A short-circuit protection device for a power generation system

Abstract

This application provides a short-circuit protection device for a power generation system, relating to the field of low-voltage electrical appliances. It includes a frame containing a cavity through which the power supply arc passes; and a first arc-extinguishing grid, spaced apart within the cavity of the frame, forming a channel with the same path as the cavity. This application achieves progressive energy dissipation of the arc by setting up an alternately distributed three-stage arc-extinguishing grid system and a composite path control structure: the third arc-extinguishing grid and the front form a dense cutting layer to force initial arc splitting; the inclined connecting middle section and the second arc-extinguishing grid construct a twisted and elongated channel; the reverse bending section constructs a three-dimensional cable network to rapidly increase the arc resistance; the grooved and protruding sections guide the arc to bifurcate and ascend, ultimately forcing the arc to zero through the synergistic effect of multi-stage segmentation, path reconstruction, and heat dissipation area.

Description

Technical Field

[0001] This utility model relates to the field of low-voltage electrical appliances, and more specifically, to a short-circuit protection device for a power generation system. Background Technology

[0002] In the field of low-voltage electrical appliances, short-circuit protection devices, as key safety components of power systems, have always focused on rapid response and reliable disconnection in their technological development. Traditional circuit breakers achieve short-circuit protection through electromagnetic trip units or overcurrent trip units. When the line current exceeds a set threshold, the trip unit drives the contacts to quickly separate to interrupt the fault current. Such devices are widely used in low-voltage distribution networks. For example, the DW15 series frame circuit breaker, through its inverse-time overload protection and instantaneous short-circuit protection characteristics, forms a two-stage or three-stage protection curve, playing an important role in low-voltage power supply systems for industrial and civil buildings. However, as the capacity of distribution networks increases to 200kVA and above, the terminal short-circuit current can reach 70kA or even higher, placing stringent requirements on the breaking capacity of protection devices. Although existing technologies employ a combination of fuses and knife switches, utilizing the high breaking capacity of fuses to handle high-current faults, significant technical bottlenecks still exist in the arc-extinguishing stage.

[0003] Existing short-circuit protection devices face the core problem of rapid arc extinguishing during the arc extinction process. The arc generated when circuit breaker contacts separate needs to be extinguished through arc blowing, arc pulling, or the cold wall effect. However, in high-current scenarios, the arc energy increases dramatically, and traditional arc-extinguishing chamber designs cannot meet the rapid cooling requirements. Experimental data shows that although increasing the resistance can accelerate extinguishing when the arc current decreases, the arc will continue to burn if there is a stable intersection point between the load line and the arc's volt-ampere characteristic curve.

[0004] Therefore, we have made improvements to this and proposed a short-circuit protection device for power generation systems. Utility Model Content

[0005] In order to achieve the above-mentioned objectives, this utility model provides a short-circuit protection device for a power generation system to improve the aforementioned problems.

[0006] The application is as follows:

[0007] include:

[0008] The frame contains a cavity through which the power supply arc passes;

[0009] The first arc-extinguishing grid, spaced apart within the cavity of the frame, forms a channel with the same penetration path as the cavity, and has the following characteristics:

[0010] The bending portion is provided on the first arc-extinguishing grid and forms a bending path in the vertical direction that is close to or far away from the adjacent first arc-extinguishing grid;

[0011] The second arc-extinguishing grid is alternated with the first arc-extinguishing grid, and a single second arc-extinguishing grid is located between two adjacent first arc-extinguishing grids, with a length of at most half that of the first arc-extinguishing grid;

[0012] The third arc-extinguishing grid is interposed between the first and second arc-extinguishing grids, and its length is at most half that of the second arc-extinguishing grid.

[0013] Preferably, the first arc-quenching grid further includes:

[0014] The front part is located near the third arc-extinguishing grid and has the same length as the third arc-extinguishing grid.

[0015] Preferably, the first arc-quenching grid further includes:

[0016] In the middle part, the first arc-extinguishing grid is located near the second arc-extinguishing grid and has the same length as the second arc-extinguishing grid. It is connected to the front part by a slope, and the second arc-extinguishing grid extends with the same slope.

[0017] Preferably, the middle part and the bent part are connected by a beveled surface that is the same as that of the front part and the middle part.

[0018] Preferably, the bending direction of the bent portion is opposite to that of the adjacent bent portion.

[0019] Preferred options also include:

[0020] A groove portion is provided on a single first arc-extinguishing grid, forming a V-shaped cavity;

[0021] A protrusion is provided on a single first arc-extinguishing grid, forming a V-shaped plate that covers the groove on the projection surface.

