Full-automatic measuring system for leakage current of high-frequency electrotome

Abstract

The invention discloses a full-automatic measuring system for leakage current of a high-frequency electrotome, and belongs to the field of leakage current detection. According to the system, information data of high-frequency electrotome set power, effective wire length, effective wire cross sectional area, working voltage and effective electrode resistance are collected through a set calibration value collection module; putting the acquired information data into a data caching module for caching, so that a data processing module can call data from the data caching module at any time for processing; and the data processing module calls the data from the data caching module, processes the data and obtains the magnitude of the leakage current. According to the invention, the magnitude and type of the leakage current can be measured in real time. And when the leakage current is detected and measured to be abnormal, the leakage current can be suppressed through a control circuit or in a mode of regulating and controlling the working voltage of the high-frequency electrotome equipment, so that the situation that the abnormal leakage current hurts a human body is avoided.

Description

Technical Field

[0001] The invention relates to leakage current detection, in particular to a full-automatic measurement system for leakage current of a high-frequency electric knife. Background Art

[0002] A high-frequency electric knife is an electrosurgical instrument that replaces a mechanical scalpel for tissue cutting. It heats the tissue when the high-frequency high-voltage current generated by the effective electrode tip contacts the body, achieves separation and coagulation of the body tissue, and thus achieves the purpose of cutting and hemostasis. It is one of the most important surgical instruments in surgical operations. Since the high-frequency electric knife uses high-frequency current to work, in order to ensure the safety of the patient during use, the leakage current of the high-frequency electric knife is usually monitored and measured in real time. The prior art (CN114280501A) provides a high-frequency leakage detection system for a high-frequency electric knife, which obtains the value of the first current output from the high-frequency energy generator to the first electrode through a first current detection module, and then obtains the value of the second current returned from the second electrode to the high-frequency energy generator through a second current detection module, wherein the second current is obtained after the first current passes through the object, and finally the value of the leakage current is obtained according to the difference between the value of the first current and the value of the second current, so that the high-frequency electric knife can monitor the high-frequency leakage current in real time during operation, thereby improving the safety and reliability of the operation. However, although the existing high-frequency electrosurgical unit leakage current measurement system can realize real-time monitoring and measurement of leakage current, when the leakage current is abnormal, it is unable to handle the abnormal leakage current in time, which may easily cause harm to the human body. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a fully automatic measurement system for high-frequency electrosurgical unit leakage current; to solve the problem that the current leakage current measurement system cannot handle abnormal leakage current in a timely manner.

[0004] Technical solution: A fully automatic measurement system for high-frequency electrosurgical unit leakage current, the system comprising: The set calibration value acquisition module is used to collect high-frequency electric knife set power, effective wire length, effective wire cross-sectional area, working voltage and effective electrode resistance information data; The data cache module is used to cache the information data collected by the set calibration value acquisition module, so that the data processing module can retrieve data from the data cache module for processing at any time; The monitoring module is used to monitor the frequency of leakage current in real time; The data processing module is used to retrieve data from the data cache module and process the data; specifically: The leakage current power is obtained according to the set power, working voltage, effective wire length and effective wire cross-sectional area of ​​the high-frequency electric knife, and the leakage current size is obtained according to the leakage current power and working voltage; at the same time, according to the real-time frequency of the leakage current monitored by the monitoring module, it is determined whether the leakage current is a high-frequency leakage current or a low-frequency leakage current; The analysis and judgment module is used to analyze and judge the results obtained by the data processing module, so as to obtain the analysis and judgment results; specifically: The leakage current type determined by the data processing module and the leakage current size obtained by the data processing module are compared with the preset threshold value to determine whether the leakage current is abnormal; the leakage current type, leakage current size and whether an abnormal result occurs are fed back through the result feedback module; when the leakage current is abnormal, the abnormal alarm module alarms; at the same time, the action execution module suppresses the leakage current through the control circuit.

[0005] Preferably, the data processing module obtains the magnitude of the leakage current according to the set power, working voltage, effective wire length and effective wire cross-sectional area of ​​the high-frequency electric knife: in, I leak is the leakage current size, P o The power set for the high-frequency electrosurgical unit, U is the working voltage of the high-frequency electrosurgical unit, r is the effective conductor resistivity, L , S are the length and cross-sectional area of ​​the effective conductor respectively, R e is the effective electrode resistance.

