Active trigger structure, fuse and manufacturing process of fuse

Abstract

This invention discloses an active triggering structure, a fuse, and a fuse manufacturing process. The fuse with an active triggering structure includes: a ceramic tube; two sets of end caps fixed to both ends of the ceramic tube using a hermetically sealed process; at least two sets of spaced-apart gradient composite melts suspended parallel inside the ceramic tube; an arc-extinguishing medium covering all the gradient composite melts and filling the voids inside the ceramic tube; and an active triggering module including an embedded sensor embedded in the gradient composite melt, a disconnecting actuator located inside the end caps, and an external control unit. The control unit receives signals from the embedded sensor and controls the disconnecting actuator to disconnect the circuit. This invention achieves both surge protection and high breaking capacity by combining gradient composite melts with a cyclically disconnecting arc-extinguishing medium, providing reliable protection for high-voltage, high-energy scenarios.

Description

Technical Field

[0001] This invention relates to the field of fuse manufacturing technology, and more specifically, to an active triggering structure, a fuse, and a fuse manufacturing process. Background Technology

[0002] With the rapid development of 800V high-voltage platforms for new energy vehicles, smart grids, and high-power industrial equipment, circuit protection systems are facing unprecedentedly stringent challenges. The inherent contradiction between surge protection, high breaking capacity, and cycle life in traditional fuses has become a technical bottleneck restricting the development of high-reliability power supply systems. (1) The trade-off between surge resistance and high breaking capacity: Material limitations: Single melt materials such as pure silver and tin alloys cannot simultaneously meet the requirements of high I. 2 The t-value and the need for rapid interruption. For example, slow-breaking types, such as the Littelfuse 217 series, improve surge tolerance by increasing the melt heat capacity. 2 t=35A 2 However, the breaking capacity is only 35kA, which cannot meet the 100kA breaking requirement of a 1500V photovoltaic system; while fast-breaking type, such as Vishay MOL-100, has a breaking response of <1ms, but weak surge resistance and a false trip rate of >25% when the motor starts.

[0003] Structural defects: Although the double-layer melt solution in patent CN113035816A partially alleviates the contradiction, it does not solve the problems of material gradient design and precise control of weak areas, resulting in insufficient splitting consistency and measured dispersion of ±15%.

[0004] (2) The reliability crisis of arc-extinguishing media for single use: Limitations of physical adsorption: Traditional media such as quartz sand rely on physical adsorption of arc energy, which forms permanent carbonized channels after separation, reducing dielectric strength and resulting in a secondary separation failure rate of >30%.

[0005] Economic losses: In nuclear power / military scenarios, the cost of a single maintenance exceeds $100,000, and under extreme conditions, such as the 300kA pulse of an electromagnetic railgun, the carbonization rate of the medium reaches 100%.

[0006] (3) Response delay of passive circuit breaking: Traditional fuses rely on thermal accumulation effects, with response times >2ms, such as the Schurter SF-20E. When the short-circuit current of an 800V battery pack in a new energy vehicle reaches 20kA / ms, the risk of IGBT module explosion surges, and the damage rate of semiconductor devices increases by 40%.

[0007] (4) Precision bottleneck in manufacturing process: Existing melt stacking processes, such as the Eaton Bussmann HV series, require manual assembly of multiple melt layers, resulting in weak zone positioning deviations > ±200μm, while the design requirement is ±20μm, and dispersed melting points; the arc extinguishing medium filling void rate is >15%, leading to local arc breakdown.

[0008] In view of this, the present invention proposes an innovative solution that integrates gradient material design, self-healing arc extinguishing and intelligent triggering mechanism to achieve compatibility between surge resistance and high breaking capacity, improve cycle life and system safety, and provide reliable protection for high voltage and high energy scenarios. Summary of the Invention

[0009] To address the aforementioned technical problems, this invention provides an active triggering structure, a fuse, and a manufacturing process for the fuse. In this invention's technical solution, an active triggering structure includes: Embedded sensors, specifically fiber gratings etched onto the side of the weak eutectic layer of the gradient composite melt, monitor strain and temperature in real time. The disconnecting actuator, specifically an explosive bolt, is located inside the end cap; The control unit determines that the fusible link is about to melt when the fiber optic grating light offset exceeds the threshold, and triggers the disconnecting actuator to force disconnect the circuit.

[0010] A fuse with an active triggering structure includes: Ceramic tubes; Two sets of end caps are fixed to both ends of the ceramic tube using an airtight sealing process; At least two sets of gradient composite melts, spaced apart, are suspended in parallel inside the ceramic tube; The arc-extinguishing medium is filled throughout, covering all gradient composite melts and filling the voids inside the ceramic tube. The active triggering module includes an embedded sensor embedded in the gradient composite melt, a disconnecting actuator located inside the end cap, and an external control unit. The control unit responds to the embedded sensor signal to trigger the disconnecting actuator disconnecting circuit.

[0011] Furthermore, in the technical solution of the present invention, the gradient composite melt is a five-layer heterogeneous structure, which includes, from the vertical fuse axis, an electrode layer, a buffer layer, a eutectic weak zone layer, a copper skeleton layer, and a platinum-iridium alloy protective layer; a laser-etched V-shaped microcrack is preset in the middle of the upper end face of the eutectic weak zone layer, and the width of the microcrack is 3-7μm.

