Direct-current arc coupling device, detection device and component-level product

Abstract

The invention discloses a direct-current arc coupling device, a detection device and a component-level product. The direct-current arc coupling device comprises a coupling coil, the distance between the coupling coil and a main loop is smaller than a first preset distance, and the distance between the circle center of the coupling coil and the circle center of a hollow structure of the main loop is smaller than a second preset distance; and the coupling coil is used for coupling a direct-current arc generated in the main loop. According to the invention, the application range of direct current arc detection is expanded, and the accuracy of direct current arc detection is improved.

Description

Technical Field

[0001] This invention relates to the field of safety monitoring technology for photovoltaic power generation systems, and in particular to a DC arc coupling device, a detection device, and a component-level product. Background Technology

[0002] With the widespread application of photovoltaic systems, arc faults in DC lines have become a significant safety hazard. The requirements for arc detection have gradually evolved from string-level detection to module-level arc detection, and even arc fault location. While existing technologies employ various arc signal coupling methods, they cannot be applied to arc detection in module-level products. Summary of the Invention

[0003] This invention provides a DC arc coupling device, a detection device, and a component-level product to expand the application scope of DC arc detection and improve the accuracy of DC arc detection.

[0004] According to one aspect of the present invention, a DC arc coupling device is provided, comprising: a coupling coil, wherein the distance between the coupling coil and the main circuit is less than a first preset distance, and the distance between the center of the coupling coil and the center of the hollow structure of the main circuit is less than a second preset distance; the coupling coil is used to couple a DC arc generated in the main circuit.

[0005] Optionally, the coupling coil is attached to the main circuit.

[0006] Optionally, the coupling coil and the hollow structure of the main circuit are arranged in concentric circles.

[0007] Optionally, both the coupling coil and the main circuit are mounted on a circuit board;

[0008] The coupling coil and the main circuit are located in different wiring layers of the circuit board, and the wiring layer where the coupling coil is located is adjacent to the wiring layer where the main circuit is located.

[0009] Optionally, one layer of the coupling coil includes at least two turns of coil arranged in concentric circles.

[0010] Optionally, the coupling coil has at least two layers, and the at least two layers of coupling coil are arranged in concentric circles; the coupling coils of different layers are located in different wiring layers and are electrically connected through vias.

[0011] Optionally, the main circuit has at least two layers; the main circuits of different layers are located in different wiring layers and are electrically connected through vias.

[0012] Optionally, the coupling coil is sleeved on the outer edge of the main circuit.

[0013] Optionally, the coupling coil includes at least two turns of coil wound in the axial direction.

[0014] According to another aspect of the present invention, a DC arc detection device is provided, comprising: a DC arc coupling device, a filter, and a controller as described in any embodiment of the present invention; wherein the filter is used to filter the signal output by the DC arc coupling device, and the controller is used to determine whether an arc has been generated based on the filtered signal.

[0015] According to another aspect of the present invention, a component-level product is provided, comprising: a main circuit and a DC arc coupling device as described in any embodiment of the present invention; wherein the main circuit is configured as a hollow structure, and the DC arc coupling device is used to couple a DC arc to the main circuit.

[0016] This invention provides a DC arc coupling device including a coupling coil. The distance between the coupling coil and the main circuit is less than a first preset distance, and the distance between the center of the coupling coil and the center of the hollow structure of the main circuit is less than a second preset distance. This allows the coupling coil to couple the DC arc generated in the main circuit. During normal operation of the main circuit, the current in the main circuit is DC. When an arc exists in the main circuit, there is also an AC component. The coupling coil can couple the AC component in the main circuit, thereby detecting the DC arc in the main circuit. Furthermore, the coupling coil and the main circuit are as close as possible, and the distance between the centers of their hollow structures is also as close as possible, which helps to improve the coupling coefficient of the coupling coil. Also, the coupling coil provided in this invention is a hollow structure (i.e., without a magnetic core), eliminating the possibility of magnetic core saturation, so that the coupling coefficient of the coupling coil is not limited by the current magnitude or the frequency bandwidth. Furthermore, the hollow structure (i.e., without a magnetic core) of the coupling coil provided in this invention results in a smaller size, which is beneficial for its installation in component-level products and other products. The DC arc coupling device provided in this invention has a simple structure, low raw material cost, and simple manufacturing process, which helps to reduce the overall cost and is easy to implement. Therefore, this invention expands the application scope of DC arc detection and improves the accuracy of DC arc detection.

