Intelligent excitation fuse

Abstract

The utility model relates to an intelligent excitation fuse (100). The intelligent excitation fuse (100) comprises a partially hollow insulating shell; at least one copper bar (106) in which a plurality of fractures (106A) are laid; a plurality of breaking devices (200); the control circuit board (300) is used for triggering the plurality of on-off devices (200) to carry out on-off actions; the signal fuse wire (301) is connected with at least one copper bar (106) in parallel, and the signal fuse wire (301) is electrically connected with the control circuit board (300) through a signal connecting wire (302), so that when current flowing through the signal fuse wire (301) exceeds preset threshold current, the signal fuse wire (301) is fused and is electrically connected with the control circuit board (300); wherein the control circuit board (300) responds to the fusing of the signal fuse (301) and sends an action signal to the plurality of on-off devices (200) which are connected in series.

Description

Technical Field

[0001] This utility model relates to the field of switchgear technology, and in particular to an intelligent excitation fuse with internal and external triggering functions. Background Technology

[0002] Fuses are commonly used short-circuit current protection devices in AC or DC circuits. Most protection devices in existing DC power systems use fuses, such as those manufactured by Eaton Bussmann, which work on the principle of electrothermal accumulation. When the current passing through the fuse generates sufficient heat, the internal metal conductor melts and arcs, thereby generating an arc voltage that reduces the short-circuit current.

[0003] The aforementioned fuses based on the principle of electrothermal accumulation have the drawback of difficulty in matching thermal fuses with loads in applications such as photovoltaic (PV) systems. A PV system refers to a system where multiple photovoltaic panels are connected in series to form a photovoltaic string, and then multiple photovoltaic strings are connected in parallel to form a photovoltaic array. In this PV array, the current from each photovoltaic string is collected in the PV array connection box, and then connected in parallel to the PV generator connection box. Its output is used directly or processed through inverters. To promptly isolate faulty photovoltaic strings and improve power generation efficiency (when a photovoltaic panel fails to generate electricity, it becomes an energy-consuming load), and to avoid overcurrent hazards caused by incorrect wiring or other reasons during construction and installation, fuses are installed at both ends of each photovoltaic string. Because the short-circuit current of the PV array is greater than the current of a single photovoltaic string, the fuses connected in series with the photovoltaic strings will melt, thus isolating the faulty photovoltaic string. By installing fuses in the array, the photovoltaic array can be protected from current fed back from downstream inverter components (such as discharges from capacitors or capacitors fed back to the photovoltaic array and array wiring) within the rated breaking capacity of the fuses.

[0004] However, in the aforementioned photovoltaic system, since the DC side is formed by multiple photovoltaic panels, the current generated by each panel is very small. Therefore, when a panel fails, the fault current will be only slightly different from the normal current. For example, if the normal operating current is 200 amps, the minimum possible fault current is only 300 amps, about 1.5 times the normal current. Given this situation, it is almost impossible for a fuse, based on its design and manufacturing process, to simultaneously operate normally at 200 amps and trip quickly at 1.5 times the overload current. Therefore, it frequently occurs in photovoltaic systems that fuses fail to trip under low overload currents or malfunction under normal operating currents.

[0005] Furthermore, in the aforementioned photovoltaic protection systems, to achieve higher power generation efficiency, increasingly higher voltage levels and larger protection ranges are being applied. For example, voltage levels are as high as 1500V, and protection ranges range from a few times the rated current to tens of times or even larger.

[0006] Therefore, currently, photovoltaic systems are considering using pyro-fuse, also known as smart fuses, triggered by external control signals. These pyro-fuses can actively disconnect the protected circuit within a specified time under the excitation of an external control signal, completing the disconnection action within milliseconds (ms). Therefore, they have attracted widespread attention in new energy transportation and the semiconductor industry. The aforementioned pyro-fuse works by using the pressure generated by the explosion of a pyrotechnic device, such as gunpowder, to drive the copper busbar cutting mechanism, i.e., the opening plate, until the opening plate breaks the copper busbar, thus achieving rapid disconnection of the fuse.

[0007] However, in practice, it has been found that as voltage levels gradually increase, the single contact of existing smart fuses can no longer meet the insulation withstand voltage requirements. At the same time, if existing smart fuses fail in the event of a fault in the external trigger signal circuit or their own trigger circuit, or if the excitation source fails, the lack of a mechanical means to interrupt the current could lead to serious safety accidents in photovoltaic systems.

[0008] Therefore, there is a technical need in this field to provide an intelligent excitation fuse that can simultaneously solve the above-mentioned shortcomings, has a higher insulation withstand voltage rating, can reliably interrupt short-circuit currents ranging from small to large multiples, and has both internal and external triggering functions. Utility Model Content

[0009] The present invention aims to provide an intelligent excitation fuse that can at least solve some of the above-mentioned problems.

