CN202872353U - Zero-loss deep current-limiting device - Google Patents
Zero-loss deep current-limiting device Download PDFInfo
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- CN202872353U CN202872353U CN 201220527152 CN201220527152U CN202872353U CN 202872353 U CN202872353 U CN 202872353U CN 201220527152 CN201220527152 CN 201220527152 CN 201220527152 U CN201220527152 U CN 201220527152U CN 202872353 U CN202872353 U CN 202872353U
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Abstract
The utility model relates to a zero-loss deep current-limiting device. The device comprises a Rock coil, a high-speed eddy current driving switch, a monitoring unit and a deep current-limiting reactor, the current of a system is monitored through the Rock coil, when a short-circuit current is greater than a set value of amplitude, a high-speed DCP rapidly and accurately predicts the accurate time of the zero crossing points of three-phase currents, and signals are sent out respectively before the zero crossing point of the current of each phase; three phases of the high-speed eddy current driving switch are respectively and accurately switched off when the current approaches each zero crossing point, and the deep current-limiting reactor limits a short-circuit current to below 50% of an original value of amplitude; after a short-circuit fault is removed, a measuring and controlling unit sends out a switching-on command to the high-speed eddy current driving switch, the deep current-limiting reactor exits, and the system returns to normal operation. In an initial phase of the short-circuit current, the zero-loss deep current-limiting device can rapidly use the deep current-limiting reactor to limit the short-circuit current within a reliable range, achieving the purpose of protecting power generation and distribution equipment, and satisfying the requirement of an electric system for short-circuit protection.
Description
Technical field
The utility model relates to a kind of short-circuit protection of electric power system, is specifically related to a kind of zero loss degree of depth current-limiting apparatus.
Background technology
As everyone knows, when electric power system is short-circuited fault, short circuit current is generally tens times of rated current, this causes very large harm for the electric equipments such as transformer, generator, circuit breaker, transmission line, and at present the connecting-disconnecting function of comparatively economical and practical vacuum circuit-breaker is all below 40KA, and switch off time needs a few tens of milliseconds.Along with developing of all types of electricity consumption enterprises, power load is carried out on a large scale soaring, main transformer capacity is corresponding increase also, each enterprise's network system faces the maximum operating limit that short circuit current had approached and reached the load vacuum circuit-breaker, the problems such as load-side vacuum circuit-breaker off-capacity, the design of transformer Short Circuit withstand rush of current ability is not enough, the enterprise security operation in serious threat.
Face the more and more serious short circuit current problem that exceeds standard, a lot of enterprises adopt high-impedance transformer restriction system short circuit current, but transformer strengthens the problem that impedance does not have finally to solve the current limliting degree of depth, and electric power reduces very little, has also brought meritorious reactive loss, cost of investment to rise.
Adopt common series connection current limiting reactor also fundamentally not solve current limliting degree of depth problem (reactor is all about tens percent); the disadvantages such as meritorious reactive loss, bus pressure drop, stray field have been brought simultaneously; it is inadequate owing to the current limliting degree of depth when system is short-circuited; can not effectively protect the electric equipments such as generator, transformer; under huge short-circuit current rush, produce winding deformation and damage the generation catastrophic failure.
Explosive type high-capacity and high-speed breaking device and the reactor parallel running used in the market, although solved the problems such as the meritorious reactive loss of reactor, voltage drop, stray field, but one time components and parts action after the fault that is short-circuited, reactor is devoted oneself to work and is not solved current limliting degree of depth problem.The spare part that the type device need to more renew can put into operation again.The enterprise operation expense not only increases, and has increased space and the connection of the bus between the reactor device that cabinet is installed, and is provided with artificially the potential faults point.
Therefore develop one and rush the quickly and reliably reactor of degree of depth limiting short-circuit current, not only power system security is moved reliably and seem very important, and to reduce equipment cost that electric equipment uses producer also tool be of great significance.