[0017] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a DC arc coupling device provided in an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of a first-layer coupling coil provided in an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of a second-layer coupling coil provided in an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of a third-layer coupling coil provided in an embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure of a fourth-layer coupling coil provided in an embodiment of the present invention;

[0024] Figure 6 This is a schematic diagram of the structure of a first-layer main circuit provided in an embodiment of the present invention;

[0025] Figure 7 This is a schematic diagram of the structure of a second-layer main circuit provided in an embodiment of the present invention;

[0026] Figure 8 This is a schematic diagram of another DC arc coupling device provided in an embodiment of the present invention;

[0027] Figure 9 For along Figure 8 A schematic diagram of the cross-sectional structure of AA. Detailed Implementation

[0028] 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 of the present invention. 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 scope of protection of the present invention.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] This invention provides a DC arc coupling device that can be applied to module-level products of photovoltaic systems (such as power optimizers or fast shutdown devices). Figure 1 This is a schematic diagram of a DC arc coupling device provided in an embodiment of the present invention. See also... Figure 1 The DC arc coupling device includes a coupling coil 100. The distance between the coupling coil 100 and the main circuit 200 is less than a first preset distance, and the distance between the center of the coupling coil 100 and the center of the hollow structure of the main circuit 200 is less than a second preset distance. The coupling coil 100 is used to couple the DC arc generated in the main circuit 200.

[0031] There are various ways to arrange the coupling coil 100 and the main circuit 200. For example, they can be stacked along the axial direction of the winding of the coupling coil 100, or they can be nested in a direction perpendicular to the axial direction of the winding of the coupling coil 100.

[0032] exist Figure 1 In this example, the coupling coil 100 and the main circuit 200 are stacked along the axial direction of the coil winding. The red coil at the top layer is the coupling coil 100, and the blue portion at the bottom layer is the main circuit 200. The distance between the coupling coil 100 and the main circuit 200 being less than a first preset distance means that the coupling coil 100 and the main circuit 200 are as close as possible while ensuring reliable insulation. Therefore, the first preset distance can be set as needed in practical applications.

[0033] The main circuit 200 is configured as a hollow structure, which can be circular or approximately circular in shape. The coupling coil 100 can also be circular or approximately circular in shape, and the coupling coil 100 is also a hollow structure. The distance between the center of the coupling coil 100 and the center of the hollow structure of the main circuit 200 is less than a second preset distance, meaning that the distance between the centers of the two hollow structures (including the hollow structure of the coupling coil 100 and the hollow structure of the main circuit 200) is less than the second preset distance. That is, the centers of the hollow structures (including the hollow structure of the coupling coil 100 and the hollow structure of the main circuit 200) are as close as possible, preferably coinciding. In other words, the hollow structure of the coupling coil 100 and the hollow structure of the main circuit 200 are concentric circles, and can be represented as circle 300.

