High-speed weapon wireless ignition system based on electromagnetic induction coupling

Abstract

The application relates to a high-speed weapon wireless ignition system based on electromagnetic induction coupling, and belongs to the technical field of high-speed weapon ignition launching and wireless power transmission. The application is mainly aimed at the series launching technology of high-speed weapons, is designed according to the characteristic requirements and structure limitations of high-speed weapons, and makes up for the shortcomings of the conventional electric ignition technology, such as easy pollution of contacts, poor contact and the like, overcomes the problem that the energy transmission loss is too large in a metal environment, significantly improves the wireless energy transmission efficiency, and improves the reliability of the ignition system and the combat effectiveness of the high-speed weapon.

Description

Technical Field

[0001] This invention relates to a wireless ignition system for high-rate-of-fire weapons based on electromagnetic induction coupling, belonging to the field of high-rate-of-fire weapon ignition and launch and wireless power transmission technology. Background Technology

[0002] With the continuous upgrading and iteration of weapon technologies in various countries, missile flight speeds are constantly increasing, and the swarm and collaborative technologies of unmanned aerial vehicles (UAVs) are becoming increasingly mature, posing a significant challenge to the close-range defense of important targets. Current theoretical analysis suggests that to intercept missiles with speeds exceeding Mach 2.5, high-rate-of-fire weapons should achieve a rate of fire of 8,000 to 10,000 rounds per minute. For intercepting even faster-flying weapons, even higher requirements are placed on the rate of fire and the density of the barrage. In 1996, Mike O'Dwyer of Australia proposed a new firing method called "Metal Storm," which employs a tandem propellant structure and electronic ignition, significantly increasing the weapon's rate of fire. The core of this technology is the pre-loading of multiple projectiles end-to-end within a single barrel, sequentially fired using an electronic firing device, typically in multi-barrel configurations. Because Metal Storm eliminates the need for a series of mechanical actions such as unlocking, recoil, ejection, return, loading, locking, and firing during launch, it greatly shortens the firing time, enabling ultra-high-frequency firing. High-rate-of-fire cannons using this technology are well-suited as close-range air defense weapons to protect important facilities such as airports and large ships. They can effectively strike targets such as highly mobile weapons, drone swarms, and armored formations, and are of great significance for close-range air defense, strikes against swarm targets, and area blockade.

[0003] The key technology for high-rate-of-fire weapons is high-rate-of-fire tandem firing technology. This technology still faces many challenges, one of which is electric ignition technology. Conventional electric ignition technology uses wires to connect to an external power source or an internal charging capacitor for power. Both methods require direct contact between the wires and the projectile, necessitating modifications to the barrel structure. Furthermore, the ignition contacts are easily contaminated, reducing ignition reliability. Additionally, the complex metallic environment inside high-rate-of-fire weapons leads to severe losses and interference during wireless energy transmission, resulting in extremely low transmission efficiency and failing to meet the inductive ignition requirements of high-rate-of-fire weapons. Summary of the Invention

[0004] In view of this, the present invention provides a high-rate-of-fire weapon wireless ignition system based on electromagnetic induction coupling. The energy transfer between the primary and secondary coils is achieved through magnetic field induction coupling between the coils. The receiving coil is connected to the topology circuit, which then transfers the energy to the pyrotechnic device. Finally, the pyrotechnic device ignites the propellant to achieve energy transfer and complete the entire ignition process.

[0005] The technical solution of this invention is: The high-rate-of-fire weapon wireless ignition system based on electromagnetic induction coupling has a cylindrical structure, consisting of a receiving coil frame 4, a receiving coil 6, an inner tube 8, an outer shielding layer 9, and an outer tube 10 from the inside out. The transmitting coil 7 is embedded inside the inner tube 8.

