A silver-based fuse protection device and circuit fault detection method

Abstract

This invention relates to the field of fuse technology, specifically to a silver-based fuse wire protection device and a circuit fault detection method. The device includes an insulator fuse holder and a protective shell, which is rotatably mounted on one side of the insulator fuse holder via a rotating shaft. A fuse wire passes through the inner cavity of the protective shell and supports it. The terminals of the fuse wire extend out of the protective shell and are fixed to the insulator fuse holder. Current flows through the insulator fuse holder, through the terminals, and through the fuse wire to form an electrical path. The fuse wire includes several fusing sections and several connecting sections, with the fusing sections connected to the connecting sections. A receiving plate is located on one side of the protective shell, with an outlet on the protective shell corresponding to the position of the fusing section, facing the surface of the receiving plate. The outlet is used to discharge vaporized fusing material. The melting point of the fusing material is lower than that of the connecting material, enabling visual observation of the cause of the circuit fault.

Description

Technical Field

[0001] This invention relates to the field of fuse technology, and in particular to a silver-based fuse wire protection device and a circuit fault detection method. Background Technology

[0002] In power systems, fuses are a key protective component. Their core function is to quickly cut off the current by melting their fuse wires when a circuit experiences an overload or short circuit, thereby protecting the safety of downstream electrical equipment and lines.

[0003] In existing technologies, fuse activation indicators typically rely on the popping of mechanical markers or color changes for detection. These methods can clearly inform maintenance personnel that a circuit fault has occurred. Fuse activation can be caused by three completely different reasons: prolonged overload, momentary short circuit, or abnormal temperature rise caused by excessive local contact resistance due to loose connections, oxidation, or other reasons. However, with traditional fuses, regardless of the cause of the fuse failure, the final external state is often the same or very similar. This makes it impossible for maintenance personnel to intuitively determine the root cause of the fault based solely on the damage to the fuse body. When replacing the fuse wire, it is easy to use the wrong fuse material, leading to a secondary fault in the circuit. Summary of the Invention

[0004] Therefore, the purpose of this invention is to overcome the problem that in the prior art, maintenance personnel cannot intuitively determine the specific cause of the fault in a part of the circuit by simply looking at the fuse's blown state, and that it is easy to use the wrong fuse material when replacing the fuse, which may lead to a secondary fault in the circuit. Therefore, a silver-based fuse protection device and circuit fault detection method are proposed, which can specifically determine the main cause of the fuse blown, and reduce the probability of secondary faults when replacing the fuse.

[0005] To address the aforementioned technical problems, this invention provides a silver-based fuse protection device, comprising an insulator fuse holder, and further comprising:

[0006] A protective shell is rotatably mounted on one side of the insulator fuse holder via a rotating shaft disposed on the insulator fuse holder;

[0007] A fuse, which penetrates the inner cavity of the protective shell and supports the protective shell, has its terminals extending out of the protective shell and fixed to the insulator fuse holder. Current flows through the insulator fuse holder, through the terminals, and through the fuse to form an electrical path. The fuse includes several fusing parts and several connecting parts, and the fusing parts are connected to the connecting parts.

[0008] A receiving plate is disposed on one side of the protective shell, and an exhaust port is opened on the protective shell at a position corresponding to the position of the fusible part, facing the surface of the receiving plate. The exhaust port is used to discharge the vaporized fusible part material.

[0009] Wherein, the melting point of the material of the fuse portion is lower than that of the material of the connecting portion, the terminal is made of the same material as the fuse portion, when the current raises the temperature of the fuse portion to a first temperature, the terminal melts, when the current raises the temperature of the fuse portion to a second temperature, the terminal and the fuse portion melt, when the current raises the temperature of the fuse portion to a third temperature, the material of the fuse portion vaporizes, moves and adheres to the surface of the receiving plate, the first temperature is lower than the second temperature, and the second temperature is lower than the third temperature.

[0010] In one embodiment of the present invention, the device further includes a visual inspection module, which includes a camera and a photovoltaic panel fixed on the surface of the receiving plate and connected to the camera. The camera is disposed on the insulator fuse holder and faces the surface of the receiving plate, and is used to detect whether the surface of the photovoltaic panel is covered by the material of the fused portion.