The utility model content
Above-mentioned shortcoming and defect for the prior art existence; the utility model provides a kind of zero loss degree of depth current-limiting apparatus; the utility model can be in the starting stage of short circuit current; drop into fast degree of depth current limiting reactor and be about to short-circuit current limitation in scope reliably; protect the purpose of being transported to electric equipment and supply line thereby reached, satisfy electric power system to the demand of short-circuit protection.
The utility model is achieved through the following technical solutions:
A kind of zero loss degree of depth current-limiting apparatus, comprise: the Rogowski coil of surveillance electric current, at electric current three-phase accurate high-speed eddy driving switch of cut-offfing of separating brake respectively during near zero crossing, sample, calculate, send to the backstage monitoring unit of action index signal, the degree of depth current limiting reactor of limiting short-circuit current; By described Rogowski coil surveillance electric current, when the amplitude of short circuit current greater than setting, the quick accurately predicting of high speed DCP goes out the precise time of three-phase current zero crossing, sends signal respectively before every phase current zero crossing; Described high-speed eddy driving switch electric current during near zero crossing three-phase respectively accurately separating brake cut-off, the short circuit current change of current enters in the described degree of depth current limiting reactor, limiting short-circuit current; Described measurement and control unit sends the action index signal to the backstage, with short-circuit current limitation in former amplitude below 50%; After short trouble was got rid of, described measurement and control unit automatically detected the busbar voltage rise and sends the order of closing a floodgate to described high-speed eddy driving switch immediately, and described degree of depth current limiting reactor withdraws from, and normally operation recovers in system.
Preferably, described degree of depth current limiting reactor is dry-type hollow degree of depth current limiting reactor.
Preferably, described zero loss degree of depth current-limiting apparatus also comprises anti-contact percussion device, guarantees to close a floodgate without bounce-back.
The beneficial effects of the utility model are as follows: when occuring without short trouble in system, the reactor impedance is minimum; When system was short-circuited fault, the reactor impedance increased, and after system short-circuit fault is got rid of, returned immediately former operating state.The utility model can be in the starting stage of short circuit current; drop into fast degree of depth current limiting reactor and be about to short-circuit current limitation in scope reliably; making protection be transported to the short-circuit current rush that electric equipment and supply line be subject to reduces greatly; protect the purpose of being transported to electric equipment and supply line thereby reached, satisfy electric power system to the demand of short-circuit protection.
Description of drawings
Fig. 1 is structural representation of the present utility model.
Embodiment
Below in conjunction with specific embodiment the utility model is elaborated.Following examples will help those skilled in the art further to understand the utility model, but not limit in any form the utility model.Should be pointed out that to those skilled in the art, without departing from the concept of the premise utility, can also make some distortion and improvement.These all belong to protection range of the present utility model.
Zero loss degree of depth current-limiting apparatus as shown in Figure 1, comprise: the Rogowski coil 2 of surveillance electric current, at electric current three-phase accurate high-speed eddy driving switch 3 of cut-offfing of separating brake respectively during near zero crossing, sample, calculate, send to the backstage monitoring unit 1 of action index signal, the dry-type hollow degree of depth current limiting reactor 4 of limiting short-circuit current; By described Rogowski coil surveillance electric current, when the amplitude of short circuit current greater than setting, the quick accurately predicting of high speed DCP goes out the precise time of three-phase current zero crossing, sends signal respectively before every phase current zero crossing; Described high-speed eddy driving switch electric current during near zero crossing three-phase respectively accurately separating brake cut-off, the short circuit current change of current enters in the described degree of depth current limiting reactor, limiting short-circuit current; Described measurement and control unit sends the action index signal to the backstage, with short-circuit current limitation in former amplitude below 50%; After short trouble was got rid of, described measurement and control unit automatically detected the busbar voltage rise and sends the order of closing a floodgate to described high-speed eddy driving switch immediately, and described degree of depth current limiting reactor withdraws from, and normally operation recovers in system.
