CN112490094A - Current-limiting air direct-current circuit breaker arc extinguishing device and arc extinguishing method thereof - Google Patents
Current-limiting air direct-current circuit breaker arc extinguishing device and arc extinguishing method thereof Download PDFInfo
- Publication number
- CN112490094A CN112490094A CN202011532038.5A CN202011532038A CN112490094A CN 112490094 A CN112490094 A CN 112490094A CN 202011532038 A CN202011532038 A CN 202011532038A CN 112490094 A CN112490094 A CN 112490094A
- Authority
- CN
- China
- Prior art keywords
- current
- arc extinguishing
- mechanical fracture
- arc
- mechanical
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H73/00—Protective overload circuit-breaking switches in which excess current opens the contacts by automatic release of mechanical energy stored by previous operation of a hand reset mechanism
- H01H73/02—Details
- H01H73/18—Means for extinguishing or suppressing arc
Landscapes
- Arc-Extinguishing Devices That Are Switches (AREA)
Abstract
本发明公开了，一种限流式空气直流断路器灭弧装置，包括安装在接线端子上的两个并联灭弧室；两个并联的灭弧室分别带有机械断口S1和机械断口S2；机械断口S1和机械断口S2分别连接两动导杆；两动导杆中的一个通过并联电阻与接线端子连接。当线路故障发生短路时，根据采集到的电流信号，将机械断口S1断开，电流通过并联电阻与机械断口S2形成闭合回路；接着，断开机械断口S2，电弧熄灭，成功切断故障线路。由于机械断口S2打开时，电流很小，对触头和栅片的烧蚀很小，因此提高了断路器的电寿命。由于没用永磁体，因此消除了直流电流极性的影响，实现了直流无极性开断。
The invention discloses an arc extinguishing device for a current-limiting air-to-DC circuit breaker, comprising two parallel arc extinguishing chambers installed on the connection terminals; the two parallel arc extinguishing chambers are respectively provided with a mechanical fracture S1 and a mechanical fracture S 2 ; the mechanical fracture S1 and the mechanical fracture S2 are respectively connected to two movable guide rods; one of the two movable guide rods is connected to the connection terminal through a parallel resistance. When the line fault is short-circuited, according to the collected current signal, the mechanical fracture S 1 is disconnected, and the current forms a closed loop with the mechanical fracture S 2 through the parallel resistance; then, the mechanical fracture S 2 is disconnected, the arc is extinguished, and the fault is successfully cut off line. Since the current is very small when the mechanical fracture S2 is opened, the ablation of the contacts and the grid is very small, so the electrical life of the circuit breaker is improved. Since no permanent magnet is used, the influence of the polarity of the DC current is eliminated, and the DC non-polarity interruption is realized.
Description
Technical Field
The invention belongs to the technical field of arc extinction of low-voltage direct-current circuit breakers, relates to a current-limiting air direct-current circuit breaker arc extinction device and further relates to an arc extinction method of the arc extinction device.
Background
In recent years, the wide application of distributed energy photovoltaic power generation and wind power generation promotes the rapid development of a direct-current micro-grid and an alternating-current and direct-current hybrid power distribution network, and the requirements on a direct-current circuit breaker for protecting a photovoltaic power generation system and the alternating-current and direct-current hybrid power distribution network are more and more strict. On the one hand, the voltage of the direct current side is required to be continuously improved, and on the other hand, in order to save cost, the volume of the power distribution cabinet does not rise or fall reversely, so that the volume of the direct current breaker is required to be smaller and smaller. The breaking performance of the circuit breaker mainly depends on the arc extinguishing performance, namely whether the circuit breaker can be successfully broken or not and whether the electric arc can be rapidly extinguished or not. Direct current arc is different from alternating current arc, and direct current arc does not have natural zero crossing point, so arc extinction is more difficult, and for traditional mechanical circuit breaker, need to cut off the electric arc of high voltage, usually by multipolar series connection to improve arc voltage, force arc current zero crossing, thereby make direct current arc extinguish.