[0011] In one embodiment of the present invention, the cross-sectional diameter of the fused portion is smaller than the cross-sectional diameter of the connecting portion.

[0012] In one embodiment of the present invention, a flame-retardant coating is applied to the connection between the fused portion and the connecting portion.

[0013] In one embodiment of the present invention, when the fuse supports the protective shell, the protective shell is tilted relative to the vertical direction, and when the fuse or the terminal is melted, the protective shell rotates toward its tilting direction.

[0014] In one embodiment of the present invention, the width of the discharge port is greater than the width of the fusible portion, and the ratio of the width of the discharge port to the width of the fusible portion is at least 3 times.

[0015] In one embodiment of the present invention, a circuit fault detection method is proposed, based on a silver-based fuse protection device. The detection method includes:

[0016] S1: Fix the terminal of the fuse to the insulator fuse holder, so that the fuse passes through the protective shell and is taut, limiting the protective shell;

[0017] S2: When current flows through, the fuse melts, the protective shell loses its limiting force and rotates around the axis;

[0018] S3: When the fuse breaks, the vapor generated by vaporization passes through the discharge port and adheres to the surface of the receiving plate;

[0019] S4: The steam condenses and forms a solid. At this time, the operator determines the cause of the fuse blown as short based on the solid adhesion area on the surface of the receiving plate.

[0020] In one embodiment of the present invention, the detection method may further include:

[0021] S3-1: When the fuse section melts, it does not generate or generates only a small amount of vaporized steam, and all of the fuse sections melt;

[0022] S3-2: At this point, the staff determined that the fuse blown was not due to overload, based on the fact that there was no solid or only a very small amount of solid adhering to the surface of the receiving plate.

[0023] In one embodiment of the present invention, the detection method may further include:

[0024] S3-3: After the fuse blows, the severe ablation point of the fuse is located at the root of the terminal, and there is no significant adhesion layer in the receiving plate area corresponding to the discharge port on the protective shell.

[0025] S3-4: At this time, the staff determines that the cause of the fuse failure is an increase in local resistance based on the fuse failure status of the terminal.

[0026] In one embodiment of the present invention, the fusible part is made of silver-based material, the connecting part is made of copper-based material, and the vapor generated by the silver-based material is gaseous silver.

[0027] Compared with the prior art, the above-described technical solution of the present invention has the following advantages:

[0028] The silver-based fuse protection device and circuit fault detection method described in this invention enable on-site identification of the root cause of circuit faults. Existing fuses can only convey the single information that a fuse has been blown, and cannot distinguish whether the nature of the fault that caused the blow is a short circuit with huge energy and instantaneous, an overload with continuously accumulating energy, or a local overheating caused by improper installation. This invention converts the differentiated energy released by faults of different natures into visible physical state signals, so that maintenance personnel can accurately distinguish three typical faults—short circuit, overload, and local resistance increase—by visual observation without any professional instruments.

[0029] Specifically, the protective housing is rotatable via a shaft and is supported and limited by the fuse. The rotation of the protective housing indicates whether the fuse has blown. The fuse comprises several fusing sections and connecting sections, with the fusing section material having a lower melting point than the connecting section. This design ensures that fault-induced heat is preferentially and controllably concentrated at the preset fusing section, providing a stable physical basis for subsequent diagnosis. The protective housing has an exhaust port facing the receiving board, allowing for differentiation between high-energy short circuits and low-energy overloads based on whether vapor from the fusing section is sprayed onto the receiving board. Since the terminals and fusing sections are made of the same material, and have the same melting point, their drastically different heat dissipation conditions allow for differentiating heat sources. When heat originates from the overall current, the fusing section with poor heat dissipation melts first; when heat originates from the terminal contact point, the terminal with a blocked heat dissipation path melts first. This can be used to distinguish whether localized resistance increases leading to temperature rise. Thus, three states are achieved, distinguishing between short circuits, overloads, and localized temperature rises, providing a visual differentiation of circuit faults. Attached Figure Description

