CN202121293U - Mining flame-proof and essentially safe concentrated leakage selection protective device - Google Patents
Mining flame-proof and essentially safe concentrated leakage selection protective device Download PDFInfo
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- CN202121293U CN202121293U CN2011201297271U CN201120129727U CN202121293U CN 202121293 U CN202121293 U CN 202121293U CN 2011201297271 U CN2011201297271 U CN 2011201297271U CN 201120129727 U CN201120129727 U CN 201120129727U CN 202121293 U CN202121293 U CN 202121293U
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Abstract
The utility model discloses a mining flame-proof and essentially safe concentrated leakage selection protective device, comprising a sequential discriminating concentrated leakage selection protector, a zero sequence voltage sampling circuit, a zero sequence current sampling and tripping control circuit and an electrical network capacitive current compensation circuit, wherein one end of the zero sequence voltage sampling circuit is connected with an electrical network line, the other end of the zero sequence voltage sampling circuit is connected with the concentrated leakage selection protector, one end of the zero sequence current sampling and tripping control circuit is connected with the electrical network line, the other end of the zero sequence current sampling and tripping control circuit is connected with the concentrated leakage selection protector, and the electrical network capacitive current compensation circuit is parallelly connected at one side of the electrical network line. The mining flame-proof and essentially safe concentrated leakage selection protective device disclosed by the utility model is accurate in line selection and safe. Besides, an essentially safe isolating circuit and an essentially safe operation keyboard are adopted to reduce potential spark energy below energy of a prescribed ignitable gas mixture.
Description
Technical field
The utility model relates to the earth leakage protective field, particularly relates to a kind of mine flameproof and intrinsic safety type and concentrates choosing to leak protective device.
Background technology
Earth leakage protective is one of three big important protections under the coal mine, and the stable operation of personal safety and equipment is played crucial effects.This is because after in the mine leaky taking place, leakage current can cause accidents such as gas, coal-dust explosion; The electric arc that short circuit current produced also possibly burn the shell of flameproof electrical apparatus.
In the prior art, adopt selective leakage protection device that mine is carried out earth leakage protective usually based on the zero sequence power direction principle.Selective leakage protection device can analyze the particular location of circuit electric leakage, selectively corresponding local circuit is carried out earth leakage protective.Therefore, the use of selective leakage protection device, the power failure scope in the time of can shortening earth leakage protective is convenient to seek leak current fault, in time gets rid of, and shortens the electric leakage interruption duration.
Adopting before selective leakage protection device based on the zero sequence power direction principle carries out earth leakage protective to mine, once adopted zero-sequence reactor that the leakage current of supply network is compensated in the prior art.Its principle is, during the human electric shock, through the shock current of human body be current in resistance property and capacity current (cable earth capacitance formations) vector with, can have through zero-sequence reactor to compensate the capacity current that disappears, reduce leakage current greatly, assurance human body safety.
But; Selective leakage protection device of the prior art is owing to adopt the choosing leakage protective device based on the zero sequence power direction principle; If continue to adopt zero-sequence reactor in the power supply grid, thus then during grid power leakage residual voltage, zero-sequence current phase angle can change cause can't the failure judgement phase, non-fault phase.So power system in mines of the prior art has to cancel the zero-sequence reactor compensate function, thus the danger when having increased the human electric shock greatly.
The utility model content
The purpose of the utility model provides a kind of mine flameproof and intrinsic safety type and concentrates choosing to leak protective device, can either have good route selection accuracy, has higher fail safe again.
For realizing above-mentioned purpose, the utility model provides following scheme:
A kind of mine flameproof and intrinsic safety type concentrates choosing to leak protective device, comprising: the sequential identifying concentrates choosing to leak protector, residual voltage sample circuit, zero-sequence current sampling and tripping operation control circuit, and electrical network capacitive current compensation circuit;
Said residual voltage sample circuit one end links to each other with power network line, and the other end leaks protector with said concentrated choosing and links to each other; One end of said zero-sequence current sampling and tripping operation control circuit links to each other with power network line, and the other end leaks protector with said concentrated choosing and links to each other; Said electrical network capacitive current compensation circuit is parallel to a side of power network line.
Preferably, said electrical network capacitive current compensation circuit comprises: first three-phase reactor, compensation reactor and electric capacity;
One end of said first three-phase reactor links to each other with three phase network; The neutral point of said first three-phase reactor connects said compensation reactor; Any tap of said compensation reactor links to each other with said electric capacity; Another tap ground connection of said electric capacity.