[0006] The high-rate-of-fire weapon employs a customized ammunition tandem stacking structure design. This ammunition relies on a sabot for positioning and utilizes a recoil ring to seal the propellant gases, ensuring successful firing. During actual loading, a certain preload is applied to the recoil ring, ensuring its inner surface is tightly pressed against the sabot surface. Its working principle is to maintain the projectile's position and overall airtightness through self-locking during firing. The power input circuit at the high-rate-of-fire weapon's firing end uses a full-bridge inverter circuit, employing pulse width modulation to adjust the inverter's output equivalent voltage, with MOSFETs as switching transistors. The rectifier circuit at the high-rate-of-fire weapon's receiving end uses Schottky diodes as switching transistors. Based on the above design, field-circuit coupling circuit simulations are performed to verify the system's effectiveness. In the wireless ignition system, the receiving coil 6 transmits energy to the pyrotechnics of the high-rate-of-fire weapon through a topology circuit, igniting the pyrotechnics and propelling the projectile. The receiving coil 6 is connected to the topology circuit, which then transmits energy to the new pyrotechnics. Finally, the new pyrotechnics ignite the propellant to achieve energy transfer and complete the entire ignition process. The inner tube 8 is made of alumina ceramic; The outer tube 10 is made of titanium alloy; the primary transmitting coil 7 is directly embedded in the alumina ceramic, and the outer side of the ceramic is pre-tightened with a titanium alloy tube to enhance the reliability of the tube. The outer shielding layer 9 is made of a thin layer of aluminum metal; The receiving coil frame 4 is made of ferrite and can also serve as an inner shielding layer. The aforementioned circuit uses the SS topology as a resonant compensation circuit. The transmission efficiency model of the wireless ignition system is as follows:

[0007] The receiver load voltage gain model of the wireless ignition system is as follows:

[0008] in, X 2 represents the reactance of the receiving coil. k The coupling coefficient; Since the load is purely resistive, the voltage gain is positively correlated with the load power, and the voltage gain is used to characterize the power change. The receiving coil 6 is a single-layer coil with a pitch of [missing information]. coil radius Number of coil turns The coil material is copper Litz wire; The transmitting coil 7 is a single-layer coil with a pitch of [missing information]. coil radius Number of coil turns The coil material is copper Litz wire; The distance between the receiving coil 6 and the transmitting coil 7 .

[0009] Beneficial effects (1) The tandem stacked structure design in this invention can achieve effective positioning of the ammunition and sealing of the propellant gas to ensure firing. The radially inward force generated by the anti-recoil ring will also prevent the sabot from being displaced from the core.

[0010] (2) The ignition system structure design in this invention places the coil and topology circuit at the rear of the projectile, avoiding the influence of a large amount of metal at the front of the projectile and the slight deformation that the front is prone to due to the pressure of the propellant gas from the previous projectile.

[0011] (3) This invention uses a combination of high-strength alumina ceramic and titanium alloy as the tube material. The primary transmitting coil is directly embedded in the alumina ceramic, and the outer side of the ceramic is pre-tightened with a titanium alloy tube to enhance the tube reliability, which enables effective energy transfer between the coils. This overcomes the problem that regardless of whether the material has high permeability, low conductivity, or simply high conductivity, a certain thickness will affect the energy transfer between the coils on both sides, resulting in extremely low energy transfer efficiency.

[0012] (4) In this invention, ferrite is used as the receiving coil skeleton material and the inner shielding material, and aluminum is used as the outer shielding material. This scheme can effectively confine the magnetic field between the inner and outer materials, achieving a good shielding effect. Furthermore, the outer shielding uses a thin metal layer to avoid affecting the overall strength.

[0013] (5) This invention selects the SS topology as the resonant compensation circuit. This topology is not sensitive to parasitic parameters in the circuit, and the component parameters are easy to calculate, making it suitable for the ignition system of small-caliber, high-rate-of-fire weapons. After verification by the field-circuit coupling circuit, the induction ignition time of the system meets the requirements.

[0014] (6) The theoretical transmission efficiency of the coil structure parameters designed for the example in this invention. Voltage gain It can well meet the application requirements.

