Plasma surgical system and control method for rapid generation of plasma state

Abstract

The application provides a kind of fast generation plasma state plasma surgery system and control method, it solves the problem of plasma arc starting and slow arc reaction, including MCU module, MCU module is connected with switching power supply through PWM controller, MCU module is connected with high frequency power amplifier module through MOS drive module, switching power supply and high frequency power amplifier module are connected with the voltage division circuit connected with MCU module, high frequency power amplifier module and MCU module are connected with fault detection module, high frequency power amplifier module is connected with surgical electrode and is provided with voltage detection module and current detection module connected with MCU module between, surgical electrode is connected with MCU module.The application has the advantages of high safety, fast response rate and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of medical electrosurgical equipment, and particularly relates to a plasma operation system capable of quickly generating plasma and a control method. BACKGROUND

[0002] At present, the plasma operation equipment in the industry can realize plasma electric cutting and electric coagulation operation on human soft tissue in a physiological saline environment. The key core is how to quickly and smoothly cut the tissue while causing less thermal damage to the tissue when using the plasma arc to cut the tissue. The prior art does not have a related technology for quickly generating plasma arc, but only uses a power amplifier circuit to output a large power under low load impedance to realize ionization arc starting. In actual application, this technology only limits the maximum output power of the plasma arc starting stage, realizes protection of the equipment, reduces the maximum energy output to the patient, and protects the patient. Although this method can generate a plasma arc to a certain extent, the arc starting time is not fast enough, the arc starting difficulty is increased, and after the arc is started, the arc cannot quickly exit the arc starting state to the normal cutting state, thereby increasing the risk of tissue thermal damage. Especially when performing plasma electric cutting on the inner membrane surface of human tissue (such as the endometrium), if the surface is uneven, the cutting process is slow or cannot be maintained (when the electrode head slightly leaves the tissue during movement, the arc will be extinguished, and the arc cannot be quickly restarted after being extinguished), which will seriously affect the smoothness of cutting, bring great inconvenience to the doctor's operation, and affect the clinical effect.

[0003] In order to solve the problems in the prior art, people have made long-term exploration and proposed various solutions. For example, Chinese patent document discloses a plasma energy control switch circuit and a control system thereof [201911003169.1], which comprises a peak power control circuit, a single-chip microcomputer and a switch module used for being connected in series in a plasma energy control system circuit, wherein: the peak power control circuit is used for dynamically sampling and filtering the current of the plasma energy control system, and adjusting the amplification multiple of the generated voltage signal to adjust the peak power point, and then sending the voltage signal to the single-chip microcomputer; the single-chip microcomputer is used for receiving and processing the voltage signal sent by the peak power control circuit, and controlling the working period of the switch module according to the processed voltage signal, so that the output power of the plasma energy control system does not exceed the preset peak power and meets the preset power curve.

[0004] The above scheme solves the problem of generating a plasma arc to a certain extent, but the scheme still has many problems, such as slow arc starting and arc extinguishing. SUMMARY

[0005] The present application aims at the above-mentioned problems, and provides a plasma surgery system capable of quickly generating plasma state and having reasonable design and good cutting effect.

[0006] Another object of the present application is to provide a control method of the plasma surgery system capable of quickly generating plasma state and having fast response rate of arc striking and arc withdrawing.

[0007] To achieve the above-mentioned objects, the present application adopts the following technical scheme: a plasma surgery system capable of quickly generating plasma state, comprising an MCU module, the MCU module being connected with a switching power supply through a PWM controller, the MCU module being connected with a high-frequency power amplifier module through a MOS driving module, a voltage dividing circuit being connected between the switching power supply and the high-frequency power amplifier module and connected with the MCU module, a fault detection module being connected between the high-frequency power amplifier module and the MCU module, the high-frequency power amplifier module being connected with a surgery electrode and provided with a voltage detection module and a current detection module connected with the MCU module, and the surgery electrode being connected with the MCU module.

[0008] In the above-mentioned plasma surgery system capable of quickly generating plasma state, the MCU module is connected with a loudspeaker through a sound control module.

[0009] In the above-mentioned plasma surgery system capable of quickly generating plasma state, the MCU module is connected with a touch screen and a foot switch.

