Multi-electrode synergistic air plasma disinfection and sterilization device and control method thereof

Abstract

The invention discloses a multi-electrode synergistic air plasma disinfection and sterilization device and a control method thereof. The device comprises an insulating substrate, a discharge electrode group consisting of at least three electrodes, a high-voltage pulse power supply and a high-frequency alternating-current power supply. The three electrodes are endowed with different function roles and work cooperatively, the first electrode serves as a main discharge electrode to be connected to a pulse power supply, the second electrode serves as a grounding electrode to form a discharge loop, and the third electrode serves as an auxiliary electrode to be connected to an alternating-current auxiliary power supply. The main plasma area generated by the main discharge electrode and the grounding electrode is actively modulated and coordinated through the electric field and the seed electrons generated by the auxiliary electrode, so that the discharge area is obviously enlarged, and the uniformity and the stability of plasma distribution are greatly improved. The method effectively solves the problem of poor discharge uniformity of the air plasma, and the device has the characteristic of long service life.

Description

Technical Field

[0001] This invention relates to the field of air disinfection and sterilization technology, and in particular to a multi-electrode synergistic air plasma disinfection and sterilization device and its control method. Background Technology

[0002] In daily life, people inevitably come into contact with viruses and bacteria, most of which can spread through the air as aerosols, seriously endangering human health. Therefore, air sterilization and disinfection are essential technologies in modern life. Disinfection refers to the use of chemical or physical methods to kill or eliminate pathogenic microorganisms on transmission media, preventing their spread and infection. Sterilization refers to the process of eliminating or killing all microorganisms in the external environment. In recent years, large-scale epidemics and diseases caused by various pathogenic microorganisms have broken out and spread continuously around the world.

[0003] Current disinfection and sterilization technologies mainly rely on two methods: chemical oxidation (such as chlorination and ozone) and physical inactivation (ultraviolet light and high temperature). The former is prone to forming carcinogenic byproducts and corroding instrument surfaces due to the residue of strong oxidants, while the latter is limited by problems such as weak penetration, high energy consumption, and poor material compatibility. Compared with traditional processes, low-temperature plasma technology uses highly active particles to directionally decompose the structure of microorganisms, combining highly efficient sterilization (Bacillus subtilis spore kill rate >99.9%) with green and pollution-free characteristics. However, its industrial application is still limited by high equipment costs, insufficient processing uniformity, and lack of continuous operation capability.

[0004] While plasma generated in air mostly exhibits arc discharge, it is difficult to achieve the characteristics of glow discharge, such as low temperature, high density, good discharge uniformity, low energy consumption, and high processing efficiency. Therefore, achieving glow discharge in air is a more ideal method for plasma generation for disinfection and sterilization. Summary of the Invention

[0005] The purpose of this invention is to solve the problems of low density, poor discharge uniformity, and high energy consumption in current air plasma disinfection sources. To this end, a multi-electrode synergistic air plasma disinfection and sterilization device and its control method are provided.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A multi-electrode synergistic air plasma disinfection and sterilization device, comprising: Insulating substrate; The discharge electrode assembly consists of three discharge electrodes spaced apart from each other and fixed on the insulating substrate. The power supply system includes a high-voltage pulse power supply and a high-frequency AC power supply; The first electrode of the three discharge electrodes is electrically connected to the high-voltage output terminal of the high-voltage pulse power supply and serves as the main discharge electrode; the second electrode of the three discharge electrodes is electrically connected to the common ground terminal and serves as the ground electrode; and the third electrode of the three discharge electrodes is electrically connected to the output terminal of the high-frequency AC power supply and serves as the auxiliary electrode. The auxiliary electrode is configured to modulate the main plasma region generated between the main discharge electrode and the ground electrode through the high-frequency alternating electric field and seed electrons it generates, so as to improve the spatial distribution uniformity of the plasma.

[0007] The following is a further technical solution for the device in this invention: the projection points of the first electrode, the second electrode, and the third electrode on the insulating substrate form a right-angled triangle vertex, and the distance between the first electrode and the second electrode is greater than the distance between the second electrode and the third electrode.

[0008] The following is a further technical solution for the device in this invention: the distance between the two right-angled sides of the right triangle formed by the three discharge electrodes is 1.8-2.5mm and 0.3-0.5mm, respectively.

[0009] The following is a further technical solution for the device in this invention: the discharge electrode includes a metal core and an insulating shield tube sleeved outside the metal core, and the inner wall of the insulating shield tube is covered with a conductive layer.

