A nonlinear metal oxide resistor and its preparation method

Abstract

This invention discloses a nonlinear metal oxide resistor, comprising: a resistor body with a ring structure; and a discharge gap disposed within the inner hole of the resistor body, connected in parallel with the resistor body. The nonlinear metal oxide resistor provided by this invention enables the discharge gap to remain non-conductive under a DC 1mA reference voltage, ensuring the high resistivity of the resistor in the low-current region. Under lightning impulse / operational impulse residual voltage, the discharge gap breaks down, and the resistor's residual voltage value decreases due to the short circuit caused by the parallel gap. After the impulse residual voltage is exhausted, the gap returns to an open-circuit state, restoring the resistor's high resistivity in the low-current region and ensuring the resistor's charge rate. Furthermore, this invention employs parallel gap discharge and arc extinguishing, controlling space charge within the internal space and reducing the impact of space charge on the overall insulation performance of the surge arrester.

Description

Technical Field

[0001] This invention relates to the field of nonlinear metal oxide resistors for high-voltage surge arresters, and particularly to a nonlinear metal oxide resistor. This invention also relates to a method for preparing the aforementioned nonlinear metal oxide resistor.

[0002] Methods for preparing physical resistive elements. Background Technology

[0003] Nonlinear metal oxide resistant elements are the core components of metal oxide surge arresters, such as nonlinear zinc oxide resistant elements. Therefore, nonlinear metal oxide resistant elements are a key component that determines the performance of surge arresters. The core function of surge arresters is protection against lightning / switching overvoltages. High DC reference voltage and low residual voltage protection levels are requirements for future development. Currently, resistant elements cannot meet the needs of ultra-high voltage and high-altitude surge arresters.

[0004] Therefore, how to develop a resistor element that meets the requirements of ultra-high voltage and high-altitude surge arresters is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a nonlinear metal oxide resistor to meet the requirements of ultra-high voltage and high-altitude surge arresters.

[0006] Another object of the present invention is to provide a method for preparing the above-mentioned nonlinear metal oxide resistor.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A nonlinear metal oxide resistor includes:

[0009] The main body of the resistor element has a ring-shaped structure;

[0010] The discharge gap is located in the inner hole of the resistor body and is connected in parallel with the resistor body.

[0011] Optionally, in the above-mentioned nonlinear metal oxide resistor, the discharge gap is connected to the resistor body by means of casting with a thermosetting material.

[0012] Optionally, in the above-mentioned nonlinear metal oxide resistor, the thermosetting material is epoxy resin.

[0013] Optionally, in the above-mentioned nonlinear metal oxide resistor, the discharge gap is a sealed discharge gap filled with a discharge protection gas.

[0014] Optionally, in the above-mentioned nonlinear metal oxide resistor, the discharge gap includes:

[0015] The connecting plate is a metal plate, including a first connecting plate and a second connecting plate. A sealed cavity is formed between the first connecting plate and the second connecting plate. The first connecting plate is electrically connected to one end face of the resistor body through a connecting electrode, and the second connecting plate is electrically connected to the other end face of the resistor body through another connecting electrode.

[0016] The gap is provided on both the first connecting plate and the second connecting plate, and the gaps on the first connecting plate and the second connecting plate are arranged opposite to each other in the sealed cavity.

[0017] Optionally, the height of the discharge gap is the same as the height of the resistor body, and the end face of the discharge gap is parallel to the end face of the resistor body.

[0018] Optionally, in the above-mentioned nonlinear metal oxide resistor, the connecting plate is an aluminum plate.

[0019] Optionally, in the above-mentioned nonlinear metal oxide resistor, the connecting plate and the gap are an integral structure.

[0020] Optionally, in the above-mentioned nonlinear metal oxide resistor, the head of the gap is spherical.

[0021] A method for fabricating a nonlinear metal oxide resistor, wherein the nonlinear metal oxide resistor is a resistor as described in any of the preceding claims, and the fabrication method comprises the following steps:

[0022] S1: Create the discharge gap;

[0023] S2: Prefabricate the resistor sheet body using a model;

[0024] S3: Place the discharge gap in the inner hole of the resistor body and cast thermosetting material.

[0025] S4: Connecting electrodes are placed at the top and bottom ends of the discharge gap and the resistor body respectively to achieve electrical connection between the discharge gap and the resistor body, thus forming a resistor.