[0034] This embodiment of the invention utilizes a DC arc coupling device including a coupling coil 100. The distance between the coupling coil 100 and the main circuit 200 is less than a first preset distance, and the distance between the center of the coupling coil 100 and the center of the hollow structure of the main circuit 200 is less than a second preset distance. This allows the coupling coil 100 to couple the DC arc generated in the main circuit 200. During normal operation of the main circuit 200, the current in the main circuit 200 is DC. When an arc exists in the main circuit 200, an AC component also exists. The coupling coil 100 can couple the AC component in the main circuit 200, thereby detecting the DC arc in the main circuit 100. Furthermore, the coupling coil 100 and the main circuit 200 are positioned as close as possible, and the distance between the centers of their hollow structures is also minimized, which helps to improve the coupling coefficient of the coupling coil 100. Furthermore, the coupling coil 100 provided in this embodiment of the invention has a hollow structure (i.e., no magnetic core), eliminating the possibility of core saturation. This ensures that the coupling coefficient of the coupling coil 100 is not limited by the current magnitude or the frequency bandwidth. Moreover, the hollow structure (i.e., no magnetic core) of the coupling coil 100 in this embodiment of the invention results in a smaller size, which is advantageous for integration into component-level products. The DC arc coupling device provided in this embodiment of the invention has a simple structure, low raw material costs, and a simple manufacturing process, which helps reduce overall costs and is easy to implement. Therefore, this embodiment of the invention expands the application scope of DC arc detection and improves the accuracy of DC arc detection.

[0035] See also Figure 1Based on the above embodiments, optionally, both the coupling coil 100 and the main circuit 200 are disposed on a circuit board (i.e., PCB); the coupling coil 100 and the main circuit 200 are located in different wiring layers of the circuit board, and the wiring layer where the coupling coil 100 is located is adjacent to the wiring layer where the main circuit 200 is located. This arrangement, on the one hand, facilitates the flattening design of the DC arc coupling device, reducing its size; on the other hand, having both the coupling coil 100 and the main circuit 200 disposed on the circuit board helps ensure the consistency of the coupling coil 100 and the main circuit 200, thereby further improving the accuracy of arc detection. Therefore, the embodiments of the present invention are further advantageous for application in component-level products.

[0036] See also Figure 1 Based on the above embodiments, optionally, a single-layer coupling coil 100 includes at least two turns of coil arranged in concentric circles. Figure 1 Taking the red coil at the top layer as an example, this red coil is wound seven times from the inside out. This arrangement helps to enhance the signal strength of the arc coupled to the coupling coil 100, thereby improving the accuracy and sensitivity of arc detection.

[0037] See also Figure 1 Based on the above embodiments, optionally, the coupling coil 100 has at least two layers, and the at least two layers of coupling coils are arranged in concentric circles; the coupling coils of different layers are located in different wiring layers and are electrically connected through vias. This arrangement helps to enhance the signal strength of the arc coupled to the coupling coil 100, and improve the detection accuracy and sensitivity of the arc.

[0038] For example, in Figure 1 It contains red, orange, green, and yellow coils. Below, we will combine... Figures 2-5 Further explanation of the specific configuration of the coupling coils in each layer.

[0039] Figure 2 This is a schematic diagram of the structure of a first-layer coupling coil provided in an embodiment of the present invention. See also... Figure 2 The coupling coil 110 is located on the top layer of the circuit board, connected to an external power supply through via 101, and connected to the next layer coupling coil through via 102.

[0040] Figure 3 This is a schematic diagram of a second-layer coupling coil provided in an embodiment of the present invention. See also... Figure 3 The coupling coil 120 is located on the second layer of the circuit board, connected to the coupling coil 110 through via 102, and connected to the coupling coil on the next layer through via 103.

[0041] Figure 4This is a schematic diagram of a third-layer coupling coil provided in an embodiment of the present invention. See also... Figure 4 The coupling coil 130 is located on the third layer of the circuit board, connected to the coupling coil 120 through via 103, and connected to the coupling coil on the next layer through via 104.

[0042] Figure 5 This is a schematic diagram of a fourth-layer coupling coil provided in an embodiment of the present invention. See also... Figure 5 The coupling coil 140 is located on the fourth layer of the circuit board, connected to the coupling coil 130 through via 104, and connected to an external power supply through via 105.

