A low-temperature plasma system capable of accurately testing impedance

Abstract

The present invention relates to the field of medical devices, and in particular to a low-temperature plasma system capable of accurately testing impedance, comprising: a single-chip microcomputer control module, a power supply module, an output module, a DC overcurrent protection circuit, a VPK acquisition circuit, an output voltage acquisition circuit, and an output current acquisition circuit; the power supply module comprises: a DC-DC circuit, an input overvoltage and undervoltage protection circuit, and an overcurrent protection circuit; the output module comprises: an output transformer, a DC bus voltage detection circuit, an input voltage detection circuit, an output voltage detection circuit, and an output current detection circuit; the DC bus voltage detection circuit and the input voltage detection circuit are arranged on the primary side of the output transformer, and the output voltage detection circuit and the output current detection circuit are arranged on the secondary side of the output transformer.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to a low-temperature plasma system capable of accurately testing impedance. Background Art

[0002] The development of modern science and technology has promoted progress in various fields. Low-temperature plasma technology has become an inevitable product of the development of the times and has been widely used in the electronics industry, material surface modification, disinfection and sterilization, waste treatment, and medical fields.

[0003] Low-temperature plasma utilizes its highly active and high-energy properties to excise biological tissue or ablate diseased tissue. Low-temperature plasma ablation is a minimally invasive procedure, offering advantages such as minimal surgical trauma and rapid recovery, significantly alleviating patient pain and shortening recovery time. Furthermore, compared to radiofrequency ablation, the operating temperature is lower (40-70°C), avoiding the carbonization of biological tissue caused by high temperatures (carbonized tissue cannot be metabolized and excreted from the body).

[0004] Low-temperature plasma ablation uses ionized saline to generate plasma, which, when applied to biological tissue, produces both a cryogenic decomposition effect and a thermal effect. The highly reactive ions can break the molecular bonds of organic matter, reacting with cellular proteins and nucleic acids, damaging cell membranes and ultimately killing them. Furthermore, the ions, driven by the rapid changes in the electromagnetic field, move back and forth along the magnetic field lines. Friction between the high-energy ions generates heat, and the high temperature can denature proteins in cellular tissue and dry out blood.

[0005] The application of low-temperature plasma technology in clinical medicine raises biosafety concerns. While it's hoped that plasma can rapidly ablate lesions, it must also be able to avoid fatal damage to normal cells. However, the effectiveness of plasma ablation is affected by numerous factors, including operating temperature, operating pressure, plasma concentration, and plasma distribution uniformity.

[0006] Low-temperature plasma ablation originated in the late 20th century. Compared with other surgical equipment, it has the advantages of high safety, low operating temperature, small surgical damage, fast postoperative recovery, wide indications, few complications, and good efficacy. It has a simple structure and low cost, so it is widely used in clinical treatment.

[0007] In 1993, Pelletier published an article examining the working mechanism of low-temperature plasma sterilization. This research demonstrated that low-temperature plasma is highly reactive and readily reacts with bacterial proteins, nucleic acids, and other substances, effectively inactivating a wide range of pathogens. Because diseased tissue is more sensitive to temperature than normal tissue, an appropriate amount of plasma applied to the human body can accelerate apoptosis of diseased tissue without causing additional damage to surrounding healthy tissue. Consequently, low-temperature plasma is widely used in cancer treatment and clinical surgery, minimizing unnecessary harm to the body and preventing the side effects of medication.

[0008] In recent years, with the continuous development of plasma ablation technology, its application in clinical medicine has become increasingly extensive. This has necessitated independent research and development of plasma surgical systems from the very beginning. This requires developing a new generation of low-temperature plasma surgical systems.

[0009] Low-temperature plasma systems are commonly used in laparoscopic surgery. During laparoscopy, boiling saline can easily obscure the field of view. To address this limitation, a new intelligent low-temperature plasma system has been developed. This system uses impedance analysis to monitor the system's power output in real time, thereby controlling the system's plasma generation effect. This intelligently controls the system's energy output, achieving the desired surgical outcome while effectively preventing boiling saline and obstructing the field of view. Summary of the Invention

[0010] The purpose of the present invention is to solve the problems in the background technology and provide a low-temperature plasma system that can accurately test impedance.