Operation principle of the present utility model is as follows:
This device is by Rogowski coil surveillance electric current, when short circuit current greater than the amplitude of setting, high speed DCP dopes the precise time of three-phase current zero crossing fast accurately by fixing algorithm, sent signal respectively before every phase current zero crossing;
Speed-sensitive switch electric current during near zero crossing three-phase respectively accurately separating brake cut-off, the short circuit current change of current enters in the dark current limiting reactor, limiting short-circuit current, amplitude of short circuit reduces greatly;
Measurement and control unit sends the action index signal to the backstage, in 7～15 milliseconds with short-circuit current limitation in former amplitude below 50%, the suffered short-circuit impact of system is reduced greatly, the electric equipments such as transformer and generator in the protection system, improve simultaneously short dot load vacuum circuit-breaker useful life, guaranteed the security of system operation;
After short trouble was got rid of, measurement and control unit automatically detected the busbar voltage rise and sends the order of closing a floodgate to speed-sensitive switch immediately, and dark current limiting reactor withdraws from, and normal operation can recover in system.
Characteristics of the present utility model are as follows:
1, quick action
In 7～15 milliseconds that this device can be short-circuited in system short circuit current is cut-off, degree of depth current limiting reactor is down to short circuit current below 50%.Use the high-speed eddy driving switch in this device, can realize 5 milliseconds with interior separating brake, 10 milliseconds of combined floodgates.Measurement and control unit uses high accuracy, high-speed A/D converter simultaneously, constantly system power is detected, when electric current during greater than set point, by high-speed dsp technology and fixing algorithm, in you, and sent actuating signal before zero crossing, driving switch cut off circuit before zero crossing in quick accurate moment of calculating short circuit current and current zero-crossing point in 2 milliseconds, guarantee that the arcing time is the shortest, in 7～15 milliseconds, short circuit current is changed in the dark current limiting reactor.
2, long service life
Switch uses the high-speed eddy driving mechanism in this device, reduces 80% than the employed spring operating mechanism moving component of common short-circuiting device, and uses simple rectilinear motion, does not have complicated transmission mechanism, weares and teares minimum, and mechanical endurance and reliability improve.Simultaneously, this device is that zero crossing cut-offs, and the arcing amount during the arcing is cut-off capacity and greatly improved less than 10% of normal circuit breaker, contact burns little, and its contact electric life is progression and rises, and when dark current limiting reactor occurs without short circuit, is in zero loss, do not generate heat, without pressure drop, long service life.
3, the action decentralization is little
Because shortened significantly closing time and configured the high-speed eddy driving mechanism of direct driving, the combined floodgate decentralization is controlled in 0.1 millisecond.
The utility model scope of application is as follows:
1, this device can replace high-impedance transformer, common series connection current limiting reactor, explosive type high-capacity and high-speed breaking device, when new electricity supplying and using system design and business system transformation, can utilize this device, strengthen system impedance, the drop-out current of load side circuit breaker is further reduced, reduce cost, therefore, this device is energy-conservation and cost-effective current limliting scheme;
This device just dropped into mother degree of depth current limiting reactor fast when 2, short circuit occured, anti-in the increasing system, after the fault point is got rid of, degree of depth current limiting reactor just withdraws from, do not affect the normal operation of whole system, networking operation is improved the use value of transformer, greatly reduces system's enlarging or the required investment of networking operation;
3, during line short, this device drops into reactor fast, and the residual voltage on the dark current limiting reactor can satisfy fully keeps that important load continues to move and unaffected, to not allowing the by force important load of self-starting of instantaneous interruptedly supplying power, can improve power supply quality;
4, to cut-off capacity large for this device, and limiting short-circuit current is dark, is the ideal protection equipment of generator outlet and house branch bus, and generator and transformer are protected fast and effectively.
Environment for use condition of the present utility model is as follows:
1, ambient temperature :-40 ℃～50 ℃;
2, height above sea level: generally be not more than 2000 meters, greater than 2000 meters particular design;
3, field of employment: without the acid and alkali corrosion place;
4, relative humidity: per day relative humidity is not more than 95%.