[0015] (7) A high-rate-of-fire weapon based on electromagnetic induction coupling according to the present invention includes a series stacked structure design, an ignition system structure design, a barrel material and magnetic shielding design, a coil design, and a field-circuit coupling simulation circuit design. The present invention is mainly aimed at the series launch technology of high-rate-of-fire weapons. It is specifically designed according to the characteristic requirements and structural limitations of high-rate-of-fire weapons, making up for the shortcomings of conventional electric ignition technology such as easy contamination of contacts and poor contact, overcoming the problem of excessive energy transmission loss in the metal environment, significantly improving the wireless energy transmission efficiency, improving the reliability of the ignition system and the combat effectiveness of high-rate-of-fire weapons. Attached Figure Description

[0016] Figure 1 The three-dimensional structure of the wireless ignition system; Among them, 4-receiving coil frame, 6-receiving coil, 7-transmitting coil, 8-inner tube, 9-outer shielding layer, 10-outer tube; Figure 2 This is a cross-sectional view of a wireless ignition system. Figure 3 It is an SS topology circuit; Figure 4 This is a schematic diagram of the parameters that affect the characteristics of the coil. Detailed Implementation

[0017] The high-rate-of-fire weapon wireless ignition system proposed in this invention will now be described in detail with reference to the accompanying drawings. The high-rate-of-fire weapon wireless ignition system based on electromagnetic induction coupling has a cylindrical structure, consisting of, from the inside out, a receiving coil frame 4, a receiving coil 6, an inner tube 8, an outer shielding layer 9, and an outer tube 10. The transmitting coil 7 is embedded inside the inner tube 8.

[0018] The high-rate-of-fire weapon employs a customized ammunition tandem stacking structure design. This ammunition relies on a sabot for positioning and utilizes a recoil ring to seal the propellant gases, ensuring successful firing. During actual loading, a certain preload is applied to the recoil ring, ensuring its inner surface is tightly pressed against the sabot surface. Its working principle is to maintain the projectile's position and overall airtightness through self-locking during firing. The power input circuit at the high-rate-of-fire weapon's firing end uses a full-bridge inverter circuit, employing pulse width modulation to adjust the inverter's output equivalent voltage, with MOSFETs as switching transistors. The rectifier circuit at the high-rate-of-fire weapon's receiving end uses Schottky diodes as switching transistors. Based on the above design, field-circuit coupling circuit simulations are performed to verify the system's effectiveness. In the wireless ignition system, the receiving coil 6 transmits energy to the pyrotechnics of the high-rate-of-fire weapon through a topology circuit, igniting the pyrotechnics and propelling the projectile. The receiving coil 6 is connected to the topology circuit, which then transmits energy to the new pyrotechnics. Finally, the new pyrotechnics ignite the propellant to achieve energy transfer and complete the entire ignition process. The inner tube 8 is made of alumina ceramic; The outer tube 10 is made of titanium alloy; the primary transmitting coil 7 is directly embedded in the alumina ceramic, and the outer side of the ceramic is pre-tightened with a titanium alloy tube to enhance the reliability of the tube. The outer shielding layer 9 is made of a thin layer of aluminum metal; The receiving coil frame 4 is made of ferrite and can also serve as an inner shielding layer. The aforementioned circuit uses the SS topology as a resonant compensation circuit. The transmission efficiency model of the wireless ignition system is as follows:

[0019] The receiver load voltage gain model of the wireless ignition system is as follows:

[0020] in, X 2 represents the reactance of the receiving coil. k The coupling coefficient; Since the load is purely resistive, the voltage gain is positively correlated with the load power, and the voltage gain is used to characterize the power change. The receiving coil 6 is a single-layer coil with a pitch of [missing information]. coil radius Number of coil turns The coil material is copper Litz wire; The transmitting coil 7 is a single-layer coil with a pitch of [missing information]. coil radius Number of coil turns The coil material is copper Litz wire; The distance between the receiving coil 6 and the transmitting coil 7 .