[0011] The above technical objectives of the present invention are achieved through the following technical solutions:

[0012] A low-temperature plasma system capable of accurately testing impedance comprises: a single-chip microcomputer control module, a power module, an output module, a DC overcurrent protection circuit, a VPK acquisition circuit, an output voltage acquisition circuit, and an output current acquisition circuit; the power module comprises: a DC-DC circuit, an input overvoltage and undervoltage protection circuit, and an overcurrent protection circuit; the output module comprises: an output transformer, a DC bus voltage detection circuit, an input voltage detection circuit, an output voltage detection circuit, and an output current detection circuit; the DC bus voltage detection circuit and the input voltage detection circuit are arranged on the primary side of the output transformer, and the output voltage detection circuit and the output current detection circuit are arranged on the secondary side of the output transformer; the input voltage detection circuit processes a signal via the VPK acquisition circuit and transmits the processed signal to the single-chip microcomputer control module; the output voltage detection circuit processes a signal via the output voltage acquisition circuit and transmits the processed signal to the single-chip microcomputer control module; and the output current detection circuit processes a signal via the output current acquisition circuit and transmits the processed signal to the single-chip microcomputer control module.

[0013] Preferably, the DC-DC circuit includes: a rectifier and filter circuit, an inductive DC-DC full-bridge circuit, and the input overvoltage and undervoltage protection circuit is connected between the rectifier and filter circuit and the inductive DC-DC full-bridge circuit; the inductive DC-DC full-bridge circuit is divided into two leading bridge arms and two lagging bridge arms, and is controlled by an induction coil, which is controlled by T1A_DRIV and T1B_DRIV signals issued by the DC overcurrent protection circuit.

[0014] Preferably, the input overvoltage and undervoltage protection circuit includes a diode D2, a resistor R2, an optocoupler OP1, and a voltage collection output terminal. After rectification and filtering, the mains power input passes through diode D2, resistor R2, and optocoupler OP1 to form a loop. The input voltage can be calculated based on the different conduction levels of the optocoupler. When overvoltage or undervoltage occurs, the output can be promptly shut down to achieve overvoltage or undervoltage protection.

[0015] Preferably, the overcurrent protection circuit is provided in the inductive DC-DC full-bridge circuit and includes a current transformer T3, a rectifier bridge, and an I_LIMIT signal output terminal. Current is collected by the current transformer and rectified by CR5, CR6, CR7, and CR8 before outputting an I_LIMIT signal. This signal is connected to R34 of the output module and, after filtering and voltage division, is transmitted to pin 9 of chip U2. When the circuit current is excessive and the voltage sensed by the transformer exceeds the protection threshold of that pin, the pulse modulation outputs of pins 11 and 14 of chip U2 are turned off, the T1A_DRIV and T1B_DRIV signals are turned off, and the full-bridge conversion circuit stops operating, thereby achieving circuit protection when the circuit current is excessive.

[0016] Preferably, the DC overcurrent protection circuit includes: a PWM control chip, specifically a UC3825, an I_LIMIT current signal input, a pulse modulation signal output, and a system mode signal input. The UC3825 chip has two opposing output signals, forming a push-pull control signal. This allows the push-pull circuit in an inductive DC-DC full-bridge circuit to operate so that only one of the two symmetrical power switches is turned on at a time, thereby reducing conduction losses.

[0017] Preferably, the DC bus voltage detection circuit is arranged at the primary side 1 pin of the output transformer, including an HV_SEN signal output end and a voltage divider resistor R39 and a voltage divider resistor R44 connected in series, and the HV_SEN signal output end is arranged between the voltage divider resistor R39 and the voltage divider resistor R44.

[0018] Preferably, the input voltage detection circuit is arranged at the primary side 2 pin of the output transformer, including a VSE signal output end and a voltage divider resistor R45, a voltage divider resistor R49 and a voltage divider resistor R57 connected in series, and the VSE signal output end is arranged between the voltage divider resistor R45 and the voltage divider resistor R49.

