High-voltage electricity-taking capacitor circuit and printed circuit board structure

Abstract

The utility model discloses a high-voltage electricity-taking capacitor circuit and a printed circuit board structure, the high-voltage electricity-taking capacitor circuit comprises N RC parallel circuit units, the RC parallel circuit units are connected in series, and N is greater than or equal to 2. The printed circuit board structure comprises RC parallel circuit units and a circuit board, the RC parallel circuit units are connected in series, and the RC parallel circuit units are distributed on the circuit board in an S shape. According to the utility model, the parallel connection and series connection are combined, the voltage dividing capacitor with the corresponding capacitance value is selected for voltage dividing according to the finally reached capacitance value, and the current limiting resistor is matched for current limiting, so that the durability of the product can be improved, the service life of the product is greatly prolonged, and the maintenance cost of the product is reduced.

Description

Technical Field

[0001] The utility model relates to the field of high-voltage power taking, in particular to a high-voltage power taking capacitor circuit and a printed circuit board structure. Background Art

[0002] High-voltage power extraction technology refers to the method of obtaining electrical energy from a high-voltage power supply in a high-voltage power system. This technology is particularly important in power system monitoring, control and protection equipment, because these devices usually need to work in a high-voltage environment, but cannot directly use a high-voltage power supply. In high-voltage power extraction technology, high-voltage power extraction capacitors are indispensable components. High-voltage power extraction capacitors are special capacitors designed to work in a high-voltage environment. It uses the voltage division principle of capacitors to reduce the voltage of the high-voltage power supply to a level suitable for the operation of the equipment.

[0003] At present, most high-voltage power supply capacitor circuits use thin-film capacitors. When used in high-voltage environments, thin-film capacitors are prone to overcurrent or overvoltage, which in turn causes the film capacitor to overheat and cause damage. This has certain defects. Utility Model Content

[0004] The utility model aims to provide a high-voltage power-taking capacitor circuit and a printed circuit board structure to reduce overvoltage or overcurrent phenomena of the high-voltage power-taking capacitor and extend the service life of the high-voltage power-taking capacitor circuit.

[0005] In order to solve the above technical problems, the utility model provides a high-voltage power-taking capacitor circuit, comprising N RC parallel circuit units, and the RC parallel circuit units are connected in series, wherein N≥2.

[0006] Further, the RC parallel circuit unit includes a current limiting resistor and at least one voltage dividing capacitor;

[0007] The current limiting resistor is connected in parallel with the voltage dividing capacitor.

[0008] Furthermore, the current limiting resistor is a glass glaze resistor.

[0009] Furthermore, the voltage-dividing capacitor is a high-voltage ceramic capacitor.

[0010] The utility model also discloses a printed circuit board structure, which adopts the above-mentioned high-voltage power-taking capacitor circuit, including an RC parallel circuit unit and a circuit board;

[0011] The RC parallel circuit units are connected in series, and the RC parallel circuit units are distributed in an S-shaped manner on the circuit board.

[0012] Furthermore, the voltage-dividing capacitor adopts a forward and reverse alternate stacking structure.

[0013] Furthermore, a hollow area is provided on the circuit board, and the hollow area is located below the voltage-dividing capacitor.

[0014] Furthermore, a welding area is provided on the circuit board, and the welding area is used to connect with an external circuit.

[0015] Furthermore, the circuit board is made of a plate material with a thickness of 3.8mm-4.2mm.

[0016] Furthermore, the surface copper foil thickness of the circuit board is 3.8 ounces to 4.2 ounces.

[0017] Compared with the prior art, the utility model has at least the following beneficial effects:

[0018] The utility model is combined in parallel and series, and selects a voltage-dividing capacitor with a corresponding capacitance to divide the voltage according to the capacitance to be finally achieved, and cooperates with a current-limiting resistor to limit the current, which can improve the durability of the product, thereby greatly extending the service life of the product and reducing the maintenance cost of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the high-voltage power-taking capacitor circuit of the utility model;

[0020] Figure 2 The utility model is a schematic diagram of the voltage-dividing capacitor welding structure of the printed circuit board structure. DETAILED DESCRIPTION

[0021] The following will be combined with the schematic diagram to describe the high-voltage power-taking capacitor circuit and printed circuit board structure of the utility model in more detail, wherein the preferred embodiment of the utility model is shown, and it should be understood that those skilled in the art can modify the utility model described herein, and still achieve the beneficial effects of the utility model. Therefore, the following description should be understood as being widely known to those skilled in the art, and not as a limitation to the utility model.