For DC1500V DC arc, 3-pole or 4-pole series connection is usually required to successfully cut off the short circuit current, but this is contrary to the current demand for circuit breaker miniaturization. Therefore, higher system voltages and smaller circuit breaker volumes constitute the core difficulties in the development of dc circuit breakers. Therefore, many circuit breaker manufacturers improve the single-pole arc extinguishing performance by adding the permanent magnet and the gas generating material, so as to realize the miniaturization design of the high-voltage circuit breaker, but the cost is increased on one hand, and on the other hand, due to the existence of the permanent magnet, the non-polarity on-off requirement of the direct-current circuit breaker is difficult to realize.
Disclosure of Invention
The invention aims to provide an arc extinguishing device of a current-limiting air direct-current circuit breaker and an arc extinguishing method thereof, and solves the problem that the arc extinguishing chamber in the prior art has a large volume because 3 poles or 4 poles are connected in series and can break short-circuit current.
The technical scheme adopted by the invention is that the current-limiting air direct current breaker arc extinguishing device comprises two parallel arc extinguishing chambers arranged on a wiring terminal; two parallel arc-extinguishing chambers are respectively provided with a mechanical fracture S1And mechanical fracture S2(ii) a Mechanical fracture S1And mechanical fracture S2Are respectively connected with two movable guide rods; one of the two movable guide rods is connected with the wiring terminal through a parallel resistor.
The tail ends of the two movable guide rods are connected and fixed through a series copper plate, and a movable guide rod connecting lead is connected between the two movable guide rods.
One end of the parallel resistor passes through a mechanical fracture S on the resistor lead and the wiring terminal1The stationary contact at one side is connected, and the other end is connected with the series copper plate through a resistance wire.
The resistance of the parallel resistor is 2-3 times of the resistance of the line resistor.
The invention is also characterized in that:
an arc extinguishing method of an arc extinguishing device of a current-limiting air direct current breaker comprises the following specific steps:
The invention has the beneficial effects that:
1) the invention not only does not need to greatly reform the arc extinguish chamber structure of the original circuit breaker, but also can improve the on-off voltage and on-off short-circuit current of the whole circuit breaker and greatly improve the on-off performance of the circuit breaker.
2) Because the arc extinguish chamber does not need to add gas production materials and permanent magnets, the cost of the whole product is reduced, meanwhile, the short-circuit current under high voltage is cut off, and the cut-off can be realized only by 2 poles of the original mechanical circuit breaker at most, the volume of the whole circuit breaker is greatly reduced, and the miniaturization design requirement of the circuit breaker is realized.
3) Due to mechanical fracture S2When the circuit breaker is opened, the current is small, and the ablation on the contact and the grid piece is small, so that the electric service life of the circuit breaker is prolonged.
4) Because the permanent magnet is not used, the influence of the polarity of the direct current is eliminated, and the direct current non-polarity switching-on and switching-off are realized.
5) When short-circuit current occurs, the loop resistance is equivalently increased due to the existence of the parallel resistance, the circuit time constant is reduced, and meanwhile, the electric arc energy injected into the mechanical fracture is reduced due to the consumption of the resistance on the electric arc energy, so that the quick switching-on and switching-off of the electric arc are facilitated.
Drawings
FIG. 1 is a structural diagram of an arc extinguishing device of a current-limiting air DC circuit breaker;
FIG. 2 is a mechanical port structure diagram of the arc extinguishing device of the current-limiting type air DC circuit breaker;
FIG. 3 is a schematic circuit diagram of the arc extinguishing device of the current-limiting type air DC circuit breaker and the arc extinguishing method thereof;
fig. 4 is a schematic diagram of a current path during normal operation in the arc extinguishing apparatus and the arc extinguishing method of the current-limiting type air dc circuit breaker according to the present invention;
fig. 5 is a schematic diagram of a current circulation path during a short-circuit fault in the arc extinguishing apparatus and the arc extinguishing method of the current-limiting type air dc breaker according to the present invention.