[0010] A control method of a plasma surgery system capable of quickly generating plasma state, comprising the following steps:

[0011] S1: when the foot switch and the surgery electrode are in a connected state, the MCU module performs real-time scanning on the state of the foot switch, when the cutting pedal of the foot switch is stepped on, the state change is detected by the MCU module, the running of the cutting mode is started, and a pretreatment mode is first entered;

[0012] S2: whether the pretreatment has an abnormality is judged, and if not, arc striking control is entered;

[0013] S3: whether the arc striking is successful is judged, and if so, a tissue cutting stage is entered;

[0014] S4: the system performs detection on the state of the foot switch, when the foot switch is released, all outputs are closed, and the cutting mode is exited; otherwise, the running of the tissue cutting stage is continued.

[0015] In the above-mentioned control method of the plasma surgery system capable of quickly generating plasma state, the pretreatment mode in step S1 comprises the following steps:

[0016] S11: The MCU module controls the switch power supply to output a preset VCT DC voltage through the DA module, and samples the VCT voltage through a voltage dividing circuit to determine whether the actually output VCT voltage is within the preset range;

[0017] S12: The high-frequency power amplifier is controlled to output through a complementary PWM signal, and the working state of the high-frequency power amplifier module is detected through a feedback circuit. After normal operation, the high-frequency voltage and high-frequency current output by the high-frequency power amplifier module are detected, and the current initial impedance R0 is calculated.

[0018] In the control method of the above-described plasma surgical system capable of rapidly generating plasma, when the initial impedance R0 in step S2 is less than a certain value, arc starting control is entered; if any step is abnormal, all outputs are directly turned off, and the operation of the cutting mode is ended.

[0019] In the control method of the above-described plasma surgical system capable of rapidly generating plasma, step S3 includes the following steps:

[0020] S31: The system controls the switch power supply to output a VCT voltage through the DA module, denoted as V vct1 ;

[0021] S32: The system detects the high-frequency voltage and high-frequency current output by the high-frequency power amplifier module, and calculates the current load impedance R1;

[0022] S33: The system increases the VCT voltage output, denoted as V vct2 ;

[0023] S34: After a delay of about 1 ms according to the above steps, a new load impedance R2 is obtained, and in this way, load impedances R n , are obtained. When the continuously obtained load impedances are all greater than R0, it is considered that the system ionizes and arcs successfully, and enters the tissue cutting stage.

[0024] In the control method of the above-described plasma surgical system capable of rapidly generating plasma, step S3 simultaneously performs the longest arc starting time counting when the arc starting success is judged. When the time overflows, the energy output is turned off, and after a delay, step S3 is re-entered to perform arc starting control.

[0025] In the control method of the above-described plasma surgical system capable of rapidly generating plasma, in the tissue cutting stage, the system output power is adjusted in real time according to the detected load impedance R m and load power P m . The adjustment algorithm adopts a double competition method, that is, the constant power and constant voltage modes are competed, the module corresponding to the smaller expected VCT voltage obtains a competitive advantage, and the switch power supply is controlled to output through the DA module.

[0026] In the control method of the plasma surgical system capable of quickly generating plasma state, the tissue cutting stage in step S3 is changed into a tissue coagulation stage, and the adjustment algorithm adopts a three-competition method, that is, an output constant current mode, an output constant power mode and an output constant voltage mode compete with each other, a module corresponding to a smaller expected VCT voltage has a competitive advantage, and the DA module controls the switch power supply output.

[0027] Compared with the prior art, the advantages of the application are as follows: the Na ions in the physiological saline solution are ionized by using a dynamic energy loading method, the plasma arc is started faster, the arc is difficult to extinguish during the cutting process, the cutting is more smooth, and the clinical performance is better; the disadvantages caused by the fixed energy loading method are avoided, the situation that the energy is insufficient due to too small loading energy setting and the plasma arc is difficult to start is prevented, the situation that too high loading energy setting causes too much energy to be instantaneously generated and the tissue is damaged by the heat is prevented, and the system use safety is improved. BRIEF DESCRIPTION OF DRAWINGS

[0028] Fig. 1 is a system principle diagram of the application;

[0029] Fig. 2 is a method flowchart of the application;

[0030] In the figure, MCU module 1, sound control module 11, loudspeaker 12, touch screen 13, foot switch 14, PWM controller 2, switch power supply 3, MOS drive module 4, high-frequency power amplifier module 5, voltage division circuit 6, fault detection module 7, surgical electrode 8, voltage detection module 81 and current detection module 82. DETAILED DESCRIPTION

[0031] The application will be further described in detail below in combination with the drawings and specific embodiments.

