analog-to-digital converter. The attenuated signal processing follows... Figure 4 As shown, the LT1222-based follower, with an 800pF capacitor connected in parallel across the feedback resistor, can achieve phase compensation and prevent self-oscillation, thus improving the circuit's linearity, stability, and anti-interference capability.

[0031] The differential signal output from the RF limiter after passing through a voltage follower already possesses the characteristics of high input impedance and low output impedance. Then, it passes through a differential-to-single-ended circuit centered around the LT1222, converting the differential signal into a single-ended signal that can be input to an analog-to-digital converter interface. Figure 5 Based on the principles of virtual short and virtual end of operational amplifiers, Equation 8 is used to calculate the magnitude of a single-ended signal.

[0032] (8) If the input resistor R2 and the feedback resistor are both selected with the same resistance value, Equation 7 can be simplified to Equation 9, which converts the differential signal into a single-ended signal.

[0033] (9) When performing output power detection, connect the excitation output port A and signal return port B on the device to the calibrated equipment. The output power detection circuit uses a non-inductive standard resistor as the measurement load. When measuring power using the non-inductive standard resistor method, select an analog load resistor with good frequency response, good stability, and low temperature drift. Adjust the load resistance value with a relay and use Formula 1 to obtain the power. This achieves the problem of power temperature measurement of different human tissues in radiofrequency ablation equipment. (1) In the formula, U is the radio frequency signal voltage; R is the resistance value of a standard resistor; t is the duration of the radio frequency signal.

[0034] During treatment, temperature is a key factor affecting the degree and extent of tissue necrosis. When the temperature is below a certain threshold, satisfactory treatment results may not be achieved; conversely, excessively high temperatures can lead to severe damage such as tissue carbonization and vaporization. Therefore, real-time monitoring of the temperature changes in the treatment area ensures that ablation treatment is performed within the appropriate temperature range, thereby achieving the best therapeutic effect.

[0035] When performing temperature calibration, the temperature detection circuit uses a platinum resistance thermometer (Rt) as the temperature calibration sensor. The platinum resistance temperature sensor interface 1E and platinum resistance temperature sensor interface 2F on the device are connected to the device being calibrated. The temperature sensing head of the temperature calibration sensor is placed on the same plane as the top of the temperature sensing element of the radiofrequency ablation device and bound and fixed. It is then placed vertically in the constant temperature bath. Combined with the proportional source elimination circuit, the problem of fluctuation in the output voltage signal of the platinum resistance thermometer caused by the instability of the excitation source is eliminated. By utilizing the uniform temperature field of the constant temperature bath, the performance of the temperature sensor of the radiofrequency ablation device is calibrated more accurately.

[0036] A platinum resistance thermometer (PTT) with high temperature measurement accuracy is used as the temperature sensor in the main unit. Since the PTT requires approximately 1mA of current to drive a small millivolt-level voltage signal, the device utilizes the high-resolution characteristics of the ADS1274 and a proportional source suppression circuit to eliminate fluctuations in the PTT output voltage signal caused by an unstable excitation source. The temperature measurement system built using the proportional source suppression method for processing the PTT signal is as follows: Figure 5 As shown. The proportional source elimination circuit includes an ADS1274 sampling processor, and the differential input port 1 of the ADS1274 sampling processor is connected to a platinum resistance resistor R. t At both ends, differential input port 2 is connected to the two ends of reference resistor R1 to collect the voltage V2 across the platinum resistance and the voltage V1 across the reference resistor, respectively. A 3.3V voltage signal is applied to the platinum resistance R. t and resistor R1, then respectively R t The voltages V1 and V2 across R1 are connected to the differential input ports 1 and 2 of the ADS1274, respectively.

[0037] Among them, the digital quantities V1 and V2 can be determined by equations 2 and 3, respectively.

[0038] (2) (3) Dividing the sum by the sum yields equation 4. (4) As shown in the above formula, the resistance value of the platinum resistance thermometer is only related to the differential signal channels 1 and 2 of the ADS1274 and the reference resistor R1, exhibiting very strong anti-interference capability. The maximum permissible error of the measurement results from this circuit is less than ±0.05℃, enabling accurate measurement of the temperature detection probe of the radiofrequency ablation device.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A calibration device for radiofrequency ablation equipment, characterized in that: The device includes a housing, an integrated circuit panel inside the housing, an operation display screen on the front of the housing, and six connection ports: an excitation output port, a signal return port, an ablation electrode port, a neutral electrode port, a platinum resistance temperature sensor interface 1, and a platinum resistance temperature sensor interface 2. An exhaust fan is located on the back of the housing. The integrated circuit panel is mainly used for processing radio frequency ablation quality control data and includes a central processing unit (CPU), an analog-to-digital converter (ADC), a display module, a timing module, a radio frequency high-voltage signal processing circuit, an output power detection circuit, and a temperature detection circuit. The signal input terminal of the CPU is connected to the signal output terminal of the ADC, and the first signal transmission terminal of the CPU is connected to the display screen. The display module and the second signal transmission terminal of the central processing unit are connected to the time module; the signal transmission terminals of the radio frequency high voltage signal processing circuit, the output power detection circuit and the temperature detection circuit are all connected to the analog-to-digital conversion module, and are sent to the central processing unit after analog-to-digital conversion; the input terminal of the radio frequency high voltage signal processing circuit corresponds to the ablation electrode port, and the output terminal of the radio frequency high voltage signal processing circuit corresponds to the neutral electrode port; the input terminal of the output power detection circuit corresponds to the excitation output port, and the output terminal of the output power detection circuit corresponds to the signal return port; the input terminal of the temperature detection circuit corresponds to the platinum resistance temperature sensor interface 1, and the output terminal of the temperature detection circuit corresponds to the platinum resistance temperature sensor interface 2.