[0019] Preferably, the output voltage detection circuit is arranged between the secondary pins 3 and 4 of the output transformer, and includes: a mutual inductor T6, a voltage dividing resistor and a V_SEN_IN1 signal output terminal.

[0020] Preferably, the output current detection circuit is arranged at the secondary output end of the output transformer, and includes: a mutual inductor T7, a voltage dividing resistor and an I_SEN_IN1 signal output end.

[0021] Preferably, the VPK acquisition circuit includes: a VSE signal input terminal, a filter amplifier circuit and a VPK signal output terminal; the output voltage acquisition circuit includes: a V_SEN_IN1 signal input terminal, a rectifier filter amplifier circuit and a V_SEN_1 signal output terminal; the output current acquisition circuit includes: an I_SEN_IN1 signal input terminal, a rectifier filter amplifier circuit and an I_SEN signal output terminal.

[0022] In summary, the beneficial effects of the present invention are:

[0023] 1. The low-temperature plasma system capable of accurately testing impedance described in the present invention has an input overvoltage and undervoltage protection circuit. When the system experiences overvoltage or undervoltage, it can promptly shut down the output to achieve overvoltage or undervoltage protection. The DC overcurrent protection circuit stops the full-bridge converter circuit when the circuit current is too large and the voltage sensed by the transformer exceeds the protection threshold of the pin, thus achieving circuit protection when the circuit current is too large.

[0024] 2. The low-temperature plasma system capable of accurately testing impedance described in the present invention effectively detects the output voltage and current in real time under load, feeds back the input to the single-chip microcomputer chip, and combines the algorithm of the control chip to calculate the impedance, thereby comprehensively controlling the power output of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic diagram of the present invention;

[0026] Figure 2 is a schematic diagram of the power module of the present invention;

[0027] Figure 3 is a schematic diagram of a DC overcurrent protection circuit in the present invention;

[0028] Figure 4 is a schematic diagram of the output module in the present invention;

[0029] Figure 5 It is a schematic diagram of the VPK acquisition circuit in the present invention;

[0030] Figure 6 is a schematic diagram of the output voltage acquisition circuit in the present invention;

[0031] Figure 7 It is a schematic diagram of the output current acquisition circuit in the present invention. DETAILED DESCRIPTION

[0032] The following specific embodiments are merely explanations of the present invention and are not limitations of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the embodiments as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by patent law.

[0033] The present invention will be described in detail below with reference to the accompanying drawings using embodiments. Example

[0034] according to Figure 1 As shown, a low-temperature plasma system capable of accurately testing impedance includes: a single-chip control module 1, a power module 2, an output module 3, a DC overcurrent protection circuit 4, a VPK acquisition circuit 5, an output voltage acquisition circuit 6, and an output current acquisition circuit 7.

[0035] according to Figure 2 As shown, the power module 2 includes: a DC-DC circuit 21 , an input overvoltage and undervoltage protection circuit 22 , and an overcurrent protection circuit 23 .

[0036] The DC-DC circuit 21 includes: a rectifier and filter circuit 211, an inductive DC-DC full-bridge circuit 212, wherein the inductive DC-DC full-bridge circuit 212 is divided into two leading bridge arms and two lagging bridge arms, and is controlled by an induction coil, which is controlled by the T1A_DRIV and T1B_DRIV signals issued by the DC overcurrent protection circuit 4.

[0037] The input overvoltage and undervoltage protection circuit 22 is connected between the rectifier and filter circuit 211 and the inductive DC-DC full-bridge circuit 212; the input overvoltage and undervoltage protection circuit 22 includes: a diode D2, a resistor R2, an optocoupler OP1 and a PV_SEN voltage collection output terminal. After the mains power input is rectified and filtered, a loop is formed through the diode D2, the resistor R2 and the optocoupler OP1. The input voltage can be calculated based on the different conduction of the optocoupler. When overvoltage and undervoltage occur, the output can be turned off in time to achieve overvoltage or undervoltage protection.

