A low-voltage sliding arc igniter based on swirl semiconductor

Abstract

A low-voltage sliding arc igniter based on a swirl semiconductor comprises a jet hole (101), a housing (102), an external air duct (103), a mounting thread (104), a cathode (105), an insulator (106), an anode (107), an air flow channel (108), a semiconductor swirl (109), an air inlet hole (110), a positioning step (111), and an air inlet channel (112). The operating process of the igniter is also provided. The present invention utilizes the low-voltage arc starting characteristics of semiconductors to solve the problem that the existing sliding arc igniter requires high-voltage breakdown, thereby solving the problem that the impedance changes greatly during the operation of the existing sliding arc igniter, which increases the difficulty of power supply design. The present invention also utilizes the characteristics of semiconductor devices to effectively reduce the requirements for power supply design, improve engineering practicality, and reduce the volume and weight of the power supply system.

Description

Technical Field

[0001] The present invention is mainly used in the fields of plasma ignition and combustion support, plasma cracking, plasma waste gas treatment, etc., and specifically relates to a low-pressure sliding arc igniter of a swirl semiconductor. Background Art

[0002] Unlike conventional spark discharge, sliding arc discharge is a typical example of non-thermal arc discharge. It not only releases high-temperature plasma but also produces a large number of active particles. There are two operating modes during operation: the accompanying breakdown mode and the stable sliding mode. Gliding arc discharge igniters are widely used in the fields of material surface treatment, toxic waste removal, ignition and combustion support, and cracking. Gliding arc discharge is divided into three stages: the first stage is the breakdown of the air to form a plasma discharge channel; the second stage is the development of a plasma discharge channel driven by the swirling gas; the third stage is arc extinction. At the same time as the arc is extinguished, a new arc is formed, and this cycle repeats until a sliding arc is formed.

[0003] Currently, sliding arc excitation systems typically utilize air-gap discharge, using high voltage to break down the air to create a conductive path, creating the conditions for the sliding arc to form. Because air is an insulator before breakdown, the entire excitation system exhibits high impedance. To achieve reliable breakdown, the sliding arc power supply system must initially provide a high voltage. However, once the air breaks down, the air gap resistance rapidly decreases, and the entire excitation system exhibits low impedance. At this point, the arc voltage drop rapidly decreases. However, to ensure a stable sliding arc, a high current is required. Therefore, the sliding arc power supply must provide a low voltage and high current.

[0004] In summary, due to the large difference in impedance between the breakdown process and the stable discharge process of the current sliding arc igniter, the power supply needs to switch between the two working modes, which increases the complexity of the power supply design and causes the power supply volume and weight to increase. Summary of the Invention

[0005] In view of this, in order to solve the problem that the impedance change during the operation of the existing sliding arc igniter is large, which increases the difficulty of power supply design, the present invention proposes a low-voltage sliding arc igniter based on a swirl semiconductor, including a jet hole 101, a shell 102, an external air duct 103, a mounting thread 104, a cathode 105, an insulator 106, an anode 107, an air flow channel 108, a semiconductor cyclone 109, an air inlet hole 110, a positioning step 111, and an air inlet channel 112; wherein

[0006] The housing 102 is in the shape of a hollow cylinder, having an upper end face with a hole punched in the center of the end face; an internal thread is provided at the lower end of the housing 102, and the internal thread is fixedly engaged with the mounting thread 104;

[0007] The external air bleed pipe 103 is fixedly connected to the outer shell 102 at a position near the upper part of the inner thread of the outer shell 102, and the external air bleed pipe 103 does not contact the inner thread of the outer shell 102. The external air bleed pipe 103 is inserted into the outer shell 102 from bottom to top. The outer shell 102 has a hole at the entrance of the external air bleed pipe 103 to allow external air to be introduced through the external air bleed pipe 103.

[0008] The cathode 105 is a hollow cylinder with open ends. The exterior of the cathode 105 is cylindrical, and a gap is left between the outer wall of the cathode 105 and the inner wall of the housing 102 along the circumferential direction, forming an air inlet channel 112. The inner cavity of the cathode 105 is divided into three sections: the head, the middle, and the tail. The inner cavity of the head of the cathode 105 gradually converges towards the head outlet, and the radius gradually decreases. The diameter of the middle part of the inner cavity of the cathode 105 is smaller than the diameter of the tail, and a step is naturally formed in the middle. A positioning step 111 is machined at the tail of the cathode 105 to clamp the insulator 106. The lower end surface of the positioning step 111 maintains a certain distance from the lower end surface of the cathode 105.