[0030] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0031] Figure 1 This is a schematic diagram of the structure of a silver-based fuse protection device in a preferred embodiment of the present invention. Figure 1 ;

[0032] Figure 2 This is a schematic diagram of the structure of a silver-based fuse protection device in a preferred embodiment of the present invention. Figure 2 ;

[0033] Figure 3 This is a schematic diagram of the protective shell portion in a preferred embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the fuse portion in a preferred embodiment of the present invention;

[0035] Figure 5 This is a cross-sectional schematic diagram of the protective shell portion in a preferred embodiment of the present invention.

[0036] Explanation of reference numerals on the accompanying drawings:

[0037] 1. Insulator fuse holder; 11. Receiver board; 12. Visual inspection module; 121. Camera; 122. Photovoltaic panel;

[0038] 2. Protective casing; 21. Discharge port;

[0039] 3. Fuse; 31. Terminal; 32. Fuse break; 33. Connecting part. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0041] The purpose of this invention is to address the problem that in the prior art, maintenance personnel cannot intuitively determine the specific cause of a circuit fault simply by observing the fuse's blown state. Furthermore, when replacing the fuse 3, it is easy to use the wrong fuse 3 material, leading to a secondary fault in the circuit. Therefore, this invention proposes a silver-based fuse 3 protection device and a circuit fault detection method, which can specifically determine the main cause of the fuse 3 blown, thereby reducing the probability of secondary faults when replacing the fuse 3.

[0042] refer to Figure 1 , 4 As shown in Figure 5, a silver-based fuse wire 3 protection device is proposed, including an insulator fuse holder 1. The device further includes: a protective shell 2, which is rotatably mounted on one side of the insulator fuse holder 1 via a rotating shaft mounted on the insulator fuse holder 1; a fuse wire 3, which penetrates the inner cavity of the protective shell 2 and supports the protective shell 2, with terminals 31 of the fuse wire 3 extending out of the protective shell 2 and fixed to the insulator fuse holder 1. Current flows through the insulator fuse holder 1, through the terminals 31, and through the fuse wire 3 to form an electrical path. The fuse wire 3 includes several fusing parts 32 and several connecting parts 33, with the fusing parts 32 connected to the connecting parts 33; and a receiving plate 11, which is disposed on one side of the protective shell 2, with the positions on the protective shell 2 corresponding to the positions of the fusing parts 32. An outlet 21 is provided facing the surface of the receiving plate 11. The outlet 21 is used to discharge the vaporized material of the fuse part 32. The melting point of the material of the fuse part 32 is lower than that of the material of the connecting part 33. The terminal 31 is made of the same material as the fuse part 32. When the current raises the temperature of the fuse part 32 to a first temperature, the terminal 31 melts and the fuse part 32 partially melts but does not melt. When the current raises the temperature of the fuse part 32 to a second temperature, both the terminal 31 and the fuse part 32 melt. When the current raises the temperature of the fuse part 32 to a third temperature, the material of the fuse part 32 vaporizes, moves, and adheres to the surface of the receiving plate 11. The first temperature is lower than the second temperature, and the second temperature is lower than the third temperature.

[0043] refer to Figure 1 , 4As shown in Figure 5, the insulator fuse holder 1 serves as the mechanical support foundation and electrical installation base of the device. Its core function is to provide reliable insulation performance, ensuring that no leakage or breakdown occurs between the live parts of the device and the grounded shell or mounting bracket under high voltage conditions, thus guaranteeing operational safety and system stability. The protective shell 2 is rotatably connected to one side of the insulator fuse holder 1. When the internal fuse 3 melts, the protective shell 2 loses the tension support of the fuse 3 and is released from the "tightened" fixed state, allowing it to rotate around the axis under the action of gravity or other auxiliary forces. This rotation is a visible change in mechanical position, which can be observed intuitively from a distance. The fuse 3, as a conductive and temperature-sensing element, is the core functional component of the device. During normal operation, it carries the rated current. The fuse 3 can also serve as a mechanical support for the protective shell 2, maintaining the protective shell 2 in its initial working position by being tightened, thus coupling the electrical state and mechanical state together. Once the electrical state changes, the mechanical state will inevitably change immediately, ensuring the immediacy and absolute synchronization of the indication.