[0010] According to one aspect of the present invention, an intelligent excitation fuse is provided, comprising: a partially hollow insulating shell made of an electrically insulating material; at least one copper busbar sandwiched within the insulating shell, wherein the copper busbar has a plurality of breaks arranged along its length; a plurality of breaking devices disposed within the insulating shell, wherein the plurality of breaking devices are respectively located directly above corresponding breaks; a control circuit board for simultaneously or synchronously triggering the plurality of breaking devices to perform breaking actions, wherein the control circuit board is electrically connected to the plurality of breaking devices to issue an action signal to the plurality of breaking devices connected in series in response to an external trigger signal source; and a signal fuse connected in parallel with the at least one copper busbar, wherein the signal fuse is electrically connected to the control circuit board by means of a signal connection line to melt and disconnect the electrical connection with the control circuit board when the current flowing through the signal fuse exceeds a preset threshold current, wherein the control circuit board issues an action signal to the plurality of breaking devices connected in series in response to the melting of the signal fuse.

[0011] Compared with the prior art, the intelligent excitation fuse according to the present invention has an opening design with multiple opening devices and multiple breaks, and functions such as internal triggering and external triggering. This allows it to meet technical requirements such as fast disconnection, high temperature disconnection reliability, higher insulation withstand voltage level, and reliable disconnection across the entire range of short-circuit currents from small to large multiples required in the photovoltaic industry.

[0012] As a preferred aspect, the insulating housing includes a first housing, a second housing, a third housing, a fourth housing, and a fifth housing stacked from top to bottom, located on the uppermost side. The fourth housing may be a separate component independent of the fifth housing located below it, or it may be a single component integrally formed with the fifth housing located below it.

[0013] In a preferred aspect, the second housing, the third housing, and the fifth housing located at the bottommost side of the insulating housing are form-fitted and form a labyrinth seal.

[0014] As a preferred aspect, the plurality of breaking devices are designed as two breaking devices symmetrically arranged within the fuse, wherein these breaking devices are identical.

[0015] In a preferred aspect, the copper busbar has multiple breaks below each breaking device, and each breaking device has multiple breaking blades, wherein the multiple breaking blades are respectively inserted into the breaks directly below them.

[0016] As a preferred aspect, the fifth housing is provided with an arc-extinguishing chamber containing an arc-extinguishing wire mesh, correspondingly located below each switching device, wherein the plurality of arc-extinguishing chambers are in fluid communication with a chamber containing a signal fuse.

[0017] In a preferred aspect, the signal fuse is designed as a rectangular piece with at least one row of perforations in the middle, wherein pairs of signal connection lines are correspondingly connected to portions located on opposite sides of the row of perforations to transmit a fuse-breaking signal to the control circuit board in response to the melting of the portion with a reduced cross-section near the perforations.

[0018] In a preferred embodiment, the signal fuse and the paired signal connection lines are arranged centrally along the length of the intelligent excitation fuse.

[0019] In a preferred embodiment, the cutting device includes a grid body that is axisymmetric about a vertical axis and a plurality of cutting blades disposed within the grid body, wherein the outer periphery of the grid body is provided with a seal to prevent the inflow of high-pressure gas.

[0020] As a preferred aspect, the signal connection line is designed as a copper sheet with a convex bend or a rounded transition, wherein one end of the copper sheet is connected to the control circuit board and the opposite end is connected to the corresponding part of the signal fuse.

[0021] Other features and advantages of this invention will partly be apparent to those skilled in the art upon reading this application, and partly will be described below in conjunction with the accompanying drawings in the detailed description. Attached Figure Description

[0022] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings, wherein:

[0023] Figure 1 This is a front view of the intelligent excitation fuse according to this utility model;

[0024] Figure 2 It is based on Figure 1 Cross-sectional view of the intelligent excitation fuse in the image;

[0025] Figure 3 It is based on Figure 1 The control circuit diagram for the internal and external triggering of the intelligent excitation fuse in the diagram;

[0026] Figure 4 This is an exploded view of the intelligent excitation fuse according to the present invention, wherein its various components are separated from each other to show more internal details;

[0027] Figure 5 This is another cross-sectional view of the intelligent excitation fuse according to the present invention, wherein the breaking device is in the working state;

[0028] Figure 6 yes Figure 5The side view of the intelligent excitation fuse shown in the figure;

[0029] Figure 7 yes Figure 6 A partially enlarged cross-sectional view of the intelligent excitation fuse taken from the cross section of FF;

[0030] Figure 8 A partially enlarged cross-sectional view of the breaking device applicable to this utility model is shown;

[0031] Figure 9 A partially enlarged cross-sectional view of the components constituting the control circuit applicable to this utility model is shown.