[0009] The through hole in the inner cavity of the cathode 105 near the head and the through hole in the head of the shell 102 together form the jet hole 101;

[0010] A mounting thread 104 is processed on the tail of the cathode 105; the mounting thread 104 is located below the air inlet 110 and maintains a certain distance from the air inlet 110;

[0011] Two groups of air inlet holes 110 are arranged in the middle of the inner cavity of the cathode 105 near the head, one above and one below. Each group of air inlet holes includes multiple air inlet holes evenly distributed along the circumference. These air inlet holes are through holes that penetrate the inner and outer walls of the cathode 105. The air inlet holes 110 are connected to the air inlet channel 112, the air flow channel 108 and the jet hole 101.

[0012] The insulator 106 is a hollow structure located between the cathode 105 and the anode 107, and is rotationally symmetrical around the axis of the igniter. The outer wall of the insulator 106 is divided into three cylindrical structures: upper, middle, and lower. The diameter increases from top to bottom. The outer wall of the upper cylinder maintains a certain distance from the inner wall of the cathode 105. The middle cylinder and the upper cylinder are adjacent to each other and protrude outward to form a boss. The boss is located below the two groups of air inlet holes 110 and is in an interference fit with the inner wall of the middle part of the cathode 105 cavity. The junction of the middle cylinder and the lower cylinder The step formed at the cathode 105 corresponds to the shape of the step formed between the middle and tail of the cathode 105, so that the lower cylinder is in close contact with the inner wall of the cathode 105; the internal cavity of the insulator 106 forms two hollow cylindrical structures with different diameters, the upper hollow cylindrical structure has a smaller diameter than the lower hollow cylindrical structure, and the two together form a through hole; the upper end surface of the insulator 106 maintains a certain distance from the upper end surface of the cathode 105, and the upper end surface of the insulator 106 is lower than the upper end surface of the cathode 105; the lower end surface of the insulator 106 is flush with the upper end surface of the positioning step 111;

[0013] The anode 107 is formed by integrating three parts: a hemispherical discharge end, a thin solid cylinder and a thick solid cylinder; the head is the hemispherical discharge end, which protrudes upward from the upper end surface of the insulator 106 and is arranged near the jet hole 101; below the head is a thin solid cylinder, the diameter of which is equal to the diameter of the hemisphere of the head; below the thin solid cylinder is a thick solid cylinder, the diameter of which is larger than the diameter of the thin solid cylinder; the hemispherical discharge end of the anode 107 and the thick and thin solid cylinders are connected. The cylindrical rod is inserted from bottom to top into the large hole at the bottom of the insulator 106, and then passes through the hole into the small hole at the top of the insulator 106. A gap is left in the radial direction between the hemispherical discharge end of the anode 107 and the cathode 105. The outer wall of the anode 107 and the outer wall of the insulator 106 are smoothly connected. The air flow channel formed between the anode 107 and the cathode 105, and the air flow channel formed between the insulator 106 and the cathode 105 together constitute the air flow channel 108.

[0014] The semiconductor cyclone 109 consists of a hollow cylinder and a plurality of radially uniformly distributed fan-shaped blades fixed to the outside. The inner diameter of the hollow cylinder is equal to the outer diameter of the thin solid cylinder of the anode 107. The semiconductor cyclone 109 is fastened to the outer wall of the anode 107 through the hollow cylinder, thereby being embedded between the cathode 105 and the hemispherical head of the anode 107. It is axially located at the upper end of the insulator 106 but does not contact the insulator 106. The semiconductor cyclone 109 only blocks a small portion of the airflow channel 108.

[0015] In one embodiment of the present invention, the number of a group of air inlet holes 110 is 3 to 6; the diameter of the air inlet holes 110 is 1 to 5 mm; the distance between the first group of air inlet holes 110 and the end face of the igniter head is 15 to 40 mm; the distance between the second group of air inlet holes 110 and the end face of the igniter head is 30 to 60 mm; and the distance between the mounting thread 104 and the air inlet holes 110 is 60 to 180 mm.

[0016] In a specific embodiment of the present invention, the number of air inlet holes 110 in a group is 4; the diameter of the air inlet holes 110 is 2 mm; the distance between the first group of air inlet holes 110 and the end face of the igniter head is 20 mm; the distance between the second group of air inlet holes 110 and the end face of the igniter head is 35 mm; and the distance between the mounting thread 104 and the air inlet holes 110 is 80 mm.