[0044] refer to Figure 1 , 3As shown in Figures 4 and 5, to ensure the fuse 3 melts, it is divided into several fusing sections 32 and several connecting sections 33, which are alternately connected. When a fault current passes through, heat will preferentially accumulate in these fusing sections 32, causing them to melt. Furthermore, the melting point of the material in the fusing sections 32 is lower than that of the material in the connecting sections 33. This ensures that, under overcurrent conditions, the fusing sections 32 will reach their melting point before the connecting sections 33. This confines the melting process to the preset fusing section 32, guaranteeing the accurate melting point. Qualitatively, while terminal 31 and fuse 32 have the same melting point, their heat capacity and heat dissipation conditions are drastically different. Terminal 31 is typically larger and tightly connected to the insulator fuse holder 1 by bolts, resulting in excellent heat dissipation. Fuse 32, suspended in the air within the protective shell 2, dissipates heat more slowly. Therefore, under the same current but longer heating conditions, such as current overload, the poorly dissipated fuse 32 will reach its melting point and melt first. Under the instantaneous high current impact of a short circuit, heat is rapidly generated at all points. However, due to the potentially larger cross-sectional area and more complex thermal inertia of terminal 31, fuse 32 may be more sensitive and vaporize first. More importantly, when the fault originates from excessive local resistance at the terminal 31 connection point, heat is highly concentrated at the contact point between terminal 31 and insulator fuse holder 1. Because this heat source is close to the root of terminal 31, and terminal 31 itself has a relatively large heat capacity but its heat dissipation path is obstructed, heat will preferentially accumulate at this accumulation point, leading to severe ablation, melting, or even breakage at the root of terminal 31. Meanwhile, although heat... The current will be conducted along the fuse 3 to the fuse part 32. However, since the fault current may not significantly exceed the rated value, the heat conducted to the fuse part 32 and the Joule heat generated by the fuse part 32 itself are insufficient to cause it to completely melt as if it had experienced an overload or short circuit. Thus, three different melting modes are created according to the three circuit conditions: when overloaded, the terminal 31 and the fuse part 32 melt but do not vaporize; when short-circuited, the fuse part 32 vaporizes; and when the local resistance is too high, only the terminal 31 melts, and the fuse part 32 melts but does not melt.

[0045] refer to Figure 1 , 3 As shown in Figures 4 and 5, the three situations are essentially caused by different temperature gradients due to current, resulting in different outcomes. Therefore, there are a first temperature, a second temperature, and a third temperature. The first temperature corresponds to the partial overheating and melting of terminal 31. The second temperature corresponds to the melting of the fuse part 32 but without vaporization, which typically corresponds to high-energy overloads or small short-circuit faults. The third temperature corresponds to the violent vaporization of the fuse part 32, which is a distinct characteristic of extremely large short-circuit currents. By observing whether terminal 31 melts, fuse part 32 melts, or fuse part 32 vaporizes and sprays out, the root causes of the above three faults can be intuitively distinguished.

[0046] refer to Figure 1 , 2As shown in Figure 3, the vaporization of the fuse section 32 is difficult to observe. Therefore, a receiving plate 11 is provided, which is located on one side of the protective shell 2. An exhaust port 21 is opened on the protective shell 2 at the position corresponding to the fuse section 32, facing the surface of the receiving plate 11. The exhaust port 21 is used to discharge the vaporized fuse section 32 material. The high temperature during a short circuit will cause the fuse section 32 to explode locally, spraying out the material of the fuse section 32. The exhaust port 21 is directly facing the fuse section 32 to ensure that its vaporization products can be sprayed out in a directional manner. The receiving plate 11 serves as an observable collection surface to capture and fix these sprayed gaseous substances. The fixation principle is that the vaporized material sprayed from the fuse section 32 cools down and becomes a solid adhesion layer, transforming the instantaneous vaporization process into a visible physical trace. The presence or absence of the adhesion directly reflects the energy intensity at the moment of fuse breaking, thereby distinguishing between short circuit and overload.