Claims (3)
1. zero loss degree of depth current-limiting apparatus, it is characterized in that, comprise: the Rogowski coil of surveillance electric current, at electric current three-phase accurate high-speed eddy driving switch of cut-offfing of separating brake respectively during near zero crossing, sample, calculate, send to the backstage monitoring unit of action index signal, the degree of depth current limiting reactor of limiting short-circuit current; By described Rogowski coil surveillance electric current, when the amplitude of short circuit current greater than setting, the quick accurately predicting of high speed DCP goes out the precise time of three-phase current zero crossing, sends signal respectively before every phase current zero crossing; Described high-speed eddy driving switch electric current during near zero crossing three-phase respectively accurately separating brake cut-off, the short circuit current change of current enters limiting short-circuit current in the described degree of depth current limiting reactor; Described measurement and control unit sends the action index signal to the backstage, with short-circuit current limitation in former amplitude below 50%; After short trouble was got rid of, described measurement and control unit automatically detected the busbar voltage rise and sends the order of closing a floodgate to described high-speed eddy driving switch immediately, and described degree of depth current limiting reactor withdraws from, and normally operation recovers in system.
2. zero loss degree of depth current-limiting apparatus according to claim 1 is characterized in that, described degree of depth current limiting reactor is dry-type hollow degree of depth current limiting reactor.
3. zero loss degree of depth current-limiting apparatus according to claim 1 and 2 is characterized in that, described zero loss degree of depth current-limiting apparatus also comprises anti-contact percussion device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220527152 CN202872353U (en) | 2012-10-16 | 2012-10-16 | Zero-loss deep current-limiting device |
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| CN 201220527152 CN202872353U (en) | 2012-10-16 | 2012-10-16 | Zero-loss deep current-limiting device |
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| CN 201220527152 Expired - Fee Related CN202872353U (en) | 2012-10-16 | 2012-10-16 | Zero-loss deep current-limiting device |
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Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105470929A (en) * | 2015-12-16 | 2016-04-06 | 安徽合凯电气科技股份有限公司 | Discrete lossless deep current-limiting device |
| CN106208006A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of transformator zero consumes degree of depth current-limiting method |
| CN106208004A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of momentary power failure can maintain the current-limiting method of voltage |
| CN106208008A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of important load bus residual voltage keeps system |
| CN106208002A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of important load bus residual voltage keeping method |
| CN106208007A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | The degree of depth current-limiting method that a kind of transformator and electromotor share |
| CN106208005A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of zero consume degree of depth current-limiting apparatus |
| CN106207952A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of momentary power failure can maintain the current limiting system of voltage |
| CN106207951A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | The degree of depth current limiting system that a kind of transformator and electromotor share |
| CN106253227A (en) * | 2016-08-28 | 2016-12-21 | 安徽普天电力科技有限公司 | A kind of generator outlet high-pressure side current limiting system |
| CN106300233A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of new transformator degree of depth current limiting system |
| CN106300231A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of generator outlet high-pressure side current-limiting method |
| CN106300261A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of new transformator degree of depth current-limiting method |
| CN106300306A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of transformator zero consumes degree of depth current limiting system |
| CN106300305A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of zero consume degree of depth current-limiting method |
| CN106329490A (en) * | 2016-08-28 | 2017-01-11 | 安徽普天电力科技有限公司 | Bus residual voltage holding method |
| CN106711980A (en) * | 2017-01-23 | 2017-05-24 | 中国南方电网有限责任公司电网技术研究中心 | Modular current limiting device and control method thereof |
| CN107171277A (en) * | 2017-07-03 | 2017-09-15 | 安徽恒凯电力保护设备有限公司 | A kind of zero loss depth current-limiting protection device that technology is cut-off based on Mintrop wave |
