A fully automatic measurement system for leakage current of high-frequency electrosurgical units

Abstract

The present invention discloses a fully automatic measurement system for leakage current of a high-frequency electric knife, belonging to the field of leakage current detection. The system collects information data of the high-frequency electric knife set power, effective wire length, effective wire cross-sectional area, working voltage and effective electrode resistance through a set calibration value acquisition module; the above-collected information data is placed in a data cache module for caching, so that the data processing module can retrieve data from the data cache module for processing at any time; the data processing module retrieves data from the data cache module, processes the data, and obtains the leakage current size. The present invention can not only measure the leakage current size and type in real time. Moreover, when an abnormal leakage current is detected and measured, the leakage current can be suppressed by controlling the circuit or regulating the working voltage of the high-frequency electric knife equipment to avoid the abnormal leakage current causing harm to the human body.

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 electrosurgical unit is an electrosurgical instrument that replaces mechanical scalpels for tissue cutting. It uses high-frequency, high-voltage current generated by the active electrode tip to heat tissue upon contact, separating and coagulating it, thereby achieving both cutting and hemostasis. It is a crucial surgical instrument in surgery. Because high-frequency electrosurgical units utilize high-frequency current to operate, real-time monitoring and measurement of leakage current are often required to ensure patient safety during use. Prior art (CN114280501A) provides a high-frequency leakage current detection system for high-frequency electrosurgical units. This system uses a first current detection module to detect the value of a first current output from a high-frequency energy generator to a first electrode. A second current detection module then detects the value of a second current returned from a second electrode to the high-frequency energy generator. The second current is obtained after the first current passes through the subject. Finally, the difference between the first and second current values ​​determines the leakage current. This system enables real-time monitoring of high-frequency leakage current during operation, improving surgical safety and reliability. However, although the existing high-frequency electrosurgical unit leakage current measurement system can realize real-time monitoring and measurement of leakage current, it is unable to promptly handle abnormal leakage current when the leakage current is abnormal, which can 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 includes:

[0005] The calibration value acquisition module is used to collect information data on the high-frequency electrosurgical unit's set power, effective wire length, effective wire cross-sectional area, working voltage, and effective electrode resistance;

[0006] 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 the data from the data cache module for processing at any time;

[0007] The monitoring module is used to monitor the frequency of leakage current in real time;

[0008] The data processing module is used to retrieve data from the data cache module and process the data; specifically:

[0009] The leakage current power is obtained based on the set power, operating voltage, effective wire length, and effective wire cross-sectional area of ​​the high-frequency electrosurgical unit. The leakage current magnitude is then obtained based on the leakage current power and operating voltage. Furthermore, the real-time frequency of the leakage current detected by the monitoring module is used to determine whether the leakage current is high-frequency leakage current or low-frequency leakage current.

[0010] The analysis and judgment module is used to analyze and judge the results obtained by the data processing module, thereby obtaining the analysis and judgment results; specifically:

[0011] 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 issues an alarm; at the same time, the action execution module suppresses the leakage current through the control circuit.

[0012] Preferably, 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:

[0013] in, I leak is the leakage current, 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, R e is the effective electrode resistance.

[0014] 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.

[0015] 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.

[0016] Preferably, two sampling resistors are connected in series on both sides of the load, respectively 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.

[0017] 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.

[0018] 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:

[0019] 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, R e is the effective electrode resistance.

[0020] 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.

[0021] Beneficial Effects: The present invention deploys the system on the working path of a high-frequency electrosurgical unit, enabling real-time measurement and monitoring of leakage current during operation. It can also detect in real time whether the leakage current is high-frequency or low-frequency, and display the measurement and monitoring results on the display of the high-frequency electrosurgical unit, allowing medical personnel to monitor the working status of the high-frequency electrosurgical unit in real time. Furthermore, when an abnormal leakage current is detected, the leakage current can be suppressed by controlling the circuit or regulating the operating voltage of the high-frequency electrosurgical unit, preventing the abnormal leakage current from causing harm to the human body. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a system flow chart.

[0023] Figure 2 This is a schematic diagram of the system architecture. DETAILED DESCRIPTION

[0024] 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

[0025] 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.

[0026] The safety threshold of the low-frequency leakage current is set to 0.01 mA. If the low-frequency leakage current is ≤ 0.01 mA, 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.

[0027] like Figure 1 、 2 As shown in the figure, 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 through the calibration value acquisition module. At the same time, it collects the high-frequency electrosurgical knife set power and working voltage monitored by the power sensor and voltage sensor. The collected data will be placed in the data cache module for data processing and retrieval. When processing the data, the data processing module first follows the law of conservation of energy:

[0028] 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.