[0026] The nonlinear metal oxide resistor provided by this invention includes a resistor body and a discharge gap. The resistor body has a ring structure, and the discharge gap is located in the inner hole of the resistor body and connected in parallel with the resistor body. Because the resistor body and the discharge gap are connected in parallel, the nonlinear metal oxide resistor provided by this invention ensures that the discharge gap is non-conductive under a DC 1mA reference voltage, guaranteeing the high resistivity of the resistor in the low-current region. Under lightning impulse / operational impulse residual voltage, the discharge gap breaks down and discharges, and the resistor is short-circuited due to the parallel gap, thus reducing the residual voltage value of the resistor. After the impulse residual voltage is released, the gap returns to an open-circuit state, restoring the high resistivity of the resistor in the low-current region and ensuring the charge rate of the resistor. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the 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.

[0028] Figure 1 This is a cross-sectional view of the nonlinear metal oxide resistor sheet disclosed in an embodiment of the present invention;

[0029] Figure 2 The explosion of the nonlinear metal oxide resistor disclosed in the embodiments of the present invention Figure 1 ;

[0030] Figure 3 The explosion of the nonlinear metal oxide resistor disclosed in the embodiments of the present invention Figure 2 ;

[0031] Figure 4 This is a diagram of the combination of nonlinear metal oxide resistors disclosed in an embodiment of the present invention;

[0032] Figure 5 This is a schematic flowchart of the nonlinear metal oxide resistor fabrication method disclosed in an embodiment of the present invention.

[0033] Figures 1 to 5 The meanings of the various reference numerals in the attached figures are as follows:

[0034] 100 represents the resistor element, and 110 represents the resistor element body.

[0035] 120 is the discharge gap, 121 is the connecting plate, 1211 is the first connecting plate, 1212 is the second connecting plate, and 122 is the gap;

[0036] 130 is a thermosetting material;

[0037] 140 is the connecting electrode. Detailed Implementation

[0038] The core of this invention lies in providing a nonlinear metal oxide resistor to meet the requirements of ultra-high voltage and high-altitude surge arresters.

[0039] Another object of the present invention is to provide a method for preparing the above-mentioned nonlinear metal oxide resistor.

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 are within the scope of protection of the present invention.

[0041] like Figure 1 As shown, an embodiment of the present invention discloses a nonlinear metal oxide resistor, including a resistor body 110 and a discharge gap 120.

[0042] The resistor body 110 has a ring-shaped structure, meaning it has an inner hole. The discharge gap 120 is located within the inner hole of the resistor body 110 and is connected in parallel with it. It should be noted that the discharge gap 120 must be non-conductive during normal operation of the resistor body 100 but conductive under lightning / switching current conditions; this can be achieved through electric field calculations. When manufacturing the resistor body 100, the size of the discharge gap 120 can be adjusted to regulate the initial discharge voltage, ensuring a constant charge rate while reducing the residual voltage. Those skilled in the art will understand that different resistor bodies 100 can be manufactured by adjusting the size of the discharge gap 120 to meet different discharge voltage requirements.

[0043] like Figure 1 As shown, in a specific embodiment of the present invention, the discharge gap 120 is connected to the resistor body 110 by casting with a thermosetting material 130. Thermosetting materials have excellent electrical insulation properties, preventing flashover and breakdown due to the fixing method. Simultaneously, thermosetting materials have strong adhesion, allowing the resistor body 110 and the discharge gap 120 to form a robust whole. Various types of thermosetting materials can be used, such as phenolic resin and polyurethane, and the specific type is not limited here.

[0044] In a specific embodiment of the present invention, the thermosetting material 130 is epoxy resin.

[0045] To reduce the impact of space charge on the overall insulation performance of the surge arrester, in one specific embodiment of the present invention, the discharge gap 120 is a sealed discharge gap filled with a protective discharge gas. By using a sealed discharge gap to extinguish the arc, the space charge is controlled within the sealed space, thus reducing its impact on the overall insulation performance of the surge arrester.

[0046] like Figure 2 As shown, the discharge gap 120 includes a connecting plate 121 and a gap 122. To facilitate parallel connection between the discharge gap 120 and the resistor body 110, the connecting plate 121 is a metal plate; to ensure better connectivity, the connecting plate 121 is preferably made of aluminum. The connecting plate 121 includes a first connecting plate 1211 and a second connecting plate 1212, which together form a sealed cavity. The first connecting plate 1211 is electrically connected to one end face of the resistor body 110 via a connecting electrode 140, and the second connecting plate 1212 is electrically connected to the other end face of the resistor body 110 via another connecting electrode 140. It should be noted that the connecting electrode of the resistor body 110 can be an aluminum electrode. Both the first connecting plate 1211 and the second connecting plate 1212 are provided with gaps 122, and the gaps 122 on the first connecting plate 1211 and the second connecting plate 1212 are arranged opposite to each other in the sealed cavity. The first connecting plate 1211, the second connecting plate 1212 and the gaps 122 together form a discharge gap 120. The gap 122 discharges and extinguishes the arc in the sealed cavity, controlling the space charge within the sealed cavity and reducing the impact of space charge on the overall insulation performance of the surge arrester.

