Intelligent torch ignition device based on high-frequency induction heating

Abstract

The invention belongs to the technical field of automatic control, and particularly relates to an intelligent torch ignition device based on high-frequency induction heating, which comprises an eddy current heating part used for arranging a high-frequency coil in an ignition area, generating an alternating magnetic field through the high-frequency coil, triggering eddy current in a metal chip or a metal catalytic body in a torch and carrying out induction heating, therefore, a high-density heat source is formed; the critical temperature rise judging part is used for judging whether the temperature of the mixed gas exceeds the critical temperature or not when the mixed gas is heated due to the radiation and heat conduction effects of the metal chip or the metal catalytic body; the high-frequency ionization part is used for executing electric field excitation and maximizing plasma forming efficiency; and the fire core self-sustaining control part is used for calculating the fire core radius in real time, and if the fire core radius does not reach a self-sustaining threshold value, induction heating and electric field excitation are continued. The response speed, the ignition success rate and the environment adaptability of the ignition system are remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of automatic control, and particularly relates to an intelligent torch ignition device based on high-frequency induction heating. Background Art

[0002] In current industrial and civil gas systems, torch ignition, as a common ignition means, is widely used in gas boilers, chemical tail gas incineration, gas thermal energy devices, and environmental protection combustion systems. Traditional torch ignition methods can be roughly divided into mechanical ignition, spark ignition, piezoelectric ignition, and high-energy electron ignition, etc. Among them, spark ignition and piezoelectric ignition are widely adopted due to their simple structure and low cost. However, these conventional methods show obvious deficiencies under complex working conditions. For example, in scenarios with high humidity, low temperature, severe wind disturbance, or large fluctuations in gas concentration, problems such as low ignition success rate, slow response speed, and short equipment life frequently occur, resulting in a decline in the operating efficiency of the entire combustion system and even potential safety hazards.

[0003] In addition to the limitations of the hardware structure, there are also significant shortcomings in the ignition process control strategy of the existing technology. On the one hand, most ignition systems only use a single physical quantity such as temperature, voltage, or current as the ignition criterion, lacking a comprehensive judgment mechanism for gas components, ionization degree, and thermal field state, resulting in excitation being performed outside the optimal ignition window, with high energy consumption and low success rate. On the other hand, most existing systems are in an open-loop control mode, lacking the ability of adaptive adjustment after ignition failure, and unable to dynamically adjust heating parameters, ionization time, or excitation amplitude to cope with environmental disturbances and gas fluctuations. These defects in the control strategy make it difficult for the existing technology to meet the comprehensive requirements of modern gas applications for intelligence, high reliability, and multi-adaptability. Summary of the Invention

[0004] In view of this, the main purpose of the present invention is to provide an intelligent torch ignition device based on high-frequency induction heating. By introducing a non-contact induction heat source and a plasma control mechanism, the response speed, ignition success rate, and environmental adaptability of the ignition system are significantly improved.

[0005] The technical solution adopted by the present invention is as follows: Intelligent torch ignition device based on high-frequency induction heating, the device comprising: an eddy current heating part for arranging a high-frequency coil in the ignition area, generating an alternating magnetic field through the high-frequency coil, inducing eddy currents in the metal chip or metal catalytic body inside the torch, and performing induction heating to form a high-density heat source; a critical temperature rise discrimination part for discriminating whether the temperature of the mixed gas exceeds the critical temperature when the mixed gas is heated by the radiation and heat conduction of the metal chip or metal catalytic body; a high-frequency ionization part for estimating the electron density in the mixed gas when the temperature of the mixed gas exceeds the critical temperature, comparing the electron density with the ionization threshold, and if the electron density exceeds the ionization threshold, performing electric field excitation to maximize the plasma formation efficiency; a fire core self-sustaining control part for constructing a fire core radius expansion function, calculating the fire core radius in real time, and if the fire core radius reaches the self-sustaining threshold, determining that the fire core can reach self-sustaining, then sequentially stopping induction heating and electric field excitation, and if the fire core radius does not reach the self-sustaining threshold, continuing induction heating and electric field excitation.

[0006] Further, the metal chip or metal catalytic body is located at the geometric center of the high-frequency coil, and the axial distance between the heating surface or the center point of the metal chip or metal catalytic body and the cross-sectional plane of the high-frequency coil is in the range of one-fourth to one-half of the radius of the high-frequency coil to maximize the magnetic flux coupling.

[0007] Further, the ignition area is a spherical area formed with a radius 2 to 3 times that of the metal chip or metal catalytic body; the flow rate of the mixed gas is less than 0.5 m / s.

[0008] Further, at the moment the temperature of the mixed gas is as: ; wherein, is the initial ambient temperature, in units of K; is the heat radiation and conduction efficiency, with a value range of 0.2 to 0.6; is the instantaneous power of induction heating, in units of W; is the effective area of direct contact between the metal chip or metal catalytic body and the mixed gas, in units of m²; is the density of the mixed gas, in units of kg / m³; is the specific heat capacity at constant pressure of the mixed gas, in units of J / (kg·K); is the volume of the ignition area; is the heat conduction time constant, controlling the temperature rise rate, with a value range of 5 ms to 100 ms.

[0009] Further, the instantaneous power of induction heating is: ; Among them, is the conductivity of the metal chip or the metal catalyst, with the unit of S / m; is the angular frequency of the alternating magnetic field, with the unit of rad / s; is the peak magnetic induction intensity of the high-frequency coil, with the unit of T; is the radius of the metal chip or the metal catalyst, with the unit of m; is the eddy current penetration depth, with the unit of m; , among which, is the magnetic permeability of the material of the metal chip or the metal catalyst, with the unit of H / m; is the conductivity of the metal chip or the metal catalyst, with the unit of S / m.

[0010] Furthermore, the heat conduction time constant is: ; Among them, is the heat transfer coefficient between the metal chip or the metal catalyst and the gas, with the value range of 50 to 200, and the unit of W / (m²·K).

[0011] Furthermore, at the moment the electron density in the mixed gas is: ; Among them, is the vacuum permittivity, with the value of 8.854×10 -12 , and the unit of F / m; is the electric field strength of the high-frequency coil, with the unit of V / m; is the neutral gas molecular density, with the unit of m -3 ; is the average collision frequency; is the electron mobility, with the unit of m² / (V·s); is the Planck constant; is the equivalent plasma frequency induced by the high-frequency coil, with the unit of Hz; is the nonlinear ionization damping coefficient of the gas medium, with the unit of Pa -1 ; is the static pressure of the mixed gas; is the ionization cross-section, with the unit of m², indicating the probability of a single electron ionizing neutral particles per unit time.