[0043] Therefore, the first-layer coupling coil 110, the second-layer coupling coil 120, the third-layer coupling coil 130, and the fourth-layer coupling coil 140 are connected in series to form the power supply circuit for the coil. Furthermore, each layer of coupling coils forms a concentric circle with circle 300, meaning each layer of coupling coils is designed as a concentric circle. This arrangement helps to enhance the signal strength of the arc coupled to the coupling coil 100, thereby improving the accuracy of arc detection.

[0044] Based on the above embodiments, optionally, the main circuit 200 has at least two layers; the main circuits 200 on different layers are located in different wiring layers and are electrically connected through vias. This configuration is beneficial for improving the current carrying capacity of the main circuit 200. The following describes... Figures 6-7 Further explanation of the specific configuration of the main circuits at each level.

[0045] Figure 6 This is a schematic diagram of the structure of a first-layer main circuit provided in an embodiment of the present invention. See also... Figure 6 The main circuit 210 is located on the fifth layer of the circuit board. It is connected to the external main circuit through vias 201 and to the main circuit of the next layer through vias 202. Since the current flowing through the main circuit is relatively large, the copper area of ​​the main circuit 210 is relatively large, and the number of vias 201 and 202 is also relatively large, which helps to improve the reliability of the current flow path of the main circuit.

[0046] Figure 7 This is a schematic diagram of a second-layer main circuit provided in an embodiment of the present invention. See also... Figure 7 The main circuit 220 is located on the sixth layer of the circuit board. It is connected to the main circuit 210 through vias 202 and to the external main circuit through vias 203. Since the current flowing through the main circuit is relatively large, the copper area of ​​the main circuit 220 is relatively large, and the number of vias 203 is also relatively large, which helps to improve the reliability of the current flow path in the main circuit.

[0047] Therefore, the connection between the first-layer main circuit 210 and the second-layer main circuit 220 facilitates the coupling of the main circuit by the coupling coil 100. Furthermore, each layer of main circuits forms a concentric circle with circle 300, meaning each layer of main circuits is designed as a concentric circle.

[0048] Based on the above embodiments, optionally, the coupling coil 100 is bonded to the main circuit 200. For example, in the above embodiments, the fourth-layer coupling coil and the first-layer main circuit are located in two adjacent layers of the circuit, which is a bonded arrangement. This arrangement helps to improve the coupling coefficient of the coupling coil 100, thereby improving the accuracy of arc detection.

[0049] Figure 8 This is a schematic diagram of another DC arc coupling device provided in an embodiment of the present invention. See also... Figure 8 In another embodiment of the present invention, the coupling coil 100 may optionally be sleeved on the outer edge of the main circuit 200. This configuration is equivalent to setting the coupling coil 100 as a column, with the main circuit 200 located inside the coupling coil 100, eliminating the need to mount the coupling coil 100 and the main circuit 200 on a circuit board, thereby reducing costs.

[0050] See also Figure 8 Optionally, the coupling coil 100 is provided with terminals 106 and 107, which are used to connect to an external power supply for the coupling coil 100. The main circuit 200 is provided with terminals 204 and 205, which are used to connect to other parts of the main circuit.

[0051] Figure 9 For along Figure 8 A schematic diagram of the cross-sectional structure of AA. (See attached diagram) Figure 8 and Figure 9 Based on the above embodiments, optionally, the coupling coil 100 includes at least two turns of coil wound along the axial direction X. Exemplarily, the coupling coil 100 is provided with four layers, each layer having multiple turns of coupling coil wound. Furthermore, each layer of coupling coil is arranged in a concentric circle, i.e., each layer of coupling coil is designed as a concentric circle. This arrangement helps to enhance the signal strength of the arc coupled to the coupling coil 100, improving the accuracy of arc detection.

[0052] Based on the above embodiments, optionally, the wire used in the main circuit 200 and / or coupling coil 100 is enameled copper, etc., which can be selected as needed in practical applications, as long as its current carrying capacity can be ensured.

