阅读说明：本技术 一种低压浪涌保护器 (Low-voltage surge protector ) 是由 陈影月 成先贤 于 2020-05-25 设计创作，主要内容包括：本发明公开了一种低压浪涌保护器,属于浪涌保护器领域,其包括通过并联组合成保护器的氧化锌阀片与碳化硅阀片,氧化锌阀片平均每毫米厚度电场强度为20-25V/mm,最大通流为100A,碳化硅阀片平均每毫米厚度电场强度为36-45V/mm,当电压低于100V时,碳化硅阀片的泄露电流为0.2-0.4mA,碳化硅阀片的动作电压小于氧化锌阀片的动作电压。本发明集浪涌、消磁、过电压为一体,充分利用了高能碳化硅发片低泄露以及高能氧化锌发片钳压迅速平稳的特性,提前构建释放通道,使之不产生浪涌过电压,能量过大的浪涌直接钳制吸收,从而有效弥补了传统浪涌保护器在0-100V低电压电力系统中的不足。(The invention discloses a low-voltage surge protector, which belongs to the field of surge protectors and comprises a zinc oxide valve plate and a silicon carbide valve plate which are combined into a protector in parallel, wherein the average electric field intensity per millimeter of the zinc oxide valve plate is 20-25V/mm, the maximum through-flow is 100A, the average electric field intensity per millimeter of the silicon carbide valve plate is 36-45V/mm, when the voltage is lower than 100V, the leakage current of the silicon carbide valve plate is 0.2-0.4mA, and the action voltage of the silicon carbide valve plate is smaller than the action voltage of the zinc oxide valve plate. The invention integrates surge, demagnetization and overvoltage, fully utilizes the characteristics of low leakage of the high-energy silicon carbide hair piece and rapid and stable clamping of the high-energy zinc oxide hair piece, constructs a release channel in advance, prevents the generation of surge overvoltage, and directly clamps and absorbs the surge with overlarge energy, thereby effectively making up the defects of the traditional surge protector in a 0-100V low-voltage power system.)

1. A low-voltage surge protector is characterized in that: the device comprises a first nonlinear resistance valve plate and a second nonlinear resistance valve plate which are combined into a protector in parallel, wherein the first nonlinear resistance valve plate is a zinc oxide valve plate, the average electric field intensity per millimeter thickness of the first nonlinear resistance valve plate is 20-25V/mm, the maximum through current is 100A, the second nonlinear resistance valve plate is a silicon carbide valve plate, the average electric field intensity per millimeter thickness of the second nonlinear resistance valve plate is 36-45V/mm, when the voltage is lower than 100V, the leakage current of the second nonlinear resistance valve plate is 0.2-0.4mA, and the action voltage of the second nonlinear resistance valve plate is smaller than that of the first nonlinear resistance valve plate.

2. A low voltage surge protector according to claim 1, wherein: the first nonlinear resistance valve plate comprises the following ingredients in parts by weight: 98-99 parts of zinc oxide powder, 1-1.5 parts of conductive carbon black and 0.3-1 part of binder.

3. A low voltage surge protector according to claim 1, wherein: the second nonlinear resistance valve plate comprises the following ingredients in parts by weight: 98-99 parts of silicon carbide powder, 1-1.5 parts of conductive carbon black and 0.3-1 part of binder.

4. A low voltage surge protector according to claim 2 or 3, wherein: the environment-friendly and environment-friendly composite material also comprises plant ash, wherein the plant ash is compounded with the zinc oxide powder and the silicon carbide powder according to the weight ratio of 1: 13.

5. A low voltage surge protector according to claim 2 or 3, wherein: the adhesive is prepared by mixing the following components in parts by weight: 25-35 parts of anionic clay, 10-15 parts of acetylene black, 5-10 parts of corn starch and 40-50 parts of water.