[0012] Furthermore, at the moment the fire kernel radius is: ; Among them, is the initial fire kernel radius, with a value range of 1 to 3, and the unit is mm; is the flame propagation enhancement coefficient, which represents the increase in the fire kernel expansion rate caused by vortex or heat diffusion; is the thermal conductivity of the mixed gas, with the unit of W / (m·K); is the autoignition temperature of the mixed gas; is the heat release of combustion per unit mass of the mixed gas.

[0013] Furthermore, the critical temperature is the autoignition temperature of the mixed gas ; Let the ionization threshold be ; When and , electric field excitation is executed; When the mixed gas is a mixture of methane and air, The value range of is ; When the mixed gas is a mixture of propane and air, The value range of is ; When the mixed gas is a mixture of oxygen and hydrogen, The value range of is .

[0014] Adopting the above technical solutions, the present invention has the following beneficial effects: By introducing a non-contact induction heat source and a plasma control mechanism, the response speed, ignition success rate, and environmental adaptability of the ignition system are significantly improved. Compared with traditional spark discharge or mechanical ignition methods, this device does not require electrode contact, not only eliminating problems such as short lifespan caused by electrode wear and erosion, but also effectively avoiding electrical fires or uneven ignition phenomena. By rapidly forming a concentrated heat source in a metal chip or catalytic body through high-frequency induction, the gas in the ignition area can be heated above the autoignition threshold in an extremely short time, ensuring the immediacy and controllability of the ignition process. In addition, the system integrates a dual-criterion model based on electron density and gas temperature, enabling the ionization excitation action to be triggered only at the optimal timing, avoiding energy waste and enhancing discharge efficiency. After ignition is completed, the system further determines whether the fire kernel has self-sustaining ability based on the flame front expansion model. If the requirements are not met, secondary ignition compensation is automatically performed to achieve closed-loop intelligent control throughout the process. The present invention supports adaptive ignition strategies for various gas types, can automatically adjust the criterion thresholds according to the type of fuel gas, has high versatility and reliability, and is applicable to industrial gas ignition, chemical tail gas incineration, and distributed heat energy control in complex working conditions, etc., with significant engineering application value and promotion prospects. Description of the Drawings

[0015] Figure 1 is the schematic diagram of the device structure of the intelligent torch ignition device based on high-frequency induction heating provided by the embodiment of the present invention. Detailed implementation mode

[0016] All features disclosed in this specification, or steps in all methods or processes disclosed, except for mutually exclusive features and / or steps, can be combined in any way.

[0017] Any feature disclosed in this specification (including any additional claims, abstract) can be replaced by other equivalent or similar-purpose alternative features unless specifically stated. That is, unless specifically stated, each feature is only an example of a series of equivalent or similar features.

[0018] Example 1, refer to Figure 1 : An intelligent torch ignition device based on high-frequency induction heating, the device includes: an eddy current heating part, used to arrange a high-frequency coil in the ignition area, generate an alternating magnetic field through the high-frequency coil, and induce eddy currents in the metal chip or metal catalytic body inside the torch to perform induction heating, thereby forming a high-density heat source; a critical temperature rise discrimination part, used to discriminate whether the temperature of the mixed gas exceeds the critical temperature when the mixed gas is heated by the radiation and heat conduction of the metal chip or metal catalytic body; a high-frequency ionization part, used to estimate the electron density in the mixed gas when the temperature of the mixed gas exceeds the critical temperature, compare the electron density with the ionization threshold, and if the electron density exceeds the ionization threshold, perform electric field excitation to maximize the plasma formation efficiency; a fire core self-sustaining control part, used to construct a fire core radius expansion function, calculate the fire core radius in real time, if the fire core radius reaches the self-sustaining threshold, it is judged that the fire core can reach self-sustaining, and then stop the induction heating and electric field excitation in turn, if the fire core radius does not reach the self-sustaining threshold, continue the induction heating and electric field excitation.

[0019] The eddy current heating part is based on high-frequency electromagnetic induction technology. By configuring a high-frequency excitation coil in the ignition area, an alternating magnetic field is generated after the coil is energized with high-frequency alternating current. This magnetic field penetrates the conductive metal body or metal catalytic chip located at its center, and then induces a circular induction current, that is, eddy current, inside the chip. When the induction current flows inside the chip, due to the resistance property of the chip itself, a Joule heat effect is generated, causing the inside of the chip to heat up rapidly, forming a high-temperature local heat source area. This high-density heat source not only has the ability to instantaneously increase the temperature, but also can efficiently radiate and conduct heat to the surrounding space, providing a physical basis for subsequent gas temperature rise and ionization reactions. The entire eddy current heating process has three characteristics: non-contact, fast response, and high local energy concentration, and is suitable for torch ignition scenarios with limited space, complex environments, and high ignition accuracy requirements.

[0020] The eddy current heating part mainly consists of three parts: The first part is the high-frequency inverter power supply module, which is used to generate stable and adjustable high-frequency electrical signals and input them into the coil system; the second part is the induction coil structure, which adopts a spiral or planar disk-shaped coil layout form, and the size and number of turns are optimized according to the chip geometry and the torch cavity size, so as to achieve precise control of the magnetic flux density and spatial magnetic field distribution; the third part is the metal chip or metal catalyst body located at the geometric center or focal area of the coil, and its material is usually selected from high-conductivity and high-heat-resistance metal materials such as copper, nickel or their alloys to enhance the eddy current response effect and avoid structural damage of the material at high temperatures. When the eddy current heating part works, the high-frequency current forms a spatial magnetic flux in the excitation coil. After the magnetic flux penetrates the chip volume, a closed-loop eddy current path is induced in it. The current distribution shows the surface skin effect, and the heat is concentrated in the surface to shallow area of the chip. The chip surface temperature can be raised to more than a thousand degrees Celsius in a very short time, thus forming an effective ignition heat source area.

[0021] To ensure the stable operation of the system under actual working conditions, a number of engineering protection and adjustment mechanisms are also embedded in the eddy current heating part. In terms of structure, a high-temperature resistant ceramic insulation support is provided between the coil and the chip to avoid thermal degradation of the coil insulation layer caused by heat diffusion or thermal radiation; in terms of electronic control, the inverter power supply system has a power adjustable function, which can adapt the output frequency and voltage according to variables such as ambient temperature and gas concentration, so as to achieve closed-loop control of the induction power; in terms of safety protection, a temperature sensor and a timing logic unit are also set. If the chip temperature continues to rise but no ignition phenomenon occurs, the system will automatically determine it as a thermal failure state and execute power reduction or shutdown instructions to prevent the device from overheating damage. In addition, the layout form of the eddy current heating structure also takes into account the gas flow characteristics of the torch cavity to ensure that the heating area and the gas main flow area have a good heat exchange contact surface, so as to maximize the thermal coupling efficiency of the chip heat energy to the mixed gas.