In the figure, 1, a connecting terminal, 2, an arc extinguish chamber, 3, a stationary contact, 4, a resistor wire, 5, a parallel resistor, 6, a movable guide rod connecting wire, 7, a series copper plate and 8, a mechanical fracture S29. mechanical fracture S1。
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.
As shown in fig. 1-2, an arc extinguishing device of a current-limiting air direct current circuit breaker comprises two parallel arc extinguishing chambers 2 mounted on a connecting terminal 1; the two parallel arc-extinguishing chambers 2 are respectively provided with a mechanical fracture S19 and mechanical fracture S 28; mechanical fracture S19 and mechanical fracture S 28 are respectively connected with two movable guide rods; one of the two movable guide rods is connected with the wiring terminal 1 through a parallel resistor 5. The parallel resistor 5 is connected in parallel between the mechanical fractures of any one-pole arc extinguish chamber 2, so that the current limiting effect is realized, and the purpose of effectively reducing the size of the device under high voltage is achieved.
In the invention, each arc extinguishing chamber 2 is of a conventional design and comprises a plurality of arc extinguishing grid pieces. The operating mechanism of the movable contact is also independent in each arc extinguishing chamber 2.
The tail ends of the two movable guide rods are fixedly connected through a series copper plate 7, and a movable guide rod connecting lead 6 is connected between the two movable guide rods.
One end of the parallel resistor 5 passes through the resistorMechanical fracture S on wire 4 and connecting terminal 11The stationary contact 3 on one side of 9 is connected, and the other end is connected with a series copper plate 7 through a resistance wire 4.
The resistance of the parallel resistor 5 is 2-3 times of the resistance of the line resistor.
Due to the parallel resistor 5, on the one hand, the total resistance in the whole circuit is increased, thereby reducing the short-circuit current, namely, the current limiting function is realized. On the other hand, mechanical fracture S is reduced28, the arc energy when the breaker is opened accelerates the arc extinguishing and simultaneously improves the service life of the breaker.
As shown in fig. 3 to 5, an arc extinguishing method of an arc extinguishing device of a current-limiting air dc circuit breaker includes the following specific steps:
when the circuit is normally switched on, the direct current breaker switches on rated current, and the mechanical fracture S of the two arc extinguish chambers 2 connected in series19 and mechanical fracture S 28 are both closed, at which point the parallel resistance 5 is short-circuited and the current passes through the mechanical break S19 and mechanical fracture S 28 form a loop, mechanical break S19 and mechanical fracture S 28, the resistance is very small, and the circuit loss is basically 0;
The invention not only does not need to greatly reform the arc extinguish chamber structure of the original circuit breaker, but also can improve the on-off voltage and on-off short-circuit current of the whole circuit breaker.
Example 1
For a dc high voltage line, the system voltage is dc1500V, and a short circuit current of 15kA is expected.
According to known conditions, the line resistance R1 is calculated to be 0.1 Ω, if the parallel resistance is designed to be R2 ═ 0.2 Ω, when the mechanical break S is broken1After disconnection, the in-line resistance became 0.3 Ω in sum of the line resistance and the parallel resistance R2. At this time, the short-circuit current i in the line is 1500/0.3 to 5 kA. The short circuit current before current limiting is reduced 2/3. Mechanical fracture S2The voltage at two ends is 1500V when the circuit is disconnected, but the short-circuit current is only 5kA, and the mechanical fracture S2It will be easy to switch off the small short-circuit current.
The invention has the following advantages:
1) the invention not only does not need to greatly reform the arc extinguish chamber structure of the original circuit breaker, but also can improve the on-off voltage and on-off short-circuit current of the whole circuit breaker and greatly improve the on-off performance of the circuit breaker.
2) Because the arc extinguish chamber does not need to add gas production materials and permanent magnets, the cost of the whole product is reduced, meanwhile, the short-circuit current under high voltage is cut off, and the cut-off can be realized only by 2 poles of the original mechanical circuit breaker at most, the volume of the whole circuit breaker is greatly reduced, and the miniaturization design requirement of the circuit breaker is realized.