[0006] Preferably, when the monitoring module determines the type of leakage current, it detects the magnetic field generated by the leakage current through a 3D Hall sensor, and obtains the frequency of the leakage current through the frequency of the generated Hall voltage change, and then obtains whether the leakage current is a high-frequency leakage current or a low-frequency leakage current based on the frequency of the leakage current.

[0007] Preferably, the control circuit is composed of a sampling resistor, an operational amplifier, a comparator and a MOS tube; wherein there are two sampling resistors, and the resistance values ​​of the two sampling resistors are the same.

[0008] Preferably, two sampling resistors are connected in series on both sides of the load, respectively, and are denoted as R1 and R2; the non-inverting input of the op amp is connected to the node between R1 and the load, the inverting input is connected to the node between R2 and the load, and the output is connected to the non-inverting input of the comparator; the non-inverting input of the comparator receives the amplified signal of the op amp, the inverting input is connected to a preset threshold voltage, and the output drives the gate of the MOS tube; the gate of the MOS tube is controlled by the output signal of the comparator, the drain is connected in series on the abnormal path of the leakage current, and the source is grounded.

[0009] Preferably, an optical coupler is further provided between the comparator and the MOS tube to isolate the control signal from the high-voltage main circuit.

[0010] Preferably, when the leakage current is abnormal, the action execution module can also adjust the working voltage of the high-frequency electric knife to suppress the leakage current, specifically: in, D.U. is the voltage regulation value, I leak is the difference between the high-frequency leakage current and the safety threshold, P o The power set for the high-frequency electrosurgical unit, r is the effective conductor resistivity, L , S are the length and cross-sectional area of ​​the effective conductor respectively, R e is the effective electrode resistance.

[0011] Preferably, the feedback module can feed back the leakage current type determined by the monitoring module and the leakage current size obtained by the data processing module to the display module of the high-frequency electrosurgical device for display; and when the leakage current is abnormal, the abnormal alarm module will control the display module of the high-frequency electrosurgical device to flash to serve as an alarm.

[0012] Beneficial effects: The present invention deploys the system on the working path of the high-frequency electric knife, which enables the high-frequency electric knife to measure and monitor the leakage current in real time during operation, and can detect in real time whether the leakage current is high-frequency leakage current or low-frequency leakage current, and display the measurement and monitoring results on the display of the high-frequency electric knife device, so that medical staff can connect to the working status of the high-frequency electric knife in real time. And when the leakage current is detected to be abnormal, the leakage current can be suppressed by controlling the circuit or adjusting the working voltage of the high-frequency electric knife device to avoid the abnormal leakage current causing harm to the human body. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a system flow chart.

[0014] Figure 2It is a schematic diagram of the system architecture. DETAILED DESCRIPTION

[0015] In order to make the technical solution of the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. Example 1

[0016] The safety threshold of the high-frequency leakage current is set to 150mA. If the high-frequency leakage current is ≤150mA, the high-frequency leakage current is judged to be a safe leakage current. Otherwise, it is judged to be an abnormal high-frequency leakage current.

[0017] The safety threshold of the low-frequency leakage current is set to 0.01mA. If the low-frequency leakage current is ≤0.01mA, the low-frequency leakage current is judged to be a safe leakage current. Otherwise, it is judged to be an abnormal low-frequency leakage current.

[0018] like Figure 1 , 2 As shown, the fully automatic measurement system for the leakage current of the high-frequency electrosurgical knife is deployed on the working path of the high-frequency electrosurgical knife. The system collects the effective wire length, effective wire cross-sectional area and effective electrode resistance information data built into the system by setting the calibration value acquisition module, and at the same time collects the high-frequency electrosurgical knife set power and working voltage monitored by the power sensor and voltage sensor. The collected data will be put into the data cache module for data processing and retrieval. When the data processing module processes the data, it first follows the law of conservation of energy: in, P o The power set for the high-frequency electrosurgical unit, P ef is the effective power at the working electrode, P l is the power of the leakage current.

[0019] in: U is the working voltage of the high-frequency electrosurgical unit, r is the effective conductor resistivity, L , S are the length and cross-sectional area of ​​the effective conductor respectively, R e is the effective electrode resistance.