6. A low voltage surge protector according to claim 5, wherein: the preparation process of the first nonlinear resistance valve plate comprises the following steps:

(1) preparing materials: weighing zinc oxide powder, conductive carbon black and a binder in corresponding parts by weight according to a formula of the first nonlinear resistance valve plate;

(2) mixing materials;

(3) drying and forming: drying the slurry mixed in the step (2), and forming by adopting a stamping type press to form a first nonlinear resistance valve plate blank;

(4) pre-burning: placing the first nonlinear resistance valve plate blank in the step (3) in a sintering furnace, controlling the temperature to be 490-510 ℃, and keeping for 2-3 hours;

(5) spraying: introducing hydrogen into the sintering furnace after the pre-sintering in the step (4), heating to 1400-1600 ℃, and then preserving heat for 70-75 hours to form a first nonlinear resistor valve plate semi-finished product; and then cooling the first nonlinear resistance valve plate semi-finished product to 650-750 ℃ along with a furnace, taking out, spraying aluminum electrodes on two end surfaces of the first nonlinear resistance valve plate semi-finished product, continuously cooling naturally, and spraying insulating paint on the side surface of the first nonlinear resistance valve plate semi-finished product.

7. A low voltage surge protector according to claim 5, wherein: the preparation process of the second nonlinear resistance valve plate comprises the following steps:

(1) preparing materials: according to the formula of the second nonlinear resistance valve plate, weighing the silicon carbide powder, the conductive carbon black and the binder in corresponding parts by weight;

(2) mixing materials;

(3) drying and forming: drying the slurry mixed in the step (2), and forming by adopting a stamping type press to form a second nonlinear resistance valve plate blank;

(4) pre-burning: placing the second nonlinear resistance valve plate blank in the step (3) in a sintering furnace, controlling the temperature to be 490-510 ℃, and keeping for 2-3 hours;

(5) spraying: introducing hydrogen into the sintering furnace after the pre-sintering in the step (4), heating to 1400-1600 ℃, and then preserving heat for 70-75 hours to form a second nonlinear resistance valve plate semi-finished product; and then cooling the second nonlinear resistance valve plate semi-finished product to 650-750 ℃ along with the furnace, taking out, spraying aluminum electrodes on two end surfaces of the second nonlinear resistance valve plate semi-finished product, continuously cooling naturally, and spraying insulating paint on the side surface of the second nonlinear resistance valve plate semi-finished product.

Technical Field

The invention relates to the technical field of surge protectors, in particular to a low-voltage surge protector.

Background

The rapid development of modern industry brings convenience, high efficiency and huge economic benefits to people, meanwhile, a plurality of large-capacity power electronic devices are adopted in a power grid, such as variable frequency air conditioners which are used in large quantities in cities and countryside, thyristor converter devices which are adopted in large-scale factories and the like, due to the nonlinear, impact and unbalanced frequently-switched power utilization characteristics, the power grid pollution is caused to a public power grid, a large amount of harmonic waves are injected, surge overvoltage is generated, interference is brought to the normal work of a plurality of electronic devices, instruments and meters and communication lines, and some serious devices can also damage precise components.

To eliminate over-currentThe common practice in the industry at present is to install a surge protector. The traditional surge protector adopts a zinc oxide valve plate, the valve plate material shows non-ohmic conductance, the leakage current of the valve plate material under normal working voltage is far less than 1mA, and the zinc oxide ceramic material has overhigh threshold voltage (the lowest threshold voltage U)_1mA160V), the single chip can be too small (the maximum through-flow is 60A), and the like, so that the surge protection effect is not obvious in the practical application of the low-voltage field of 0-100V; the action voltage is inevitably reduced to obtain an obvious protection effect, and the frequent action of the valve plate inevitably causes serious heating and endangers the safety of the valve plate under the same condition due to the capacity of a single valve plate.

Disclosure of Invention

The invention aims to provide a low-voltage surge protector which has the advantage of improving the surge protection effect in the low-voltage field of 0-100V.

The technical purpose of the invention is realized by the following technical scheme:

a low-voltage surge protector comprises a first nonlinear resistance valve plate and a second nonlinear resistance valve plate which are combined into a protector in parallel, wherein the first nonlinear resistance valve plate is a zinc oxide valve plate, the average thickness per millimeter electric field intensity of the first nonlinear resistance valve plate is 20-25V/mm, the maximum through current is 100A, the second nonlinear resistance valve plate is a silicon carbide valve plate, the average thickness per millimeter electric field intensity of the second nonlinear resistance valve plate is 36-45V/mm, when the voltage is lower than 100V, the leakage current of the second nonlinear resistance valve plate is 0.2-0.4mA, and the action voltage of the second nonlinear resistance valve plate is smaller than that of the first nonlinear resistance valve plate.