[0017] In another embodiment of the present invention, the upper end surface of the insulator 106 is 10 to 40 mm away from the upper end surface of the cathode 105, and the outer diameter of the insulator 106 is 5 to 25 mm; the diameter of the hollow cylinder above the insulator 106 is 1 to 7 mm; and the diameter of the hollow cylinder below is 4 to 15 mm.

[0018] In another specific embodiment of the present invention, the upper end surface of the insulator 106 is 25 mm away from the upper end surface of the cathode 105, and the insulator 106 is made of alumina ceramic; the diameter of the hollow cylinder above the insulator 106 is 4 mm; the diameter of the hollow cylinder below is 9 mm.

[0019] In another embodiment of the present invention, the diameter of the hemispherical head of the anode 107 is 1 to 8 mm, and the maximum radial length of the long rod at the bottom is 4 to 10 mm; the radial gap between the hemispherical discharge end of the anode 107 head and the cathode 105 is 0.5 to 3 mm.

[0020] In another specific embodiment of the present invention, the anode 107 is made of nickel alloy, the diameter of the hemispherical head is 4 mm, and the maximum radial length of the bottom long rod is 7 mm; the radial gap between the hemispherical discharge end of the anode 107 head and the cathode 105 is 1.5 mm.

[0021] In another embodiment of the present invention, the outer diameter of the housing 102 is 20 to 30 mm; the inclination angle of the external air duct 103 is in the range of 15 to 80 degrees; the inner diameter of the external air duct 103 is 5 to 15 mm;

[0022] A flange is arranged at the external air bleed pipe 103, and the flange is coaxial with the igniter;

[0023] The diameter of the jet hole 101 is 6 to 12 mm;

[0024] The distance between the positioning step 111 and the tail end surface inside the cathode 105 is 2-5 mm.

[0025] In yet another specific embodiment of the present invention,

[0026] The outer diameter of the housing 102 is 25 mm; the inclination angle of the external air duct 103 is 60 degrees; the inner diameter of the external air duct 103 is 6 mm;

[0027] The semiconductor cyclone 109 blocks the air flow channel 108 at a center angle of no more than 10°, and the semiconductor cyclone 109 is made of ceramic with semiconductor properties;

[0028] The diameter of the jet hole 101 is 8 mm;

[0029] The distance between the positioning step 111 and the rear end surface inside the cathode 105 is 3 mm.

[0030] The working process of the above-mentioned low-voltage sliding arc igniter based on swirl semiconductor is as follows: the high voltage provided by the power system is connected to the anode 107 of the igniter through a cable, and the ground terminal of the power system and the cathode 105 are grounded; when power is turned on, since one end of the igniter semiconductor swirl 109 is in contact with the cathode 105 and the other end is in contact with the anode 108, the voltage across the two ends increases. The semiconductor swirl 109 is located in the gap between the cathode 105 and the anode 107. As the voltage across the cathode 105 and the anode 107 increases, the semiconductor swirl 109 is connected to the cathode 105 and the anode 107. Due to the low resistance characteristics of the body, flashover will occur randomly, thereby generating an arc-starting effect, so that the cathode 105 and the anode 107 start to arc from the flashover point; at the same time of arcing, external air is bleeded through the external air bleed pipe 103, and the air enters the air inlet channel 112 between the outer shell 102 and the cathode 105 through the external air bleed pipe 103, and then enters the air inlet hole 110, and then enters the air flow channel 108 for ignition, forming a sliding arc. Under the action of pneumatics, the sliding arc slides in the jet hole 101, and finally forms a sliding arc excitation output.

[0031] This invention integrates a semiconductor arc-starting device into the traditional sliding arc igniter. This device utilizes the low-voltage arc-starting characteristics of semiconductors to address the high-voltage breakdown requirement of existing sliding arc igniters. Furthermore, before achieving surface low-voltage arc-starting, the overall resistance of the semiconductor device is in the kilo-ohm range. Leveraging these unique advantages of semiconductors, the low-voltage sliding arc igniter based on swirl semiconductors can effectively reduce power supply design requirements, improve engineering practicality, and reduce the size and weight of power supply systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of a low-voltage sliding arc igniter based on a swirl semiconductor according to the present invention, wherein Figure 1 (a) shows a perspective view of the igniter, Figure 1 (b) shows a cross-sectional view of the igniter along the axial direction, Figure 1(c) shows an enlarged partial view of the igniter head. DETAILED DESCRIPTION

[0033] To achieve the above objectives, the present invention provides a low-voltage sliding arc igniter based on swirl semiconductors. Its technical feature is that the traditional air breakdown between electrodes is changed to semiconductor-assisted breakdown, so that the igniter is a resistive load before and after breakdown, which facilitates power supply design.