[0010] The following is a further technical solution for the device in this invention: the metal core is made of tungsten-copper alloy, and the head of the metal core is machined with a semi-annular groove and a rectangular slot.

[0011] The following is a further technical solution for the device in this invention: the diameter of the metal core is 2.5-4.6 mm and the length is 10 cm-15 cm.

[0012] The following is a further technical solution for the device in this invention, wherein the insulating shielding tube is a quartz tube.

[0013] The following is a further technical solution for the device in this invention: the outer diameter of the insulating shield tube is 4.0-7.5 mm and the length is 14-18 cm.

[0014] A control method for multi-electrode synergistic air plasma disinfection and sterilization, applied to the aforementioned device, includes: applying different electrical signals to three discharge electrodes of the device: applying a high-voltage pulse signal to the first electrode, making it the main discharge electrode; applying a grounding signal to the second electrode, making it and the first electrode form a main discharge circuit; applying a high-frequency AC signal to the third electrode, making it an auxiliary electrode; and through the high-frequency alternating electric field generated by the auxiliary electrode, synergistically interacting with the main plasma region generated by the main discharge circuit, thereby exciting a large-area, uniform, and stable air plasma to achieve disinfection and sterilization.

[0015] The following is a further technical solution for the method of the present invention: the frequency of the high-voltage pulse signal is 5~6kHz, the voltage amplitude is 11~15kV, and the pulse width is 2μs; the frequency of the high-frequency AC signal is 20~24kHz, the voltage amplitude is 10~13kV, and the frequency and amplitude range of the electrical signal are changed according to different discharge gaps.

[0016] Compared with the prior art, the present invention has the following technical effects: (1) This invention proposes a multi-electrode collaborative working mechanism of "power-grounding-auxiliary". By actively modulating the main discharge plasma region through the high-frequency AC electric field of the auxiliary electrode, the single-path discharge mode is fundamentally changed, realizing the large-area expansion of the discharge region and the uniform distribution of plasma density, thereby significantly improving the uniformity and reliability of disinfection and sterilization.

[0017] (2) Based on the above-mentioned synergistic mechanism, the discharge of this device is more stable and gentle, effectively avoiding local arcing or excessive discharge. This not only improves the safety of the disinfection process, but also reduces the requirements for the power supply system, which helps to control the overall energy consumption and equipment cost.

[0018] (3) The present invention adopts an insulating tube (such as a quartz tube) shielding electrode design in terms of structure, which physically isolates the metal electrode from the region of generated active particles, greatly reducing the erosion of the electrode by highly active oxidizing substances, thereby solving the technical problem of easy wear and tear of plasma equipment electrodes and significantly extending the service life of the device. (4) The collaborative control method protected by this invention is ingeniously conceived and highly versatile. It has low dependence on the specific shape and preparation process of the electrodes, and is easy to implement and apply in disinfection devices of different sizes and powers, providing a solid foundation for the promotion of air plasma disinfection technology.

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of a single discharge electrode of the present invention; Figure 2 This is a schematic diagram of the disinfection unit of the present invention; Figure 3 This is a graph showing the changes in discharge effect. Detailed Implementation

[0022] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0023] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0024] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0025] In the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.

[0026] The following embodiments are intended to further illustrate the "multi-electrode collaboration" working mechanism of the present invention through specific structural configurations and electrical connections, rather than to limit the scope of protection of the present invention.

[0027] Example 1: This embodiment provides a multi-electrode synergistic air plasma disinfection and sterilization device and its control method.

[0028] 1. Device structure configuration: See Figure 1 The single discharge electrode of the device adopts a layered structure: the inside is a tungsten copper alloy metal core 1 with a diameter of 3.8 mm and a length of 15 cm, and its head is machined with a semi-circular groove and a rectangular slot; the outside is a quartz tube 2 that is sleeved on the metal core 1 as an insulating shield tube, and the inner wall of the quartz tube is coated with a conductive silver paste layer to ensure electrical connection with the metal core 1.

[0029] See Figure 2 The disinfection unit of the device consists of three single discharge electrodes fixed on a polytetrafluoroethylene insulating substrate 3. The insertion points of the three discharge electrodes are arranged in a right-angled triangle, with the distance between the two right-angled sides being 2.5 mm (large gap) and 0.5 mm (small gap), respectively.