Preferably, also comprise: additional dc power supply module and peripheral circuit thereof;
Said peripheral circuit comprises: second three-phase reactor and capacitance-resistance bleeder circuit;
Said second three-phase reactor connects said capacitance-resistance bleeder circuit; Said capacitance-resistance bleeder circuit connects said additional dc power supply module; The neutral point of said second three-phase reactor connects said additional dc power supply module; The output of said additional dc power supply module leaks protector with said concentrated choosing and links to each other.
Preferably, said residual voltage sample circuit comprises: second three-phase reactor, the first zero sequence transformer and the second zero sequence transformer;
The said first zero sequence transformer picks out from the neutral point of said second three-phase reactor, and the secondary coil of the said first zero sequence transformer is imported the said second zero sequence transformer, and the secondary coil of the said second zero sequence transformer is imported said concentrated choosing and leaked protector.
Preferably, said zero-sequence current sampling and tripping operation control circuit comprise: zero sequence current mutual inductor;
Said zero sequence current mutual inductor, each minute that places power network line respectively is in the feeding switch; Said zero sequence current mutual inductor secondary side leak protector through mining shielded type cable and said concentrated choosing and link to each other; The protection action output of protector is leaked in said concentrated choosing, and the separating brake of each vacuum circuit-breaker through total, the branch feeding switch in mining shielded type cable and the power network line is carried out point and linked to each other respectively.
Preferably, also comprise: leak the LCD MODULE that protector links to each other with said concentrated choosing.
Preferably, the circuit breaker auxiliary contact of each feeding switch in said LCD MODULE and the power network line links to each other through lead.
Preferably, also comprise: essential safe type buffer circuit that links to each other with said LCD MODULE and essential safe type operation keyboard.
Preferably, also comprise: essential safe type keyboard division board; Said operation keyboard is connected to said essential safe type keyboard division board input side; Said essential safe type keyboard division board outlet side is connected to said LCD MODULE through netting twine.
Preferably, the housing that mine flameproof and intrinsic safety type concentrates choosing to leak protective device is direct introduction-type blast resistance construction, and opening the door in front and back, is provided with explosion-proof turnover line horn mouth.
The specific embodiment that provides according to the utility model; The utility model discloses following technique effect: owing to adopted the sequential identifying to concentrate choosing to leak protector simultaneously; And electrical network capacitive current compensation circuit, so both had good route selection accuracy, have higher fail safe again.
The utility model has also adopted essential safe type buffer circuit and essential safe type operation keyboard; Potential spark energy is reduced to below the admixture of gas energy that can light regulation, and lead and assembly surface heating temp are limited under the ignition temperature of admixture of gas of regulation.
In addition, through adopting additional dc power supply module and peripheral circuit thereof, the condition in the time of can simulating the human electric shock can be under this condition, and the parameter of adjustment electrical network capacitive current compensation circuit is adjusted to minimum with shock current.Adopt LCD MODULE, can show information such as the position of breaking down and fault type.Adopted the instruction input keyboard, can receive user's query statement, according to user's needs demonstration respective queries information.
Description of drawings
In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art; To do to introduce simply to the accompanying drawing of required use among the embodiment below; Obviously, the accompanying drawing in describing below only is some embodiment of the utility model, for those of ordinary skills; Under the prerequisite of not paying creative work property, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is that the disclosed mine flameproof and intrinsic safety type of the utility model embodiment concentrates choosing to leak the protective device structure chart;
Fig. 2 is an electrical network capacitive current compensation circuit diagram disclosed in the utility model;
Fig. 3 is additional dc power supply module disclosed in the utility model and peripheral circuit diagram thereof;
Fig. 4 is residual voltage sample circuit figure disclosed in the utility model;
Fig. 5 is zero-sequence current sampling disclosed in the utility model and tripping operation control circuit figure.
Embodiment
To combine the accompanying drawing among the utility model embodiment below, the technical scheme among the utility model embodiment is carried out clear, intactly description, obviously, described embodiment only is the utility model part embodiment, rather than whole embodiment.Based on the embodiment in the utility model, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the utility model protection.
The purpose of the utility model provides a kind of mine flameproof and intrinsic safety type and concentrates choosing to leak protective device, can either have good route selection accuracy, has higher fail safe again.
For above-mentioned purpose, the feature and advantage that make the utility model can be more obviously understandable, the utility model is done further detailed explanation below in conjunction with accompanying drawing and embodiment.