[0020] Then, the power of the leakage current can be obtained P l : in, R leak is the leakage current path resistance. Then according to I=U / R, the leakage current can be obtained I leak: When measuring leakage current I leak At the same time, the monitoring module detects the changing magnetic field generated by the leakage current through the 3D Hall sensor. At this time, the changing magnetic field generated by the leakage current will cause the Hall voltage to change inside the 3D Hall sensor, and the frequency of the Hall voltage can be obtained. Since the frequency of the Hall voltage is equal to the leakage current frequency, the leakage current frequency can be obtained through the Hall voltage frequency. According to the leakage current frequency obtained, it can be determined whether the current leakage current is a high-frequency leakage current or a low-frequency leakage current. (High-frequency leakage current 0.3~5 MHz, low-frequency leakage current 50~60 Hz). Then the result feedback module will feed back the type and size of the leakage current to the display of the high-frequency electrosurgical device for display, so that medical staff can understand the operating status of the Lu'anjie high-frequency electrosurgical device in real time.

[0021] Then the analysis and judgment module compares the type and size of the current leakage current with the preset safety threshold. If the measured leakage current frequency is 0.5MHz and the current size is 170mA, the leakage current is a high-frequency leakage current, 170mA>150mA, so the high-frequency leakage current is an abnormal leakage current. If the measured leakage current frequency is 55Hz and the current size is 0.2mA, the leakage current is a low-frequency leakage current, 0.2mA>0.01mA, so the frequency leakage current is an abnormal leakage current. When the leakage current is judged to be an abnormal leakage current, the result feedback module will feed back the judgment result to the abnormal alarm module, and the abnormal alarm module will control the high-frequency electrosurgical device display to flash an alarm.

[0022] At the same time, the action execution module will suppress the leakage current through the control current composed of two sampling resistors (both with a resistance of 1 ohm, and low resistance reduces voltage drop), op amp, comparator and MOS tube. The two sampling resistors are connected in series on both sides of the load, respectively, denoted as R1 and R2; the op amp LM358 (Gain=1000) has its non-inverting input connected to the node between R1 and the load, its reverse input connected to the node between R2 and the load, and its output connected to the non-inverting input of the comparator; the comparator LM393 (Vth=0.01V) has its non-inverting input receiving the amplified signal of the op amp, its reverse input connected to the preset threshold voltage, and its output driving the gate of the MOS tube; the gate of the MOS tube IRF540N (Vds=100V) is controlled by the output signal of the comparator, its drain is connected in series to the abnormal path of the leakage current, and its source is grounded. When the leakage current measured above is a high-frequency leakage current of 170mA, the op amp LM358 amplifies ΔV=(170mA / 1000)×1Ω×Gain=0.17V, ΔV>Vth. The comparator outputs a high level and drives the optocoupler HCPL-817 between the comparator and the MOS tube. At this time, the MOS tube is turned off, cutting off the leakage current path. In this way, the system can quickly cut off the abnormal path when the leakage current exceeds the limit, while ensuring the normal flow of effective current. Example 2

[0023] Based on Example 1, when the measured leakage current is a high-frequency leakage current with a magnitude of 170 mA, the difference between the current high-frequency current and the safety threshold is I leak It is 170-150=20mA. According to: I leak = 0.02A, P o Set to 50W , r 1.7×10 -8 Ω·m, L=3m , S=0.5m 2 , R e =10Ω. Substituting the above parameters into the above formula, we can get: Then we can calculate D.U. Approximately equal to 22.26V. Then the action execution module reduces the current working voltage of the high-frequency electric knife by 22.26V, which can suppress the leakage current and ensure that the leakage current is within a safe range. If the working voltage of the high-frequency electric knife is reduced, according to P=U2 / R (U is the working voltage of the high-frequency electric knife after voltage reduction, and R is the sum of the effective wire resistance and the effective electrode resistance) to obtain the working power of the high-frequency electric knife is less than the normal working range of the high-frequency electric knife, then the leakage current is suppressed by the method in Example 1.