[0012] Furthermore, in the technical solution of the present invention, the gradient composite melt preparation step includes: ① Under a high vacuum environment, electrode layers are sequentially sputtered and deposited onto the substrate, up to the copper framework layer; ② Use a femtosecond laser to etch microcracks at predetermined positions in the eutectic weak region layer; form a porous structure by heat treatment of the copper skeleton layer (44); ③ Electroplating a platinum-iridium alloy protective layer onto the surface of the copper skeleton layer; ④ Peel the complete five-layer film from the substrate and cut it into a preset shape using a precision laser.

[0013] Furthermore, in the technical solution of the present invention, the eutectic weak zone material is a bismuth-tin-indium alloy, and the weight percentage of bismuth, tin and indium is 50-52:28-32:18-20, with a melting point ≤138℃.

[0014] Furthermore, in the technical solution of the present invention, the arc-quenching medium comprises the following components: Hydrophobically modified silica aerogel matrix; Self-healing microcapsules dispersed in a matrix, with polyurea formaldehyde as the wall material and dicyclopentadiene and Grubbs catalyst as the core material; Boron nitride nanosheets and graphene nanosheets are uniformly dispersed to form a three-dimensional thermally conductive / arc-quenching network.

[0015] Furthermore, in the technical solution of the present invention, by weight percentage: the hydrophobic modified silica aerogel matrix accounts for 60% to 75%, the self-healing microcapsules account for 15% to 25%, the boron nitride nanosheets account for 5% to 15%, and the graphene nanosheets account for 5% to 10%.

[0016] Furthermore, in the technical solution of the present invention, the inner wall of the ceramic tube is etched with a micro pyramid array, the pyramid depth-to-width ratio is 1:2 to 1:4, and the depth is 10-30μm.

[0017] A process for manufacturing a fuse includes the following steps: ①Melt fixing: The prefabricated gradient composite melt is fixed to the lower cap at intervals using a fusible tooling; ② Sleeve filling: Insert a ceramic tube and vibrate to fill the arc-extinguishing medium powder until it completely covers the gradient composite melt; ③Remove tooling: Melt or disassemble the tooling to suspend the gradient composite melt; ④ Cold isostatic pressing: Compacting the arc-extinguishing medium under a hydrostatic pressure of 200-300MPa; ⑤ End cap sealing: The upper end cap is hermetically sealed to the ceramic tube by parallel gap brazing.

[0018] Furthermore, in the technical solution of the present invention, the frequency of vibration filling in step ② is 50-200Hz, and the amplitude is 0.1-0.5mm; the holding time of cold isostatic pressing in step ④ is 5-10 minutes.

[0019] Furthermore, in the technical solution of the present invention, the parallel gap brazing in step ⑤ uses a gold-tin eutectic preform, the brazing temperature is 280-300℃, the pressure is 20-30MPa, and the energizing time is 100-500ms.

[0020] Effective gain: In the technical solution of this invention, the contradiction between fusing accuracy and surge resistance is resolved by using a gradient melt. The Ag-Cu alloy buffer layer has a high specific heat capacity to absorb surge heat energy, and the copper skeleton layer with 40% porosity provides mechanical damping, extending the surge withstand time and greatly improving the surge resistance of the gradient composite melt.

[0021] Meanwhile, the micro pyramid array extends the arc path by 300%, and the graphene nanosheets form a three-dimensional conductive network, accelerating the dissipation of arc energy and improving the breaking ability of gradient composite melts. Finally, the self-healing microcapsules rupture to release DCPD, which polymerizes in situ to fill the erosion pits under the action of Grubbs catalyst. Boron nitride nanosheets repair the thermal conductivity network, and the three-dimensional arc-quenching medium realizes self-healing and global energy management. It can be repeatedly interrupted, greatly extending its service life.

[0022] Other features and advantages of the present invention will be set forth in the following description. Attached Figure Description

[0023] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the fuse structure of the present invention; Figure 2 For the present invention Figure 1 Enlarged structural diagram at point A; Figure 3 For the present invention Figure 1 Enlarged structural diagram at point B; Figure 4 This is a schematic diagram of the fuse manufacturing process of the present invention.

[0025] The components include: 1. Fuse, 2. End cap, 3. Ceramic tube, 4. Gradient composite melt, 41. Electrode layer, 42. Buffer layer, 43. Eutectic weak zone layer, 44. Copper skeleton layer, 45. Platinum-iridium alloy protective layer, 5. Arc extinguishing medium, 6. Breaking actuator, and 7. Embedded sensor. Detailed Implementation

[0026] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0027] In one aspect, this invention provides a fuse 1, comprising: Ceramic tube 3; Two sets of end caps 2 are fixed to both ends of the ceramic tube 3 by an airtight sealing process; At least two sets of gradient composite melts 4 are spaced apart and suspended in parallel inside the ceramic tube 3; The arc-extinguishing medium 5, which is filled as a whole, covers all the gradient composite melt 4 and fills the internal voids of the ceramic tube 3. The active triggering module includes an embedded sensor 7 embedded in the gradient composite melt 4, a disconnecting actuator 6 located inside the end cap 2, and an external control unit. The control unit responds to the signal from the embedded sensor 7 to trigger the disconnecting actuator 6 to disconnect the circuit.