3) Due to mechanical fracture S2When the circuit breaker is opened, the current is small, and the ablation on the contact and the grid piece is small, so that the electric service life of the circuit breaker is prolonged.
4) Because the permanent magnet is not used, the influence of the polarity of the direct current is eliminated, and the direct current non-polarity switching-on and switching-off are realized.
5) When short-circuit current occurs, the loop resistance is equivalently increased due to the existence of the parallel resistance, the circuit time constant is reduced, and meanwhile, the electric arc energy injected into the mechanical fracture is reduced due to the consumption of the resistance on the electric arc energy, so that the quick switching-on and switching-off of the electric arc are facilitated.
Claims (5)
1. A current-limiting air direct current breaker arc extinguishing device is characterized by comprising two parallel arc extinguishing chambers (2) arranged on a wiring terminal (1); the two parallel arc-extinguishing chambers (2) are respectively provided with a mechanical fracture S1(9) And mechanical fracture S2(8) (ii) a Mechanical fracture S1(9) And mechanical fracture S2(8) Are respectively connected with two movable guide rods; one of the two movable guide rods is connected with the wiring terminal (1) through a parallel resistor (5).
2. The arc extinguishing device of the current-limiting type air direct current breaker according to claim 1, wherein the tail ends of the two movable guide rods are connected and fixed through a series copper plate (7), and a movable guide rod connecting lead (6) is connected between the two movable guide rods.
3. An arc extinguishing device of a current-limiting air direct current breaker according to claim 2, characterized in that one end of the parallel resistor (5) is mechanically disconnected from the terminal (1) by a resistor wire (4) and a mechanical break S1(9) The fixed contact (3) at one side is connected, and the other end is connected with the series copper plate (7) through a resistance wire (4).
4. A current limiting type air dc breaker arc extinguishing device according to claim 2, characterized in that the resistance of the parallel resistor (5) is 2-3 times the resistance of the line resistor.
5. The arc extinguishing method of the arc extinguishing device of the current-limiting type air direct current breaker according to the claims 1 to 4, characterized by comprising the following specific steps:
step 1, when a short circuit occurs due to a line fault, a mechanical fracture S is cut off according to the collected current signal1(9) Cut off, the current passes through the parallel resistor (5) and the mechanical fracture S2(8) Forming a closed loop;
step 2, then, the mechanical fracture S is disconnected2(8) The arc is extinguished and the faulty line is successfully cut off.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011532038.5A CN112490094B (en) | 2020-12-22 | 2020-12-22 | Current-limiting type air direct current breaker arc extinguishing device and arc extinguishing method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011532038.5A CN112490094B (en) | 2020-12-22 | 2020-12-22 | Current-limiting type air direct current breaker arc extinguishing device and arc extinguishing method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112490094A true CN112490094A (en) | 2021-03-12 |
| CN112490094B CN112490094B (en) | 2024-07-19 |
Family
ID=74915334
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011532038.5A Active CN112490094B (en) | 2020-12-22 | 2020-12-22 | Current-limiting type air direct current breaker arc extinguishing device and arc extinguishing method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112490094B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113517163A (en) * | 2021-07-23 | 2021-10-19 | 西安理工大学 | An arc extinguishing chamber of a high-voltage current-limiting high-voltage circuit breaker with strong air blowing |
