CN118766572A - A method for collecting and calibrating output feedback of high-frequency surgical equipment - Google Patents

Abstract

The invention discloses a method for collecting and calibrating output feedback of high-frequency operation equipment, which comprises the following steps: after the high-frequency operation equipment is powered on, reading the revised data from the nonvolatile memory; when the high-frequency operation equipment starts to output, feedback voltage Vn and current In which are digital quantities after analog-digital conversion are acquired In real time; the hf surgical device calculates the actual output voltage V and the output current I based on Vn, in and the calibrated parameters. The invention greatly improves the power output precision of the high-frequency operation equipment in a wide impedance range and improves the equipment adaptability.

Description

A method for collecting and calibrating output feedback of high-frequency surgical equipment

Technical Field

The present invention belongs to the technical field of medical device industry, and more specifically relates to a method for collecting and calibrating output feedback of high-frequency surgical equipment.

Background Art

High-frequency surgical equipment is a surgical instrument widely used in hospitals, including high-frequency electric knives, plasma scalpels, radiofrequency ablation equipment, etc.

The general power output signal characteristics of high-frequency surgical equipment are: frequency above 200K, power of tens to hundreds of watts, and waveform of continuous sine wave or modulated waveform. In order to achieve clinical applications, the control system of high-frequency surgical equipment needs to collect parameters such as output power and tissue impedance in real time to reasonably control the output energy and match different consumables and surgical procedures. To calculate power and impedance, it is necessary to collect the voltage and current signals fed back by the power circuit. The feedback voltage and current signals are the power output signals sensed by transformers or Hall sensors. The feedback signal waveform is consistent with the output power signal, but the amplitude is very small, which is easy to adjust and collect the back-end circuit of the low-voltage control system. The feedback signal and the output power signal have a proportional relationship. After the control system collects the feedback signal, it calculates the actual output voltage and current values according to the proportional relationship, and then performs further processing.

Due to the power topology, the ratio of the feedback signal to the actual output signal is not constant in all cases. In particular, it is greatly affected by the load impedance. In actual clinical practice, the tissue impedance at the point where the high-frequency equipment consumables act may vary from tens of ohms to thousands of ohms. The relevant special standards for high-frequency surgical equipment also stipulate that the power output accuracy or impedance accuracy under different loads (50Ω to 2000 ohms for monopolar and 10 ohms to 1000 ohms for bipolar) needs to be tested. Therefore, accurately calculating the feedback signal value under different loads is crucial for high-frequency surgical equipment and determines its basic performance.

In the process of implementing the present invention, the applicant discovered that the above-mentioned prior art has the following technical defects:

(1) The impedance range is narrow, and the output accuracy can only be guaranteed near the declared rated load. The output accuracy is significantly reduced at other impedances.

(2) Poor adaptability. Due to hardware differences between different devices, the output accuracy fluctuates greatly, which is not conducive to large-scale production.

Summary of the invention

Based on the above reasons, the present invention is committed to solving the above problems and aims to provide a method for collecting and calibrating the output feedback of high-frequency surgical equipment, which improves the power output accuracy and equipment adaptability of high-frequency surgical equipment within a wide impedance range. Specifically, in order to achieve the purpose of the present invention, the present invention intends to adopt the following technical solutions:

One aspect of the present invention relates to a method for collecting and calibrating output feedback of a high-frequency surgical device, which comprises the following steps:

After the high-frequency surgical device is powered on, the calibration data is read from the non-volatile memory and written into the array Cal[n][m], where n is the number of calibration points, and m is the number of calibration parameters. The array stores the calibration parameters Vc, Ic, Vd, and Id of each point, where Vc and Ic are the actual output voltage Vc and output current Ic pre-acquired under different impedances, and Vd and Id are the voltage Vd and current values Id synchronously obtained by the internal control system of the high-frequency surgical device through the ADC under different impedances, where Vd and Id are digital quantities after analog-to-digital conversion; where n is between 5 and 20, and m is a natural number greater than 4;

When the high-frequency surgical equipment starts to output, the feedback voltage Vn and current In are collected in real time. Vn and In are digital quantities after analog-to-digital conversion.

The high-frequency surgical equipment calculates the actual output voltage V and output current I according to Vn, In and the calibration parameters, which includes the following steps:

First, calculate F = Vn/In;

Secondly, compare the Vd/Id of all calibration points in F and Cal[n][m]. When Vd _(n) /Id _(n) >F>Vd _(n-1) /Id _(n-1) , calculate _δn =Vd _(n) /Id _(n) -Vd/Id and δn _-1 =Vd/Id-Vd _(n-1) /Id _(n-1) . When δn≥δn-1, select the n-1th point as the calibration point for calculation. When δ< _δn-1 , select the nth point as the calibration point for calculation.

Among them, the actual output V＝Vc _(n) * _Vn /Vd _(n) , I＝Ic _(n) *In/Id _(n) .

In a preferred embodiment of the present invention, the different impedances of the electrosurgical analyzer are between 10-2000.

In a preferred embodiment of the present invention, said n is 10-20.

In a preferred embodiment of the present invention, the calibration parameter Vn/In is stored in the non-volatile memory.

In a preferred embodiment of the present invention, the calibration tool comprises a high-frequency surgical device and an electrosurgical analyzer, wherein the electrosurgical analyzer can set impedance as a load of the high-frequency surgical device and return acquisition parameters.

In a preferred embodiment of the present invention, the high-frequency surgical device and the electrosurgical unit analyzer interact with each other via a serial port or a USB.