[0028] Please see Figure 3 The gradient composite melt 4 is a five-layer heterogeneous structure, which includes, in sequence along the vertical axis of the fuse 1: an electrode layer 41, a buffer layer 42, a eutectic weak region layer 43, a copper skeleton layer 44, and a platinum-iridium alloy protective layer 45; the upper surface of the eutectic weak region layer 43 is pre-etched with laser-etched V-shaped microcracks with a width of 3-7 μm.

[0029] Specifically, electrode layer 41 is a 90%–10% silver-graphene composite layer with a thickness of 20 μm. Silver-graphene has high electrical and thermal conductivity, enabling rapid heat dissipation. Buffer layer 42 is an 85%–15% silver-copper alloy layer with a thickness of 30 μm, providing surge protection. Eutectic weak region layer 43 is made of bismuth-tin-indium alloy with a weight percentage of 50-52:28-32:18-20 for bismuth, tin, and indium, a melting point ≤138℃, and a thickness of 10 μm, used for low-temperature melting triggering. Copper skeleton layer 44 is a porous copper skeleton with a porosity of 40% and a thickness of 50 μm, used for mechanical support and stress relief. Platinum-iridium alloy protective layer 45 is a platinum-iridium alloy electroplated layer with a thickness of 5 μm, resisting arc erosion and radiation aging.

[0030] In this embodiment, the preparation steps of the gradient composite melt 4 include: ① Under a high vacuum environment, electrode layer 41 to copper framework layer 44 are sequentially sputtered and deposited on the substrate. By precisely controlling the target material and process parameters, the composition and microstructure of each layer are realized, and microcracks are etched at predetermined positions in the eutectic weak region layer 43 using a femtosecond laser to form a precise weak region; and then heat-treated at 400°C in Ar gas for 1 hour to form a copper framework layer 44 with voids. Specifically, the sputtering process parameters for each layer from electrode layer 41 to copper framework layer 44 are shown in the table below: ② A platinum-iridium alloy protective layer 45 is electroplated on the surface of the copper skeleton layer 44: Electroplating solution formulation: Platinum aminosulfonate Pt(NH2SO3)4: 10 g / L; Iridic chloroisocyanuric acid H2IrCl6: 0.6 g / L; Aminosulfonic acid NH2SO3H: 100 g / L, as complexing agent and buffer.

[0031] Solution pH 1.5-2.0, temperature 65±2℃, current density 0.5 A / dm³ 2 Electroplating time: 50 minutes.

[0032] Among these, low current density and heating help improve the density of the coating, avoid voids, and enhance the material's resistance to arc erosion.

[0033] ③ Peel the complete five-layer film from the substrate and cut it into a preset shape using a precision laser.

[0034] Understandably, the melt resistance of the gradient composite melt 4 increases from the electrode layer 41 to the platinum-iridium alloy protective layer 45, thereby optimizing the current distribution; the eutectic weak zone layer 43 is pre-set with microcracks to guide the melting point; the multi-layer melt is used, and the current path is: end cap 2 → electrode layer 41 → buffer layer 42 → eutectic weak zone layer 43 → copper skeleton layer 44 → platinum-iridium alloy protective layer 45 → the other end cap 2, which significantly increases the total length compared to a single layer, extending the material's withstand time under 10 times surge current conditions.

[0035] It should be added that the gradient composite melt 4 is set to have 2-5 groups.

[0036] In this embodiment, the arc-quenching medium 5 comprises the following components: Hydrophobically modified silica aerogel matrix; Self-healing microcapsules dispersed in a matrix, with polyurea formaldehyde as the wall material and dicyclopentadiene DCPD and Grubbs catalyst as the core material; Boron nitride nanosheets and graphene nanosheets are uniformly dispersed to form a three-dimensional thermally conductive / arc-quenching network.

[0037] Specifically, by weight percentage: hydrophobically modified silica aerogel matrix accounts for 60%–75%, self-healing microcapsules account for 15%–25%, boron nitride nanosheets account for 5%–15%, and graphene nanosheets account for 5%–10%.

[0038] In this embodiment, the arc-extinguishing medium preparation process includes: Pre-dispersion: Boron nitride nanosheets (BNNS) and graphene nanosheets (GNP) were placed in a solvent and ultrasonically dispersed to obtain a stable suspension.

[0039] Mixing: The hydrophobically modified silica aerogel powder is thoroughly mixed with the two suspensions mentioned above, and a high-speed shear emulsifier is used to ensure that the nanomaterials are uniformly attached to the aerogel skeleton.

[0040] Drying: Dry at low temperature in a vacuum oven to completely remove the solvent.

[0041] Blending: The dried composite powder and self-healing microcapsules are mixed evenly at low speed in a V-type mixer to avoid damaging the microcapsules by high-speed stirring.

[0042] Sieving: Passing through a 200-mesh sieve yields a final, usable, and free-flowing composite arc-extinguishing medium powder.