2. The radiofrequency ablation equipment calibration device according to claim 1, characterized in that: The radio frequency high-voltage signal processing circuit includes a high-voltage attenuation module, a waveform compensation module, a signal amplification module, and a differential-to-single-digital converter module that are connected in sequence; the output of the differential-to-single-digital converter module is connected to the input of the analog-to-digital converter module.

3. The radiofrequency ablation equipment calibration device according to claim 2, characterized in that: The high-voltage attenuation module includes a front-end high-voltage differential probe circuit and a back-end bias signal processing circuit. The high-voltage differential probe circuit includes an ablation electrode port terminal and a neutral electrode port terminal. Between the ablation electrode port terminal and the neutral electrode port terminal, there are sequentially connected in series attenuation resistor A, nine voltage divider resistors A, a sampling resistor A, an adjustable resistor, a sampling resistor B, nine voltage divider resistors B, and an attenuation resistor B. The bias signal processing circuit includes four sets of capacitor banks connected in parallel. The first set of capacitor banks consists of two bias capacitors connected in series. Terminal A of the first set of capacitor banks is connected to the voltage divider resistor A. The circuit consists of two capacitor banks: a first capacitor bank and a second capacitor bank. The first capacitor bank consists of two variable capacitors connected in series. The second and third capacitor banks are each composed of two bias capacitors connected in series, and their circuit connections are identical to those of the first capacitor bank. The fourth capacitor bank consists of two variable capacitors connected in series. The first capacitor bank is connected at terminal A between the voltage divider resistor A and the sampling resistor A, and at terminal B between the sampling resistor B and the voltage divider resistor B. The rear ends of the four parallel capacitor banks are grounded. Terminals A and B of the fourth capacitor bank are the attenuated signal output terminals.

4. The radiofrequency ablation equipment calibration device according to claim 3, characterized in that: It also includes a clamping control circuit, which includes four protection diodes. The positive terminal of the first protection diode is connected to terminal A of the first capacitor group, and the negative terminal is connected to the power supply terminal. The positive terminal of the second protection diode is connected to terminal B of the first capacitor group, and the negative terminal is connected to the power supply terminal. The negative terminal of the third protection diode is connected between terminals A of the second and third capacitor groups, and the positive terminal is connected to the power supply terminal. The negative terminal of the fourth protection diode is connected between terminals B of the third and fourth capacitor groups, and the positive terminal is connected to the power supply terminal.

5. The radiofrequency ablation device calibration apparatus according to claim 2, characterized in that: The waveform compensation module includes multiple compensation capacitors. Each voltage divider resistor A and each voltage divider resistor B is connected in parallel with a compensation capacitor, and the multiple compensation capacitors constitute the waveform compensation module.

6. The radiofrequency ablation device calibration apparatus according to claim 5, characterized in that: The signal amplification module includes a voltage follower composed of dual transport amplifiers, comprising two amplifying transistors. The collectors of the two amplifying transistors are connected to the attenuated signal output terminal. A first feedback resistor is connected in series between the emitter and base of each of the two amplifying transistors, and a first capacitor is connected in parallel across the first feedback resistor. The bases of the two amplifying transistors are connected to the input terminal of the differential-to-single-transformer module through an input resistor.

7. The radiofrequency ablation device calibration apparatus according to claim 6, characterized in that: The differential-to-single-transistor module includes a single-transistor transistor. The collector and emitter of the single-transistor transistor are connected to the input resistor, and the base of the single-transistor transistor outputs a digital signal through the output resistor. A third capacitor is connected in parallel with the output resistor. The collector of the single-transistor transistor is also grounded through a protection resistor. A second feedback resistor is connected in series between the emitter and base of the single-transistor transistor, and a second capacitor is connected in parallel with the second feedback resistor.

8. The radiofrequency ablation equipment calibration device according to claim 1, characterized in that: The output power detection circuit uses a non-inductive standard resistor as the measurement load. When measuring power using the non-inductive standard resistor method, an analog load resistor is selected, and the load resistance is adjusted using a relay. The power is then calculated using Formula 1. （1） In the formula, U is the radio frequency signal voltage; R is the resistance value of a non-inductive standard resistor; t is the duration of the radio frequency signal; To achieve power temperature measurement and detection of different human tissues in radiofrequency ablation equipment.

9. The radiofrequency ablation equipment calibration device according to claim 1, characterized in that: The temperature detection circuit uses a platinum resistance thermometer R. t As a temperature calibration sensor, the temperature head of the temperature calibration sensor is placed on the same plane as the top of the temperature sensing element of the radiofrequency ablation device and bound and fixed. It is then placed vertically in a constant temperature bath. Combined with a proportional source elimination circuit, the problem of fluctuation in the output voltage signal of the platinum resistance thermometer caused by the instability of the excitation source is eliminated. By utilizing the uniform temperature field of the constant temperature bath, the performance of the temperature sensor of the radiofrequency ablation device can be calibrated more accurately.

10. The radiofrequency ablation device calibration apparatus according to claim 9, characterized in that: The proportional source elimination circuit includes an ADS1274 sampling processor, and the differential input port 1 of the ADS1274 sampling processor is connected to a platinum resistance resistor R. t At both ends, differential input port 2 is connected to the two ends of reference resistor R1 to collect the voltage V2 across the platinum resistance and the voltage V1 across the reference resistor, respectively. Among them, the digital quantities V1 and V2 can be determined by equations 2 and 3, respectively. (2) (3) Dividing the sum by the sum yields equation 4. (4) As can be seen from the above formula, the resistance value of the platinum resistance is only related to the differential signal channels 1 and 2 of the ADS1274 and the reference resistor R1, and has strong anti-interference ability.

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