[0032] Explanation of reference numerals in the attached figures:

[0033] 100 - Intelligent excitation fuse; 101 - First housing; 102 - Second housing; 103 - Third housing;

[0034] 104 - Fourth shell; 105 - Fifth shell; 106 - Copper busbar; 106A - Break;

[0035] 107 - Connection path; 200 - Switching device; 201 - Gas generator; 202 - Switching grid;

[0036] 202A - Seal; 202B - Cutting blade; 202C - Grid body; 300 - Control circuit board;

[0037] 301 - Signal fuse; 302 - Signal connector; A1 - Vertical axis; Detailed Implementation

[0038] The schematic scheme of the intelligent excitation fuse disclosed in this utility model is now described in detail with reference to the accompanying drawings. Although the drawings are provided to illustrate some embodiments of this utility model, the drawings are not necessarily drawn to the dimensions of the specific embodiments, and certain features may be enlarged, removed, or partially cut to better illustrate and explain the disclosure of this utility model. Some components in the drawings may be repositioned according to actual needs without affecting the technical effect. The phrase "in the drawings" or similar terms appearing in the specification do not necessarily refer to all drawings or examples.

[0039] Certain directional terms used in the description of the accompanying drawings below, such as “inner,” “outer,” “above,” “below,” and other directional terms, will be understood to have their normal meaning and refer to those directions as normally viewed in the accompanying drawings. Unless otherwise specified, the directional terms used in this specification are generally in accordance with the conventional directions understood by those skilled in the art.

[0040] The terms “first,” “first,” “second,” “second,” and similar terms used in this utility model do not indicate any order, quantity, or importance, but are used to distinguish one component from other components.

[0041] The terms "joining", "connection" and similar terms used in this utility model include both indirect connection of two components with the aid of an intermediate layer such as an adhesive or welding agent or an intermediate component such as a connector or transition piece, and direct connection of two components without the aid of any intermediate layer such as an adhesive or welding agent or an intermediate component such as a connector or transition piece.

[0042] Intelligent excitation fuse

[0043] Figures 1 to 3 The present invention provides an example of an intelligent excitation fuse 100, its breaking device 200, and a control circuit for implementing internal and external triggering. In this example, the intelligent excitation fuse 100 incorporates multiple breaking devices 200 to simultaneously disconnect each phase circuit in a multi-break manner when a fault occurs in the protected circuit, significantly improving the reliability of the intelligent excitation fuse 100. Preferably, the intelligent excitation fuse 100 and its breaking device 200 are suitable for industrial applications, including photovoltaic devices, and therefore, the intelligent excitation fuse 100 must meet the electrical performance and technical requirements of these industrial applications, including response time, breaking current, and arc suppression performance.

[0044] like Figures 1 to 3 As shown, the intelligent excitation fuse 100 may include an insulating housing with a layered structure and, preferably, two, a plurality of breaking devices 200. Specifically, the interior of the insulating housing has mounting cavities for arranging the plurality of breaking devices 200 to allow the breaking devices 200 located therein to move up and down along the vertical axis A1, and the insulating housing may include, for example, a first housing 101, a second housing 102, a third housing 103, a fourth housing 104, and a fifth housing 105, which may be injection molded or molded from an electrically insulating material (e.g., PA66, PPS, etc.) and are stacked from top to bottom, with the uppermost first housing 101, the second housing 102, the third housing 103, the fourth housing 104, and the lowermost fifth housing 105.

[0045] exist Figure 1As shown, the first housing 101, located at the uppermost side, can be a semi-closed cavity structure with a closed upper end and an open lower end. Meanwhile, the second housing 102, located directly below and immediately below it, is designed as a cavity structure with both a partially open upper end and an open lower end. Therefore, the lower end of the first housing 101 can be aligned with the upper end of the second housing 102, allowing the first housing 101 to mate with the cavity of the second housing 102 located directly below it to form a mounting cavity for accommodating the control circuit board 300, which will be described in detail below. Figure 1 The junction of the central portion between the first housing 101 and the second housing 102 shown can be fitted to form an opening through which a signal connection line 302 passes for signal connection to a signal fuse 301 preferably connected in parallel to the copper busbar 106 located in the third housing 103 described below, so that a control circuit for internal and external triggering can be formed between the control circuit board 300 located in the mounting cavity and the signal fuse 301 located in the third housing 103.