[0021] (1) The high-rate-of-fire weapon designed in this invention is difficult to position when stacked in series due to the different diameters of the standard ammunition casing and sabot, the front part of the casing, and the rear part of the casing. It is also impossible to extract and eject the casing during continuous firing. Therefore, this invention uses customized ammunition. This type of ammunition relies on the sabot for positioning and uses a recoil ring to seal the propellant gas to ensure firing. In actual loading, a certain preload is applied to the recoil ring to make its inner surface tightly adhere to the sabot surface. Its working principle is to ensure the position of the projectile and the overall airtightness through self-locking during firing. The main working process is as follows: when the previous projectile is fired, its propellant gas pressure acts on the sabot and the core, and the projectile as a whole retreats slightly. The contact surfaces of the tightly fitted sabot and the recoil ring will generate equal and opposite normal pressure and friction. At this time, the recoil ring will expand slightly due to the force, so that the contact surface between the recoil ring and the barrel will also generate equal and opposite normal pressure and friction to prevent it from retreating. The radially inward force generated by the anti-recoil ring also prevents the sabot from shifting away from the projectile core.

[0022] (2) Based on the completed design of the series stacked structure, the structure of the ignition system is designed to minimize interference with the surrounding environment while achieving energy transfer. Since the front of the projectile contains a significant amount of metal, and to withstand the rearward pressure of the propellant gas from the previous projectile, the front is prone to slight deformation. Therefore, this invention places the coil and topology circuit at the rear of the projectile. The receiving coil is connected to the topology circuit, which then transfers energy to the new pyrotechnic device. Finally, the new pyrotechnic device ignites the propellant to achieve energy transfer, completing the entire ignition process.

[0023] (3) Due to the presence of a metallic environment around the transmitting and receiving coils, the magnetic field strength and distribution between the coils are affected, which in turn affects the coil circuit parameters and the system energy transfer characteristics. Therefore, based on the above-mentioned series stacked structure design and ignition system structure design, the materials of each part are optimized to minimize the impact and increase energy transfer efficiency. The three-dimensional structure and cross-sectional view of the wireless ignition system are shown below. Figure 1 and Figure 2 As shown, based on the application characteristics requirements, this invention proposes a solution that combines high-strength alumina ceramic with titanium alloy. In this solution, the primary transmitting coil is directly embedded in the alumina ceramic, and the outer side of the ceramic is pre-tightened with a titanium alloy tube to enhance the reliability of the tube.

[0024] (4) Based on the determined tube material, in order to enhance the internal magnetic field and avoid additional interference and temperature rise in other circuits and metals, a magnetic shielding mechanism is designed from two aspects: effectively confining the magnetic field internally and completely shielding the magnetic field externally. The outer shielding uses a thin metal layer to avoid affecting the overall strength. Through simulation verification, this invention selects ferrite as the receiving coil skeleton material and inner shielding material, and aluminum as the outer shielding material. This scheme can effectively confine the magnetic field between the inner and outer materials, achieving a good shielding effect.

[0025] (5) Regarding the selection of the topology, since the SS topology is not sensitive to parasitic parameters in the circuit, the component parameters are easy to calculate. For the ignition system of small-caliber high-rate-of-fire weapons, the size requirements of its receiver are relatively strict, and the number of components should be minimized and smaller packages should be selected. Therefore, the SS topology is selected as the resonance compensation circuit. The SS topology circuit is as follows: Figure 3 As shown. and These are the transmitting and receiving coils, respectively. and These are the resonant compensation capacitors for the transmitting and receiving ends, respectively. and Parasites on the transmitting and receiving coils, respectively. and These are the loop currents of the transmitting and receiving coils, respectively. For power supply, For load resistance, This refers to the mutual inductance between the transmitting and receiving coils.

[0026] To model it using mutual inductance theory, we first establish the KVL equations for the transmitter and receiver. (3) (4) In the formula, ( ) is the reactance of the resonant circuit.