[0034] The present invention will be described in detail below with reference to the accompanying drawings.

[0035] See also Figure 1 The low-pressure sliding arc igniter based on swirl semiconductor of the present invention (hereinafter referred to as "igniter") consists of a jet hole 101, a shell 102, an external air duct 103, a mounting thread 104, a cathode 105, an insulator 106, an anode 107, an air flow channel 108, a semiconductor cyclone 109, an air inlet hole 110, a positioning step 111, an air inlet channel 112, etc.

[0036] Housing 102 is a hollow cylinder with an upper end face and a central hole formed to form a sliding arc. Internal threads are provided at the lower end of housing 102, which mate with mounting threads 104 for securement. Housing 102 should be larger than the overall internal dimensions, with an outer diameter of 20 to 30 mm, preferably 25 mm.

[0037] External air duct 103 is fixedly connected to housing 102 from the bottom, approximately above the internal threads of housing 102. External air duct 103 does not contact the internal threads of housing 102. External air duct 103 is inserted into housing 102 from bottom to top at an angle ranging from 15 to 80 degrees, preferably 60 degrees. Housing 102 has a hole at the entrance of external air duct 103 to allow for the introduction of external air through external air duct 103. The inner diameter of external air duct 103 is 5 to 15 mm, preferably 6 mm.

[0038] The disc near the external air duct 103 is a flange for docking and mounting. The flange is coaxial with the igniter. To ensure a secure connection between the external air duct 103 and the housing 102, a transition portion is formed where the flange meets the housing 102. This transition portion is a hollow, conical cone without a top or bottom. The cone is coaxial with the igniter. The circumference of the upper bottom of the cone is the same diameter as the outer circumference of the housing 102 and is fixedly connected. The circumference of the lower bottom of the cone is larger than the diameter of the lower bottom of the cone and is fixedly connected to the flange. For example, the transition portion can be welded to the housing 102 and the flange.

[0039] The cathode 105 is a hollow cylinder made of, for example, nickel alloy, with both ends open. The cathode 105 has a cylindrical exterior, and a gap is left between the outer wall of the cathode 105 and the inner wall of the housing 102 along the circumferential direction, which serves as an air inlet passage 112. Figure 1 (c) The inner cavity of cathode 105 is divided into three sections: head, middle, and tail. The inner cavity of cathode 105 gradually converges towards the head outlet, with the radius gradually decreasing. The diameter of the middle section of cathode 105 is smaller than that of the tail section, and a step is naturally formed between the middle and tail sections to accommodate the shape of insulator 106. A positioning step 111 is machined at an appropriate position at the tail section of cathode 105 to hold in place insulator 106. Positioning step 111 is 2-5 mm, preferably 3 mm, from the end face of the tail section of cathode 105. The lower end face of positioning step 111 maintains a certain distance from the lower end face of cathode 105.

[0040] The through hole in the inner cavity of the cathode 105 near the head of the cathode 105 is a jet hole 101, and the diameter of the jet hole 101 is 6 to 12 mm, preferably 8 mm. The jet hole 101 is also a through hole in the head of the shell 102.

[0041] Mounting threads 104, such as M15, are machined at appropriate locations on the rear end of cathode 105 for threaded connection with the internal threads of housing 102. Mounting threads 104 are located below air inlet 110 and spaced a certain distance apart; the distance between mounting threads 104 and air inlet 110 is approximately 60 to 180 mm, preferably 80 mm.

[0042] Two groups of air inlet holes 110 are arranged in the middle of the inner cavity of the cathode 105 near the head, one above and one below. Each group of air inlet holes includes multiple air inlet holes evenly distributed along the circumference. These air inlet holes are through holes that penetrate the inner and outer walls of the cathode 105. The air inlet holes 110 are connected to the air inlet channel 112, the air flow channel 108 (described below) and the jet hole 101. The number of air inlet holes 110 in a group is usually 3 to 6, preferably 4. The diameter of the air inlet holes 110 is 1 to 5 mm, preferably 2 mm. The air inlet holes 110 are located above the mounting thread 104. The distance between the first group of air inlet holes 110 and the end face of the igniter head is 15 to 40 mm, preferably 20 mm; the distance between the second group of air inlet holes 110 and the end face of the igniter head is 30 to 60 mm, preferably 35 mm. The air inlet 110 is used to provide a gas source for the sliding arc, ensuring that the secondary flow of the combustion chamber enters the jet hole 101 through the air inlet 110, driving the arc to slide and form sliding arc plasma.