[0046] Furthermore, a receiving cavity for accommodating a gas generator 201 is provided above the second housing 102. This gas generator 201 is designed to generate high-pressure gas by receiving trigger signals (internal and / or external trigger signals) from a control circuit including a control circuit board 300, a signal fuse 301, and a signal connection line 302. This high-pressure gas then pushes the switching plate 202 located below it downwards at high speed. As an example, the gas generator 201 has a pair of electrodes that receive trigger signals from the control circuit. The gas generator 201 can be an ignition tube or an MGG gas generator 201. When a current signal is transmitted to the gas generator 201 through the pair of electrodes, the propellant inside the gas generator 201 is ignited, generating a large amount of high-pressure gas that fills the internal cavity of the second housing 102, pushing the switching plate 202 located below the gas generator 201 to move rapidly.

[0047] like Figure 4As clearly shown, to ensure sufficient thrust, the gas generator 201 is preferably fixed within the second housing 102. A mounting base (not shown) may be installed within the second housing 102. The mounting base can be fixed within the second housing 102 in any suitable manner, for example, by a snap-fit ​​structure relative to the second housing 102, an interference fit with the second housing 102, or a bonding agent. The constricted section of the gas generator 201 is shaped to fit within the inner bore of the mounting base, pressing against the bottom of the receiving groove in the second housing 102, restricting the movement of the gas generator 201 relative to the second housing 102, and ensuring sufficient thrust is generated upon gas release. For internal sealing, a sealing element, such as a sealing ring, may be fitted around the outer periphery of the mounting base, pressing the sealing ring between the outer periphery of the mounting base and the inner periphery of the second housing 102. Thus, high-pressure gas will not leak from the top of the second housing 102.

[0048] It should be noted that multiple sets of breaking devices 200 are arranged side-by-side along the length of the second housing 102, preferably two sets of breaking devices 200, wherein these two sets of breaking devices are as follows: Figure 3 The control circuit shown is connected in parallel with the control circuit, which includes the control circuit board 300, the signal fuse 301, and the signal connection line 302. As a result, when an internal trigger and / or external trigger signal is generated in the control circuit, the two side-by-side switching devices 200 are triggered simultaneously or synchronously to perform a switching action on the copper busbar 103 located below them.

[0049] Therefore, since the two sets of breaking devices 200 are symmetrically designed within the fuse 100, this foolproof design effectively reduces the possibility of misassembly or mixing during assembly or assembly by operators or manufacturing robots. At the same time, since the multiple sets of breaking devices 200 are identical, they can be used interchangeably to reduce procurement costs. Furthermore, these breaking devices 200 exhibit excellent synchronization after detonation.

[0050] like Figure 2 and 4 As shown, the copper busbar 106 includes a first copper busbar section, a second copper busbar section, and a signal fuse 301 located on the left side of these figures. As indicated, the first and second copper busbar sections are located on the same straight line, with one end of the first and second copper busbar sections close together to form a gap. Meanwhile, the other ends of the first and second copper busbar sections respectively penetrate through opposite side walls of the third housing 103 to be electrically connected to external phase circuits. Therefore, the signal fuse 301, described in detail below, is positioned at one end of the gap and its two ends are respectively connected to the first and second copper busbar sections, thus forming the aforementioned weak point.

[0051] Preferably, such as Figure 4 As shown, the signal fuse 301 is a rectangular piece with at least one row of perforations in its middle. These perforations can also be rectangular, rhomboid, elliptical, or irregular in shape. The smaller cross-sectional area of ​​the perforations allows for easier and faster melting, leading to the generation of an electric arc. Therefore, the structural dimensions of the perforations in the signal fuse 301 determine the magnitude and duration of the fault current. This allows for the design of specific structural dimensions based on actual needs, ensuring operation according to the expected current-time characteristics. Pairs of signal connection lines 302 passing through the second housing 102 and the third housing 103 are connected to the portions of the signal fuse 301 located on either side of these rows of perforations, thereby enabling control or triggering of the two sets of switching devices 200 based on the on / off state of the signal fuse 301.

[0052] like Figure 4 As shown, multiple copper busbars 103 can be integrally formed by injection molding or molding between the third housing 103 located directly below the second housing 102, and both ends of each copper busbar 106 can extend from the third housing 103 to connect to the respective phase circuit. The portion of the copper busbar 106 located directly below each breaking device 200 may have two breaks 106A, wherein the two breaks 106A are thinner than the other portions of the copper busbar 106, so as to break under the impact of the corresponding breaking blades 202B of the multiple breaking gates 202 described in detail below. As a result, the copper busbar 106 used to form electrical conduction in each phase circuit is cut into two parts at the multiple breaks 106A along its length, thereby breaking the circuit of the corresponding phase. The cutting blade 202B is slidably mounted in the blade groove 201A of the cutting device 200 described in detail below and located above the corresponding copper busbar 106, so that when the cutting blade 202B is forced to move, it impacts the fracture surface 106A by means of the kinetic energy of the high-pressure gas and its own gravitational potential energy.