[0043] Furthermore, the hydrophobically modified silica aerogel matrix was selected from Zhejiang Nano Technology, model NAG-SH-75, with a contact angle of 158±3°; The self-healing microcapsules are selected from Covestro, model MC-SH-05, with a wall thickness of 200±50nm, a particle size of 15-45μm, a DCPD encapsulation rate of ≥85%, and a catalyst loading of 5-8wt%. The catalyst is Grubbs Catalyst 2nd Generation produced by Merck. After the microcapsules rupture, the catalyst catalyzes the DCPD polymerization reaction to fill the arc erosion pits. The boron nitride nanosheets are selected from Hefei Micro-Nano New Materials, model WN-BN50, with a thermal conductivity of 200 W / m·K, which greatly improves the uniformity of thermal conduction and avoids thermal runaway; the graphene nanosheets are selected from Sixth Element, model SE1232, with an electrical conductivity of 3500 S / m, which accelerates the absorption of arc energy.

[0044] In this embodiment, the inner wall of the ceramic tube 3 is etched with a micro pyramid array, the pyramid having a depth-to-width ratio of 1:2 to 1:4, a depth of 10-30 μm, and a slope angle of 26.5-45°.

[0045] By etching the inner wall of ceramic tube 3 with a femtosecond laser, a pyramid array forms a sawtooth crack propagation path. The grooves with a depth of 10-30 μm force the cracks to repeatedly turn at an inclination angle of 45±5°, extending the actual fracture path. At the same time, the pyramid slopes with an inclination angle of 26.5-45° form a spiral groove. The electric arc rotates and extends along the groove under the drive of the magnetic field, increasing the contact area with the arc-extinguishing medium and realizing arc guidance and energy dissipation. The micro pyramid array increases the effective heat dissipation area and forms a three-dimensional heat-conducting network with boron nitride nanosheets (BNNS). The array structure provides mechanical interlocking anchor points, and the arc-extinguishing medium is embedded in micropores under cold isostatic pressure of 200-300 MPa, enhancing the interfacial bonding strength.

[0046] Another aspect of the present invention provides a process for manufacturing a fuse, comprising the following steps: ①Melt fixing: The prefabricated gradient composite melt 4 is fixed to the lower cap 2 at intervals using a fusible tooling; Specifically, a precision, soluble or detachable temporary fixture, such as one made of PVA plastic, is used. This fixture has at least two sets of precise slots to suspend the prefabricated gradient composite melt 4 in parallel and equidistant positions in the center of the ceramic tube 3. The fixture, which holds the gradient composite melt 4 in place, is then combined with the lower cap 2.

[0047] ② Sleeve filling: Insert ceramic tube 3, and vibrate to fill arc-extinguishing medium powder until it completely covers gradient composite melt 4; Specifically, the ceramic tube 3 is fitted over the entire component, and the prepared arc-extinguishing medium 5 is loaded into a precision quantitative filling device. Under the conditions of 50-200Hz and an amplitude of 0.1-0.5mm, the powder is slowly poured from above into the gap between the ceramic tube 3 and the gradient composite melt 4 through continuous micro-vibration. After filling completely, the port is leveled. Vibration helps the powder to flow freely, ensuring dense filling without bridging or voids.

[0048] ③Remove tooling: Melt or disassemble the tooling to suspend the gradient composite melt 4 in the air; Specifically, the temporary internal fixtures are carefully removed by heating and melting or by precision mechanical disassembly, and the top cap is replaced to complete the initial assembly. At this point, the three molten pieces are suspended and fixed in the center of the tube by the surrounding compacted powder.

[0049] ④ Cold isostatic pressing: The medium is compacted under a hydrostatic pressure of 200-300MPa to extinguish the arc. Specifically, the assembled components are placed in the flexible mold of a cold isostatic press, and a hydrostatic pressure of 200-300 MPa is applied and held for 5-10 minutes. This process thoroughly compacts the loose powder into a solid, tightly bonding it to the melt and the inner wall of the ceramic tube into a unified whole.

[0050] ⑤ End cap sealing: The upper end cap 2 and the ceramic tube 3 are hermetically sealed by parallel gap brazing.

[0051] Specifically, parallel gap brazing is used for final encapsulation. The component is placed on the soldering station, and the electrodes are pressed tightly against the end cap and ceramic tube. A high instantaneous current is applied to heat the gold-tin eutectic preform of the solder layer to 280-300°C above its eutectic point, at a pressure of 20-30 MPa, for 100-500 ms, causing it to melt. Under pressure, the molten solder wets the end face of the ceramic tube and the inner wall of the end cap, forming a strong, airtight metallurgical bond upon cooling.

[0052] This invention also proposes an active triggering structure, please refer to [link / reference]. Figures 1 to 3 ,include: The embedded sensor 7, specifically a fiber optic grating, is located on the side of the eutectic weak region layer 43 to monitor the strain and temperature of the eutectic weak region layer 43 in real time. The disconnecting actuator 6 is located inside the end cap 2 and is specifically an explosion bolt. The control unit determines that the eutectic weak layer 43 is about to melt when the fiber optic grating light angle offset is greater than the threshold, and triggers the interruption actuator 6 to force the interruption circuit within 0.5ms.

[0053] In this embodiment, the grating direction is perpendicular to the current direction. Specifically, the grating is a Bragg grating with a length of 5.0±0.1mm and a period of 530±1nm.

[0054] Furthermore, a grating is set on the side of the eutectic weak region layer 43 by femtosecond laser tilt projection etching to detect the deformation of the eutectic weak region layer 43. The specific parameters are: laser energy 0.48-0.52mJ, tilt angle 74.8°-75.2°, helium cooling flow rate 8-12L / min, and HF etching temperature 24.9-25.1℃.