[0027] The current in the receiving coil circuit is (5) Substituting the above equation into equation (3), we can obtain the system's input impedance as follows: (6) In the formula, the reflection impedance is This refers to the additional equivalent impedance generated by the current in the receiving coil.

[0028] Assuming the primary and secondary resonators have the same resonant frequency, and this frequency is equal to the system's operating frequency, then the reactance... and It equals zero. At this point, the induced voltage and current in the receiving coil circuit can be derived as follows: (7) (8) The gain of the receiving coil circuit is (9) If the parasitic resistance of the receiving coil circuit is ignored , then (10) Because this ignition system is near-field coupled, radiation losses are negligible, and all losses in the resonant circuit will depend on parasitic resistance, i.e. and Therefore, the efficiency of the system can be expressed as (11) In the formula, The system efficiency is determined solely by equation (4), therefore it is not affected by equation (3). That is, it is unaffected by the reactance value of the transmitting coil circuit. The effect of the replacement is that the efficiency expression is: (12) The receiver load voltage gain is (13) Since the load is purely resistive, the voltage gain is positively correlated with the load power. Therefore, to simplify the analysis, the voltage gain can be used to characterize the power change.

[0029] (6) As the main energy transfer component, the coil's structural parameters determine not only its circuit parameters but also its magnetic field distribution. Therefore, its structural parameters need to be designed. Parameters affecting the coil's characteristics include... Figure 4 As shown. Geometric parameters in coil design include: coil pitch. , radius of the conductor Number of turns of the transmitting coil Number of turns of the receiving coil Radial distance between transmitting and receiving coils The number of coil layers, etc. The efficiency function described above... and voltage gain function The coil parameters are designed as the objective function. Through simulation verification and considering the requirements of practical application scenarios, this invention selects the coil structure parameters as a single-layer coil and a specific pitch. conductor radius Number of turns of the transmitting coil Number of turns of the receiving coil Distance between coils The coil material is copper Litz wire, and its corresponding theoretical transmission efficiency is... Voltage gain .

[0030] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-rate-of-fire weapon wireless ignition system based on electromagnetic induction coupling, characterized in that: The ignition system has a cylindrical structure, consisting of, from the inside out, a receiving coil frame, a receiving coil, an inner tube, an outer shielding layer, and an outer tube. The transmitting coil is embedded inside the inner tube; The inner tube is made of alumina ceramic; The outer tube is made of titanium alloy; The outer shielding layer is made of a thin layer of aluminum metal. The receiving coil frame is made of ferrite.

2. The high-rate-of-fire weapon wireless ignition system based on electromagnetic induction coupling according to claim 1, characterized in that: The high-rate-of-fire weapon adopts a series-stacked structure design for customized ammunition. The power input circuit of the high-rate-of-fire weapon launcher uses a full-bridge inverter circuit, and pulse width control is used to adjust the equivalent voltage of the inverter output. MOSFETs are used as switching transistors. The rectifier circuit of the high-rate-of-fire weapon receiver uses Schottky diodes as switching transistors.

3. The high-rate-of-fire weapon wireless ignition system based on electromagnetic induction coupling according to claim 1, characterized in that: In the wireless ignition system, the receiving coil transmits energy to the pyrotechnic device of the high-rate-of-fire weapon through a topology circuit, igniting the pyrotechnic device and propelling the projectile.

4. The high-rate-of-fire weapon wireless ignition system based on electromagnetic induction coupling according to claim 3, characterized in that: The circuit topology uses the SS topology as the resonant compensation circuit.

5. The high-rate-of-fire weapon wireless ignition system based on electromagnetic induction coupling according to claim 1, characterized in that: The receiving coil is a single-layer coil with a pitch of [missing information]. coil radius Number of coil turns The coil material is copper Litz wire; The transmitting coil is a single-layer coil with a pitch of [missing information]. coil radius Number of coil turns The coil material is copper Litz wire; Coil distance between receiving coil and transmitting coil .

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