[0053] Preferably, such as Figure 8As shown, the copper busbar 106 may have guide holes on its multiple fracture surfaces 106A that are thinned near the fracture surfaces 106A along the thickness direction. Correspondingly, a portion of the end face (lower end face) of the cutting blade 202B adjacent to the multiple fracture surfaces 106A, such as the tip of the blade extending downward toward the fracture surface 106A, forms a guide section. The dimension of the guide section in the transverse direction of its extension direction, i.e., the transverse dimension, can be smaller than that of the grid plate. Thus, when the multiple cutting blades 202B are forced to move toward the multiple copper busbars 106, the tips of each cutting blade 202B pass through the corresponding guide holes with matching shapes first. This allows the multiple cutting blades 202B that are not in the desired same orientation due to mechanical errors, installation errors, or uneven forces, such as some cutting blades 202B being tilted relative to other cutting blades 202B, to be corrected to the desired same vertical state because their respective guide sections pass through the corresponding guide holes. As a result, the corresponding cutting blades 202B adjacent to each guide section can act synchronously on the corresponding multiple fracture surfaces 106A, so that the multiple cutting blades 202B can cut the corresponding fracture surfaces 106A simultaneously or synchronously.

[0054] Optionally, the plurality of breaking blades 202B and the guide sections extending therefrom can be designed as rectangular sheets. Exemplarily, the thickness of the breaking blades 202B and the width of the plurality of fracture surfaces 106A can be 2 mm to 5 mm, and the thickness of the copper busbar 106 at the plurality of fracture surfaces 106A is preferably, for example, 0.5 mm to 1 mm. Preferably, in addition to forming grooves with the same shape as the fracture surfaces 106A on the surface of the copper busbar 106, V-grooves or other conceivable shapes can also be formed on the surface of the copper busbar 106 in the area corresponding to the fracture surfaces 106A to facilitate the intended breaking of the fracture surfaces 106A.

[0055] It can be seen that since the copper busbar 106 has multiple breaks 106A below each switching device 200, the electrical clearance and creepage distance of the copper busbar 106 at the multiple breaks 106A are doubled, and the corresponding insulation voltage is higher, thus meeting the requirements of higher voltage levels.

[0056] Optionally, the third housing 103 in the intelligent excitation fuse 100 may also have an anti-rotation portion 103A extending upward into the inner side of the second housing 102. Here, the anti-rotation portion 103A can be located on both sides of the breaking device 200 within the second housing 102 and subsequently engage with the anti-rotation groove in the breaking grid 202, which is shaped to match the anti-rotation groove described in detail below. This design facilitates the positioning and installation of the second housing 102, the copper busbar 106, and the third housing 103. On the other hand, the guiding engagement between the anti-rotation portion 103A and the anti-rotation groove of the breaking grid 202 ensures that the breaking grid 202 is guided during the downward movement driven by high-pressure gas, thereby preventing the breaking grid 202 from undergoing undesirable rotation, which would degrade the breaking effect of the breaking blade 202B.

[0057] like Figure 2 and 4 As shown, the second housing 102, the copper busbar 106 and the third housing 103 are shaped to form a labyrinth-like sealing structure to minimize the leakage of gas injected by the gas generator 201, thereby ensuring the pushing effect on the multiple cutting blades 202B.

[0058] like Figure 2 As shown in Figure 4, a fourth housing 104, which is open at both the upper and lower ends, and a fifth housing 105, which is open at the upper end and closed at the lower end, are arranged sequentially below the third housing 103 as optional components. The fourth housing 104 and the fifth housing 105 located below it can both be provided as separate components (e.g., Figure 2 (As shown), it can also be integrally formed with the fifth housing 105 located below it as a one-piece structure by injection molding or molding (as shown). Figure 4 (As shown). For the former, a labyrinth-like seal structure is preferably formed between the fourth housing 104 and the fifth housing 105 to minimize leakage of the gas injected by the gas generator 201, thereby ensuring the pushing effect on the multiple cutting blades 202B (as shown). Figure 2 (As shown). For the latter, a labyrinth-like seal structure needs to be formed between the third housing 103 and the fifth housing 105 to minimize leakage of the gas injected by the gas generator 201, thereby ensuring the pushing effect on the multiple cutting blades 202B (as shown). Figure 4 (As shown).

[0059] Optionally, to improve safety performance by quickly and safely extinguishing the arc when the break 106A of the copper busbar 106 is disconnected by multiple cutting blades 202B, such as... Figure 2 and 4 As shown, the fifth housing 105 has two arc-extinguishing chambers with their bottoms covered by arc-extinguishing wire mesh 203. The arc-extinguishing wire mesh 203 is fixed to the inner wall of the two arc-extinguishing chambers of the fifth housing 105 to reduce the arc temperature.