[0055] It should be noted that the fiber grating is placed in the sidewall region corresponding to the location of the V-shaped microcrack to improve monitoring accuracy and response rate.

[0056] It is understandable that the eutectic weak layer 43 expands and deforms under heat, and the microcracks in the eutectic weak layer 43 propagate. The fiber is stretched, which increases the grating period and shifts the light diffraction angle. At the same time, the melt heats up, the fiber temperature rises, and the refractive index increases. Combined with the thermal expansion of the material, this causes the light diffraction angle to shift. When the shift reaches the threshold, the control unit triggers the interruption actuator 6 to force the interruption circuit. This allows the circuit to be interrupted before the heat of the gradient composite melt 4 accumulates to the point of complete melting, thereby reducing the interruption response time.

[0057] To further understand the present invention, the following description, in conjunction with embodiments, illustrates a fuse with an active triggering structure provided by the present invention. The scope of protection of the present invention is not limited by the following embodiments.

[0058] Experimental Example 1 Preparation of gradient composite melts: ① Under high vacuum environment, an electrode layer with a thickness of 20μm was sequentially sputtered and deposited on the substrate using a composite target: Ag90at% and C10at%, sputtering power DC: 2.0KW, and deposition time 2000s; A 30μm thick silver-copper alloy layer was used with an alloy target: Ag. 85 Cu 15 Sputtering power DC: 1.5KW, deposition time 3750s; A 10μm thick eutectic weak region layer was constructed using an alloy target Bi. 52 Sn 28 In 20 The sputtering power DC is 0.8KW, the deposition time is 2000s, the laser etching of 5μm microcracks is performed, and the femtosecond laser tilt projection etching is performed, with a laser energy of 0.48mJ, a tilt angle of 74.8°, a helium cooling flow rate of 8L / min, and an HF etching temperature of 24.9℃. A Bragg grating is set on the side of the eutectic weak region layer. A 50μm thick copper framework layer was created using a high-purity Cu target, with a sputtering power of DC 2.0KW and a deposition time of 5000s, followed by Ar gas treatment at 400°C for 1h, resulting in a porosity of 40%. ② A 5μm thick platinum-iridium alloy protective layer is electroplated onto the surface of the copper framework layer. The solution pH is 1.5-2.0, the temperature is 65±2℃, and the current density is 0.5 A / dm³. 2 Electroplating time: 50 min; ③ Peel the complete five-layer film from the substrate and cut it into a preset shape using a precision laser.

[0059] Experiment Example 2 Preparation of gradient composite melts: ① Under high vacuum environment, an electrode layer with a thickness of 20μm was sequentially sputtered and deposited on the substrate using a composite target: Ag90at% and C10at%, sputtering power DC: 2.0KW, and deposition time 2000s; A 30μm thick silver-copper alloy layer was used with an alloy target: Ag. 85 Cu 15 Sputtering power DC: 1.5KW, deposition time 3750s; The 10μm thick eutectic weak region layer uses an alloy target Bi 50 Sn 30 In 20The sputtering power was DC: 0.8KW, the deposition time was 2100s, and 5μm microcracks were etched by laser. The microcracks were etched by femtosecond laser tilting projection, with laser energy of 0.52mJ, tilt angle of 75.2°, helium cooling flow rate of 12L / min, and HF etching temperature of 25.1℃. A Bragg grating was set on the side of the eutectic weak region layer. A 50μm thick copper framework layer was created using a high-purity Cu target, with a sputtering power of DC 2.0KW and a deposition time of 5000s, followed by Ar gas treatment at 400°C for 1h, resulting in a porosity of 40%. ② A 5μm thick platinum-iridium alloy protective layer is electroplated onto the surface of the copper framework layer. The solution pH is 1.5-2.0, the temperature is 65±2℃, and the current density is 0.5 A / dm³. 2 Electroplating time: 50 min; ③ Peel the complete five-layer film from the substrate and cut it into a preset shape using a precision laser.

[0060] Experimental Example 3 Preparation of arc-quenching medium: Pre-dispersion: 5% boron nitride nanosheets (BNNS) and 5% graphene nanosheets (GNP) were placed in acetone solvent at a solid-liquid ratio of 1:10 and ultrasonically dispersed to obtain a stable suspension. Mixing: 70% by mass of hydrophobic modified silica aerogel powder is thoroughly mixed with the two suspensions mentioned above, and a high-speed shear emulsifier is used to ensure that the nanomaterials are uniformly attached to the aerogel skeleton. Drying: Dry thoroughly in a vacuum oven at 0.1 Pa and 5°C to remove the solvent; Blending: The dried composite powder and 20% by mass of self-healing microcapsules are mixed evenly at low speed in a V-type mixer; Sieving: Pass the material through a 200-mesh sieve to obtain arc-extinguishing medium powder.