[0038] according to Figure 3 As shown, the DC overcurrent protection circuit 4 includes: a PWM control chip 41, which is UC3825 in this embodiment, an I_LIMIT current signal input terminal 42, a pulse modulation signal output terminal 43, the pulse modulation signal output terminal 43 is connected to pins 11 and 14 of the UC3825 chip, thereby outputting T1A_DRIV and T1B_DRIV signals, and a SYS_ECOM system mode signal input terminal 44.

[0039] The overcurrent protection circuit 23 is set in the inductive DC-DC full-bridge circuit. The overcurrent protection circuit 23 includes: a current transformer T3, a rectifier bridge, and an I_LIMIT signal output terminal. The current is collected by the current transformer, and then rectified by CR5, CR6, CR7, and CR8 to output the I_LIMIT signal. This signal is connected to R34, filtered and divided, and then transmitted to pin 9 of the chip UC3825. When the current in the circuit is too large and the voltage sensed by the transformer exceeds the protection threshold of this pin, the pulse modulation output of pins 11 and 14 of the chip UC3825 is turned off. Figure 1 The T1A_DRIV and T1B_DRIV signals in the circuit are turned off, and the full-bridge conversion circuit stops working, thereby realizing circuit protection when the circuit current is too large.

[0040] according to Figure 4 As shown, the output module 3 includes: an output transformer T5 31, a DC bus voltage detection circuit 32, an input voltage detection circuit 33, an output voltage detection circuit 34, and an output current detection circuit 35; the DC bus voltage detection circuit 32 and the input voltage detection circuit 33 are arranged on the primary side of the output transformer T5 31, and the output voltage detection circuit 34 and the output current detection circuit 35 are arranged on the secondary side of the output transformer T5 31.

[0041] The DC bus voltage detection circuit 32 is provided at the primary side 1 pin of the output transformer T5 31 and includes an HV_SEN signal output terminal and a voltage divider resistor R39 and a voltage divider resistor R44 connected in series. The HV_SEN signal output terminal is provided between the voltage divider resistor R39 and the voltage divider resistor R44.

[0042] The input voltage detection circuit 33 is provided at the primary side 2 pin of the output transformer T5 31 and includes a VSE signal output terminal and a voltage divider resistor R45, a voltage divider resistor R49 and a voltage divider resistor R57 connected in series. The VSE signal output terminal is provided between the voltage divider resistor R45 and the voltage divider resistor R49.

[0043] The output voltage detection circuit 34 is provided between the secondary pins 3 and 4 of the output transformer T5 31 and includes a transformer T6 , a voltage dividing resistor and a V_SEN_IN1 signal output terminal.

[0044] The output current detection circuit 35 is provided at the secondary output terminal of the output transformer T5 31 and includes: a mutual inductor T7 , a voltage dividing resistor and an I_SEN_IN1 signal output terminal.

[0045] according to Figures 5 to 7 As shown, the VPK acquisition circuit 5 includes: a VSE signal input terminal, a filter amplifier circuit and a VPK signal output terminal; the output voltage acquisition circuit 6 includes: a V_SEN_IN1 signal input terminal, a rectifier filter amplifier circuit and a V_SEN_1 signal output terminal; the output current acquisition circuit 7 includes: an I_SEN_IN1 signal input terminal, a rectifier filter amplifier circuit and an I_SEN signal output terminal.

[0046] Input voltage detection circuit 33 processes the VSE signal through VPK acquisition circuit 5, converting it into a VPK signal and transmitting it to single-chip control module 1. Output voltage detection circuit 34 processes the V_SEN_IN1 signal through output voltage acquisition circuit 6, converting it into a V_SEN_1 signal and transmitting it to single-chip control module 1. Output current detection circuit 35 processes the I_SEN_IN1 signal through output current acquisition circuit 7, converting it into an I_SEN signal and transmitting it to single-chip control module 1. Single-chip control module 1 calculates impedance in real time based on the VPK, V_SEN_1, and I_SEN_IN1 signals and controls system operation.