[0022] The critical temperature rise discrimination part undertakes the intermediate logical function connecting heat source excitation and plasma formation, and is the key control node for judging whether the mixed gas reaches the flammable critical state. Its working principle is based on the basic knowledge of autoignition limits in gas combustion theory. By real-time monitoring, evaluating, and comparing the temperature of the mixed gas, it determines whether it exceeds a certain physical critical value, thereby deciding whether to activate the subsequent high-frequency ionization module. In the actual structural design, this part integrates a temperature sensing unit, a threshold discrimination unit, and a logic control unit, and forms a physical and signal-level coupling with the pre-stage eddy current heating part to constitute a complete heat judgment and execution chain. The mixed gas is in close contact with the metal chip or metal catalyst in the torch cavity. When the chip surface is excited to a high temperature by high-frequency induction, heat acts on the surrounding gas-air mixture through both radiation and conduction paths, causing its temperature to rise rapidly. During this process, the temperature sensing unit captures the transient temperature changes of the gas in the mixing zone at a fixed sampling frequency, and the data is transmitted to the threshold discrimination module in real time. The discrimination module then makes a comparison based on the preset critical temperature value.

[0023] The setting of the critical temperature is not arbitrary but determined by the type of gas used in the torch. Different gases have different autoignition points. For example, the autoignition temperatures of methane, propane, and hydrogen are different. Therefore, when the system leaves the factory, it is necessary to select the corresponding critical parameters according to the gas composition and solidify them in the control module. If the system is a programmable platform, it can realize the dynamic assignment of the critical temperature corresponding to different gas switches, further improving the versatility and adaptability of the device. When the discrimination module receives the real-time temperature value from the sensor, it makes a logical judgment based on the deviation between this value and the critical temperature. If the current temperature has not reached the gas autoignition limit, the system remains in a waiting state while maintaining the continuous action of induction heating to promote further heating of the chip and enhance its thermal excitation ability for the gas. When it is determined that the temperature reaches or exceeds the critical threshold, the system automatically sends a signal to activate the high-frequency ionization part to prepare for the next stage of electron density evaluation and plasma generation. During this process, the temperature discrimination module not only acts as a logic controller but also undertakes a safety guarantee function, that is, when the temperature cannot reach the critical point for a long time or the temperature rise rate is significantly lower than the expected value, the system can trigger the fault diagnosis function through the temperature discrimination module to judge whether there are abnormal situations such as insufficient gas concentration, decreased chip induction efficiency, or blocked heating path, and take corresponding protection measures.

[0024] Since torch ignition usually occurs within an extremely short time and the slope of temperature change is very large, the selected sensor must have high sensitivity, high-frequency response, and high-temperature resistance capabilities. Commonly used devices include micro-thermocouples, infrared non-contact thermometers, or thermistor arrays. In addition, the position where the sensor is arranged must be close to the main gas heating area, and at the same time, it cannot be directly exposed to the high-temperature radiation center of the chip to avoid damage or reading distortion. Therefore, an isothermal stable point 2 to 5 millimeters away from the chip is usually selected as the sampling reference. After the temperature data is collected, it needs to undergo primary filtering and digital smoothing processing to exclude spike noise caused by instantaneous air flow disturbances or electromagnetic interference and ensure the stability of the discriminant logic input. At the same time, the threshold discriminant logic needs to have a certain tolerance mechanism, that is, it allows instantaneous temperature fluctuations within a reasonable range not to trigger false judgments to prevent frequent startup or shutdown of the subsequent ionization module due to minor jitters when the temperature approaches the critical point. The overall response time of the system is usually controlled between dozens of milliseconds and hundreds of milliseconds to meet the dual requirements of response speed and reliability for industrial torch ignition.

[0025] The high-frequency ionization part constitutes the key physical module for realizing ignition conversion. Its core function is to induce the outer-layer electrons of molecules or atoms in the gas to be stripped after the mixed gas is heated to the critical temperature by applying a high-frequency electric field, thereby generating a certain density of free electrons to form plasma seeds and providing the basic electron density support for the formation of the flame kernel. This process depends on the collision mechanism and energy transfer law between electrons and neutral molecules at the microscale, and its principle can be attributed to the balance between the excitation ability of the high-frequency field on gas molecules and the critical free electron density required for plasma formation. When the temperature of the mixed gas has reached the self-ignition critical point but combustion has not occurred naturally, introducing a high-frequency electric field at this time can effectively improve the energy state of free electrons, enabling them to have sufficient ionization kinetic energy when colliding with neutral particles, thereby breaking the molecular bond structure and releasing new electrons from it to achieve a multi-stage electron cascade reaction, and finally constructing a stable ionization core area in space. This area is the seed area of the flame kernel. If the electron density and spatial size are sufficient, it can further stimulate the entire combustion reaction chain and enter the self-sustaining combustion stage.

[0026] The physical structure of the high-frequency ionization section includes an electric field excitation device, an ionization parameter calculation unit, and an ionization discrimination control logic, etc. Its working timing is determined by the pre-set critical temperature rise discrimination module. Once it is confirmed that the temperature of the mixed gas exceeds the set spontaneous ignition point of the fuel gas, the system triggers the ionization module to turn on, and applies a voltage signal of dozens of megahertz to the set electrode group or secondary induction coil inside the torch cavity through the high-frequency power module, generating a spatially uniformly distributed high-frequency alternating electric field. This electric field is superimposed on the original induction heating coil field to form a composite electromagnetic excitation system, enhancing the electron motion acceleration effect. Under the action of this electric field, some electrons in the gas gain increased kinetic energy and trigger the secondary electron release effect during multiple collisions, gradually increasing the free electron density in the gas region. In order to monitor the ionization state in the gas in real time, the ionization parameter calculation unit estimates the electron density, and this estimation is based on the pre-set ionization characteristics of the gas medium, the current gas temperature, the local pressure, and the electric field strength and other physical conditions for calculation, to judge whether the electron density formed by the current system has exceeded the pre-set ionization threshold. If the estimation result shows that the electron density is still insufficient, the system will continue to maintain the excitation state of the high-frequency electric field; if the density reaches or exceeds the threshold, it is considered that the plasma seeds have been successfully generated, and the ionization process can enter the maintenance or release stage, providing an electron field basis for the subsequent flame kernel expansion and self-sustaining control.