[0029] in:

[0030] 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, R e is the effective electrode resistance.

[0031] Then, the power of the leakage current can be obtained P l :

[0032] in, R leakis the leakage current path resistance. Then according to I=U / R, the leakage current can be obtained I leak :

[0033] When measuring leakage current I leak While monitoring the leakage current, the monitoring module uses a 3D Hall sensor to detect the changing magnetic field generated by the leakage current. This changing magnetic field generates a varying Hall voltage within the 3D Hall sensor, which then provides the frequency of the Hall voltage. Since the Hall voltage frequency is equal to the leakage current frequency, the leakage current frequency can be derived from the Hall voltage frequency. This frequency can be used to determine whether the leakage current is high-frequency or low-frequency (high-frequency leakage current ranges from 0.3 to 5 MHz, and low-frequency leakage current ranges from 50 to 60 Hz). The result feedback module then transmits the leakage current type and magnitude to the high-frequency electrosurgical device's display, allowing medical staff to monitor the Lu'anjie high-frequency electrosurgical device's operating status in real time.

[0034] The analysis and judgment module then compares the type and magnitude of the current leakage current with a pre-set safety threshold. If the measured leakage current frequency is 0.5MHz and the current magnitude is 170mA, the leakage current is a high-frequency leakage current, and 170mA is greater than 150mA, so the high-frequency leakage current is abnormal. If the measured leakage current frequency is 55Hz and the current magnitude is 0.2mA, the leakage current is a low-frequency leakage current, and 0.2mA is greater than 0.01mA, so the high-frequency leakage current is abnormal. Once the leakage current is determined to be abnormal, the result feedback module will feed back the judgment result to the abnormal alarm module, which will control the high-frequency electrosurgical device display to flash an alarm.

[0035] At the same time, the action execution module suppresses leakage current through a control circuit consisting of two sampling resistors (both 1 ohm, with lower resistance reducing voltage drop), an op amp, a comparator, and a MOSFET. The two sampling resistors are connected in series on either side of the load, designated R1 and R2. The non-inverting input of the LM358 op amp (Gain = 1000) 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 LM393 comparator (Vth = 0.01V) receives the amplified signal from the op amp, the inverting input is connected to a preset threshold voltage, and the output drives the gate of the MOSFET. The gate of the MOSFET IRF540N (Vds = 100V) is controlled by the comparator's output signal. Its drain is connected in series with the abnormal leakage current path, and its source is grounded. When the measured leakage current is high-frequency, at 170mA, the LM358 op amp amplifies the signal by ΔV = (170mA / 1000) × 1Ω × Gain = 0.17V, where ΔV > Vth. The comparator outputs a high level, driving the HCPL-817 optocoupler between the comparator and the MOSFET. This turns the MOSFET off, severing the leakage current path. This allows the system to quickly shut down the abnormal path when excessive leakage current is detected, while ensuring the flow of effective current. Example 2

[0036] Based on Example 1, when the measured leakage current is a high-frequency leakage current of 170 mA, the difference between the current high-frequency current and the safety threshold is I leak 170-150=20mA. According to:

[0037]

[0038] 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:

[0039]

[0040] Then we can calculate D.U.It is 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=U 2 / 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) is less than the normal working range of the high-frequency electric knife, the leakage current is suppressed by the method in Example 1.

[0041] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A fully automatic measurement system for high-frequency electrosurgical unit leakage current, characterized in that: The system includes: The calibration value acquisition module is used to collect information data on the high-frequency electric knife set power, effective wire length, effective wire cross-sectional area, working voltage and effective electrode resistance; 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 the 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 based on the set power, operating voltage, effective wire length, and effective wire cross-sectional area of ​​the high-frequency electrosurgical unit. The leakage current magnitude is then obtained based on the leakage current power and operating voltage. Furthermore, the real-time frequency of the leakage current detected by the monitoring module is used to determine whether the leakage current is high-frequency leakage current or low-frequency leakage current. The analysis and judgment module is used to analyze and judge the results obtained by the data processing module, thereby obtaining the analysis and judgment results; specifically: The leakage current type determined by the data processing module and the leakage current magnitude 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 magnitude, and whether an abnormal result is present are fed back through the result feedback module. When the leakage current is abnormal, the abnormal alarm module issues an alarm. At the same time, the action execution module suppresses the leakage current through the control circuit. 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, R e is the effective electrode resistance.

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, 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, 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, denoted as R1 and R2 respectively; 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 from 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 optocoupler 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: 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.

8. 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 leakage current through a 3D Hall sensor.

9. 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's set power and operating voltage are monitored by power sensors and voltage sensors.

Images