Beneficial Effects

The present invention provides a new feedback collection and calibration method. First, several resistance collection points are set as calibration loads. At each resistance value, the high-frequency surgical device outputs a signal excitation resistor with appropriate power, collects the original feedback signal, and records the output voltage and current signals at this time, and stores them in a non-volatile memory, so as to calibrate the reference parameters of each impedance point in the entire impedance range. During actual operation, the control system collects the feedback signal and compares it with the reference parameter, and obtains the accurate output value through conversion and calculation. The present invention greatly improves the power output accuracy of the high-frequency surgical device within a wide impedance range, and at the same time improves the adaptability of the device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of hardware connection of an embodiment of the present invention.

FIG2 is a schematic diagram of the revision process of the present invention.

FIG3 is a schematic diagram of a calculation conversion process according to an embodiment of the present invention.

DETAILED DESCRIPTION

In order to further understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Unless otherwise specified, the individual components involved in the embodiments of the present invention are commercially available products and can be purchased through commercial channels.

Example 1

The implementation of the scheme of the present invention includes two processes: load calibration and calculation conversion, and its hardware connection is shown in Figure 1. The calibration tool includes a high-frequency surgical device and an electrosurgical analyzer. The electrosurgical analyzer can set impedance as the load of the high-frequency surgical device and return acquisition parameters; the high-frequency surgical device and the electrosurgical analyzer interact through a serial port or USB.

The revision process is shown in Figure 2:

High-frequency surgical equipment sets the impedance R of the electrosurgical analyzer. The impedance is set according to the actual load range, and generally requires R to be in the range of 10-2000 ohms. Impedance selection does not need to be continuous, and usually n of 10-20 can meet the requirements.

High-frequency surgical equipment needs to output a certain power to excite the load impedance, which can be set to 30% to 50% of full power.

The high-frequency surgical equipment communicates with the electrosurgical knife analyzer to obtain the actual output voltage Vc and output current Ic. The internal control system of the high-frequency surgical equipment synchronously obtains the voltage Vd and current value Id through the ADC, where Vd and Id are digital quantities after analog-to-digital conversion.

The high-frequency surgical equipment stores Vc, Ic, Vd, and Id in a non-volatile memory chip as calibration parameters for that point.

If n resistance points are selected for calibration, the memory chip needs to provide at least 4Xn parameters' required space.

The calculation conversion process is shown in Figure 3:

After the high-frequency surgical equipment is powered on, the calibration data is read from the non-volatile memory and written into the array Cal[n][m], where n is the number of calibration points and m is the number of calibration parameters. The array stores the calibration parameters Vc, Ic, Vd, and Id of each point.

When the high-frequency surgical equipment starts to output, the feedback voltage Vn and current In are collected in real time. Vn and In are digital quantities after analog-to-digital conversion.

The high-frequency surgical equipment calculates the actual output values V and I based on Vn, In and calibration parameters:

Calculate F = Vn/In;

Compare F with the Vd/Id of all calibration points in Cal[n][m]. When Vd _(n) /Id _(n) >F>Vd _(n-1) /Id _(n-1) , calculate

_δn ＝Vd _(n) /Id _(n) -Vd/Id and δn _-1 ＝Vd/Id-Vd _(n-1) /Id _(n-1) . When δn≥δn-1, the n-1th point is selected as the calculation correction point. When δ< _δn-1 , the nth point is selected as the calculation correction point.

Actual output V = Vc _(n) * _Vn / Vd _(n) , I = Ic _(n) * In / Id _(n)

The above describes the preferred embodiments of the present invention, but it is not intended to limit the present invention. Those skilled in the art may make improvements and changes to the embodiments disclosed herein without departing from the scope and spirit of the present invention.

Claims (6)

1. A method for collecting and calibrating output feedback of high-frequency operation equipment comprises the following steps:

After the high-frequency operation equipment is electrified, reading the corrected data from a nonvolatile memory, writing the corrected data into an array Cal [ n ] [ m ], wherein n is the number of corrected points, m is the number of corrected parameters, and storing corrected parameters Vc, ic, vd, id of each point in the array, wherein Vc and Ic are actual output voltage Vc and output current Ic which are obtained in advance under different impedances, vd and Id are voltage Vd and current value Id which are obtained by an internal control system of the high-frequency operation equipment through ADC (analog-to-digital converter) under different impedances, and Vd and Id are digital quantities after analog-to-digital conversion; wherein n is a natural number between 5 and 20, and m is a natural number above 4;

When the high-frequency operation equipment starts to output, feedback voltage Vn and current In which are digital quantities after analog-digital conversion are acquired In real time;

The high frequency surgical device calculates an actual output voltage V and an output current I based on Vn, in and the correction parameters, comprising the steps of:

first, f=vn/In is calculated;

Secondly, comparing Vd/Id of all the correction points in F and Cal [ n ] [ m ], when Vd _(n)/Id_(n)>F>Vd_(n-1)/Id_(n-1), calculating delta _n＝Vd_(n)/Id_(n) -Vd/Id and delta _n-1＝Vd/Id-Vd_(n-1)/Id_(n-1), when delta n is more than or equal to delta n-1, selecting the n-1 point as the calculation correction point, and when delta is less than delta _n-1, selecting the n point as the calculation correction point;

Where the actual output v=vc _(n)*V_n/Vd_(n),I＝Ic_(n)*In/Id_(n).

2. The method of claim 1, wherein the electrotome analyzer has different impedances between 10-2000.

3. The method of claim 1, wherein n is 10-20.

4. The method of claim 1, wherein the non-volatile memory stores a collation parameter Vn/In.

5. The method of claim 1, wherein the revision tool comprises a high frequency surgical device, an electrotome analyzer, wherein the electrotome analyzer can set an impedance as a load of the high frequency surgical device and return the acquisition parameters.

6. The method of claim 5, wherein the high frequency surgical device and the electrotome analyzer interact via a serial port or USB.