[0032] As Figs. 1-2As shown, a kind of plasma surgical system for quickly generating plasma state, high-frequency energy is generated by generator, and physiological saline solution is excited to form high-energy density plasma thin layer around surgical electrode, which is highly ionized, highly gasified plasma layer (50um-100um), the thin layer has enough energy to crush the organic molecular chain in tissue, so that the intermolecular separation is realized, and the volume of tissue is reduced, to achieve the purpose of cutting, coagulation hemostasis, realize the positioning separation of patient tissue. Including MCU module 1, MCU module 1 is connected with switching power supply 3 through PWM controller 2, MCU module 1 is connected with high-frequency power amplifier module 5 through MOS drive module 4, switching power supply 3 and high-frequency power amplifier module 5 are connected with voltage dividing circuit 6 connected with MCU module 1, high-frequency power amplifier module 5 and MCU module 1 are connected with fault detection module 7, high-frequency power amplifier module 5 is connected with surgical electrode 8 and is provided with voltage detection module 81 and current detection module 82 connected with MCU module 1 between them, surgical electrode 8 is connected with MCU module 1.

[0033] Net power supply AC220V is isolated by switching power supply 3 to output adjustable DC voltage (referred to as VCT), the VCT voltage is loaded into the high-frequency power amplifier module 5 composed of full-bridge topology structure, the high-frequency power amplifier module 5 is driven by the special MOS tube driving chip from the complementary PWM signal generated by MCU module 1, the high-voltage sinusoidal wave voltage output by high-frequency power amplifier module 5 is acted on the patient surgical site through surgical electrode 8, the Na ion in the surgical site under the environment of physiological saline is excited by high-frequency high voltage, and high-energy plasma thin layer is quickly generated at the front end of surgical electrode, to form plasma arc, the arc has a large amount of energy, and is acted on the lesion tissue, to crush the organic molecular chain in tissue, realize effective cutting of tissue, and coagulation hemostasis.

[0034] Specifically, MCU module 1 is connected with loudspeaker 12 through sound control module 11.

[0035] In-depth, MCU module 1 is connected with touch screen 13 and foot switch 14.

[0036] In this embodiment, the switching power supply 3 adopts full-bridge topology to realize the isolation output of VCT DC voltage, and the high-frequency power amplifier module 5 adopts full-bridge topology to realize the voltage output of high-frequency alternating sine wave. The key power transformer and power amplifier transformer are wound by EE55 magnetic core, the output inductance is wound by ferrosilicon aluminum magnetic ring, the high-voltage and high-current switching is realized by using high-power MOS tube (such as FDA24N50) in the circuit, the output voltage of the high-frequency power amplifier module 5 is sampled by using an isolation transformer (which can be wound by UF16 magnetic core), the current signal is converted into voltage by using a current transformer (such as PE-51688NL), the RMS chip is used to realize the conversion from alternating signal to direct current signal, the MCU module 1 adopts a general 32-bit ARM chip (such as STM32F407) which has AD sampling module and DA output module, and can also be externally connected with a special ADC chip and / or DAC chip, the output of the PWM controller 2 is realized by using the hardware PWM module in the MCU module 1, and the working frequency and phase difference between signals are set by software. The MCU module 1 has a built-in communication module to realize the communication with an external capacitive touch screen, the loudspeaker 12 adopts a general loudspeaker with 8 ohms and 2W, and the foot switch 14 is input to the MCU module 1 after being isolated by an optical coupler (such as TLP291) to realize the foot level sampling. By using the above circuit, the technology is easy to realize, the components are easy to obtain, the cost is low, and the performance is stable and reliable.

[0037] In actual operation, in order to ensure better plasma arc starting effect and cutting effect, the system collects the high-frequency voltage and high-frequency current loaded to the tissue in real time through the voltage detection module 81 and the current detection module 82, converts the effective value voltage collected into a digital signal through the built-in ADC chip of the MCU module 1, calculates the real-time impedance R and real-time power P loaded to the tissue by software operation, and the specific calculation is as follows:

[0038] R = V rms / I rms

[0039] P = V rms *I rms

[0040] V rms : the effective value of the high-frequency voltage loaded to the tissue;

[0041] I rms : the effective value of the high-frequency current loaded to the tissue.

[0042] According to the changes of the impedance and the power, the corresponding software adjustment is performed, the adjustable direct current voltage is finally output through the DA output module, the switching power supply is controlled through the PWM controller, the VCT voltage corresponding to the DA voltage is output, and the relationship is as follows:

[0043] Vvct = k * V DA

[0044] V vct : adjustable DC voltage output by the switching power supply, which can be selected as 0-150V or other approximate values;

[0045] V DA : DC voltage output by the DA module, which can be selected as 0-3.3V or 0-5.0V or other approximate values;

[0046] k: gain coefficient, determined by the hardware circuit, which can be selected as 20-60.