[0030] 2. Electrical connection and collaborative operation control methods: The core of this invention lies in the electrical connection method of the three electrodes and their synergistic effect: The discharge electrode located at the vertex of the longer side of the right triangle is defined as the first electrode, and it is connected to the high-voltage output terminal of a high-voltage pulse power supply. The parameters of the high-voltage pulse power supply are set as follows: frequency 5kHz, voltage amplitude 13kV, and pulse width 3μs. This electrode serves as the main discharge electrode. The discharge electrode located at the right-angle vertex of the right triangle is defined as the second electrode and connected to the common ground terminal. This electrode serves as the ground electrode and, together with the first electrode, forms the main discharge circuit.

[0031] The discharge electrode located at the vertex of the shorter side of the right triangle is defined as the third electrode and connected to the output of a high-frequency AC power supply. The parameters of the high-frequency AC power supply are set as follows: frequency 20kHz, voltage amplitude 11kV. This electrode serves as an auxiliary electrode.

[0032] 3. Work process and results: After connecting the power, see Figure 3 A strong electric field is first established between the first and second electrodes, generating pulsed plasma and forming the main plasma region. Simultaneously, a high-frequency alternating electric field generated by the third electrode penetrates deep into this main plasma region, effectively modulating and confining charged particles and active groups. This synergistic effect "expands" and "flattens" the plasma originally concentrated along the AB path, ultimately exciting a large-area, highly uniform, stable air plasma within and around the triangular unit, thus achieving highly efficient space air sterilization and disinfection. Example 2: This embodiment provides another multi-electrode synergistic air plasma disinfection and sterilization device with different parameter configurations.

[0033] 1. Device structure configuration: The single discharge electrode structure of the device is the same as in Example 1. Its disinfection unit consists of three electrodes fixed to a polytetrafluoroethylene (PTFE) insulating substrate 3, which is 8 cm long and wide and 6 mm thick. The insertion points of the three electrodes are arranged in a right-angled triangle, with the distance between the two right-angled sides being 2.2 mm (large gap) and 0.3 mm (small gap), respectively. The metal core 1 of the single discharge electrode has a diameter of 4.6 mm and a length of 12 cm; the outer insulating shielding tube 2 has an outer diameter of 7.5 mm and a length of 18 cm.

[0034] 2. Electrical connection and collaborative operation control methods: The core of this embodiment lies in the specific electrical connection of the three electrodes: The discharge electrode located at the vertex of the longer side of the right triangle (on one side with a spacing of 2.2 mm) is defined as the first electrode (main discharge electrode) and connected to a high-voltage pulse power supply. The parameters of the high-voltage pulse power supply are set as follows: frequency 8 kHz, voltage amplitude 15 kV, and pulse width 2 μs. The discharge electrode located at the right-angle vertex of the right triangle is defined as the second electrode (grounding electrode) and is reliably grounded. The discharge electrode located at the vertex of the shorter side of the right triangle (on the side with a spacing of 0.3 mm) is defined as the third electrode (auxiliary electrode) and connected to a high-frequency AC power supply. The parameters of the high-frequency AC power supply are set as follows: frequency 24 kHz, voltage amplitude 9 kV.

[0035] 3. Work Results: After the power is turned on, a main plasma region is generated through the main discharge electrode and the ground electrode, and is effectively modulated by the high-frequency electric field of the auxiliary electrode. Under these parameters, the device can also excite a large-area, uniform plasma, verifying the universality and effectiveness of the invention under different sizes and electrical parameters.

[0036] Example 3: This embodiment provides a miniaturized configuration of a multi-electrode synergistic air plasma disinfection and sterilization device.

[0037] 1. Device structure configuration: The device uses smaller components. The insulating substrate 3 of the disinfection unit is 4cm long and wide, and 6mm thick. The three electrodes are arranged in a right-angled triangle with spacings of 1.8mm (large gap) and 0.4mm (small gap). The metal core 1 of a single discharge electrode has a diameter of 2.5mm and a length of 10cm; the outer insulating shield tube 2 has an outer diameter of 4.0mm and a length of 14cm.

[0038] 2. Electrical connection and collaborative operation control methods: Its collaborative working logic is as follows: The vertex electrode on one side with a spacing of 1.8 mm is used as the first electrode (main discharge electrode) and connected to a high-voltage pulse power supply with parameters of frequency 5 kHz, voltage amplitude 12 kV, and pulse width 3 μs. The right-angle vertex electrode is used as the second electrode (ground electrode) and grounded. The vertex electrode on one side with a spacing of 0.4 mm is used as the third electrode (auxiliary electrode) and connected to a high-frequency AC power supply with parameters of 15 kHz frequency and 10 kV voltage amplitude.