[0022] The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the accompanying drawings are in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0023] Embodiment 1:

[0024] like Figure 1 As shown, an embodiment of the utility model proposes a high-voltage power-taking capacitor circuit, including N RC parallel circuit units, and the RC parallel circuit units are connected in series, wherein N≥2.

[0025] Specifically, the RC parallel circuit unit includes a current limiting resistor and at least one voltage dividing capacitor.

[0026] The current limiting resistor is connected in parallel with the voltage dividing capacitor.

[0027] In this embodiment, capacitors are used in series to reduce the high voltage to the required voltage value for use by other electrical equipment. The high voltage power supply capacitor voltage divider uses the capacitive reactance generated by the capacitor at a certain AC signal frequency to limit the maximum working current. Because the load impedance is not very large, the capacitor at this time is considered to be a constant current source to supply power to the load. According to the inductive reactance and current calculation formula:

[0028]

[0029] Where: f is the operating frequency of the input voltage, c is the total capacitance in the high-voltage power supply capacitor circuit, and U is the input voltage.

[0030] When the voltage-dividing capacitor value is smaller, the capacitive reactance of the high-voltage power-taking capacitor circuit is larger, and the current value of the voltage-dividing capacitor as a constant current source is smaller.

[0031] Among them, the current size is determined according to the working current required by the load. When the working current required by the load is determined, the total capacitance value in the high-voltage power supply capacitor circuit can be calculated according to the formula. When the total capacitance value in the high-voltage power supply capacitor circuit is known, the selection and connection method of the capacitor in the high-voltage power supply capacitor circuit can be determined according to the combination of parallel and series connection of the capacitor.

[0032] In a specific embodiment, the current limiting resistor adopts a glass glaze resistor. The glass glaze resistor uses glass glaze as the resistor body, which is a glaze made of a special glass material with high resistivity. The glass glaze resistor is usually composed of a ceramic core and a glass glaze layer coated thereon. A wire is wound around the core, and the contact between the wire and the glass glaze layer determines the resistance value. In addition, the glass glaze resistor provides good resistance stability and can maintain a stable resistance value even in an environment with changing temperature and humidity.

[0033] In addition, the voltage divider capacitor uses a high-voltage ceramic capacitor. High-voltage ceramic capacitors use ceramic materials as dielectrics. Ceramic is a material with high dielectric strength and is very suitable for high-voltage applications. High-voltage ceramic capacitors are usually small in size, which is convenient for use in compact spaces. At the same time, high-voltage ceramic capacitors have good temperature and voltage stability and can maintain performance under extreme temperatures.

[0034] In the application of 10kV AC power supply to high-voltage power supply by pole-mounted switch, ceramic capacitors with capacitance of 47nF / withstand voltage of 2kV / temperature coefficient of X7R / package of 2220 and glass glaze resistors with resistance of 60MΩ / power of 250mW are selected. Through the method of "4 in parallel and 45 in series", the final capacitance of the power-taking capacitor is calculated as "47nF×3÷45=3133pF". 3133pF is the final capacitance of the power-taking capacitor. The withstand voltage level of 45 series capacitors is "2kV×45=90kV", which is the withstand voltage level of the power-taking capacitor. The 10kV AC power is converted into 3kV DC power through the high-voltage power-taking capacitor circuit and the equipment is powered.

[0035] Embodiment 2:

[0036] like Figure 1 As shown, the utility model also discloses a printed circuit board 2 structure, which adopts the above-mentioned high-voltage power-taking capacitor circuit and includes an RC parallel circuit unit and a circuit board 2.

[0037] The RC parallel circuit units are connected in series, and the RC parallel circuit units are distributed in an S-shaped manner on the circuit board 2 .

[0038] Specifically, the high-voltage power supply capacitor circuit is layout-designed on the circuit board 2 , and the circuit board 2 is used to mechanically support and electrically connect the circuit components, so as to realize the function of high-voltage power supply on the circuit board 2 .

[0039] In order to facilitate the series connection of the high-voltage power-taking capacitor circuit with the input end and the load end, a welding area is provided on the circuit board 2, and the welding area is used to connect with an external circuit.

[0040] The two welding areas are respectively located at the two ends of the high voltage power supply capacitor circuit and are electrically connected to the ends of the high voltage power supply capacitor circuit. The welding area is designed on both sides of the circuit board 2, and a butt joint can be welded in the welding area for connecting with the input end and the load end.