[0047] refer to Figure 1 , 2 As shown in Figure 3, a visual inspection module 12 is provided to visually observe the material of the ejected gaseous fuse portion 32. The visual inspection module 12 includes a camera 121 and a photovoltaic panel 122 fixed on the surface of the receiving plate 11 and connected to the camera 121. The camera 121 is set on the insulator fuse seat 1 and faces the surface of the receiving plate 11. It is used to detect whether there is material covering the fuse portion 32 on the surface of the photovoltaic panel 122. The images or analysis results captured by the camera 121 can be uploaded to the background monitoring system through the communication module. This allows fault diagnosis to be integrated into the smart grid or Internet of Things system, realizing remote real-time monitoring and alarm, which greatly improves the operation and maintenance response. For speed and management efficiency, the surface of a simple receiving board 11 may have uneven reflection and inconsistent color, affecting the accuracy of image analysis. A photovoltaic panel 122 connected to a camera 121 is fixed on the surface of the receiving board 11. Its surface is usually uniform, with small color difference and consistent photoelectric properties. When the vapor of the material of the fuse part 32 adheres to and covers its surface, it will significantly change its local or overall light reflectivity, color and even photoelectric output. The camera 121 can detect this change very sensitively. Therefore, the visual detection module 12 realizes automatic visual detection, eliminates the subjectivity and possible negligence of human judgment, and improves the accuracy of short circuit judgment.

[0048] refer to Figure 1 , 2As shown in Figure 3, according to Joule's law Q=I²Rt, under the same material and the same current, the resistance R is inversely proportional to the cross-sectional area A. The small diameter of the fuse section 32 means that the cross-sectional area A is small, so the resistance R per unit length is greater. Therefore, when the fault current flows, the Joule heat generated per unit volume of the fuse section 32 is much higher than that of the thick connection section 33, resulting in a sharp rise in temperature. This ensures that the melting will occur preferentially and precisely in the fuse section 32, rather than at other random locations. In addition, when the narrow-diameter fuse section 32 vaporizes, the metal vapor is generated from a smaller molten pool, with higher initial pressure and jet speed, making it easier to be effectively discharged through the discharge port 21 and reach the surface of the receiving plate 11.

[0049] refer to Figure 1 , 2 As shown in Figure 3, when the fuse section 32 melts or even vaporizes, the high-temperature molten metal may seep into and flow into the lower-temperature connection section 33. Therefore, the flame-retardant coating applied to the connection can effectively block the spread of molten metal, confining the melting and arc within the area of ​​the fuse section 32, preventing the vaporization of the connection section 33 from affecting the observation of the surface of the receiving plate 11. The flame-retardant coating physically reinforces the connection, making it more resistant to high temperatures. In addition, the flame-retardant coating may generate arc-extinguishing gas or increase the resistance of the arc path at high temperatures, which helps to quickly extinguish the arc after melting and improves the overall safety of the device.

[0050] refer to Figure 1 , 2 As shown in Figure 3, in order to clearly visualize the melting state of the fuse 3 and facilitate maintenance personnel to quickly locate the fuse melting phenomenon, the initial state of the protective shell 2 is set to tilted so that its center of gravity does not pass through the pivot. When the fuse 3 melts and the supporting force disappears, the torque generated by gravity on the protective shell 2 will cause it to automatically rotate and fall in the tilting direction. Compared with horizontal suspension or other balanced states, the tilting design eliminates the uncertainty of rotation. As long as the fuse melts, the gravitational torque will inevitably cause rotation, and the direction of rotation is consistent.