[0060] Alternatively, such as preferably in Figure 5 As shown, an intermediate chamber corresponding to the signal fuse 301 is added inside the fifth housing 105. This intermediate chamber is fluidly connected to the two arc-extinguishing chambers containing the arc-extinguishing wire mesh 203 via a connection passage 107 as indicated by the arrow. As a result, even if a large amount of arc and gas is formed in the arc-extinguishing chamber, it can be transferred to the intermediate chamber located in the middle via the connection passage, thereby effectively reducing the gas pressure in the arc-extinguishing chamber and the risk of arc-extinguishing chamber rupture, ultimately improving the arc-extinguishing capability of the fuse 100.

[0061] control circuit

[0062] like Figure 3 As shown, this diagram illustrates a control circuit including a control circuit board 300, a signal fuse 301, and a signal connection line 302. The control circuit board 300 is signal-connected to an external trigger signal source, which may be determined by an external control system located at the user end, based on external control conditions. These external control conditions may include sending a trigger signal under specific conditions at zero current, or setting a threshold value. When a monitored indicator, such as a short-circuit current value, exceeds this threshold, the external trigger signal source is activated, providing a trigger signal to the control circuit board 300. This triggers the control circuit board 300 to send an action signal to the series-connected switching devices 200. As a result, the control circuit board 300, in response to the signal from the external trigger signal source, simultaneously triggers multiple side-by-side switching devices 200 to cut multiple breaks 106A located at different positions in the copper busbar 106.

[0063] Meanwhile, the signal fuse 301 is preferably connected in parallel with a plurality of switching devices 200, and as... Figure 3 The circuit board 301 is connected in series with the control circuit board 300 via signal connection line 302. Therefore, in response to the current flowing through the signal fuse 301 exceeding a set limit current, the heat generated by the current gradually accumulates on the signal fuse 301, causing it to melt first at the row of through-holes. As a result, the series connection between the melted signal fuse 301 and the control circuit board 300 via signal connection line 302 is broken. The control circuit board 300, in response to this disconnection signal (which serves as an internal trigger signal), simultaneously triggers multiple parallel-arranged switching devices 200 to cut multiple breaks 106A located at different positions in the copper busbar 106.

[0064] Opening grid plate

[0065] like Figure 2 and 4 As best shown in Figure 8, the breaking grid 202 may include, for example, a grid body 202C that is axisymmetric about the vertical axis A1, formed by injection molding or molding of an electrically insulating material (e.g., PA66, PPS, etc.), and preferably two breaking blades 202B disposed therein. Those skilled in the art will understand that, for a two-phase excitation fuse, the breaking grid 202 may include two copper busbars 106 and two opposing breaking blades 202B, while for a three-phase excitation fuse, the breaking grid 202 may include three copper busbars 106 and three opposing breaking blades 202B. Exemplarily, the copper busbars 106 may be straight plates, and the plurality of copper busbars 106 may be perpendicular to the transverse plane. Figure 8The figures are arranged at intervals on the plane of the page where they are located. Correspondingly, multiple cutting blades 202B can be positioned one-to-one with multiple copper busbars 106 within the grid body 202C.

[0066] like Figures 4 to 5 As best shown, the breaking blade 202B comprises two blades arranged side by side; the breaking blade 202B extends from the body 201 of the breaking grid 202 toward the corresponding break 106 in the copper busbar 106. Figure 5 As shown, before the gas generator is triggered by an external signal, the end of the breaking blade 202B in the breaking grid 202 is located inside the corresponding fracture 106A. Specifically, as... Figure 8 As shown in detail, each of the interrupting grid plates 202 is equipped with its own dedicated receiving cavity, and a seal 202A is provided on the outer periphery of the grid plate body 202C of the interrupting grid plate 202 to prevent the inflow of high-pressure gas. As a result, although multiple interrupting grid plates 200 are arranged side by side, when they are triggered simultaneously or synchronously by the gas generator 201, the high-pressure gas they experience will not cross-flow, thus affecting the operation of their respective interrupting grid plates 202. That is, due to this independent sealing design, inconsistent operation of the interrupting grid plates 202 caused by pressure relief or cross-flow of high-pressure gas can be effectively avoided.

[0067] like Figure 8 As shown, preferably, the end of the cutting blade 202B has a V-shaped structure. Correspondingly, a downward-opening stress concentration groove is provided at the centerline of the lower surface of the fracture 106A, wherein the stress concentration groove is positioned opposite to the tip of the cutting blade 202B of the cutting grid 202. Through the cooperation between the tip of the cutting blade 202B and the stress concentration groove, stress concentration is easily generated at the centerline of the copper busbar 106, making it easier for the cutting blade 202B of the cutting grid 202 to cut the copper busbar 106 from the middle position.