[0027] To ensure the high efficiency and high precision of this process, the influence of different gas types on the ionization process is fully considered in the system design. For example, hydrogen has significant differences from methane or propane in terms of ionization energy, so different ionization thresholds and electric field strength parameters need to be set. At the same time, since the gas flow velocity and mixing concentration in the torch cavity will interfere with the spatial stability of the ionization region, the system needs to monitor the mixed gas concentration fluctuation in real time, and adjust the excitation frequency and amplitude through dynamic electric field modulation technology to ensure that the plasma seeds can be generated at the right position and time and maintained for a sufficient length of time. In addition, to avoid overheating of the electrodes or energy waste caused by excessive ionization process, the high-frequency ionization module also has a built-in timing limiting mechanism. When the electron density is maintained at a high level for a long time and the fire kernel expansion is not triggered, the system will automatically reduce the excitation amplitude or turn off the electric field output to prevent device aging or thermal damage caused by the continuous operation of the high-frequency power supply.

[0028] The high-frequency ionization part also undertakes the collaborative task with the self-sustaining control part of the flame core. That is, when the system detects that the radius of the flame core has reached the condition for self-sustaining propagation, this module will automatically exit the working state to save energy consumption and reduce interference. If the flame core fails to form or becomes unstable after formation, the high-frequency ionization part can be restarted, and the electron density can be re-evaluated according to the temperature and pressure conditions again, and the ionization excitation process can be implemented. This re-entrant working mechanism endows the system with strong fault tolerance and robustness. Even under the influence of external gas flow disturbance, temperature fluctuation or gas concentration change, the dynamic adjustment ability of the electron density can be maintained through the feedback mechanism, ensuring that the system can continuously maintain the basic physical environment required for the ignition seeds.

[0029] The self-sustaining control part of the flame core undertakes the key judgment function of whether the flame is successfully established and can propagate stably. Its main role is to dynamically calculate the actual expansion of the flame core based on the changes in the internal temperature distribution, ionization state and flame core structure of the system, and judge whether the critical condition for sustainable combustion has been reached. Once it is confirmed that the flame core is formed and has the self-sustaining ability, the system will sequentially turn off the front-stage induction heating module and high-frequency ionization module to achieve the convergence control of the ignition process. On the contrary, if the expansion of the flame core is insufficient or the propagation fails, the system will restart the induction heating and ionization modules to continue to provide excitation energy to ensure the final ignition success. The core of the self-sustaining control part of the flame core is the real-time perception and analysis of the spatial size and structural evolution of the flame core. This process does not directly depend on the measurement results of a single sensor, but through constructing an evolution model of the flame core radius, combining the existing temperature, gas physical properties, thermal conductivity and reaction heat release characteristics in the system, and conducting comprehensive calculation and judgment.

[0030] In the specific implementation process, the system will first set multiple temperature sensors or flame detection elements based on the infrared detection principle near the ignition area. These detection devices do not directly measure the boundary of the flame core, but obtain the change of the thermal field distribution of the mixed gas at different positions. After the system collects the thermal field data, the effective radius of the current flame core area and the expansion speed of the flame front are indirectly estimated through the spatial calculation of the temperature gradient change. This calculation result will be compared with the set self-sustaining threshold. The self-sustaining threshold is usually preset according to factors such as gas type, flow rate, and ambient pressure, indicating the minimum spatial scale that the flame must reach under specific conditions to maintain a continuous combustion reaction chain. If the current radius of the flame core has exceeded the self-sustaining threshold, the system will judge that the flame has sufficient heat transfer ability and chemical reaction activity and can continue to propagate to the entire torch combustion area without relying on external energy input. At this time, the system will immediately turn off the induction heating module and ionization module, switch to the normal gas supply state, and maintain the torch in the self-sustaining combustion state to reduce power consumption and extend the service life of the device.

[0031] On the other hand, if the fire core significantly slows down its expansion speed after initial formation, or its spatial radius remains below the self-sustaining threshold for a long time, it indicates that the current ignition process fails to successfully trigger the self-sustaining combustion reaction. This situation may be caused by various reasons such as too fast gas flow rate, insufficient gas concentration, insufficient chip heating power, or low ionization electron density. At this time, the fire core self-sustaining control module will restart the induction heating module through logical judgment, and appropriately adjust the heating power, ionization duration, or mixed gas ratio according to the specific time point and parameter characteristics of the previous ignition failure to improve the success rate of the next ignition. This control module not only realizes the automatic determination of self-sustaining conditions and the closed-loop control of repeated attempts, but also constructs an adaptive flame stability optimization mechanism through the recording of system historical data and dynamic strategy adjustment. This feature is particularly important for coping with the torch ignition task in complex environments, especially in outdoor wind disturbances, gas concentration fluctuations, or frequent ignition start scenarios, which can effectively avoid the energy waste and equipment loss caused by repeated ignition failures.

[0032] Furthermore, the metal chip or metal catalyst body is located at the geometric center of the high-frequency coil, and the axial distance between the heating surface or the center point of the metal chip or metal catalyst body and the cross-sectional plane of the high-frequency coil is in the range of one-fourth to one-half of the radius of the high-frequency coil to maximize the magnetic flux coupling.

[0033] When the high-frequency coil is in the excited state, it will form an alternating magnetic field with relatively uniform distribution and the strongest magnetic flux density in its central region, and the thermal power of induction heating is proportional to the square of the magnetic flux density at this place. When the metal chip is located in this optimal axial magnetic flux density region, the induced current (i.e., eddy current) can form a high-intensity circular current path in its body, thus quickly generating the skin effect and triggering Joule heat. If the chip is too close to the coil plane, it may fall into the magnetic field interference blind area; if it is too far away, the magnetic flux density decays severely, resulting in a significant decrease in the induced power. Therefore, this technical structure accurately locks the strong coupling zone of the alternating magnetic field in the axial direction by restricting its arrangement distance between one-fourth and one-half of the radius. This can ensure concentrated, efficient, and uniform heating, thus providing a reliable and rapid thermal input basis for subsequent temperature rise discrimination, ionization induction, and fire core self-sustaining control in the torch ignition process.

[0034] Furthermore, the ignition area is a spherical area formed with a radius of 2 to 3 times the radius of the metal chip or metal catalyst body; the flow rate of the mixed gas is less than 0.5 m / s.

[0035] The ignition region is set as a spherical space range with a spherical radius of 2 to 3 times the radius of the metal chip or metal catalytic body, which is determined based on the typical spatial attenuation law of heat radiation and conduction in gas during the induction heating process. Under the action of a high-frequency alternating magnetic field, the metal chip will rapidly heat up, and the surface temperature can reach over 800 °C. This heat will diffuse to the surrounding gas in the form of radiation and conduction, and the actual heated region of the gas often exhibits an approximately spherical symmetric structure. Setting the ignition region to 2 to 3 times the chip radius is to ensure that the mixed gas within this region can reach or approach the self-ignition temperature of the fuel within a short time, meeting the spatial coverage requirements for triggering the temperature rise discrimination module. If this region is too small, it will lead to uneven heating and a decrease in the probability of forming a fire nucleus; if it is too large, the heat density will decrease, affecting the concentration of ignition energy. Therefore, choosing this proportional range is an optimal structural scale matching achieved among the heating power, gas heat capacity, and spatial response speed.