[0024] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A fully automatic measurement system for high-frequency electrosurgical unit leakage current, characterized in that: The system includes: The set calibration value acquisition module is used to collect high-frequency electric knife set power, effective wire length, effective wire cross-sectional area, working voltage and effective electrode resistance information data; The data cache module is used to cache the information data collected by the set calibration value acquisition module, so that the data processing module can retrieve data from the data cache module for processing at any time; The monitoring module is used to monitor the frequency of leakage current in real time; The data processing module is used to retrieve data from the data cache module and process the data; specifically: The leakage current power is obtained according to the set power, working voltage, effective wire length and effective wire cross-sectional area of ​​the high-frequency electric knife, and the leakage current size is obtained according to the leakage current power and working voltage; at the same time, according to the real-time frequency of the leakage current monitored by the monitoring module, it is determined whether the leakage current is a high-frequency leakage current or a low-frequency leakage current; The analysis and judgment module is used to analyze and judge the results obtained by the data processing module, so as to obtain the analysis and judgment results; specifically: The leakage current type determined by the data processing module and the leakage current size obtained by the data processing module are compared with the preset threshold value to determine whether the leakage current is abnormal; the leakage current type, leakage current size and whether an abnormal result occurs are fed back through the result feedback module; when the leakage current is abnormal, the abnormal alarm module alarms; at the same time, the action execution module suppresses the leakage current through the control circuit.

2. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 1, characterized in that: The data processing module obtains the leakage current according to the set power, working voltage, effective wire length and effective wire cross-sectional area of ​​the high-frequency electrosurgical unit: in, I leak is the leakage current size, P o The power set for the high-frequency electrosurgical unit, U is the working voltage of the high-frequency electrosurgical unit, ρ is the effective conductor resistivity, L , S are the length and cross-sectional area of ​​the effective conductor respectively, R e is the effective electrode resistance.

3. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 1, characterized in that: When the monitoring module determines the type of leakage current, it detects the magnetic field generated by the leakage current through the 3D Hall sensor, and obtains the frequency of the leakage current through the frequency of the generated Hall voltage change. Then, based on the frequency of the leakage current, it can be determined whether the leakage current is a high-frequency leakage current or a low-frequency leakage current.

4. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 1, characterized in that: The control circuit is composed of a sampling resistor, an operational amplifier, a comparator and a MOS tube; there are two sampling resistors, and the resistance values ​​of the two sampling resistors are the same.

5. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 4, characterized in that: Two sampling resistors are connected in series on both sides of the load, respectively denoted as R1 and R2; the op amp's non-inverting input is connected to the node between R1 and the load, the inverting input is connected to the node between R2 and the load, and the output is connected to the comparator's non-inverting input; the comparator's non-inverting input receives the amplified signal of the op amp, the inverting input is connected to a preset threshold voltage, and the output drives the gate of the MOS tube; The gate of the MOS tube is controlled by the output signal of the comparator, the drain is connected in series to the abnormal path of the leakage current, and the source is grounded.

6. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 5, characterized in that: An optical coupler is also provided between the comparator and the MOS tube to isolate the control signal from the high-voltage main circuit.

7. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 1, characterized in that: When the leakage current is abnormal, the action execution module can also adjust the working voltage of the high-frequency electric knife to suppress the leakage current, specifically: in, ΔU is the voltage regulation value, ΔI leak is the difference between the high-frequency leakage current and the safety threshold, P o The power set for the high-frequency electrosurgical unit, ρ is the effective conductor resistivity, L , S are the length and cross-sectional area of ​​the effective conductor respectively, R e is the effective electrode resistance.

8. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 1, characterized in that: The feedback module can feed back the leakage current type determined by the monitoring module and the leakage current size obtained by the data processing module to the display module of the high-frequency electrosurgical device for display; and when the leakage current is abnormal, the abnormal alarm module will control the display module of the high-frequency electrosurgical device to flash to serve as an alarm.

9. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 1, characterized in that: The monitoring module monitors the real-time frequency of the leakage current through a 3D Hall sensor.

10. The fully automatic measurement system for high-frequency electrosurgical unit leakage current according to claim 1, characterized in that: The effective wire length, effective wire cross-sectional area and effective electrode resistance information data are built into the system, and the high-frequency electrosurgical unit setting power and operating voltage are monitored by power sensors and voltage sensors.

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