[0047] Through the above adjustment, the changed VCT voltage is loaded to the high-frequency power amplifier module 5, which generates corresponding high-frequency high-voltage output, thereby effectively controlling the energy loading to the tissue.

[0048] A control method of a plasma surgical system for quickly generating plasma state, comprising the following steps:

[0049] S1: When the foot switch 14 and the surgical electrode 8 are in a connected state, the MCU module 1 performs real-time scanning on the state of the foot switch 14, and when the electrocuting pedal of the foot switch 14 is stepped on, the state change is detected by the MCU module 1, and the operation of the electrocuting mode is started, first entering the pretreatment mode;

[0050] S2: judging whether the pretreatment is abnormal, if not, entering the arc striking control;

[0051] S3: judging whether the arc striking is successful, if so, entering the tissue cutting stage;

[0052] S4: the system detects the state of the foot switch 14, when the foot switch 14 is released, all outputs are turned off, and the electrocuting mode is exited; otherwise, the operation of the tissue cutting stage is continued, and the current plasma arc state is judged according to the real-time detected load impedance R m , and when R m decreases by a certain value, which can be selected as R m ≤ 2 * R0, it is considered that the arc is extinguished, and the system reenters step S2 for arc striking control again.

[0053] Further, the pretreatment mode in step S1 comprises the following steps:

[0054] S11: the MCU module 1 controls the switching power supply 3 to output a preset VCT DC voltage (the VCT voltage can be selected as 20-40V) through the DA module, and samples the VCT voltage through the voltage dividing circuit 6 to judge whether the actual output VCT voltage is within the preset range; generally, the preset deviation can be selected as ±20%-±40%.

[0055] S12: control the high frequency power amplifier output by complementary PWM signal, and detect the working state of the high frequency power amplifier module 5 through the feedback circuit, and after normal, detect the high frequency voltage and high frequency current output by the high frequency power amplifier module 5, and calculate the current initial impedance R0.

[0056] Further, when the initial impedance R0 of step S2 is less than a certain value, which can be selected as 200-300 ohms, arc starting control is entered; if any step is abnormal, all outputs are directly closed, and the operation of the cutting mode is ended.

[0057] In addition, step S3 includes the following steps:

[0058] S31: the system controls the switch power supply 3 to output VCT voltage through the DA module, denoted as V vct1 , which can be selected as a certain value between 80-100V;

[0059] S32: after about 1ms delay, the system detects the high frequency voltage and high frequency current output by the high frequency power amplifier module 5, and calculates the current load impedance R1;

[0060] S33: the system increases the VCT voltage output, denoted as V vct2 , V vct2 -V vct1 , which can be selected as a certain value between 0.5V-2V;

[0061] S34: after about 1ms delay according to the above steps, a new load impedance R2 is obtained, and in this way, load impedances R n are obtained in succession. n When the continuously obtained load impedances are all greater than R0, R n ≥(3-5)*R0 can be generally selected, that is, it is considered that the system ionizes and arcs successfully, and enters the tissue cutting stage.

[0062] At the same time, when the arc starting success is judged in step S3, the longest arc starting time is timed, which can be generally selected as 50-100ms, when the time overflows, the energy output is closed, and after a delay, step S3 is re-entered for arc starting control.

[0063] It can be seen that in the tissue cutting stage of step S3, according to the detected load impedance R m and load power P m , the system output power is adjusted in real time in a closed loop, and the adjustment period can be generally selected as 1-10ms, preferably 2ms, and the adjustment algorithm adopts a double competition method, that is, the constant power and constant voltage modes are competed, the module corresponding to the smaller expected VCT voltage obtains the competitive advantage, and the switch power supply 3 is controlled through the DA module to output, so as to maintain the cutting of the tissue with the lowest energy and reduce the thermal damage.

[0064] According to the above steps S1-S4, the plasma arc can be quickly generated, and the power output is performed according to the power level preset by software (the power value or power gear is set through a user interface), so that the cutting smoothness is improved, and thermal damage is minimized, and the clinical effect is improved.

[0065] The system can also realize tissue electrocoagulation, and the working steps are different from the above steps. After steps S1 and S2, the tissue cutting stage is changed to a tissue coagulation stage in step S3. The adjustment algorithm adopts a three-competition method, that is, the output constant current, constant power and constant voltage modes are competed. The module corresponding to the expected smaller VCT voltage has a competitive advantage. The switch power supply 3 is controlled through the DA module to output, so as to coagulate the tissue at the bleeding site with as low energy as possible, and reduce thermal damage.