| CN109921375A (en) * | 2019-02-02 | 2019-06-21 | 中国电力科学研究院有限公司 | Short circuit current consumption branch withdrawal control method and device based on voltage characteristic |
| CN109921390A (en) * | 2019-02-02 | 2019-06-21 | 中国电力科学研究院有限公司 | Short circuit current consumption branch withdrawal control method and device based on voltage characteristic |
| CN109962447A (en) * | 2019-02-02 | 2019-07-02 | 中国电力科学研究院有限公司 | Short circuit current consumption branch withdrawal control method and device based on overcurrent protection |
| CN114865607A (en) * | 2022-04-21 | 2022-08-05 | 国网伊犁伊河供电有限责任公司 | Zero-loss deep current limiting method and current limiting system |
| CN111952948B (en) * | 2020-08-18 | 2023-04-25 | 广东电网有限责任公司 | Zero-loss deep current limiting device and power transmission line short-circuit fault current limiting method |
-
2012
- 2012-10-16 CN CN 201220527152 patent/CN202872353U/en not_active Expired - Fee Related
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105470929A (en) * | 2015-12-16 | 2016-04-06 | 安徽合凯电气科技股份有限公司 | Discrete lossless deep current-limiting device |
| CN105470929B (en) * | 2015-12-16 | 2018-08-28 | 安徽合凯电气科技股份有限公司 | A kind of lossless depth current-limiting apparatus of discrete |
| CN106208005A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of zero consume degree of depth current-limiting apparatus |
| CN106208006A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of transformator zero consumes degree of depth current-limiting method |
| CN106208002A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of important load bus residual voltage keeping method |
| CN106208007A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | The degree of depth current-limiting method that a kind of transformator and electromotor share |
| CN106208004A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of momentary power failure can maintain the current-limiting method of voltage |
| CN106207952A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of momentary power failure can maintain the current limiting system of voltage |
| CN106207951A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | The degree of depth current limiting system that a kind of transformator and electromotor share |
| CN106253227A (en) * | 2016-08-28 | 2016-12-21 | 安徽普天电力科技有限公司 | A kind of generator outlet high-pressure side current limiting system |
| CN106300233A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of new transformator degree of depth current limiting system |
| CN106300231A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of generator outlet high-pressure side current-limiting method |
| CN106300261A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of new transformator degree of depth current-limiting method |
| CN106300306A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of transformator zero consumes degree of depth current limiting system |
| CN106208008A (en) * | 2016-08-28 | 2016-12-07 | 安徽普天电力科技有限公司 | A kind of important load bus residual voltage keeps system |
| CN106329490A (en) * | 2016-08-28 | 2017-01-11 | 安徽普天电力科技有限公司 | Bus residual voltage holding method |
| CN106300305A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of zero consume degree of depth current-limiting method |
| CN106711980A (en) * | 2017-01-23 | 2017-05-24 | 中国南方电网有限责任公司电网技术研究中心 | Modular current limiting device and control method thereof |
| CN107171277A (en) * | 2017-07-03 | 2017-09-15 | 安徽恒凯电力保护设备有限公司 | A kind of zero loss depth current-limiting protection device that technology is cut-off based on Mintrop wave |
| CN109921375A (en) * | 2019-02-02 | 2019-06-21 | 中国电力科学研究院有限公司 | Short circuit current consumption branch withdrawal control method and device based on voltage characteristic |
| CN109921390A (en) * | 2019-02-02 | 2019-06-21 | 中国电力科学研究院有限公司 | Short circuit current consumption branch withdrawal control method and device based on voltage characteristic |
| CN109962447A (en) * | 2019-02-02 | 2019-07-02 | 中国电力科学研究院有限公司 | Short circuit current consumption branch withdrawal control method and device based on overcurrent protection |
| CN109962447B (en) * | 2019-02-02 | 2022-09-20 | 中国电力科学研究院有限公司 | Short-circuit current absorption branch exit control method and device based on overcurrent protection |
| CN109921375B (en) * | 2019-02-02 | 2023-10-13 | 中国电力科学研究院有限公司 | Short-circuit current absorption branch exit control method and device based on voltage characteristics |
| CN111952948B (en) * | 2020-08-18 | 2023-04-25 | 广东电网有限责任公司 | Zero-loss deep current limiting device and power transmission line short-circuit fault current limiting method |
| CN114865607A (en) * | 2022-04-21 | 2022-08-05 | 国网伊犁伊河供电有限责任公司 | Zero-loss deep current limiting method and current limiting system |
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Legal Events
| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130410 Termination date: 20141016 |
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| EXPY | Termination of patent right or utility model |