[0043] The insulator 106 is a hollow structure located between the cathode 105 and the anode 107 and has a rotationally symmetrical structure around the axis of the igniter. The outer wall of the insulator 106 is divided into three cylindrical structures: upper, middle and lower sections, and the diameter increases from top to bottom; the outer wall of the upper cylinder maintains a certain distance from the inner wall of the cathode 105, and the gap in between is used to generate an arc; the middle cylinder protrudes outward to form a boss adjacent to the upper cylinder, and the boss is located below the two groups of air inlet holes 110, and is in an interference fit state with the inner wall surface of the middle part of the inner cavity of the cathode 105 (it can also be understood that the inner diameter of the cathode 105 is equal to the outer diameter of the boss), and, between below the boss of the middle cylinder and the lower cylinder, a cavity is formed between the outer wall of the insulator 106 and the inner wall of the cathode 105, and this cavity is not connected to the air of the air inlet hole 110 (it can be understood that this is for the purpose of reducing material weight); the step formed at the junction of the middle cylinder and the lower cylinder corresponds to the shape of the step formed between the middle and tail of the cathode 105, so that the lower cylinder is in close contact with the inner wall of the cathode 105. The internal cavity of insulator 106 forms two hollow cylindrical structures of different diameters. The upper hollow cylinder has a smaller diameter than the lower hollow cylinder. Together, they form a through-hole for mounting anode 107. The upper end surface of insulator 106 maintains a certain distance from the upper end surface of cathode 105, and the upper end surface of insulator 106 is lower than the upper end surface of cathode 105, leaving sufficient space below the air inlet 110 for the semiconductor cyclone to develop. The upper end surface of insulator 106 is 10 to 40 mm from the upper end surface of cathode 105, preferably 25 mm. The lower end surface of insulator 106 is flush with the upper end surface of positioning step 111. The outer diameter of insulator 106 is 5 to 25 mm. As mentioned above, the outer diameter of insulator 106 varies from top to bottom and should be selected based on actual needs. During the selection process, attention should be paid to the coordination with the inner diameter of cathode 105. Insulator 106 can be made of, for example, aluminum oxide ceramic. The diameter of the hollow cylinder above the insulator 106 is 1 to 7 mm, preferably 4 mm; the diameter of the hollow cylinder below the insulator 106 is 4 to 15 mm, preferably 9 mm.

[0044] The anode 107 is a metal electrode made of nickel alloy, for example, and is integrally formed by a hemispherical discharge end, a thin solid cylinder, and a thick solid cylinder; or Figure 1As shown in (b), the head is a hemispherical discharge end, located near the jet orifice 101; below the head is a thin solid cylinder with a diameter equal to the diameter of the hemisphere of the head; below the thin solid cylinder is a thick solid cylinder with a larger diameter than the thin solid cylinder. In practical applications, the anode 107, excluding the hemispherical head, consists of a solid cylindrical rod. The cross-section is not limited to circular, but preferably circular, but must be centrally symmetrical. In one embodiment of the present invention, the diameter of the hemisphere of the head is 1 to 8 mm, preferably 4 mm, and the maximum radial length of the cylindrical rod at the bottom is 4 to 10 mm, preferably 7 mm. The hemispherical discharge end and the thick and thin solid cylindrical rod of the anode 107 are inserted from bottom to top into the large hole at the bottom of the insulator 106, passing through the hole and into the small hole at the top of the insulator 106. The external wiring is inserted from the outside to the inside and connected to the lower end of the anode 107. The hemispherical discharge end of the anode 107 must ensure a radial gap with the cathode 105, which is generally 0.5 to 3 mm, preferably 1.5 mm. A smooth connection is formed between the outer wall of the anode 107 and the outer wall of the insulator 106. The air flow channel formed between the anode 107 and the cathode 105, and the air flow channel formed between the insulator 106 and the cathode 105 together constitute the air flow channel 108. The air inlet 110 is a cylindrical through hole, and the external air is bleed through the external air bleed pipe 103. The bleed air enters the air inlet channel 112 between the outer shell 102 and the cathode 105 through the external air bleed pipe 103, and then enters the air inlet 110 and then the air flow channel 108 for ignition, forming a sliding arc. Finally, the sliding arc develops from the jet hole 101 to the outside of the igniter.