[0051] refer to Figure 1 , 2As shown in Figures 3 and 4, the vaporization of the fuse section 32 is a violent micro-explosion process, which will produce high-speed jets of metal vapor and potentially splashing molten droplets. The width of the discharge port 21 is more than three times the width of the fuse section 32, providing an ample outlet channel for the vapor flow. This avoids the accumulation of pressure in the protective shell 2 due to the narrow outlet, which could potentially damage the shell or affect the jet direction. The wide discharge port 21 can collect the vapor ejected from the fuse section 32 from all directions. In particular, the fuse section 32 may not be perfectly aligned with the center of the discharge port 21, or the vapor jet may have a certain scattering angle. The large magnification ensures that most of the vapor can be guided to the receiving plate 11, reducing ineffective condensation on the inner wall of the protective shell 2 and maximizing the adhesion signal on the receiving plate 11. In the event of a severe short circuit, the amount of vapor generated is huge, while in the event of a minor fault, there may only be a small amount of vapor. A sufficiently wide discharge port 21 can accommodate vapor emissions from trace amounts to large amounts, ensuring that the diagnostic function can work effectively under faults of different energy levels, and that the diagnosis will not be inaccurate due to blockage of the discharge port 21.

[0052] refer to Figure 1 , 2 As shown in Figures 3 and 4, based on the principle of the aforementioned fuse wire 3 protection device, a circuit fault detection method is proposed, which matches the principle of the fuse wire 3 protection device. Firstly, in this circuit fault detection method, the fusing part 32 is made of silver-based material, and the connecting part 33 is made of copper-based material. The fuse wire 3 can be formed by alternately winding and twisting small segments of silver and copper wire. Silver has excellent conductivity, but its melting point is approximately 960°C, which is relatively moderate, and it easily vaporizes after reaching a certain high temperature. Gaseous silver will condense upon cooling. It forms a very fine, gray-black solid particle layer, which is easy to observe and identify. Copper has a melting point of about 1080°C, which is higher than that of silver, and its vapor pressure is relatively low. It is not easy to undergo significant vaporization within the temperature range of the fuse operation. When a fault occurs, the silver-based fuse part 32 will reach its melting point and melt before the copper-based connection part 33. In a short circuit fault with extremely high energy, the silver fuse part 32 will rapidly heat up to the vaporization point and produce a large amount of gaseous silver; while the copper connection part 33 may only be heated to red or slightly melted, but the main vaporization products come from silver.

[0053] Based on this, specific circuit fault detection methods include:

[0054] S1: The installer securely fastens the terminal 31 of the fuse 3 to the wiring terminal 31 of the insulator fuse base 1. During this process, the fuse 3 is straightened and subjected to a certain tension. This tension causes the fuse 3 to support the protective shell 2, so that it overcomes gravity and remains in a relative position with the insulator fuse base 1. The protective shell 2 is thus limited and is in a preset initial working posture.

[0055] S2: When a fault occurs in the protected circuit, such as overload, short circuit, or increased local resistance leading to temperature rise, the fault current flows through fuse 3. According to the Joule heating effect, the temperature of fuse 3 rises. Since the fuse break 32 is a preset weak point, the heat is concentrated here, and the temperature first reaches its melting point, causing the metal at that point to melt. The fuse 3 breaks at the fuse break 32. After the fuse 3 breaks, the tensile force it bears and its supporting effect on the protective shell 2 disappear instantly.

[0056] S3: At the same time as S2 melts, when the cause of the melt is a short circuit, the fault current is extremely large, and energy is injected into the melt section 32 in a very short time. This causes the melt section 32 to not only melt, but its temperature is also rapidly heated to above the boiling point of silver under the action of the electric arc, resulting in violent vaporization. High temperature and high pressure silver vapor is ejected from the molten melt section 32. Since the protective shell 2 has an exhaust port 21 directly opposite the melt section 32, the vapor flow is guided to the preset receiving plate 11.

[0057] S4: High-temperature steam impacts the surface of the lower-temperature receiving board 11, rapidly loses heat, and condenses directly from a gaseous state into solid metal particles, which firmly adhere to the board, forming a layer of gray-black deposit with a metallic luster. At this time, maintenance personnel can visually observe the gray-black deposit layer and determine that the cause of the fuse 3 blowing here is a short circuit.