| CN114062912A (en) * | 2021-10-29 | 2022-02-18 | 国网安徽省电力有限公司宣城供电公司 | Short-circuit current breaking capacity detection device of vacuum circuit breaker |
| CN119208040A (en) * | 2024-11-26 | 2024-12-27 | 杭州布雷科检测技术有限公司 | Delay pre-processing fast breaker and arc-free breaking control circuit and method |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1465084A (en) * | 2001-06-22 | 2003-12-31 | Abb服务有限公司 | Modular four-pole residual current circuit breaker |
| CN1967753A (en) * | 2006-11-24 | 2007-05-23 | 西安交通大学 | A high-speed double-break magnetic blowing middle-pressure great electric current direct current current-limiting circuit breaker |
| CN102024633A (en) * | 2010-12-03 | 2011-04-20 | 常熟开关制造有限公司(原常熟开关厂） | Arc striking/extinguishing mechanism of low-voltage circuit breaker |
| CN102360991A (en) * | 2011-09-30 | 2012-02-22 | 中国电力科学研究院 | High voltage direct current breaker with multiple fractures and tandem type |
| CN102592911A (en) * | 2012-02-22 | 2012-07-18 | 西安交通大学 | Medium-pressure direct-current large-current arc extinction system with current limiting and breaking function and limiting method of system |
| CN104241058A (en) * | 2014-09-03 | 2014-12-24 | 江苏江城电气有限公司 | Current open circuit arc extinguishing device and method based on nonlinear resistor |
| CN204215989U (en) * | 2014-05-16 | 2015-03-18 | 北京人民电器厂有限公司 | A kind of circuit breaker being beneficial to electric arc fast moving and elongation |
| CN106024505A (en) * | 2016-06-30 | 2016-10-12 | 河南平芝高压开关有限公司 | Arc-extinguishing chamber and circuit breaker using the same |
| CN106298351A (en) * | 2016-10-24 | 2017-01-04 | 上海电力学院 | The extra high voltage circuit breaker of over-voltage |
| CN107731593A (en) * | 2017-09-14 | 2018-02-23 | 西安交通大学 | A kind of solid dielectric plug-in type differential of the arc direct current cut-offs breaker and its cutoff method |
| US20180248362A1 (en) * | 2017-02-27 | 2018-08-30 | Huazhong University Of Science And Technology | Fault current limiter |
| CN109378257A (en) * | 2018-12-27 | 2019-02-22 | 沈阳二三控制电器制造有限公司 | It is a kind of to improve the D.C. contactor for extinguishing disjunction DC load electric arc ability |
-
2020
- 2020-12-22 CN CN202011532038.5A patent/CN112490094B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1465084A (en) * | 2001-06-22 | 2003-12-31 | Abb服务有限公司 | Modular four-pole residual current circuit breaker |
| CN1967753A (en) * | 2006-11-24 | 2007-05-23 | 西安交通大学 | A high-speed double-break magnetic blowing middle-pressure great electric current direct current current-limiting circuit breaker |
| CN102024633A (en) * | 2010-12-03 | 2011-04-20 | 常熟开关制造有限公司(原常熟开关厂） | Arc striking/extinguishing mechanism of low-voltage circuit breaker |
| CN102360991A (en) * | 2011-09-30 | 2012-02-22 | 中国电力科学研究院 | High voltage direct current breaker with multiple fractures and tandem type |
| CN102592911A (en) * | 2012-02-22 | 2012-07-18 | 西安交通大学 | Medium-pressure direct-current large-current arc extinction system with current limiting and breaking function and limiting method of system |
| CN204215989U (en) * | 2014-05-16 | 2015-03-18 | 北京人民电器厂有限公司 | A kind of circuit breaker being beneficial to electric arc fast moving and elongation |
| CN104241058A (en) * | 2014-09-03 | 2014-12-24 | 江苏江城电气有限公司 | Current open circuit arc extinguishing device and method based on nonlinear resistor |
| CN106024505A (en) * | 2016-06-30 | 2016-10-12 | 河南平芝高压开关有限公司 | Arc-extinguishing chamber and circuit breaker using the same |
| CN106298351A (en) * | 2016-10-24 | 2017-01-04 | 上海电力学院 | The extra high voltage circuit breaker of over-voltage |
| US20180248362A1 (en) * | 2017-02-27 | 2018-08-30 | Huazhong University Of Science And Technology | Fault current limiter |
| CN107731593A (en) * | 2017-09-14 | 2018-02-23 | 西安交通大学 | A kind of solid dielectric plug-in type differential of the arc direct current cut-offs breaker and its cutoff method |