[0045] The semiconductor cyclone 109 consists of a hollow cylinder with multiple radially evenly distributed fan-shaped blades fixed to its exterior. Cyclones 109 are well known to those skilled in the art. The present invention uses semiconductor materials to fabricate cyclone 109, aiming to leverage the low-voltage arc-starting properties of semiconductors to address the high-voltage breakdown requirements of existing sliding arc igniters. The inner diameter of the hollow cylinder is equal to the outer diameter of the thin solid cylinder of anode 107. Semiconductor cyclone 109 is securely mounted to the outer wall of anode 107 through the hollow cylinder, thereby embedding itself between cathode 105 and the hemispherical head (i.e., discharge end) of anode 107. It is axially positioned above insulator 106 but does not contact it. Semiconductor cyclone 109 blocks only a small portion of airflow channel 108, preferably with a center angle of no more than 10°. The center of the circle is the center of the circle formed by the inner wall of cathode 105. The material of the semiconductor cyclone 109 can be selected from ceramics with semiconductor properties such as zinc oxide and silicon carbide. Its main function is to transform the original air gap into a semiconductor connection and change the impedance characteristics at the breakdown moment. Figure 1 The semiconductor cyclone 109 shown in the figure appears asymmetrical due to the cross-sectional view, but this is a representation of the actual situation.

[0046] The igniter operates as follows: The high voltage provided by the power system is connected to the igniter's anode 107 via a cable, and the power system ground terminal and cathode 105 are grounded. When power is applied, the voltage across the igniter's semiconductor cyclone 109 increases because one end contacts the cathode 105 and the other contacts the anode 107. The semiconductor cyclone 109 is located in the gap between the cathode 105 and the anode 107. During ignition, flashovers occur randomly, generating an arc strike, causing the cathode 105 and anode 107 to arc from the flashover point. Simultaneously with arcing, external air is introduced through the external air bleed pipe 103. The air then enters the air inlet channel 112 between the housing 102 and the cathode 105, then enters the air inlet port 110, and then enters the air flow channel 108, igniting the ignition and forming a sliding arc. Under the action of pneumatics, the sliding arc slides within the jet hole 101, ultimately forming a sliding arc excitation output.

[0047] To address the power supply design challenges posed by the large impedance variations during operation of existing sliding arc igniters, this invention proposes a low-voltage sliding arc igniter using swirl current semiconductors. This igniter integrates a semiconductor arc-starting device into the traditional sliding arc igniter, leveraging the low-voltage arc-starting properties of semiconductors to overcome the high-voltage breakdown requirements of existing sliding arc igniters. Leveraging the unique advantages of semiconductor devices, this device reduces power supply design requirements, improves engineering practicality, and ultimately reduces the size and weight of the power supply system.