[0061] Experiment Example 4 Preparation of arc-quenching medium: Pre-dispersion: 15% boron nitride nanosheets (BNNS) and 10% graphene nanosheets (GNP) were placed in acetone solvent at a solid-liquid ratio of 1:10 and ultrasonically dispersed to obtain a stable suspension. Mixing: 60% by mass of hydrophobic modified silica aerogel powder is thoroughly mixed with the two suspensions mentioned above, and a high-speed shear emulsifier is used to ensure that the nanomaterials are uniformly attached to the aerogel skeleton. Drying: Dry thoroughly in a vacuum oven at 0.1 Pa and 5°C to remove the solvent; Blending: The dried composite powder and 15% by mass of self-healing microcapsules are mixed evenly at low speed in a V-type mixer; Sieving: Pass the material through a 200-mesh sieve to obtain arc-extinguishing medium powder.

[0062] Example 1 Fuse manufacturing: ① The three sets of prefabricated gradient composite melts from Experiment Example 1 were fixed to the lower cap at intervals using temporary PVA plastic fixtures, ensuring they were suspended parallel and equidistantly in the center of the ceramic tube. The fixtures fixing the gradient composite melts were then combined with the lower caps, and the ceramic tube was then placed over the entire assembly.

[0063] ② Sleeve filling: Insert the ceramic tube and load the arc-extinguishing medium prepared in Experiment 3 into the precision quantitative filling equipment. Under the condition of continuous micro-vibration, the frequency is 100Hz and the amplitude is 0.1mm. The powder is slowly poured into the gap between the ceramic tube and the gradient composite melt from above. After filling it completely, the port is scraped flat.

[0064] ③The gradient composite melt is suspended in the air by disassembling the tooling with precision machinery; ④ Place the assembled components into the flexible mold of the cold isostatic press, apply a hydrostatic pressure of 200-300 MPa, and hold the pressure for 5-10 minutes.

[0065] ⑤ Parallel gap brazing is used for final encapsulation. The component is placed on the soldering station, and the electrodes are pressed tightly against the end caps and ceramic tubes. A large instantaneous current is applied to heat the gold-tin eutectic preform of the solder layer to 280°C above its eutectic point, with a pressure of 20MPa and an energizing time of 100-500ms.

[0066] Example 2 Fuse manufacturing: ① The three sets of prefabricated gradient composite melts from Experiment Example 2 were fixed to the lower cap at intervals using temporary PVA plastic fixtures, ensuring they were suspended parallel and equidistantly in the center of the ceramic tube. The fixtures fixing the gradient composite melts were then combined with the lower caps, and the ceramic tube was then placed over the entire assembly.

[0067] ② Sleeve filling: Insert the ceramic tube and load the arc-extinguishing medium prepared in Experiment Example 4 into the precision quantitative filling equipment. Under the condition of continuous micro-vibration, the frequency is 100Hz and the amplitude is 0.1mm. The powder is slowly poured into the gap between the ceramic tube and the gradient composite melt from above. After filling it completely, the port is scraped flat.

[0068] ③The gradient composite melt is suspended in the air by disassembling the tooling with precision machinery; ④ Place the assembled components into the flexible mold of the cold isostatic press, apply a hydrostatic pressure of 200 MPa, and hold the pressure for 8 minutes.

[0069] ⑤ Parallel gap brazing is used for final encapsulation. The component is placed on the soldering station, and the electrodes are pressed against the end caps and ceramic tubes respectively. A large instantaneous current is applied to heat the gold-tin eutectic preform of the solder layer to 280°C above its eutectic point, with a pressure of 20MPa and an energizing time of 200ms.

[0070] Example 3 Fuse manufacturing: ① The three sets of prefabricated gradient composite melts from Experiment Example 1 were fixed to the lower cap at intervals using temporary PVA plastic fixtures, ensuring they were suspended parallel and equidistantly in the center of the ceramic tube. The fixtures fixing the gradient composite melts were then combined with the lower caps, and the ceramic tube was then placed over the entire assembly.

[0071] ② Sleeve filling: Insert the ceramic tube and load the arc-extinguishing medium prepared in Experiment Example 4 into the precision quantitative filling equipment. Under the condition of continuous micro-vibration, the frequency is 100Hz and the amplitude is 0.1mm. The powder is slowly poured into the gap between the ceramic tube and the gradient composite melt from above. After filling it completely, the port is scraped flat.

[0072] ③The gradient composite melt is suspended in the air by disassembling the tooling with precision machinery; ④ Place the assembled components into the flexible mold of the cold isostatic press, apply a hydrostatic pressure of 200 MPa, and hold the pressure for 8 minutes.

[0073] ⑤ Parallel gap brazing is used for final encapsulation. The component is placed on the soldering station, and the electrodes are pressed against the end caps and ceramic tubes respectively. A large instantaneous current is applied to heat the gold-tin eutectic preform of the solder layer to 280°C above its eutectic point, with a pressure of 20MPa and an energizing time of 200ms.

[0074] Example 4 Fuse manufacturing: ① The three sets of prefabricated gradient composite melts from Experiment Example 2 were fixed to the lower cap at intervals using temporary PVA plastic fixtures, ensuring they were suspended parallel and equidistantly in the center of the ceramic tube. The fixtures fixing the gradient composite melts were then combined with the lower caps, and the ceramic tube was then placed over the entire assembly.

[0075] ② Sleeve filling: Insert the ceramic tube and load the arc-extinguishing medium prepared in Experiment 3 into the precision quantitative filling equipment. Under the condition of continuous micro-vibration, the frequency is 100Hz and the amplitude is 0.1mm. The powder is slowly poured into the gap between the ceramic tube and the gradient composite melt from above. After filling it completely, the port is scraped flat.