[0036] In addition, the flow rate of the mixed gas is restricted to less than 0.5 m / s because the gas flow rate has a direct impact on heat accumulation, energy loss, and the plasma maintenance time during the torch ignition process. Too fast a gas flow will quickly carry away the heat generated on the chip surface, causing a lag in gas temperature rise and unable to trigger the critical temperature discrimination in a timely manner; at the same time, it will also disperse the initially formed seed plasma clusters, making it difficult to maintain the free electron density above the threshold, directly resulting in ionization failure. Furthermore, if the flow rate is too high after the formation of the fire nucleus, it will also disrupt the propagation path of the flame front, preventing the flame from spreading stably. Therefore, by controlling the gas flow rate below 0.5 m / s, the heating efficiency of the chip heat on the local gas can be significantly improved, the residence time of the ionized particles can be extended, and it is ensured that the entire ignition chain can complete self-sustaining conversion within the physical time window.

[0037] Furthermore, at the moment the temperature of the mixed gas is as follows: ; where is the initial ambient temperature, with the unit of K; is the heat radiation and conduction efficiency, with a value range of 0.2 to 0.6; is the instantaneous power of induction heating, with the unit of W; is the effective area of direct contact between the metal chip or metal catalytic body and the mixed gas, with the unit of m²; is the density of the mixed gas, with the unit of kg / m³; is the specific heat capacity at constant pressure of the mixed gas, with the unit of J / (kg·K); is the volume of the ignition region; is the heat conduction time constant, which controls the temperature rise rate and has a value range of 5 ms to 100 ms.

[0038] Specifically, the first term on the right side of the formula reflects the thermal equilibrium background in the initial state of the gas, usually taking values from 293 K to 298 K under normal temperature conditions; the second term is the response term of the gas temperature over time, and its temperature rise amplitude is determined by the ratio between the heat transfer input intensity and the gas heat capacity impedance, while the exponential decay function term reflects the time characteristics of the heating process and characterizes the thermal inertia and conduction response speed of the system. Among them, is the effective thermal coupling efficiency between the metal chip or metal catalyst and the mixed gas, taking into account various influencing factors such as radiative heat transfer, contact heat conduction, and gas wrapping uniformity. In an actual system, its value usually ranges between 0.2 and 0.6. For example, when the chips are arranged compactly, the gas flow rate is low, and the thermal insulation is good, can take the upper limit value of 0.6; while if there is strong convection or the contact area between the chip and the gas is limited, then may drop to 0.2. The parameter is the instantaneous power generated by high-frequency induction heating, with the unit of watt, which is a direct indicator of the heating intensity. This power is generated by the high-frequency coil exciting eddy currents in the chip body through an alternating magnetic field, and the eddy currents flow in the metal body and generate Joule heat due to its own resistance characteristics. In an actual device, the induction power can be controlled by adjusting the frequency, current amplitude, or coil structure, and its typical value range is 50 to 200 watts. The parameter represents the actual heat exchange area between the chip and the gas, with the unit of square meter, and is usually determined according to the chip geometry. For example, if the chip is a disk with a diameter of 8 mm, its effective contact area is approximately 5.0×10^{-5} m².

[0039] Meanwhile, the density and the specific heat capacity at constant pressure of the gas determine the amount of thermal energy required per unit volume. Under normal temperature and pressure, the density of air or methane-air mixture is approximately 1.1 kg / m³, and the specific heat capacity is approximately 1000 J / (kg·K), which means that about 1.1 J of heat is required for every liter of gas to increase its temperature by 1 K. The parameter is the ignition region volume, which depends on the chip radius and the flame seed envelope range. If the chip radius is 4 mm and the ignition region takes a spherical structure with a radius 2.5 times that of the chip, then . Finally, is the heat conduction time constant, which is used to control the system response rate after heat input, and its typical value range is 5 ms to 100 ms. The specific value depends on the thermal diffusion characteristics of the gas and the surface thermal conductivity of the chip. A smaller means that the gas heats up faster, which is more conducive to rapid ignition.

[0040] Set the following parameters for a certain actual ignition process: initial temperature , thermal coupling efficiency , induction heating power , heat transfer area , gas density , specific heat capacity of gas , volume of the ignition area , thermal conduction time constant . Substitute the above parameters into the temperature rise formula, and the expression of temperature varying with time can be obtained: ; Calculate the ratio term among them. The thermal power term is 2.16 J / K, and the specific heat term is about 4.7 J / K. Then the temperature rise coefficient is about 460 K, which means that theoretically the gas can finally be heated by 460 K, that is, reach 758 K. Continue to calculate the time response: when , the exponential term is , and the corresponding temperature rise is about 290 K, and the gas temperature rises to 588 K; when , the exponential term is about 0.86, the temperature rise is 395 K, and the gas temperature is 693 K; if the heating continues until 0.1 s, the exponential term approaches 0.98, and the final temperature approaches the target value of 758 K. Thus, it can be seen that it only takes less than 0.1 second for the gas in the ignition area to rise from room temperature to above 700 K, basically approaching the lower limit of the auto-ignition temperature of gases such as methane, providing sufficient heat preparation for subsequent ionization excitation and flame kernel expansion.

[0041] Furthermore, the instantaneous power of induction heating is: ; Among them, is the conductivity of the metal chip or metal catalyst, with the unit of S / m; is the angular frequency of the alternating magnetic field, with the unit of rad / s; is the peak magnetic induction intensity of the high-frequency coil, with the unit of T; is the radius of the metal chip or metal catalyst, with the unit of m; is the eddy current penetration depth, with the unit of m; , among which, is the magnetic permeability of the material of the metal chip or metal catalyst, with the unit of H / m; is the conductivity of the metal chip or metal catalyst, with the unit of S / m.