[0041] In addition, if Figure 2 As shown, a hollow area 3 is provided on the circuit board 2, and the hollow area 3 is located below the voltage-dividing capacitor 1. By providing the hollow area 3 below the voltage-dividing capacitor 1 to increase the creepage distance of the voltage-dividing capacitor 1, leakage can be reduced and the insulation performance of the device can be improved.

[0042] Furthermore, the voltage-dividing capacitor 1 adopts a forward and reverse alternating stacking structure.

[0043] Specifically, the stacking of capacitors in both positive and negative directions usually refers to a structural design used in the manufacture of multilayer ceramic capacitors (MLCC). This design can increase the capacitance of the capacitor while reducing its size. The design of stacking in both positive and negative directions helps to improve the performance of the capacitor, including its capacitance, stability and withstand voltage.

[0044] Furthermore, the circuit board 2 is made of a plate material with a thickness of 3.8 mm to 4.2 mm, and the surface copper foil thickness of the circuit board 2 is 3.8 ounces to 4.2 ounces.

[0045] Specifically, the circuit board 2 can also use 3.9mm, 4.0mm and 4.1mm thick plates, and the surface copper foil thickness can also be 3.9 ounces, 4.0 ounces and 4.1 ounces. The surface pads of the circuit board are treated with gold, and the 0.8mm vias are treated with copper paste plugging to improve the conductivity and current carrying capacity of the board.

[0046] Among them, the chemical gold treatment process usually refers to a surface treatment process for printed circuit boards (PCBs) in the field of electronic manufacturing. The chemical gold treatment process has the following excellent properties:

[0047] (1) The gold layer has excellent welding properties, is easy to weld and has high welding quality.

[0048] (2) The gold layer can protect the copper surface from oxidation and extend the storage time of the PCB.

[0049] (3) The gold layer has good conductivity and corrosion resistance, which helps to improve the stability and reliability of the circuit.

[0050] In addition, the copper paste plugging process is a technology in the manufacture of printed circuit boards (PCBs) that is used to fill copper paste in the vias of PCBs to achieve electrical connections between inner and outer layers. The copper paste plugging process has the following excellent properties:

[0051] (1) Good conductivity: Copper paste filling provides a good conductive path, which helps signal transmission.

[0052] (2) Higher reliability: Copper paste filling enhances the bonding strength between the hole wall and the PCB, improving reliability.

[0053] (3) Adaptability: Suitable for different types of PCBs, including rigid boards, flexible boards, and rigid-flexible boards.

[0054] Compared with the prior art, the utility model has at least the following beneficial effects:

[0055] The utility model is combined in parallel and series, and selects a voltage-dividing capacitor with a corresponding capacitance to divide the voltage according to the capacitance to be finally achieved, and cooperates with a current-limiting resistor to limit the current, which can improve the durability of the product, thereby greatly extending the service life of the product and reducing the maintenance cost of the product.

[0056] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A high voltage power supply capacitor circuit, characterized in that: It includes N RC parallel circuit units, and the RC parallel circuit units are connected in series, wherein N≥2.

2. The high voltage power supply capacitor circuit according to claim 1, characterized in that: The RC parallel circuit unit includes a current limiting resistor and at least one voltage dividing capacitor; The current limiting resistor is connected in parallel with the voltage dividing capacitor.

3. The high voltage power supply capacitor circuit according to claim 2, characterized in that: The current limiting resistor is a glass glaze resistor.

4. The high voltage power supply capacitor circuit according to claim 2, characterized in that: The voltage-dividing capacitor is a high-voltage ceramic capacitor.

5. A printed circuit board structure, using the high-voltage power supply capacitor circuit as described in any one of claims 1 to 4, characterized in that: It includes an RC parallel circuit unit and a circuit board; The RC parallel circuit units are connected in series, and the RC parallel circuit units are distributed in an S-shaped manner on the circuit board.

6. The printed circuit board structure according to claim 5, characterized in that: The voltage-dividing capacitors adopt a forward and reverse alternate stacking structure.

7. The printed circuit board structure according to claim 5, characterized in that: A hollow area is provided on the circuit board, and the hollow area is located below the voltage-dividing capacitor.

8. The printed circuit board structure according to claim 5, characterized in that: A welding area is provided on the circuit board, and the welding area is used to connect with an external circuit.

9. The printed circuit board structure according to claim 5, characterized in that: The circuit board is made of a plate material with a thickness of 3.8mm-4.2mm.

10. The printed circuit board structure according to claim 5, characterized in that: The surface copper foil thickness of the circuit board is 3.8 ounces to 4.2 ounces.

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