[0047] like Figure 2 and Figure 3 As shown, in order to better realize the parallel connection between the resistor body 110 and the discharge gap 120, based on the above embodiment, the height of the discharge gap 120 is the same as the height of the resistor body 110, and the end face of the discharge gap 120 is parallel to the end face of the resistor body 110. That is, the upper surface of the first connecting plate 1211 is flush with the upper end face of the resistor body 110, and the first connecting plate 1211 is electrically connected to the upper end face of the resistor body 110 through the connecting electrode 140; the lower surface of the second connecting plate 1212 is flush with the lower end face of the resistor body 110, and the second connecting plate 1212 is electrically connected to the lower end face of the resistor body 110 through another connecting electrode 140.

[0048] In a specific embodiment of the present invention, the connecting plate 121 and the gap 122 are an integral structure, that is, the connecting plate 121 and the gap 122 are integrally processed when the discharge gap 120 is manufactured. Specifically, the head of the gap 122 can be spherical, cylindrical, or needle-shaped, and those skilled in the art can select the appropriate type according to the actual situation.

[0049] like Figures 2 to 4 As shown, this invention also discloses a method for preparing a nonlinear metal oxide resistor, comprising the following steps:

[0050] S1: Create a discharge gap of 120;

[0051] S2: Prefabricate the resistor sheet body 110 using a model;

[0052] S3: Place the discharge gap 120 in the inner hole of the resistor body 110 and cast thermosetting material.

[0053] S4: Connecting electrodes are placed at the upper and lower ends of the discharge gap 120 and the resistor body 110 respectively to realize the electrical connection between the discharge gap 120 and the resistor body 110, forming the resistor 100.

[0054] In the above preparation method, the order of steps S1 and S2 can be adjusted, and those skilled in the art can determine the specific order according to the actual situation.

[0055] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0056] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "a," and / or "the" are not specifically singular and may include the plural. Generally, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements. An element defined by the phrase "comprising an..." does not exclude the presence of other identical elements in the process, method, product, or apparatus that includes the element.

[0057] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0058] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A nonlinear metal oxide resistor, characterized in that, include: The resistor body (110) has a ring structure; A discharge gap (120) is disposed in the inner hole of the resistor body (110), and the discharge gap (120) is connected in parallel with the resistor body (110); the discharge gap (120) includes a connecting plate (121) and a gap (122), the connecting plate (121) is a metal plate, including a first connecting plate (1211) and a second connecting plate (1212), the first connecting plate (1211) and the second connecting plate (1212) form a sealed cavity, and the first connecting plate (1211) The first connecting plate (1211) is electrically connected to one end face of the resistor body (110) via a connecting electrode (140), and the second connecting plate (1212) is electrically connected to the other end face of the resistor body (110) via another connecting electrode (140); the first connecting plate (1211) and the second connecting plate (1212) are both provided with the gap (122), and the gap (122) on the first connecting plate (1211) and the second connecting plate (1212) are arranged opposite to each other in the sealed cavity.

2. The nonlinear metal oxide resistor as described in claim 1, characterized in that, The discharge gap (120) is connected to the resistor body (110) by casting with thermosetting material (130).

3. The nonlinear metal oxide resistor as described in claim 2, characterized in that, The thermosetting material (130) is epoxy resin.

4. The nonlinear metal oxide resistor as described in claim 1, characterized in that, The discharge gap (120) is a sealed discharge gap, which is filled with discharge protection gas.

5. The nonlinear metal oxide resistor as described in claim 1, characterized in that, The height of the discharge gap (120) is the same as the height of the resistor body (110), and the end face of the discharge gap (120) is parallel to the end face of the resistor body (110).

6. The nonlinear metal oxide resistor as described in claim 1, characterized in that, The connecting plate (121) is an aluminum plate.

7. The nonlinear metal oxide resistor as described in claim 1, characterized in that, The connecting plate (121) and the gap (122) are an integral structure.

8. The nonlinear metal oxide resistor as described in claim 1, characterized in that, The head of the gap (122) is spherical.

9. A method for preparing a nonlinear metal oxide resistor, characterized in that, The nonlinear metal oxide resistor is the nonlinear metal oxide resistor according to any one of claims 1-8, and the preparation method includes the following steps: S1: Create the discharge gap (120); S2: Prefabricate the resistor sheet body (110) using a model; S3: Place the discharge gap (120) in the inner hole of the resistor body (110) and cast thermosetting material; S4: Connecting electrodes (140) are placed at the upper and lower ends of the discharge gap (120) and the resistor body (110) respectively to realize the electrical connection between the discharge gap (120) and the resistor body (110) and form a resistor (100).

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