[0022] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0023] In the scheme of this application:

[0024] To address the issues of incomplete arc segmentation, limited path elongation, and insufficient heat dissipation efficiency in existing arc-extinguishing grids, this application achieves progressive energy dissipation of the arc by setting up an alternating three-level arc-extinguishing grid system and a composite path control structure: the third arc-extinguishing grid and the front form a dense cutting layer to force initial arc segmentation; the inclined connecting middle section and the second arc-extinguishing grid construct a twisted and elongated channel; the reverse bending section constructs a three-dimensional twisted cable network to rapidly increase the arc resistance; the groove and protrusion sections guide the arc to bifurcate and climb, and finally, through the synergistic effect of multi-level segmentation, path reconstruction, and heat dissipation area, the arc is forced to zero. Attached Figure Description

[0025] Figure 1 A front view of a short-circuit protection device for a power generation system provided in this application;

[0026] Figure 2 A cross-sectional view of a short-circuit protection device for a power generation system provided in this application;

[0027] Figure 3 A cross-sectional view of a short-circuit protection device for a power generation system provided in this application.

[0028] The image shows:

[0029] 1. Frame; 2. First arc-extinguishing grid; 21. Front part; 22. Middle part; 23. Bending part; 24. Groove part; 25. Protrusion part; 3. Second arc-extinguishing grid; 4. Third arc-extinguishing grid. Detailed Implementation

[0030] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0031] For an example, please refer to... Figure 1 , Figure 2 and Figure 3 A short-circuit protection device for a power generation system, comprising:

[0032] Frame 1 contains a cavity through which the power supply arc passes;

[0033] The first arc-extinguishing grid 2 is spaced apart within the cavity of the frame 1, forming a channel with the same penetration path as the cavity, and has the following characteristics:

[0034] The bending portion 23 is provided on the first arc-extinguishing grid 2 and forms a bending path in the vertical direction that is close to or far away from the adjacent first arc-extinguishing grid 2;

[0035] The second arc-extinguishing grid 3 is alternately arranged with the first arc-extinguishing grid 2, and a single second arc-extinguishing grid 3 is located between two adjacent first arc-extinguishing grids 2, with a length of at most half that of the first arc-extinguishing grid 2;

[0036] The third arc-extinguishing grid 4 is interposed between the first arc-extinguishing grid 2 and the second arc-extinguishing grid 3, and its length is at most half that of the second arc-extinguishing grid 3;

[0037] When a short-circuit fault occurs, the electric arc is driven into the channel of the cavity of frame 1 by electromagnetic force or air blowing. At this time, the third arc-extinguishing grid 4, as the foremost group of short grid plates, is the first to contact the electric arc. Because its length is extremely short, not more than half that of the second arc-extinguishing grid 3, and it is densely distributed, it forms multiple "cutting points" on the initial path of the electric arc, forcing the electric arc to split into multiple short arc segments in advance. At the same time, the front part 21 of the first arc-extinguishing grid 2 is of the same length as the third arc-extinguishing grid 4 and is arranged adjacent to it, further reinforcing the segmentation strength of the entrance area and significantly improving the arc voltage drop in the initial stage;

[0038] The arc continues to migrate deeper into the channel, entering the cooperative region formed by the middle 22 of the second arc-extinguishing grid 3 and the first arc-extinguishing grid 2. The second arc-extinguishing grid 3 makes it a "stepped springboard" interspersed between the long grid plates. The arc needs to repeatedly cross the gaps between adjacent first arc-extinguishing grids 2 and is forced to turn at the inclined joint of the middle 22, which increases the combustion path of the arc;

[0039] When the electric arc advances to the bend 23 of the first arc-extinguishing grid 2, the bend 23 reconstructs the arc path through abrupt deformation in the vertical direction: the arc is forcibly squeezed or lifted, forming a sharp turn or even a loop; the mechanical constraint at the bend greatly increases the contact area between the arc and the metal grid, accelerating plasma cooling; the abrupt path change hinders the movement of ions inside the arc, causing the resistance to increase dramatically and exceed the system sustaining voltage.

[0040] At this point, the previously segmented short arc segments are superimposed in series in the bending area, forming a total arc voltage drop far exceeding the power supply voltage, which ultimately blocks the current path and achieves forced zeroing. Furthermore, the heat generated by the arc on the arc-extinguishing grid can increase the heat dissipation area through the additional area generated by the bending.