[0039] 3. Work Results: This configuration demonstrates that the technical solution described in this invention is scalable and adaptable to different spatial disinfection needs. Even in miniaturized devices, the "power-grounding-auxiliary" synergistic mechanism can still operate reliably, generating uniform and stable plasma for disinfection.

[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any person skilled in the art can make many possible variations and modifications to the technical solution of the present invention using the methods and techniques disclosed above, or modify it into equivalent embodiments with equivalent changes, without departing from the scope of the present invention. Therefore, all equivalent changes made based on the shape, structure, and principle of the present invention without departing from the scope of the present invention should be covered within the protection scope of the present invention.

Claims

1. A multi-electrode synergistic air plasma disinfection and sterilization device, characterized in that, include: Insulating substrate; The discharge electrode assembly consists of three discharge electrodes spaced apart from each other and fixed on the insulating substrate. The power supply system includes a high-voltage pulse power supply and a high-frequency AC power supply; The first electrode of the three discharge electrodes is electrically connected to the high-voltage output terminal of the high-voltage pulse power supply and serves as the main discharge electrode; the second electrode of the three discharge electrodes is electrically connected to the common ground terminal and serves as the ground electrode; and the third electrode of the three discharge electrodes is electrically connected to the output terminal of the high-frequency AC power supply and serves as the auxiliary electrode. The auxiliary electrode is configured to modulate the main plasma region generated between the main discharge electrode and the ground electrode through the high-frequency alternating electric field and seed electrons it generates, so as to improve the spatial distribution uniformity of the plasma.

2. The multi-electrode synergistic air plasma disinfection and sterilization device as described in claim 1, characterized in that, The projection points of the first electrode, the second electrode, and the third electrode on the insulating substrate form the vertex of a right triangle, and the distance between the first electrode and the second electrode is greater than the distance between the second electrode and the third electrode.

3. The multi-electrode synergistic air plasma disinfection and sterilization device as described in claim 2, characterized in that, The distance between the two legs of the right triangle formed by the three discharge electrodes is 1.8-2.5 mm and 0.3-0.5 mm, respectively.

4. The multi-electrode synergistic air plasma disinfection and sterilization device as described in claim 1, characterized in that, The discharge electrode includes a metal core and an insulating shielding tube sleeved outside the metal core, the inner wall of which is covered with a conductive layer.

5. The multi-electrode synergistic air plasma disinfection and sterilization device as described in claim 4, characterized in that, The metal core is made of tungsten-copper alloy, and the head of the metal core is machined with a semi-annular groove and a rectangular slot.

6. The multi-electrode synergistic air plasma disinfection and sterilization device as described in claim 5, characterized in that, The metal core has a diameter of 2.5-4.6 mm and a length of 10 cm-15 cm.

7. The multi-electrode synergistic air plasma disinfection and sterilization device as described in claim 4, characterized in that, The insulating shielding tube is a quartz tube.

8. The multi-electrode synergistic air plasma disinfection and sterilization device as described in claim 7, characterized in that, The outer diameter of the insulating shielding tube is 4.0-7.5mm, and the length is 14-18cm.

9. A control method for multi-electrode synergistic air plasma disinfection and sterilization, applied to the device described in any one of claims 1-8, characterized in that, The method includes: applying different electrical signals to the three discharge electrodes of the device: applying a high-voltage pulse signal to the first electrode to make it the main discharge electrode; applying a grounding signal to the second electrode to form a main discharge circuit together with the first electrode; applying a high-frequency AC signal to the third electrode to make it an auxiliary electrode; and using the high-frequency alternating electric field generated by the auxiliary electrode to work synergistically with the main plasma region generated by the main discharge circuit to excite a large-area, uniform and stable air plasma to achieve disinfection and sterilization.

10. The control method for multi-electrode synergistic air plasma disinfection and sterilization as described in claim 9, characterized in that, The high-voltage pulse signal has a frequency of 5~6kHz, a voltage amplitude of 11~15kV, and a pulse width of 2μs; the high-frequency AC signal has a frequency of 20~24kHz and a voltage amplitude of 10~13kV, and the frequency and amplitude range of the electrical signal are changed according to different discharge gaps.

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