[0066] Compared with the prior art, the output power is also controlled by the MCU to realize the electrocuting and electrocoagulation operation, but the mainstream technology in the market, such as “controlling the maximum power through a peak value control circuit”, only controls the maximum output power at the initial stage of arc starting to protect the patient from greater harm. The plasma arc state is not detected, and the free energy switching between arc starting and non-arc starting cannot be realized, that is, after the plasma arc is started, the electrocuting is still performed at the maximum power, or when the electrode tip is temporarily separated from the tissue during normal electrocuting and the arc is extinguished, the arc starting program cannot be quickly entered to realize the second plasma arc starting, which affects the clinical experience and actual cutting effect.

[0067] The present application gradually increases the energy applied to the plasma electrode in a physiological saline environment to cause the ordered ionization of Na ions in the physiological saline solution. This method can cause the plasma arc to start more quickly, the arc is not easy to extinguish during electrocuting, the cutting performance is smoother, and the clinical performance is better. At the same time, this dynamic energy loading method can also avoid the disadvantages of fixed energy loading methods: one is that too small loading energy setting leads to insufficient energy, which makes it difficult to start the plasma arc, and the other is that too high loading energy setting leads to an instantaneous burst of too much energy, which causes greater thermal damage to the tissue and brings safety hazards.

[0068] The specific embodiments described herein are merely illustrative of the spirit of the present application. Those skilled in the art of the present application can make various modifications or supplements to the described specific embodiments or replace them with similar ways, without departing from the spirit of the present application or exceeding the scope defined by the appended claims.

[0069] Although the terms MCU module 1, sound control module 11, loudspeaker 12, touch screen 13, foot switch 14, PWM controller 2, switching power supply 3, MOS drive module 4, high-frequency power amplifier module 5, voltage dividing circuit 6, fault detection module 7, surgical electrode 8, voltage detection module 81, current detection module 82, etc. are used more frequently in the present text, the possibility of using other terms is not excluded. The use of these terms is merely for the sake of convenience in describing and explaining the essence of the present application; any kind of additional limitation resulting from their interpretation is contrary to the spirit of the present application.

Claims

1. A plasma surgical system for rapidly generating plasma states, comprising an MCU module (1), characterized in that, The MCU module (1) is connected to the switching power supply (3) via the PWM controller (2). The MCU module (1) is connected to the high-frequency power amplifier module (5) via the MOS driver module (4). A voltage divider circuit (6) connected to the MCU module (1) is connected between the switching power supply (3) and the high-frequency power amplifier module (5). A fault detection module (7) is connected between the high-frequency power amplifier module (5) and the MCU module (1). The high-frequency power amplifier module (5) is connected to the surgical electrode (8), and a voltage detection module (81) and a current detection module (82) connected to the MCU module (1) are arranged between them. The surgical electrode (8) is connected to the MCU module (1). The MCU module (1) is connected to a foot switch (14). When the foot switch (14) is connected to the surgical electrode (8), the MCU module (1) scans the state of the foot switch (14) in real time. When the electrosurgical pedal of the foot switch (14) is pressed, the state change is detected by the MCU module (1). When starting the electric cutting mode, the system first enters the preprocessing mode; it is judged whether there is an abnormality in the preprocessing. If there is no abnormality, it enters the arc control mode; the MCU module (1) controls the switching power supply (3) to output the preset VCT DC voltage through the DA module, and samples the VCT DC voltage through the voltage divider circuit (6) to determine whether the actual output VCT DC voltage is within the preset range; the high-frequency power amplifier output is controlled by the complementary PWM signal, and the working status of the high-frequency power amplifier module (5) is detected by the feedback circuit. After it is normal, the high-frequency voltage and high-frequency current output by the high-frequency power amplifier module (5) are detected, and the current initial impedance R0 is calculated; when the initial impedance R0 is less than a certain value, the arc control mode is entered; during the tissue cutting stage, the system output power is adjusted in real time in a closed loop according to the detected load impedance and load power. The adjustment algorithm adopts the dual competition method, that is, the constant power and constant voltage modes are competitive. The module corresponding to the expected smaller VCT voltage gains the competitive advantage and controls the output of the switching power supply (3) through the DA module.

2. The plasma surgical system for rapidly generating plasma state according to claim 1, characterized in that, The MCU module (1) is connected to a speaker (12) via a sound control module (11).

3. The plasma surgical system for rapidly generating plasma state according to claim 1, characterized in that, The MCU module (1) is connected to a touch screen (13).

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