| CN109378257A (en) * | 2018-12-27 | 2019-02-22 | 沈阳二三控制电器制造有限公司 | It is a kind of to improve the D.C. contactor for extinguishing disjunction DC load electric arc ability |
Non-Patent Citations (2)
| Title |
|---|
| 武胜斌;姜旭;吴杰;许中;王海斌;王勇;: "应用HCSR和并联灭弧室提高气体断路器开断能力的研究", 高压电器, no. 04 * |
| 贾博文;武建文;孙凡雯;罗晓武;蒋原;马速良;金巍;: "直流大功率无极性换流式多触头接触器设计与试验研究", 电器与能效管理技术, no. 06 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113517163A (en) * | 2021-07-23 | 2021-10-19 | 西安理工大学 | An arc extinguishing chamber of a high-voltage current-limiting high-voltage circuit breaker with strong air blowing |
| CN113517163B (en) * | 2021-07-23 | 2023-02-28 | 西安理工大学 | Strong air-blowing current-limiting type arc extinguish chamber of high-voltage circuit breaker |
| CN114062912A (en) * | 2021-10-29 | 2022-02-18 | 国网安徽省电力有限公司宣城供电公司 | Short-circuit current breaking capacity detection device of vacuum circuit breaker |
| CN119208040A (en) * | 2024-11-26 | 2024-12-27 | 杭州布雷科检测技术有限公司 | Delay pre-processing fast breaker and arc-free breaking control circuit and method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112490094B (en) | 2024-07-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112490094B (en) | Current-limiting type air direct current breaker arc extinguishing device and arc extinguishing method thereof | |
| CN213583681U (en) | Circuit breaker | |
| JPH11339582A (en) | Breaker | |
| CN213184182U (en) | Switch electric appliance | |
| CN107731593B (en) | A kind of solid dielectric plug-in type differential of the arc direct current cut-offs breaker and its cutoff method | |
| CN201215780Y (en) | Contact tip component for high-voltage isolation switch | |
| CN107146723B (en) | Magnetic blow-out system, arc extinguishing device, single-pole circuit breaker and multi-pole circuit breaker | |
| CN111863465B (en) | A double-station circuit breaker and applied DC combined electrical appliance and working method | |
| CN114649153A (en) | Switch | |
| CN103578834A (en) | Outdoor low-voltage protection isolation switch | |
| CN107393777B (en) | Moulded case circuit breaker with high breaking performance | |
| CN201886996U (en) | Circuit breaker with compulsory arc partitioning device | |
| CN107527773B (en) | Universal circuit breaker with arc extinguishing performance | |
| Chung et al. | Arc extinction structure of air circuit breaker for improvement of direct current breaking performance | |
| CN212392149U (en) | Breaking unit with electrodynamic force compensation and automatic dual-power transfer switch | |
| CN213184178U (en) | Contact mechanism and switching device | |
| CN201266574Y (en) | High-voltage vacuum breaker for back-to-back double explosion chambers | |
| CN204270968U (en) | A double-break vacuum switch module of a multi-break high-voltage vacuum circuit breaker | |
| CN107342196B (en) | Arc extinguishing device of high-breaking plastic casing type circuit breaker | |
| CN221352643U (en) | Arc extinguishing structure of circuit breaker | |
| CN213716827U (en) | A fast breaking device based on short-circuit current induction field strength | |
| CN221352666U (en) | Wire outlet structure from two side directions of fixed contact and moving contact of circuit breaker | |
| CN112863953B (en) | Asynchronous double-break contact mechanism and residual current operated circuit breaker | |
| CN217485324U (en) | Switch | |
| CN215680594U (en) | Flow guide structure of molded case circuit breaker |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20210312 Assignee: Zhejiang Benben New Energy Technology Co.,Ltd. Assignor: XI'AN University OF TECHNOLOGY Contract record no.: X2024980014475 Denomination of invention: A current limiting air DC circuit breaker arc extinguishing device and its arc extinguishing method Granted publication date: 20240719 License type: Common License Record date: 20240910 |