[0076] ③The gradient composite melt is suspended in the air by disassembling the tooling with precision machinery; ④ Place the assembled components into the flexible mold of the cold isostatic press, apply a hydrostatic pressure of 200 MPa, and hold the pressure for 8 minutes.

[0077] ⑤ Parallel gap brazing is used for final encapsulation. The component is placed on the soldering station, and the electrodes are pressed against the end caps and ceramic tubes respectively. A large instantaneous current is applied to heat the gold-tin eutectic preform of the solder layer to 280°C above its eutectic point, with a pressure of 20MPa and an energizing time of 200ms.

[0078] Comparative Example 1 The commercially available alumina bushing fuse is from Littelfuse, model LV Spd series.

[0079] Comparative Example 2 ① The three sets of prefabricated gradient composite melts from Experiment Example 2 were fixed to the lower cap at intervals using temporary PVA plastic fixtures, ensuring they were suspended parallel and equidistantly in the center of the ceramic tube. The fixtures with the fixed gradient composite melts were then combined with the lower caps, and the ceramic tube was then placed over the entire assembly. ② Sleeve filling: Insert the ceramic tube, load the arc-extinguishing sand into the precision quantitative filling equipment, and under the condition of continuous micro-vibration at a frequency of 100Hz and an amplitude of 0.1mm, slowly pour the powder from above into the gap between the ceramic tube and the gradient composite melt. After filling it completely, scrape the end level. The arc-quenching sand used was selected from Sibelco, model QF50. ③The gradient composite melt is suspended in the air by disassembling the tooling with precision machinery; ④ Place the assembled components into the flexible mold of the cold isostatic press, apply a hydrostatic pressure of 200 MPa, and hold the pressure for 8 minutes; ⑤ Parallel gap brazing is used for final encapsulation. The component is placed on the soldering station, and the electrodes are pressed against the end caps and ceramic tubes respectively. A large instantaneous current is applied to heat the gold-tin eutectic preform of the solder layer to 280°C above its eutectic point, with a pressure of 20MPa and an energizing time of 200ms.

[0080] Comparative Example 3 ① Secure the three sets of ordinary melts to the lower cap at intervals using temporary PVA plastic fixtures, ensuring they are parallel and equidistantly suspended in the center of the ceramic tube. Combine the fixtures holding the gradient composite melts in place with the lower cap, and then attach the ceramic tube to the outside of the entire assembly; The ordinary melt was selected from the manufacturer Vishay, model MOL-100; ② Sleeve filling: Insert the ceramic tube, load the arc extinguishing medium prepared in Experiment Example 3 into the precision quantitative filling equipment, under the condition of continuous micro-vibration with a frequency of 100Hz and an amplitude of 0.1mm, slowly pour the powder from above into the gap between the ceramic tube and the gradient composite melt, and after filling it completely, scrape the end level. ③The gradient composite melt is suspended in the air by disassembling the tooling with precision machinery; ④ Place the assembled components into the flexible mold of the cold isostatic press, apply a hydrostatic pressure of 200 MPa, and hold the pressure for 8 minutes; ⑤ Parallel gap brazing is used for final encapsulation. The component is placed on the soldering station, and the electrodes are pressed against the end caps and ceramic tubes respectively. A large instantaneous current is applied to heat the gold-tin eutectic preform of the solder layer to 280°C above its eutectic point, with a pressure of 20MPa and an energizing time of 200ms.

[0081] Test example: The breaking capacity of the fuses prepared in Examples 1-4 and the fuses in Comparative Examples 1-3 was tested according to the testing standard IEC 60269-1, and the test results are recorded in Table 1.

[0082] The surge resistance of the fuses prepared in Examples 1-4 and the fuses in Comparative Examples 1-3 was tested according to the test standard UL 248-12, and the test results are recorded in Table 1.

[0083] The breaking response time of the fuses prepared in Examples 1-4 and Comparative Examples 1-3 was tested using a high-speed camera, and the test results are recorded in Table 1.

[0084] The lifespan of the fuses prepared in Examples 1-4 and the fuses in Comparative Examples 1-3 were tested according to the EIA-364-1000 test standard, and the test results are recorded in Table 1.

[0085] Table 1. Performance Test Statistics of Examples and Comparative Examples In summary, this invention provides an active triggering structure that uses an embedded sensor 7, namely a fiber optic grating, to monitor the strain of the eutectic weak layer 43 in real time, predicting the triggering of the breaking actuator 6 before melting and breaking. This active breaking occurs before the heat of the gradient composite melt accumulates to a limit value, preventing explosion and combustion. The surge resistance is improved by using a five-layer gradient composite melt. The Ag-Cu alloy buffer layer efficiently absorbs surge heat energy due to its high specific heat capacity, while the porous copper skeleton layer with a porosity of 40% significantly prolongs the energy release time through a unique mechanical damping effect. The synergistic effect of the two layers greatly increases the surge withstand time to nearly 2ms@10In, as shown in Table 1, Example 1. The surge resistance is more than 4 times that of the conventional melt (Comparative Example 1, Table 1). In terms of breaking capacity, the micro-pyramid array structure physically extends the arc path by 300%, forcing the arc to fully extend. Simultaneously, graphene nanosheets form a three-dimensional conductive network in the arc-extinguishing medium, improving arc energy dissipation efficiency by 230%. As shown in Table 1, this design enables a breaking capacity exceeding 100kA; Example 1 in Table 1 shows 102kA, fully meeting the extreme breaking requirements of a 1500V photovoltaic system. Finally, there is the three-dimensional self-healing arc-extinguishing mechanism. When an electric arc occurs, the self-healing microcapsules rapidly rupture to release DCPD monomers, which then polymerize in situ under the action of a Grubbs catalyst, precisely filling the arc erosion pits. Simultaneously, boron nitride nanosheets promptly repair the thermally conductive network damaged by high temperatures, restoring the dielectric insulation strength. This mechanism allows the fuse to achieve more than 5 repeated breaks while maintaining a breaking capacity of 102kA (see Table 1, Example 1), and its lifespan is 5-8 times that of conventional fuses (see Table 1, Comparative Example 2).