Claims

1. A low-voltage sliding arc igniter based on swirl semiconductor, characterized in that: It includes a jet hole (101), a shell (102), an external air duct (103), a mounting thread (104), a cathode (105), an insulator (106), an anode (107), an air flow channel (108), a semiconductor cyclone (109), an air inlet hole (110), a positioning step (111), and an air inlet channel (112); wherein The outer shell (102) is in the shape of a hollow cylinder as a whole, and has an upper end face with a hole punched in the center of the end face; an internal thread is provided at the lower end of the inner portion of the outer shell (102), and the internal thread is fixedly matched with the mounting thread (104); The external air bleed pipe (103) is fixedly connected to the outer shell (102) from the lower part of the outer shell (102) and near the upper part of the inner thread of the outer shell (102). The external air bleed pipe (103) does not contact the inner thread of the outer shell (102). The external air bleed pipe (103) is inserted into the outer shell (102) obliquely from bottom to top. The outer shell (102) is punched with a hole at the introduction point of the external air bleed pipe (103) to introduce external air through the external air bleed pipe (103). The cathode (105) is a hollow cylinder with open ends. The exterior of the cathode (105) is cylindrical. A gap is left between the outer wall of the cathode (105) and the inner wall of the shell (102) along the circumferential direction to form an air inlet channel (112). The inner cavity of the cathode (105) is divided into three sections: the head, the middle, and the tail. The inner cavity of the head of the cathode (105) gradually converges toward the head outlet, and the radius gradually decreases. The diameter of the middle part of the inner cavity of the cathode (105) is smaller than the diameter of the tail, and a step is naturally formed in the middle. A positioning step (111) is processed at the tail inside the cathode (105) to clamp the insulator (106). The lower end surface of the positioning step (111) maintains a certain distance from the lower end surface of the cathode (105). The through hole in the inner cavity of the cathode (105) close to the head and the through hole in the head of the shell (102) together form a jet hole (101); A mounting thread (104) is processed on the tail of the cathode (105); the mounting thread (104) is located below the air inlet (110) and maintains a certain distance from the air inlet (110); Two groups of air inlet holes (110) are arranged in the middle of the inner cavity of the cathode (105) near the head, one above and one below. Each group of air inlet holes includes a plurality of air inlet holes evenly distributed along the circumference. These air inlet holes are all through holes that penetrate the inner and outer walls of the cathode (105). The air inlet holes (110) are in communication with the air inlet channel (112), the air flow channel (108) and the jet hole (101). The insulator (106) is a hollow structure located between the cathode (105) and the anode (107), and has a rotationally symmetrical structure around the axis of the igniter; the outer wall of the insulator (106) is divided into three cylindrical structures: upper, middle and lower, with the diameter increasing from top to bottom; the outer wall of the upper cylinder maintains a certain distance from the inner wall of the cathode (105); the middle cylinder protrudes outwards to form a boss adjacent to the upper cylinder, and the boss is located below the two groups of air inlet holes (110) and is in an interference fit state with the inner wall of the middle part of the cathode (105); the junction of the middle cylinder and the lower cylinder forms a boss. The formed step corresponds to the shape of the step formed between the middle and tail of the cathode (105), so that the lower cylinder is in close contact with the inner wall of the cathode (105); the internal cavity of the insulator (106) forms two hollow cylindrical structures with different diameters, the diameter of the upper hollow cylindrical structure is smaller than that of the lower hollow cylindrical structure, and the two together form a through hole; the upper end surface of the insulator (106) maintains a certain distance from the upper end surface of the cathode (105), and the upper end surface of the insulator (106) is lower than the upper end surface of the cathode (105); the lower end surface of the insulator (106) is flush with the upper end surface of the positioning step (111); The anode (107) is formed by integrating three parts: a hemispherical discharge end, a thin solid cylinder and a thick solid cylinder; the head is the hemispherical discharge end, which protrudes upward from the upper end surface of the insulator (106) and is arranged close to the jet hole (101); below the head is a thin solid cylinder, the diameter of which is equal to the diameter of the hemisphere of the head; below the thin solid cylinder is a thick solid cylinder, the diameter of which is larger than the diameter of the thin solid cylinder; the hemispherical discharge end of the anode (107) and the thick and thin solid cylinders are connected from bottom to top. The anode (107) is inserted into the large hole at the bottom of the insulator (106) and passes through the hole to enter the small hole at the top of the insulator (106); a gap is left in the radial direction between the hemispherical discharge end of the anode (107) and the cathode (105); a smooth connection is formed between the outer wall surface of the anode (107) and the outer wall surface of the insulator (106); the air flow channel formed between the anode (107) and the cathode (105) and the air flow channel formed between the insulator (106) and the cathode (105) together constitute an air flow channel (108); The semiconductor cyclone (109) is composed of a hollow cylinder and a plurality of radially uniformly distributed fan-shaped blades fixed outside the hollow cylinder. The inner diameter of the hollow cylinder is equal to the outer diameter of the thin solid cylinder of the anode (107). The semiconductor cyclone (109) is fixedly mounted on the outer wall of the anode (107) through the hollow cylinder, thereby being embedded between the cathode (105) and the hemispherical head of the anode (107). The semiconductor cyclone (109) is axially located at the upper end of the insulator (106) but does not contact the insulator (106). The semiconductor cyclone (109) only blocks a small part of the airflow channel (108).

2. The low-voltage sliding arc igniter based on swirl semiconductor according to claim 1, characterized in that: The number of a group of air inlet holes (110) is 3 to 6; the diameter of the air inlet holes (110) is 1 to 5 mm; the distance between the first group of air inlet holes (110) and the end face of the igniter head is 15 to 40 mm; the distance between the second group of air inlet holes (110) and the end face of the igniter head is 30 to 60 mm; and the distance between the mounting thread (104) and the air inlet holes (110) is 60 to 180 mm.