Claims

1. A low-temperature plasma system capable of accurately testing impedance, characterized in that: include: A single chip microcomputer control module (1), a power module (2), an output module (3), a DC overcurrent protection circuit (4), a VPK acquisition circuit (5), an output voltage acquisition circuit (6), and an output current acquisition circuit (7); The power supply module (2) comprises: a DC-DC circuit (21), an input overvoltage and undervoltage protection circuit (22), and an overcurrent protection circuit (23); The output module (3) includes: an output transformer (31), a DC bus voltage detection circuit (32), an input voltage detection circuit (33), an output voltage detection circuit (34), and an output current detection circuit (35); the DC bus voltage detection circuit (32) and the input voltage detection circuit (33) are arranged on the primary side of the output transformer (31), and the output voltage detection circuit (34) and the output current detection circuit (35) are arranged on the secondary side of the output transformer (31); the DC bus voltage detection circuit (32) is arranged on pin 1 of the primary side of the output transformer (31), and includes an HV_SEN signal output terminal and a voltage divider resistor R39 and a voltage divider resistor R44 connected in series, and the HV_SEN signal output terminal The input voltage detection circuit (33) is arranged between the voltage-dividing resistor R39 and the voltage-dividing resistor R44; the input voltage detection circuit (33) is arranged at the primary side 2 pin of the output transformer (31), including a VSE signal output terminal and a voltage-dividing resistor R45, a voltage-dividing resistor R49 and a voltage-dividing resistor R57 connected in series, and the VSE signal output terminal is arranged between the voltage-dividing resistor R45 and the voltage-dividing resistor R49; the output voltage detection circuit (34) is arranged between the secondary side 3 and 4 pins of the output transformer (31), including: a mutual inductor T6, a voltage-dividing resistor and a V_SEN_IN1 signal output terminal; the output current detection circuit (35) is arranged at the secondary side output terminal of the output transformer (31), including: a mutual inductor T7, a voltage-dividing resistor and an I_SEN_IN1 signal output terminal; The input voltage detection circuit (33) processes the signal through the VPK acquisition circuit (5) and transmits the processed signal to the single-chip control module (1); the output voltage detection circuit (34) processes the signal through the output voltage acquisition circuit (6) and transmits the processed signal to the single-chip control module (1); and the output current detection circuit (35) processes the signal through the output current acquisition circuit (7) and transmits the processed signal to the single-chip control module (1).

2. A low-temperature plasma system capable of accurately testing impedance according to claim 1, characterized in that: The DC-DC circuit (21) comprises: a rectifier filter circuit (211) and an inductive DC-DC full-bridge circuit (212); the input overvoltage and undervoltage protection circuit (22) is connected between the rectifier filter circuit (211) and the inductive DC-DC full-bridge circuit (212).

3. A low-temperature plasma system capable of accurately testing impedance according to claim 1, characterized in that: The input overvoltage and undervoltage protection circuit (22) comprises: a diode D2, a resistor R2, an optical coupler OP1 and a voltage collection output terminal.

4. A low-temperature plasma system capable of accurately testing impedance according to claim 2, characterized in that: The overcurrent protection circuit (23) is arranged at the inductive DC-DC full-bridge circuit (212), and the overcurrent protection circuit (23) comprises: a current transformer T3, a rectifier bridge, and an I_LIMIT signal output terminal.

5. The low-temperature plasma system capable of accurately testing impedance according to claim 1, characterized in that: The DC overcurrent protection circuit (4) comprises: a PWM control chip (41), an I_LIMIT current signal input terminal (42), a pulse modulation signal output terminal (43), and a system mode signal input terminal (44).

6. The low-temperature plasma system capable of accurately testing impedance according to claim 1, characterized in that: The VPK acquisition circuit (5) includes: a VSE signal input terminal, a filter amplifier circuit, and a VPK signal output terminal; the output voltage acquisition circuit (6) includes: a V_SEN_IN1 signal input terminal, a rectifier filter amplifier circuit, and a V_SEN_1 signal output terminal; the output current acquisition circuit (7) includes: an I_SEN_IN1 signal input terminal, a rectifier filter amplifier circuit, and an I_SEN signal output terminal.

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