[0042] In the intelligent torch ignition device based on high-frequency induction heating of the present invention, a reliable and controllable heat source must be established first to achieve a fast, stable and efficient ignition process. The heat source is generated by the metal chip or metal catalyst located in the center of the high-frequency coil being heated by high-frequency induction. Its essence is the Joule heating effect generated by the eddy current excitation of the metal material in the alternating magnetic field. Therefore, the instantaneous thermal power model of induction heating is the primary basis for modeling the ignition process, and its expression is: .in, Indicates the electrical conductivity of a metal chip or metal catalyst, in units of S / m, and describes the ability of a metal material to conduct current. The higher the electrical conductivity, the greater the Joule heat generated by a unit current per unit volume, and therefore has a direct impact on the efficiency of eddy current heating. Common materials such as copper, nickel, molybdenum, etc., usually have a conductivity range of to S / m, when selecting materials, both conductivity and high temperature stability must be considered. It represents the angular frequency of the alternating magnetic field of the excitation coil in rad / s and is defined as ,in is the excitation frequency, in Hz. In this system, the operating frequency of the high-frequency power supply is generally set to tens to hundreds of kilohertz, corresponding to exist to In the rad / s range, the higher the angular frequency, the more dramatic the magnetic field change, the greater the induced electromotive force, and the stronger the eddy current. It is the peak magnetic induction intensity of the alternating magnetic field generated in the coil, measured in Tesla (T), usually ranging from 0.01 to 0.1 T, and is determined by the excitation current, the number of coil turns, and the geometric configuration. The magnetic field strength directly determines the size of the magnetic flux passing through the unit area, thereby controlling the induced potential amplitude and the excitation current intensity.

[0043] The chip's geometric parameters also have an important influence on the induction power. The radius of the metal chip or catalyst is in meters, and its square is proportional to the induction power. A larger chip provides a wider induction path and a larger heating volume, but it also brings greater thermal inertia and higher energy consumption. Therefore, the thermal power required for ignition and the volume limit should be considered in the design. The last key parameter is the eddy current penetration depth in meters and is defined as: This item describes the penetration distance of the alternating magnetic field that can effectively induce eddy currents in a conductor, which is a quantitative parameter of the skin effect. The higher the magnetic field frequency, the greater the conductivity, or the stronger the magnetic permeability, the shallower the penetration depth, that is, the eddy currents are mainly concentrated near the metal surface, generating surface-concentrated Joule heat. This characteristic enables the chip to achieve a high surface temperature in an extremely short time, thereby quickly transferring the heat to the surrounding combustible gas in the form of radiation and heat conduction to achieve the temperature rise preparation before ignition. The penetration depth not only controls the spatial distribution of the eddy currents but also affects the equivalent heating volume and the actual power density, which is an important basis for designing the chip thickness and material selection.

[0044] Suppose the selected material is electrolytic copper, and its conductivity is S / m, and the magnetic permeability is taken as H / m (the magnetic permeability of non-ferromagnetic materials is approximately the magnetic permeability of vacuum), the high-frequency excitation frequency is 100 kHz, and the corresponding angular frequency is rad / s. Substituting the above values into the eddy current penetration depth formula, we get: ; This indicates that under this excitation condition, the induction heating is mainly concentrated in the area of 66 microns on the chip surface. If the radius of the chip is m (i.e., the diameter is 8 mm), and the peak value of the magnetic induction intensity is T, then the instantaneous induction power is: ; For the calculation, first calculate each term: ; ; ; Substituting, we get: ; ; The result shows that the induction power is about 62 watts, which can raise the chip surface temperature to over 600 °C in an extremely short time and quickly form a thermal excitation zone for the surrounding gas to achieve the critical heat input required for ignition. Since the heated area on the chip surface is thin and concentrated, the thermal inertia is low, and the response speed is fast, which is very suitable for application scenarios such as high-frequency startup and high-speed ignition.

[0045] Furthermore, the heat conduction time constant is: ; Among them, is the heat transfer coefficient between the metal chip or metal catalyst and the gas, and its value range is 50 to 200, with the unit of W / (m²·K).

[0046] Among them, is the density of the mixed gas, with the unit of , which determines the mass contained in a unit volume of gas; is the specific heat capacity at constant pressure of the gas, with the unit of , reflecting the energy required to raise the temperature of a unit mass of gas by 1K; the product of the two is the heat required to raise the temperature of a unit volume of gas, which is further multiplied by the volume of the ignition region, representing the total heat capacity of the mixed gas in the entire ignition space. The denominator term represents the heat power released by the metal chip to the gas under a unit temperature difference, where is the heat transfer coefficient, with the unit of , which is an empirical constant describing the comprehensive heat transfer processes such as heat conduction and convection, reflecting the heat transfer rate under a unit area and a unit temperature difference; is the effective heat transfer area between the chip and the gas, with the unit of . Therefore, the entire expression embodies the basic characteristics of "total heat capacity / heat power". The larger its value, the slower the heat conduction reaction; the smaller, the faster the heat response and the more rapid the gas heating process. From the perspective of engineering implementation, control is crucial for the stability and sensitivity of the entire ignition device. If is too large, although the induction heating is strong, the heat diffusion efficiency in the gas is low, and it is difficult to quickly form a critical temperature zone for ignition, resulting in ignition failure or increased energy consumption; if is too small, although it is beneficial for rapid heating, it may cause local overheating or flame instability, affecting the system reliability. Therefore, in the design, it is necessary to control to fall within the ideal range of 5ms to 100ms by reasonably matching the gas type, chip geometric parameters, material selection, and environmental flow field.

[0047] Let the volume of the ignition region be, the mixed gas is methane–air, with a density under normal pressure and room temperature, and a specific heat capacity at constant pressure . The effective heat transfer area of the metal chip is . Suppose in the design of the control system, the heat transfer coefficient is taken, then it can be calculated that: ; This value is obviously too large, indicating that if only relying on the above parameter combination, the gas temperature rise rate is slow and cannot meet the requirements of rapid ignition. At this time, the system design should increase or increase , for example, select a material with better thermal conductivity (such as a nickel-based catalyst body) or optimize the chip surface structure to enhance the turbulent heat transfer effect. When is increased to 200W / (m²·K), can be reduced to about 0.52 seconds. If is further reduced to , then you can The system response speed can be significantly improved by controlling the time to less than 0.3 seconds. In addition, if the induction power is increased and dynamic feedback is adjusted, the overall ignition time of the system can be shortened to between 0.1 and 0.2 seconds, which fully meets the dual requirements of industrial-grade torch systems for response time and reliability.

[0048] The numerical adjustment of is also closely related to the judgment time window of fire core formation. In the ionization and flame core propagation module, if the gas temperature rises too slowly and fails to reach the auto-ignition temperature in time, the seed ionization will dissipate quickly, causing ignition failure. Therefore, a real-time estimation model can be set in the control logic to calculate the induction power , heat capacity and heat transfer coefficient Substitute together to estimate , dynamically predict the evolution of gas temperature and determine in advance whether ionization excitation can be triggered. At the same time, the model can also be used as an indirect indicator for monitoring chip material aging and airflow interference status. If it is significantly larger, it may indicate that there is a problem in the heat exchange path and maintenance or parameter readjustment is required.