By adopting the technical scheme, the silicon carbide valve plate in the application has the characteristic of conventional high capacity, the leakage current is 0.2-0.4mA under the voltage of 100V and is almost zero, the silicon carbide valve plate is in an insulation state, the action voltage of the second nonlinear resistance valve plate is smaller than that of the first nonlinear resistance valve plate, the silicon carbide valve plate starts to work in the protector, and the zinc oxide valve plate works when the voltage is higher than a certain value. The surge protection is carried out by combining the advantages and characteristics of the valve plates made of two different materials, so that the problem that the valve plate made of single zinc oxide is limited in the low-voltage field of 0-100V in the prior art is solved, and a better surge protection effect is achieved.

The present invention in a preferred example may be further configured to: the first nonlinear resistance valve plate comprises the following ingredients in parts by weight: 98-99 parts of zinc oxide powder, 1-1.5 parts of conductive carbon black and 0.3-1 part of binder.

The present invention in a preferred example may be further configured to: the second nonlinear resistance valve plate comprises the following ingredients in parts by weight: 98-99 parts of silicon carbide powder, 1-1.5 parts of conductive carbon black and 0.3-1 part of binder.

The present invention in a preferred example may be further configured to: the environment-friendly and environment-friendly composite material also comprises plant ash, wherein the plant ash is compounded with the zinc oxide powder and the silicon carbide powder according to the weight ratio of 1: 13.

By adopting the technical scheme, the plant ash is the residue after the plant burns, can be used as fuel after being recovered, contains carbon and metal oxide as main components and also contains some trace elements, and is compounded with silicon carbide powder or zinc oxide powder to form the ceramic valve plate after being sintered at high temperature, so that the energy density of the valve plate can be further improved; in addition, the plant ash also belongs to waste recycling, and has excellent energy-saving and environment-friendly effects.

The present invention in a preferred example may be further configured to: the adhesive is prepared by mixing the following components in parts by weight: 25-35 parts of anionic clay, 10-15 parts of acetylene black, 5-10 parts of corn starch and 40-50 parts of water.

By adopting the technical scheme, the specific surface area of the anionic clay is large, and acetylene black and corn starch can be attached to the anionic clay, so that the prepared adhesive has excellent adhesion and good thermal conductivity, and after the adhesive is added into zinc oxide or silicon carbide powder, the compactness of the valve plate after sintering can be improved, and the heat dissipation performance of the valve plate can be promoted.

The present invention in a preferred example may be further configured to: the preparation process of the first nonlinear resistance valve plate comprises the following steps: (1) preparing materials: weighing zinc oxide powder, conductive carbon black and a binder in corresponding parts by weight according to a formula of the first nonlinear resistance valve plate;

(2) mixing materials;

(3) drying and forming: drying the slurry mixed in the step (2), and forming by adopting a stamping type press to form a first nonlinear resistance valve plate blank;

(4) pre-burning: placing the first nonlinear resistance valve plate blank in the step (3) in a sintering furnace, controlling the temperature to be 490-510 ℃, and keeping for 2-3 hours;

(5) spraying: introducing hydrogen into the sintering furnace after the pre-sintering in the step (4), heating to 1400-1600 ℃, and then preserving heat for 70-75 hours to form a first nonlinear resistor valve plate semi-finished product; and then cooling the first nonlinear resistance valve plate semi-finished product to 650-750 ℃ along with a furnace, taking out, spraying aluminum electrodes on two end surfaces of the first nonlinear resistance valve plate semi-finished product, continuously cooling naturally, and spraying insulating paint on the side surface of the first nonlinear resistance valve plate semi-finished product.

By adopting the technical scheme, zinc oxide powder, conductive carbon black, a binder and plant ash are blended, the ingredients are designed for independent research and development, the components are uniformly mixed and dried and sintered, the sintered semi-finished product of the first nonlinear resistance valve plate is cooled along with a furnace, when the temperature is reduced to 650-750 ℃, aluminum electrodes are sprayed to two ends of the valve plate, the surface temperature difference between the aluminum electrodes and the valve plate is small, an aluminum welding wire is quickly melted under the blow-welding action of a spot welding machine and is uniformly coated on the end surface of the valve plate, so that the aluminum electrodes and the valve plate are better combined together, the sealing performance of two ends of the valve plate taking zinc oxide as a main material is remarkably improved, moisture is prevented from invading from an air gap, the generation amount of leakage current is reduced, and the valve plate simultaneously having higher energy density and lower average thickness per millimeter electric field intensity is prepared.