[0058] When the cause of the fuse failure is overload, the detection method also includes:

[0059] S3-1: When the fault is overload, the current exceeds the rated value but does not reach the short circuit level. Heat continues to accumulate in the fuse 32 and eventually reaches the melting point to melt it. Under the action of the electric arc, the fuse 3 is broken. This process has relatively low energy and mainly heats the metal to a molten state. It may also be accompanied by a very small amount of metal vaporizing due to the high temperature of the electric arc.

[0060] S3-2: Therefore, there is no obvious steam emission. At the same time, since the overload current may last for a period of time, or the circuit design has multiple fuses 32 connected in series to increase heat dissipation and achieve delay characteristics, the overload may cause multiple fuses 32 to melt sequentially or simultaneously. At this time, the maintenance personnel can judge that the cause of the fuse 32 melting is overload based on the absence of solid silver ions on the surface of the receiving board 11 and the fact that all fuses 3 are melted.

[0061] When the cause of the fuse failure is excessive local resistance in the circuit leading to overheating, the detection method also includes:

[0062] S3-3: When the normal operating current passes through, according to Joule's law, the terminal 31 or the vicinity of the terminal 31 will generate continuous heat far exceeding the design value. The heat is highly concentrated in this local area and cannot be dissipated in time, causing the temperature of the terminal 31 to rise continuously until it reaches the melting point of silver. Finally, the terminal 31 is melted or burned near its contact point with the insulator fuse 1.

[0063] S3-4: Since the fuse 3 body is far away from the heat source and has a relatively good heat dissipation path, it may not be completely melted and may only be slightly heated. In this case, the maintenance personnel can determine that the cause of the fuse 3 melting is the problem of increased local resistance.

[0064] The fault detection procedure for the silver-based fuse 3 protection device during reuse is as follows: After correct installation, the device is in its normal state where the fuse 3 is taut and the protective housing 2 is held in a tilted, ready position. When a circuit fault occurs, the fault current causes the fuse 3 to overheat abnormally. Depending on the nature and energy of the fault, the triggering device will present three distinct termination states, thus allowing direct determination of the fault source without the need for instrument measurement. Specifically, if the fault is a severe short circuit, the extremely high current density causes the silver-based fuse part 32 to vaporize violently at the moment of melting, releasing a large amount of silver. Steam is directionally ejected from the exhaust port 21 of the protective shell 2 and condenses, adhering to the opposite receiving plate 11 to form a significant gray-black metallic deposit layer. Simultaneously, the fuse 3 melts, causing the protective shell 2 to lose its support and, under gravity, to rotate noticeably around its axis and fall. If the operator observes the rotation of the protective shell 2 and the coexistence of a dense deposit layer on the receiving plate 11, a short circuit can be diagnosed. If the fault is an overload, a continuous but relatively low overcurrent causes the fuse 32 to accumulate heat to its melting point and melt, but the energy is insufficient to trigger large-scale vaporization. In this case, the protective shell 2 will also rotate. However, the surface of the receiving board 11 is clean, and an inspection of the fuse 3 remnants reveals that multiple fuse sections 32 may have melted, indicating a circuit overload. If the fault originates from excessive contact resistance at the fuse's mounting point, the abnormal heat source is concentrated at the connection between terminal 31 and insulator fuse holder 1. Continuous heat conduction causes localized overheating of terminal 31 until it melts and burns, while the fuse 3 itself, being far from the heat source, may remain slightly molten. This manifests as the protective shell 2 rotating, but the receiving board 11 has no attached material, and the break point of the fuse 3 is located at the root of terminal 31 rather than at the melting point. At point 32, it can be deduced that the cause of the fault is either a temperature rise due to a large local resistance in the line or a temperature rise due to improper installation of terminal 31. In summary, this device converts the invisible current fault energy into three directly observable phenomena: the mechanical position state of the protective shell 2, the visual residual traces on the receiving board 11, and the physical fracture morphology of the fuse 3 remnant. This enables rapid on-site diagnosis of three types of faults: short circuit, overload, and increased local resistance, thereby improving the efficiency of power system maintenance and reducing the probability of secondary faults after reinstalling fuse 3.