[0049] Furthermore, at the moment The electron density in the mixed gas is for: ; in, is the vacuum dielectric constant, which is 8.854×10 -12 , unit is F / m; is the electric field strength of the high-frequency coil, in V / m; is the density of neutral gas molecules, in m -3 ; is the average collision frequency; is the electron mobility, in m² / (V·s); is Planck's constant; is the equivalent plasma frequency induced by the high-frequency coil, in Hz; is the nonlinear ionization damping coefficient of the gas medium, in Pa -1 ; is the static pressure of the mixed gas; The ionization cross section is measured in m², which indicates the probability of a unit electron ionizing a neutral particle per unit time.

[0050] When the mixed gas is excited by a high-frequency electric field, valence electrons in some neutral molecules or atoms gain external energy and escape from the atomic orbit to form free electrons; these free electrons are further accelerated in the electric field and induce more electrons to escape through collisions with other neutral molecules, thus forming a cascade ionization process of electrons. In the system, the rate of change of electron density is limited by physical properties such as the molecular density of the gas, the collision frequency, and the migration ability of free electrons, and is also inhibited by the nonlinear dissipation effect brought about by the gas pressure itself. Therefore, this expression not only describes the ionization growth behavior of the gas under the action of a high-frequency electric field, but also introduces gas pressure and nonlinear losses into the model to achieve dynamic determination of ignition effectiveness under different working conditions.

[0051] Furthermore, at the moment the radius of the ignition kernel is: ; where, is the initial ignition kernel radius, with a value range of 1 to 3, and the unit is mm; is the flame propagation enhancement coefficient, which represents the increase in the ignition kernel expansion rate caused by eddy current or thermal diffusion; is the thermal conductivity of the mixed gas, with the unit of W / (m·K); is the autoignition temperature of the mixed gas; is the heat release of combustion per unit mass of the mixed gas.

[0052] The flame speed is jointly determined by the thermal diffusion term and the combustion reaction excitation term. Under isobaric conditions, the propagation speed of the combustion wave can be simplified as follows: ; This expression is derived from the thermal flame theory and considers that the speed of the flame propagation front is related to the thermal conductivity of the medium, the difference between the temperature and the ignition temperature, and the ratio of the gas heat capacity to the heat of combustion. is the thermal conductivity of the mixed gas, which determines the ability of thermal diffusion propagation; characterizes the temperature gradient between the ignition kernel region and the autoignition limit, and is the thermal driving force for flame propagation; is the gas density, is the heat release of combustion per unit mass of the gas, and their ratio is a measure of the heat energy that can be released per unit volume, which determines whether thermal propagation can be maintained at a certain temperature rise. Since the flame propagation in this system is not a pure thermal diffusion process and is enhanced by multiple factors such as residual induction excitation, ionization channel guidance, and gas flow field disturbance, a correction factor , known as the flame propagation enhancement coefficient. This coefficient is usually greater than 1, and its value is obtained based on experimental calibration or simulation parameters, representing the flame speed gain caused by mechanisms such as turbulence, plasma excitation, and gas self-convection. Under ideal static conditions, ; in an environment with enhanced combustion, can reach 1.5 - 3.0. Therefore, the fire kernel propagation speed is expressed as: ; Integrating this expression over the time dimension yields the complete formula for the variation of the above-mentioned fire kernel radius with time: ; In this expression, the temperature function is the real-time gas temperature distribution function estimated through the induction heating model in the previous stage and has the following form: ; Substituting this temperature function into the fire kernel propagation expression can further directly couple the fire kernel expansion with the input of the previous-stage heat source, enabling the system to have the continuous modeling ability of the whole process of temperature rise - ionization - diffusion - self-sustaining.

[0053] For example, assume that after the chip is inductively heated, the gas temperature rises to , the auto-ignition temperature of the mixed gas is , the gas thermal conductivity is , the density is , the heat release per unit mass of combustion is , take the enhancement coefficient , the initial fire kernel radius , then the propagation speed is: ; If the system enters the ionization expansion stage and lasts for 0.1 seconds after inductive heating, the fire kernel expansion length is approximately , and the total fire kernel radius is . If the temperature is further increased to , then the propagation speed increases rapidly and can reach , meaning that the fire kernel will expand to the range of 3 - 5 mm within a few hundred milliseconds, sufficient to enter the self-sustaining stage. The radius growth in this process directly determines whether to trigger the system to judge the "fire kernel self-sustaining success" logic, which is the key condition input for the "self-judgment - self-control - self-retreat" in the present invention.

[0054] Further, the critical temperature is the auto-ignition temperature of the mixed gas; assume the ionization threshold is ; when and , execute electric field excitation; when the mixed gas is a mixture of methane and air, The value range of ; when the mixed gas is a mixture of propane and air, The value range of ; when the mixed gas is a mixture of oxygen and hydrogen, The value range of .

[0055] Taking the methane-air mixed gas as an example, the autoignition temperature of methane is about , in the ignition control logic, when the temperature function of the gas after induction heating reaches this temperature and the electron density function exceeds , the system starts the electric field excitation. Let the peak electric field intensity of the high-frequency coil at this time be , the gas density be , the electron mobility be , the plasma frequency be , the Planck constant and the vacuum permittivity are taken as and , and through calculation, the electron density at this moment is about , meeting the excitation conditions. The system immediately drives the release of the high-frequency electric field, further enhancing the ionization cascade reaction rate, enabling the free electrons generated by primary ionization to produce secondary ionization through collisions, thus quickly forming a high-density plasma channel. In contrast, if the mixed gas is propane–air, its autoignition temperature is , but the required electron density is higher, about , because the propane molecular structure is more complex, the ionization energy is higher, and it has a greater dependence on high-energy electrons. Therefore, the system requires a stronger induction power or a longer preheating time under the same heating conditions to ensure that the ionization criterion is established. If a hydrogen–oxygen mixed gas is used, due to the low ionization energy of hydrogen, the autoignition temperature is , and the electron threshold density only needs to reach , and the system can complete the temperature rise and ionization preheating in a very short time, with the overall response time controlled within 0.05 seconds, suitable for a high-speed start-up torch system.

[0056] Chip material: copper (conductivity S / m, magnetic permeability H / m); chip radius: m; high-frequency coil operating frequency: kHz, rad / s; peak magnetic induction intensity: T; induction effective area: m²; heat radiation and heat conduction efficiency: ; ignition sphere radius: m, volume m³; Density of the mixed gas: kg / m³; Specific heat capacity at constant pressure: J / (kg·K); Thermal conductivity: W / (m·K); Heat release during combustion: J / kg; Auto-ignition temperature: K; Initial temperature: K; Ionization threshold: m -3 ; Electric field strength: V / m; Gas molecular density: m -3 ; Collision frequency: Hz; Electron mobility: m² / (V·s); Plasma frequency: Hz; Ionization cross-section: m²; Nonlinear damping factor: Pa -1 ; Gas static pressure: Pa; , .