[0068] Preferably, such as Figure 8 As shown, the main body 202C of the grid plate also has an anti-rotation groove that extends vertically, and its design is as follows: Figure 1 The anti-rotation portion extending upward from the third housing 103 forms a shape fit, thereby ensuring that the grid body 202C is guided during the downward movement driven by high-pressure gas, thus preventing the grid body 202C from undergoing undesirable rotation, which would degrade the breaking effect of the cutting blade 202B.

[0069] It should also be pointed out that, despite Figures 4 to 5Figure 8 shows a breaking grid 202 with paired breaking blades 202B for performing a breaking operation on a break with a break point 106A (which may be referred to as a double-blade direct-opening type). Alternatively, it is also feasible to design a breaking grid 202 with multiple blades having two or more insulating blades (which may be referred to as a multi-blade direct-opening type), and these variations are all covered within the scope of protection intended for this application.

[0070] Signal fuse

[0071] like Figure 4 and 9 As best illustrated, the signal fuse 301 is preferably designed as a rectangular silver sheet, and is arranged on the upper side of the copper busbar 106 in parallel with it. To avoid damage to the signal fuse 301 caused by installation torque and torsion of the copper busbar 106 due to poor mounting flatness, the signal fuse 301 is preferably arranged between two parallel switching devices 200. Correspondingly, pairs of signal connection lines 302 passing through the second housing 102 are symmetrically arranged and connected to the two sides of the signal fuse 301 symmetrically arranged with respect to the rows of perforations. As a result, the pairs of signal connection lines 302 achieve electrical or signal conduction based on the reduced cross-section connection portion near the perforations of the signal fuse 301.

[0072] With this design, the current flowing through the copper busbar 106 is monitored by the signal fuse 301. When the current flowing through the signal fuse 301 exceeds the set limit current, heat gradually accumulates, causing the signal fuse 301 to melt. This melting signal is transmitted to the control circuit board 300 via the signal connection line 302. Subsequently, the control circuit board 300 generates a disconnection signal in response to the melting signal of the signal fuse 301 and transmits the disconnection signal to at least two disconnection devices 200 arranged side by side, thereby cutting off the connection between the multiple breaks 106A arranged along the length of the copper busbar 106, which is the so-called internal trigger operation.

[0073] Related to the material used to manufacture the signal fuse 301 and the design of its rows of perforations, a threshold current or limiting current that causes the signal fuse 301 to blow can be set within a desired range. For example, this threshold current or limiting current could be the minimum possible fault current, which is only about 1.5 times the normal current. Such a design is particularly desirable for the photovoltaic industry.

[0074] signal connection cable

[0075] exist Figure 4 , 7Figure 9 shows a feasible embodiment of the signal connection line 302 according to the present invention. Here, the signal connection line 302 is designed as, for example, a copper sheet with a convex bend or arc transition in the middle section, wherein one end of the copper sheet is connected, for example, by insertion to a control circuit board 300 located above it and sandwiched in a cavity between the first housing 101 and the second housing 102, and the other end is laid to the corresponding part of the signal fuse 301 by forming a bend or fold.

[0076] Therefore, compared with the existing technology of directly using electrical wires for connection, designing the signal connection line 302 as a copper sheet helps to achieve better durability and operational reliability in the high-temperature environment that often occurs inside the fuse 100. Furthermore, by providing a convex bend or arc transition in the middle section of the signal connection line 302, the flexibility of the copper sheet itself can be increased, which helps to avoid solder joint pulling defects caused by welding or other assembly errors.

[0077] Working principle of intelligent excitation fuse

[0078] Under normal operating conditions, current flows through the first copper busbar section, the second copper busbar section of the copper busbar 106, and the signal fuse 301 connected in parallel with it.

[0079] In applications such as those in the photovoltaic industry, when a fault current of only a small multiple (e.g., 1.5 times) of the normal current occurs, the signal fuse 301 blows. The signal of the blown signal fuse 301, which serves as an internal trigger signal, is transmitted via signal connection line 302 to the control circuit board 300. The control circuit board 300 then generates a disconnection signal in response to the blown signal of the signal fuse 301 and transmits the disconnection signal to at least two side-by-side disconnecting devices 200, thereby severing the connection between multiple breaks 106A arranged along the length of the copper busbar 106—a so-called internal trigger operation.

[0080] Meanwhile, independent of the aforementioned internal triggering operation, the control circuit board 300 is signal-connected to an external trigger signal source. This external trigger signal source can be determined by external control conditions, i.e., by a control system located at the user end. The external control conditions could be sending a trigger signal under specific conditions at zero current, or setting a threshold value. When a monitored indicator, such as a short-circuit current value, exceeds this threshold, the external trigger signal source is activated, providing a trigger signal to the control circuit board 300 to trigger an action signal to the electrically connected, series-connected switching devices 200. As a result, the control circuit board 300, in response to the signal from the external trigger signal source, simultaneously triggers multiple side-by-side switching devices 200 to cut multiple breaks 106A located at different positions in the copper busbar 106.