[0065] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A silver-based fuse protection device, comprising an insulator fuse holder, characterized in that: The device also includes: A protective shell is rotatably mounted on one side of the insulator fuse holder via a rotating shaft disposed on the insulator fuse holder; A fuse, which penetrates the inner cavity of the protective shell and supports the protective shell, has its terminals extending out of the protective shell and fixed to the insulator fuse holder. Current flows through the insulator fuse holder, through the terminals, and through the fuse to form an electrical path. The fuse includes several fusing parts and several connecting parts, and the fusing parts are connected to the connecting parts. A receiving plate is disposed on one side of the protective shell, and an exhaust port is opened on the protective shell at a position corresponding to the position of the fusible part, facing the surface of the receiving plate. The exhaust port is used to discharge the vaporized fusible part material. Wherein, the melting point of the material of the fuse portion is lower than that of the material of the connecting portion, the terminal is made of the same material as the fuse portion, when the current raises the temperature of the fuse portion to a first temperature, the terminal melts but the fuse portion does not melt, when the current raises the temperature of the fuse portion to a second temperature, both the terminal and the fuse portion melt, when the current raises the temperature of the fuse portion to a third temperature, the material of the fuse portion vaporizes, moves and adheres to the surface of the receiving plate, the first temperature is lower than the second temperature, and the second temperature is lower than the third temperature.

2. The silver-based fuse protection device according to claim 1, characterized in that: The device also includes a vision inspection module, which includes a camera and a photovoltaic panel fixed on the surface of the receiving plate and connected to the camera. The camera is mounted on the insulator fuse holder and faces the surface of the receiving plate, and is used to detect whether the surface of the photovoltaic panel is covered by the material of the fused part.

3. The silver-based fuse protection device according to claim 1, characterized in that: The cross-sectional diameter of the fused portion is smaller than the cross-sectional diameter of the connecting portion.

4. The silver-based fuse protection device according to claim 3, characterized in that: The connection between the fused portion and the connecting portion is coated with a flame-retardant coating.

5. The silver-based fuse protection device according to claim 1, characterized in that: When the fuse supports the protective shell, the protective shell is tilted relative to the vertical direction. When the fuse or the terminal is melted, the protective shell rotates in the tilting direction.

6. The silver-based fuse protection device according to claim 1, characterized in that: The width of the discharge port is greater than the width of the fuse portion, and the ratio of the width of the discharge port to the width of the fuse portion is at least 3 times.

7. A circuit fault detection method, based on the silver-based fuse protection device according to any one of claims 1-6, characterized in that: The detection method includes: S1: Fix the terminal of the fuse to the insulator fuse holder, so that the fuse passes through the protective shell and is taut, limiting the protective shell; S2: When current flows through, the fuse melts, the protective shell loses its limiting force and rotates around the axis; S3: When the fuse breaks, the vapor generated by vaporization passes through the discharge port and adheres to the surface of the receiving plate; S4: The steam condenses and forms a solid. At this time, the operator determines that the fuse blows because of a short circuit based on the solid adhesion area on the surface of the receiving plate.

8. The circuit fault detection method according to claim 7, characterized in that: The detection method may also include: S3-1: When the fuse section melts, it does not generate or generates only a small amount of vaporized steam, and all of the fuse sections melt; S3-2: At this point, the staff determines that the fuse blows because of overload, based on the fact that there is no solid or only a very small amount of solid adhering to the surface of the receiving plate.

9. A circuit fault detection method according to claim 8, characterized in that: The detection method may also include: S3-3: After the fuse blows, the severe ablation point of the fuse is located at the root of the terminal, and there is no significant adhesion layer in the receiving plate area corresponding to the discharge port on the protective shell. S3-4: At this time, the staff determines that the cause of the fuse failure is an increase in local resistance based on the fuse failure status of the terminal.

10. A circuit fault detection method according to claim 7, characterized in that: The fusible part is made of silver-based material, the connecting part is made of copper-based material, and the vapor generated by the silver-based material is gaseous silver.

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