[0053] See also Figure 8 and Figure 9Based on the above embodiments, optionally, the coupling coil 100 is attached to the main circuit 200, and the coupling coil 100 is sleeved on the outer edge of the main circuit 200. This arrangement helps to improve the coupling coefficient of the coupling coil 100, thereby improving the accuracy of arc detection.

[0054] In summary, the present invention provides a DC arc coupling device including a coupling coil 100, which is attached to the main circuit 200. The coupling coil 100 and the hollow structure of the main circuit 200 are concentric circles, allowing the coupling coil 100 to couple the DC arc generated in the main circuit 200. During normal operation of the main circuit 200, the current in the main circuit 200 is DC. When an arc exists in the main circuit 200, an AC component also exists. The coupling coil 100 can couple the AC component in the main circuit 200, thereby detecting the DC arc in the main circuit 100. Furthermore, the coupling coefficient of the coupling coil 100 provided in this embodiment can be close to 1. Also, the coupling coil 100 provided in this embodiment has a hollow structure (i.e., no magnetic core), eliminating the possibility of magnetic core saturation, thus the coupling coefficient of the coupling coil 100 is not limited by the current magnitude or the frequency bandwidth. Furthermore, the coupling coil 100 provided in this embodiment of the invention has a hollow structure (i.e., no magnetic core), and its size is small. It can be configured as a flat shape or as a columnar shape fitted with the main circuit 200, which is beneficial for its installation in component-level products and other products. The DC arc coupling device provided in this embodiment of the invention has a simple structure, low raw material cost, and simple manufacturing process, which helps to reduce the overall cost and is easy to implement. Therefore, this embodiment of the invention expands the application scope of DC arc detection and improves the accuracy of DC arc detection.

[0055] This invention also provides a DC arc detection device. This DC arc detection device includes the DC arc coupling device provided in any embodiment of this invention, and has corresponding beneficial effects. Its technical principle and the effects it produces are similar, and will not be described again.

[0056] In addition, the DC arc detection device also includes a filter and a controller; the filter is used to filter the signal output by the DC arc coupling device, and the controller is used to determine whether an arc has been generated based on the filtered signal.

[0057] This invention also provides a component-level product. This component-level product includes a main circuit and a DC arc coupling device provided in any embodiment of this invention, and possesses corresponding beneficial effects. Its technical principle and the resulting effects are similar and will not be described in detail here. The DC arc coupling device is used to couple the DC arc of the main circuit. Specifically, in one embodiment, some coils in the main circuit can be jointly disposed on a circuit board with the coupling coil to achieve a flattened design and improve parameter consistency; in another embodiment, some coils in the main circuit can be wound into a cylindrical shape and nested with the cylindrical coupling coil to simplify the structure.

[0058] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0059] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A direct current arc coupling device, characterized by The coupling coil is arranged in a concentric circle with the hollow structure of the main loop. The coupling coil is arranged in a concentric circle with the hollow structure of the main loop.

2. The direct current arc coupling device of claim 1, wherein, The coupling coil and the main loop are arranged on the circuit board.

3. The direct current arc coupling device of claim 1, wherein, The coupling coil and the main loop are arranged on the circuit board.

4. The device of any one of claims 1-3, wherein the device is configured to operate in a range of 1- 10 kV. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board.

5. The device of claim 4, wherein the arc coupling means is further characterized by: The coupling coil and the main loop are arranged on the circuit board.

6. The device of claim 5, wherein the arc coupling means is further characterized by: The coupling coil and the main loop are arranged on the circuit board.

7. The device of claim 4 wherein, The coupling coil and the main loop are arranged on the circuit board.

8. The device of any one of claims 1-3, wherein the device is a direct current arc coupling device. The coupling coil and the main loop are arranged on the circuit board.

9. The device of claim 8, wherein the arc coupling means is further characterized by: The coupling coil and the main loop are arranged on the circuit board.

10. A direct current arc detection device, characterized by The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board.

11. An assembly level product, characterized by The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. The coupling coil and the main loop are arranged on the circuit board. 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