[0086] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A fuse (1) characterized in that, include: Ceramic tube (3); Two sets of end caps (2) are fixedly installed at both ends of the ceramic tube (3) by an airtight sealing process; At least two sets of gradient composite melts (4), and several sets of the gradient composite melts (4) are suspended parallel to each other inside the ceramic tube (3); The arc-extinguishing medium (5) covers all the gradient composite melt (4) and fills the internal voids of the ceramic tube (3); Actively triggered structure; The gradient composite melt (4) is a five-layer heterogeneous structure, which includes, in sequence along the direction perpendicular to the fuse (1): an electrode layer (41), a buffer layer (42), a eutectic weak region layer (43), a copper skeleton layer (44), and a platinum-iridium alloy protective layer (45); a laser-etched V-shaped microcrack is preset in the middle of the upper end face of the eutectic weak region layer (43), and the width of the microcrack is 3-7 μm; The active triggering structure includes: Embedded sensors (7), including fiber optic gratings, are used to monitor the strain and temperature of the eutectic weak region layer (43) in real time; Specifically, the grating is a Bragg grating with a length of 5.0±0.1 mm and a period of 530±1 nm. The disconnecting actuator (6) is located inside the end cap (2) to control the disconnection of the circuit. An external control unit is used to receive signals from the embedded sensor (7) and send instructions to the disconnect actuator (6) to force disconnect the circuit.

2. The fuse of claim 1, wherein The eutectic weak region layer (43) is made of bismuth-tin-indium alloy, and the weight percentage of bismuth, tin and indium is 50-52:28-32:18-20. The melting point of the eutectic weak region layer (43) is ≤138℃.

3. The fuse of claim 2, wherein, The preparation steps of the gradient composite melt (4) include: ① Under a high vacuum environment, an electrode layer (41), a buffer layer (42), a eutectic weak region layer (43), and a copper skeleton layer (44) are sequentially sputtered and deposited on the substrate. ② Use a femtosecond laser to etch microcracks at predetermined positions in the eutectic weak region layer (43); and use heat treatment to make the copper skeleton layer (44) have a porous structure; ③ Electroplating a platinum-iridium alloy protective layer (45) onto the surface of the copper skeleton layer (44); ④ Peel the complete five-layer film from the substrate and cut it into a preset shape using a precision laser.

4. The fuse of claim 1, wherein The arc-quenching medium (5) comprises the following components: Hydrophobically modified silica aerogel matrix; Self-healing microcapsules, with polyurea formaldehyde as the wall material and dicyclopentadiene and Grubbs catalyst as the core material; Boron nitride nanosheets and graphene nanosheets are uniformly dispersed to form a three-dimensional thermally conductive / arc-quenching network.

5. The fuse of claim 4, wherein, By weight percentage: hydrophobic modified silica aerogel matrix accounts for 60%–75%, self-healing microcapsules account for 15%–25%, boron nitride nanosheets account for 5%–15%, and graphene nanosheets account for 5%–10%.

6. The fuse of claim 1, wherein The inner wall of the ceramic tube (3) is etched with a micro pyramid array, the pyramid having a depth-to-width ratio of 1:2-4, a depth of 10-30μm, and an inclination angle of 26.5-45°.

7. A manufacturing process for a fuse as described in any one of claims 1-6, characterized in that, Includes the following steps: ①Melt fixing: The prefabricated gradient composite melt (4) is fixed to the lower cap (2) by means of a fusible tooling interval; ② Sleeve filling: Insert ceramic tube (3), and vibrate to fill arc extinguishing medium powder until the gradient composite melt (4) is completely covered; ③Remove tooling: Melt or disassemble the tooling to obtain the workpiece; ④ Cold isostatic pressing: Place the workpiece from step ③ under a hydrostatic pressure of 200-300MPa for 5-10 minutes; ⑤ End cap sealing: The upper end cap (2) and the ceramic tube (3) are hermetically sealed by parallel gap brazing.

8. The process for the production of a fuse according to claim 7, characterized in that, The vibration filling frequency in step ② is 50-200Hz, and the amplitude is 0.1-0.5mm.

9. The process for the production of a fuse according to claim 7, characterized in that, The parallel gap brazing in step ⑤ uses a gold-tin eutectic preform, with a brazing temperature of 280-300℃, a pressure of 20-30MPa, and an energizing time of 100-500ms.

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