3. The low-voltage sliding arc igniter based on swirl semiconductor according to claim 2, characterized in that: The number of the air inlet holes (110) in a group is 4; the diameter of the air inlet holes (110) is 2 mm; the distance between the first group of air inlet holes (110) and the end face of the igniter head is 20 mm; the distance between the second group of air inlet holes (110) and the end face of the igniter head is 35 mm; and the distance between the mounting thread (104) and the air inlet holes (110) is 80 mm.

4. The low-voltage sliding arc igniter based on swirl semiconductor according to claim 1, characterized in that: The upper end surface of the insulator (106) is 10 to 40 mm away from the upper end surface of the cathode (105), and the outer diameter of the insulator (106) is 5 to 25 mm; the diameter of the hollow cylinder above the insulator (106) is 1 to 7 mm; and the diameter of the hollow cylinder below the insulator (106) is 4 to 15 mm.

5. The low-voltage sliding arc igniter based on swirl semiconductor according to claim 4, characterized in that: The upper end face of the insulator (106) is 25 mm away from the upper end face of the cathode (105), and the insulator (106) is made of aluminum oxide ceramics; the diameter of the hollow cylinder above the insulator (106) is 4 mm; the diameter of the hollow cylinder below the insulator (106) is 9 mm.

6. The low-voltage sliding arc igniter based on swirl semiconductor according to claim 1, characterized in that: The diameter of the hemispherical head of the anode (107) is 1 to 8 mm, and the maximum radial length of the long rod at the bottom is 4 to 10 mm. The radial gap between the hemispherical discharge end of the anode (107) head and the cathode (105) is 0.5 to 3 mm.

7. The low-voltage sliding arc igniter based on swirl semiconductor according to claim 6, characterized in that: The anode (107) is made of nickel alloy, the diameter of the hemispherical head is 4mm, and the maximum radial length of the long rod at the bottom is 7mm; the radial gap between the hemispherical discharge end of the anode (107) head and the cathode (105) is 1.5mm.

8. The low-voltage sliding arc igniter based on swirl semiconductor according to claim 1, characterized in that: The outer diameter of the housing (102) is 20 to 30 mm; the inclination angle of the external air duct (103) ranges from 15 to 80 degrees; the inner diameter of the external air duct (103) is 5 to 15 mm; A flange is arranged at the external air bleed pipe (103), wherein the flange is coaxial with the igniter; The diameter of the jet hole (101) is 6 to 12 mm; The distance between the positioning step (111) and the tail end surface inside the cathode (105) is 2-5 mm.

9. The low-voltage sliding arc igniter based on swirl semiconductor according to claim 8, characterized in that: The outer diameter of the housing (102) is 25 mm; the inclination angle of the external air duct (103) is 60 degrees; the inner diameter of the external air duct (103) is 6 mm; The center angle of the semiconductor cyclone (109) blocking the airflow channel (108) does not exceed 10 degrees, and the material of the semiconductor cyclone (109) is ceramic with semiconductor properties; The diameter of the jet hole (101) is 8 mm; The distance between the positioning step (111) and the tail end surface inside the cathode (105) is 3 mm.

10. The low-voltage sliding arc igniter based on swirl semiconductor according to any one of claims 1 to 9, characterized in that: The working process of the igniter is as follows: the high voltage provided by the power system is connected to the anode (107) of the igniter through a cable, and the ground terminal of the power system and the cathode (105) are grounded; when the power is turned on, since one end of the igniter semiconductor cyclone (109) is in contact with the cathode (105) and the other end is in contact with the anode (107), the voltage at both ends increases. The semiconductor cyclone (109) is located in the gap between the cathode (105) and the anode (107). As the voltage between the cathode (105) and the anode (107) increases, due to the low resistance characteristics of the semiconductor, A flashover phenomenon will randomly occur, thereby generating an arcing effect, so that the cathode (105) and the anode (107) start to arc from the flashover point; while arcing, external air is bleed through the external air bleed pipe (103), and the air enters the air inlet channel (112) between the shell (102) and the cathode (105) through the external air bleed pipe (103), and then enters the air inlet hole (110), and then enters the air flow channel (108) for ignition, forming a sliding arc. Under the action of pneumatics, the sliding arc slides in the jet hole (101), and finally forms a sliding arc excitation output.

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