[0081] As can be seen from the above, the intelligent excitation fuse 100 of this utility model has a breaking design with multiple breaking devices 200 and multiple breaks 106A, and functions such as internal triggering and external triggering. This allows it to meet technical requirements such as fast disconnection, high temperature disconnection reliability, higher insulation withstand voltage level, and reliable disconnection across the entire range of short-circuit currents from small to large multiples required in the photovoltaic industry.

[0082] It should be understood that although this specification describes various embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0083] The above description is merely an illustrative embodiment of this utility model and is not intended to limit the scope of this utility model. Any equivalent changes, modifications, and combinations made by those skilled in the art without departing from the concept and principles of this utility model should fall within the protection scope of this utility model.

Claims

1. An intelligent excitation fuse (100), characterized in that, include: A partially hollow insulating shell made of electrically insulating material; At least one copper busbar (106) is sandwiched within the insulating housing, wherein the copper busbar (106) is provided with a plurality of breaks (106A) along its length. Multiple breaking devices (200) are provided inside the insulating housing, wherein the multiple breaking devices (200) are located directly above the corresponding break (106A); A control circuit board (300) for simultaneously or synchronously triggering the plurality of switching devices (200) to perform switching actions, wherein the control circuit board (300) is electrically connected to the plurality of switching devices (200) to respond to an external trigger signal source sending an action signal to the plurality of switching devices (200) connected in series; and A signal fuse (301) is connected in parallel with at least one copper busbar (106), wherein the signal fuse (301) is electrically connected to the control circuit board (300) by means of a signal connection line (302) to blow and disconnect the electrical connection with the control circuit board (300) when the current flowing through the signal fuse (301) exceeds a preset threshold current, wherein the control circuit board (300) sends an action signal to a plurality of disconnecting devices (200) connected in series in response to the blowing of the signal fuse (301).

2. The intelligent excitation fuse (100) as described in claim 1, characterized in that, The insulating housing includes a first housing (101), a second housing (102), a third housing (103), a fourth housing (104), and a fifth housing (105) stacked from top to bottom. The fourth housing (104) may be a separate component independent of the fifth housing (105) below it, or it may be a single component integrally formed with the fifth housing (105) below it.

3. The intelligent excitation fuse (100) as described in claim 1, characterized in that, The second housing (102), the third housing (103), and the fifth housing (105) located at the bottom are form-fitted and form a labyrinth seal.

4. The intelligent excitation fuse (100) as described in claim 1, characterized in that, The plurality of breaking devices (200) are designed as two breaking devices (200) symmetrically arranged within the fuse (100), wherein these breaking devices (200) are identical.

5. The intelligent excitation fuse (100) as described in claim 4, characterized in that, The copper busbar has multiple breaks (106A) below each breaking device (200), and each breaking device (200) has multiple breaking blades (202B), wherein the multiple breaking blades (202B) are respectively inserted into the breaks (106A) directly below them.

6. The intelligent excitation fuse (100) as described in claim 2, characterized in that, The fifth housing contains an arc-extinguishing chamber with an arc-extinguishing wire mesh (203) located below each switching device (200), wherein the arc-extinguishing chambers are in fluid communication with the chamber containing the signal fuse (301).

7. The intelligent excitation fuse (100) as described in claim 1, characterized in that, The signal fuse (301) is designed as a rectangular piece with at least one row of perforations in the middle, wherein pairs of signal connection lines (302) are correspondingly connected to portions located on opposite sides of the row of perforations to transmit a fuse-breaking signal to the control circuit board (300) in response to the melting of the portion with a reduced cross-section near the perforations.

8. The intelligent excitation fuse (100) as described in claim 7, characterized in that, The signal fuse (301) and the paired signal connection lines (302) are arranged centrally along the length of the intelligent excitation fuse (100).

9. The intelligent excitation fuse (100) as described in claim 1, characterized in that, The cutting device (200) includes a grid body (202C) that is axially symmetric about a vertical axis and a plurality of cutting blades (202B) arranged in the grid body (202C), wherein the outer periphery of the grid body (202C) is provided with a seal (202A) to prevent high-pressure gas from flowing in.

10. The intelligent excitation fuse (100) as described in claim 1, characterized in that, The signal connection line (302) is designed as a copper sheet with a convex bend or a rounded transition, wherein one end of the copper sheet is connected to the control circuit board (300) and the other end is connected to the corresponding part of the signal fuse (301).

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