[0057] ; Inductive power: ; ; Gas temperature evolution (taking ): ; At this time, the temperature has not reached the critical value, and the heating time needs to be extended.

[0058] If , the following can be obtained: ; Continue to extend to , and the following can be reached: ; It is still lower than the auto-ignition temperature. Therefore, by increasing to 0.07T: ; Recalculate the new temperature, , which already meets ;

[0059] Meet , and electric field excitation can be performed.

[0060] Let , mm, substitute into: ; If it continues until , mm, it meets the self-sustaining propagation threshold.

[0061] Calculations through this example show that after using a copper chip, a methane–air mixture, and boosting the high-frequency power to 120 W for 2.5 seconds of excitation time, both the gas temperature and electron density reach the conditions for triggering ignition. After 0.5 seconds of continuous electric field excitation, the fire kernel radius expands to 3.0 mm, meeting the self-sustaining combustion criterion, thus realizing a complete intelligent torch ignition process.

[0062] Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that these specific embodiments are merely illustrative. Without departing from the principles and essence of the present invention, those skilled in the art can make various omissions, substitutions, and changes to the details of the above methods and systems. For example, combining the above method steps so as to perform substantially the same function in a substantially the same way to achieve substantially the same result falls within the scope of the present invention. Therefore, the scope of the present invention is only defined by the appended claims.

Claims

1. An intelligent torch ignition device based on high-frequency induction heating, characterized in that, The device includes: an eddy current heating part for arranging a high-frequency coil in the ignition area, generating an alternating magnetic field through the high-frequency coil, inducing eddy currents in the metal chip or metal catalytic body inside the torch, and performing induction heating to form a high-density heat source; a critical temperature rise discrimination part for discriminating whether the temperature of the mixed gas exceeds the critical temperature when the mixed gas is heated by the radiation and heat conduction of the metal chip or metal catalytic body; a high-frequency ionization part for estimating the electron density in the mixed gas when the temperature of the mixed gas exceeds the critical temperature, comparing the electron density with the ionization threshold, and if the electron density exceeds the ionization threshold, performing electric field excitation to maximize the plasma formation efficiency; and a self-sustaining control part for the fire core, which constructs a fire core radius expansion function, calculates the fire core radius in real time, and if the fire core radius reaches the self-sustaining threshold, determines that the fire core can reach self-sustaining, and then stops the induction heating and electric field excitation in sequence. If the fire core radius does not reach the self-sustaining threshold, continue with the induction heating and electric field excitation.

2. The intelligent torch ignition device based on high-frequency induction heating according to claim 1, wherein, The metal chip or metal catalytic body is located at the geometric center of the high-frequency coil, and the axial distance between the heating surface or the center point of the metal chip or metal catalytic body and the cross-sectional plane of the high-frequency coil is in the range of one-fourth to one-half of the radius of the high-frequency coil to maximize the magnetic flux coupling.

3. The intelligent torch ignition device based on high-frequency induction heating according to claim 2, characterized in that, The ignition area is a spherical area formed with a radius of 2 to 3 times the radius of the metal chip or metal catalytic body; the flow rate of the mixed gas is less than 0.5 m / s.

4. The intelligent torch ignition device based on high-frequency induction heating according to claim 3, wherein, At the moment the temperature of the mixed gas is which is ； Among them, is the initial ambient temperature, with the unit of K; is the heat radiation and conduction efficiency, and its value range is from 0.2 to 0.6; is the instantaneous power of induction heating, with the unit of W; is the effective area of direct contact between the metal chip or metal catalyst and the mixed gas, with the unit of m²; is the density of the mixed gas, with the unit of kg / m³; is the specific heat capacity at constant pressure of the mixed gas, with the unit of J / (kg·K); is the ignition area volume; is the heat conduction time constant, which controls the temperature rise rate, and its value range is from 5 ms to 100 ms.

5. The intelligent torch ignition device based on high-frequency induction heating according to claim 4, characterized in that, Instantaneous power of induction heating is as follows: ； Among them, is the conductivity of the metal chip or metal catalyst, with the unit of S / m; is the angular frequency of the alternating magnetic field, with the unit of rad / s; is the peak magnetic induction intensity of the high-frequency coil, with the unit of T; is the radius of the metal chip or metal catalyst, with the unit of m; is the eddy current penetration depth, with the unit of m; , where is the magnetic permeability of the material of the metal chip or metal catalyst, with the unit of H / m; is the conductivity of the metal chip or metal catalyst, with the unit of S / m.

6. The intelligent torch ignition device based on high-frequency induction heating according to claim 5, characterized in that, Thermal conduction time constant is as follows: ； Among them, is the heat transfer coefficient between the metal chip or metal catalyst and the gas, with a value range of 50 to 200 and the unit of W / (m²·K).

7. The intelligent torch ignition device based on high-frequency induction heating according to claim 6, characterized in that, At the moment the electron density in the mixed gas is: ； Among them, is the vacuum permittivity, with a value of 8.854×10 -12 , and the unit is F / m; is the electric field strength of the high-frequency coil, and the unit is V / m; is the density of neutral gas molecules, and the unit is m -3 ; is the average collision frequency; is the electron mobility, and the unit is m² / (V·s); is the Planck constant; is the equivalent plasma frequency induced by the high-frequency coil, and the unit is Hz; is the non-linear ionization damping coefficient of the gas medium, and the unit is Pa -1 ; is the static pressure of the mixed gas; is the ionization cross-section, and the unit is m², indicating the probability that a single electron ionizes neutral particles per unit time.

8. The intelligent torch ignition device based on high-frequency induction heating according to claim 7, characterized in that, At the moment the radius of the nuclear fireball is: ； Among them, is the initial fire kernel radius, with a value range of 1 to 3, and the unit is mm; is the flame propagation enhancement coefficient, indicating the increase in the fire kernel expansion rate caused by eddy current or thermal diffusion; is the thermal conductivity of the mixed gas, with the unit of W / (m·K); is the self-ignition temperature of the mixed gas; is the heat release of combustion per unit mass of the mixed gas.

9. The intelligent torch ignition device based on high-frequency induction heating according to claim 8, wherein The critical temperature is the autoignition temperature of the gas mixture ; Let the ionization threshold be ; When and , electric field excitation is performed; When the gas mixture is a mixture of methane and air, The value range of is ; When the gas mixture is a mixture of propane and air, The value range of is ; When the gas mixture is a mixture of oxygen and hydrogen, The value range of is .

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