[0041] The first arc-extinguishing grid 2 also includes:

[0042] The front part 21 is located near the third arc-extinguishing grid 4 of the first arc-extinguishing grid 2 and has the same length as the third arc-extinguishing grid 4;

[0043] The third arc-extinguishing grid 4 and the front part 21 together form the entrance interception layer. The dense distribution of the short grid plate group instantly cuts the electric arc into multiple short arc segments. The equal length design of the front part 21 and the third arc-extinguishing grid 4 ensures that the segmentation intensity is uniformly transmitted, forcing the electric arc to bear a high voltage drop in the initial stage.

[0044] The first arc-extinguishing grid 2 also includes:

[0045] The middle part 22 is located near the second arc-extinguishing grid 3 of the first arc-extinguishing grid 2 and has the same length as the second arc-extinguishing grid 3. It is connected to the front part 21 by a slope, and the second arc-extinguishing grid 3 has the same slope extension.

[0046] The inclined connecting structure plays a core guiding role: the inclined surfaces of the front part 21 and the middle part 22 guide the arc to turn into the stepped area, while the synchronous inclined surface of the second arc extinguishing grid 3 extends to form a continuous deflection channel. This inclined surface seamlessly guides the arc from the stretching area of ​​the middle part 22 to the bending area, avoiding abrupt changes in the path that could cause the arc to escape. The path is forcibly twisted and lengthened, and the heat dissipation area continuously increases as the inclined surface extends.

[0047] A beveled surface, identical to that of the front part 21 and the middle part 22, is provided between the middle part 22 and the bent part 23.

[0048] The bending direction of the bent portion 23 is opposite to that of the adjacent bent portion 23.

[0049] Also includes:

[0050] The groove portion 24 is provided on a single first arc-extinguishing grid 2, forming a V-shaped cavity;

[0051] The protrusion 25 is provided on the single first arc-extinguishing grid 2 and forms a V-shaped plate that covers the groove 24 on the projection surface;

[0052] The V-shaped grooves and protrusions on the same grid plate constitute a self-matching arc extinguishing unit: when the arc migrates to this point, the V-shaped cavity guides the arc to bifurcate into two bypass paths, and the protrusion 25 acts as a forced shunt to increase the arc creepage distance, locally lengthen the arc and enhance metal heat dissipation.

[0053] The technical scope of this utility model is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this utility model, and all such modifications and variations should fall within the protection scope of this utility model.

Claims

1. A short-circuit protection device for a power generation system, characterized by comprising: include: The frame (1) contains a cavity through which the power supply arc passes; The first arc-extinguishing grid (2) is spaced apart in the cavity of the frame (1) to form a channel with the same penetration path as the cavity, and has the following characteristics: The bending portion (23) is provided on the first arc-extinguishing grid (2) and forms a bending path in the vertical direction close to or far away from the adjacent first arc-extinguishing grid (2); The second arc-extinguishing grid (3) is alternately arranged with the first arc-extinguishing grid (2), and a single second arc-extinguishing grid (3) is located between two adjacent first arc-extinguishing grids (2), with a length of at most half that of the first arc-extinguishing grid (2); The third arc-extinguishing grid (4) is interspersed between the first arc-extinguishing grid (2) and the second arc-extinguishing grid (3), and its length is at most half that of the second arc-extinguishing grid (3).

2. A short-circuit protection device for a power generation system according to claim 1, characterized by The first arc-quenching grid (2) further includes: The front part (21) is located near the third arc-extinguishing grid (4) of the first arc-extinguishing grid (2) and has the same length as the third arc-extinguishing grid (4).

3. A short-circuit protection device for a power generation system according to claim 2, characterized by The first arc-quenching grid (2) further includes: The middle part (22) is located near the second arc-extinguishing grid (3) of the first arc-extinguishing grid (2) and has the same length as the second arc-extinguishing grid (3). It is connected to the front part (21) by a slope, and the second arc-extinguishing grid (3) has the same slope extension.

4. A short-circuit protection device for a power generation system according to claim 3, characterized in that, The middle part (22) and the bent part (23) are connected by the same inclined surface as the front part (21) and the middle part (22).

5. A short-circuit protection device for a power generation system according to claim 4, characterized in that, The bending direction of the bent portion (23) is opposite to that of the adjacent bent portion (23).

6. A short-circuit protection device for a power generation system according to claim 5, characterized in that, Also includes: A groove (24) is provided on a single first arc-extinguishing grid (2) to form a V-shaped cavity; A protrusion (25) is provided on a single first arc-extinguishing grid (2) and forms a V-shaped plate that covers the groove (24) on the projection surface.

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