The present invention in a preferred example may be further configured to: the preparation process of the second nonlinear resistance valve plate comprises the following steps: (1) preparing materials: according to the formula of the second nonlinear resistance valve plate, weighing the silicon carbide powder, the conductive carbon black and the binder in corresponding parts by weight;

(2) mixing materials;

(3) drying and forming: drying the slurry mixed in the step (2), and forming by adopting a stamping type press to form a second nonlinear resistance valve plate blank;

(4) pre-burning: placing the second nonlinear resistance valve plate blank in the step (3) in a sintering furnace, controlling the temperature to be 490-510 ℃, and keeping for 2-3 hours;

(5) spraying: introducing hydrogen into the sintering furnace after the pre-sintering in the step (4), heating to 1400-1600 ℃, and then preserving heat for 70-75 hours to form a second nonlinear resistance valve plate semi-finished product; and then cooling the second nonlinear resistance valve plate semi-finished product to 650-750 ℃ along with the furnace, taking out, spraying aluminum electrodes on two end surfaces of the second nonlinear resistance valve plate semi-finished product, continuously cooling naturally, and spraying insulating paint on the side surface of the second nonlinear resistance valve plate semi-finished product.

By adopting the technical scheme, the silicon carbide is a compound material consisting of silicon and carbon, is very stable in the aspects of heat, chemistry and machinery, the SiC has higher carrier mobility and higher energy density, and the SiC power device has the characteristics of high withstand voltage, low loss, high efficiency and the like, and belongs to an ideal power device; silicon carbide powder, conductive carbon black, a binder and plant ash are blended, the ingredients are designed for independent research and development, the components are uniformly mixed, drying and sintering are carried out, the sintered second nonlinear resistance valve plate semi-finished product is cooled along with a furnace, when the temperature is reduced to 650-750 ℃, aluminum electrodes are sprayed to two ends of the valve plate, the surface temperature difference between the aluminum electrodes and the ceramic valve plate is small, an aluminum welding wire is quickly melted under the blow welding action of a spot welding machine and is uniformly coated on the end face of the valve plate, so that the aluminum electrodes and the valve plate are better combined together, the sealing performance of two ends of the ceramic valve plate taking silicon carbide as a main material is remarkably improved, moisture is prevented from invading from an air gap, the generation amount of leakage current is reduced, and the valve plate with high energy density and small leakage current is prepared.

In conclusion, the beneficial technical effects of the invention are as follows:

when the circuit works normally, the protector does not work, the leakage current of the protector is 0, and the normal work of the protected circuit is not influenced at all; when surge occurs in the circuit, the voltage is only slightly higher than normal working voltage at the moment, the protector starts to work, the second nonlinear valve plate made of silicon carbide materials provides a discharge channel for surge overvoltage at the moment, leakage current flows through the discharge channel, electromagnetic energy is converted into heat energy through the valve plate in time, the purposes of energy consumption and demagnetization are achieved, the protector can work for a long time due to the fact that the energy density of the second nonlinear resistor valve plate is large, when overlarge surge impact and overvoltage impact occur, the protector starts to convert the second nonlinear resistor valve plate into the first nonlinear resistor valve plate made of zinc oxide materials to work, the overvoltage can be clamped rapidly, and the effect of surge absorption is achieved. Because the energy release channel is formed in the actual operation switching process, surge overvoltage can not be generated.

Drawings

Fig. 1 is a schematic diagram for embodying an operating circuit of the protector in the fifth embodiment.

Fig. 2 is a schematic diagram of a current-voltage characteristic principle for embodying the operation of the low-voltage surge protector in the fifth embodiment.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Acetylene black was purchased from acetylene black produced by Tianjin Yibo Rui chemical Co., Ltd, CAS: 1333-86-4; corn starch was purchased from suzhou blue-jet chemical technology ltd, CAS: 9005-25-8; the plant ash is purchased from Xinghua Sannong plant ash Co., Ltd; the anionic clay was prepared according to the method described in "preparation and characterization of anionic clay and study of its adsorption property to DNA" published by Li bin, university of south China's Rich chemical industry ".