Referring to Fig. 1, concentrate choosing for mine flameproof and intrinsic safety type disclosed in the utility model and leak the protective device structure chart.As shown in Figure 1, this device comprises:
The sequential identifying concentrates choosing to leak protector 101, residual voltage sample circuit 102, zero-sequence current sampling and tripping operation control circuit 103, and electrical network capacitive current compensation circuit 104;
One end of said residual voltage sample circuit 102 links to each other with power network line, and the other end leaks protector 101 with said concentrated choosing and links to each other; One end of sampling of said zero-sequence current and tripping operation control circuit 103 places each minute of power supply grid in the feeding switch, and the other end leaks protector 101 with said concentrated choosing and links to each other; Said electrical network capacitive current compensation circuit 104 is parallel to the neutral point of a side of power network line.
Because the operation principle that the sequential identifying concentrates choosing leakage protector 101 and traditional choosing to leak protector is different, its principle is the zero sequence first-harmonic " sequential Identification Theory " of mine low-voltage electricity grid single-phase earthing leak current fault route selection.So, can not influence the accuracy that the protector route selection is leaked in choosing even in power network line, increase electrical network capacitive current compensation circuit yet.
The principle of electrical network capacitive current compensation circuit is: if there is the people to get an electric shock, through the shock current of human body be current in resistance property and capacity current (cable earth capacitance formation) vector and.And the main element in the electrical network capacitive current compensation circuit is an inductive element, can produce inductance current capacity current is compensated (corresponding to the variation on the alternating current phases).For instance, under the situation that does not have the capacitive compensation electric current, suppose that the shock current the when people gets an electric shock is 250mA, after adopting the capacitive compensation circuit, this shock current possibly become 150mA so.Therefore, the setting of electrical network capacitive current compensation circuit can reduce leakage current, guarantees human body safety, improves the fail safe of circuit.
To sum up; Mine flameproof and intrinsic safety type disclosed in the utility model concentrates choosing to leak protective device, owing to adopted the sequential identifying to concentrate choosing to leak protector simultaneously, and electrical network capacitive current compensation circuit; So both had selectivity accurately, had higher fail safe again.
Referring to Fig. 2, be electrical network capacitive current compensation circuit diagram disclosed in the utility model.As shown in Figure 2, this circuit comprises: the first three-phase reactor SK
1, compensation reactor LK
1And capacitor C
1
The said first three-phase reactor SK
1An end link to each other with power network line (three phase network); The neutral point of said first three-phase reactor connects said compensation reactor LK
1Said compensation reactor LK
1Any tap and said capacitor C
1Link to each other; Said capacitor C
1Another tap ground connection.
Need to prove, in the device disclosed in the utility model, can be in power network line (especially on the bus) parallelly connected a plurality of electrical network capacitive current compensation circuit.That is, when number of loads increases in the circuit, can increase the number of electrical network capacitive current compensation circuit.Concrete number can be confirmed according to actual conditions flexibly.In addition, the parameter of electrical network capacitive current compensation circuit (inductance value) can be regulated through tap.
In order to regulate the parameter of electrical network capacitive current compensation circuit better, disclosed device also comprises among the utility model Fig. 1: additional dc power supply module and peripheral circuit 105 thereof.
Concrete, referring to Fig. 3, be additional dc power supply module disclosed in the utility model and peripheral circuit diagram thereof.As shown in Figure 3, this circuit comprises: said peripheral circuit comprises: the second three-phase reactor SK
0With capacitance-resistance bleeder circuit LK
0
The said second three-phase reactor SK
0Connect said capacitance-resistance bleeder circuit LK
0Said capacitance-resistance bleeder circuit LK
0Connect additional dc power supply module (DY1); The said second three-phase reactor SK
0Neutral point connect said additional dc power supply module; The output DZ+ of said additional dc power supply module, DZ-link to each other with concentrating choosing leakage protector 101.
The function of additional dc power supply module and peripheral circuit 105 thereof is: the additional dc power supply module and the second three-phase reactor SK
0Form artificial neutral point; The additional dc power supply module provides a DC power supply; In order not change neutral grounding mode, the induction reactance of three-phase reactor is generally tens kilo-ohms, when there is electric leakage in system; Leakage network transformer secondary circuit constitutes the loop between reactor, DC power supply and the ground.According to Ohm's law; The size of direct current has directly been reacted electrical network insulation against ground level; The additional dc power supply module self has comparison circuit; When leak resistance is little when the operating value, DZ+, DZ-have fault-signal to export to the sequential identifying to concentrate choosing to leak protector, and the sequential identifying concentrates choosing to leak protector output action signal feed switch trip.
Referring to Fig. 4, be residual voltage sample circuit figure disclosed in the utility model.As shown in Figure 4, this circuit comprises: the second three-phase reactor SK
0, the first zero sequence transformer T
1With the second zero sequence transformer T
2
The said first zero sequence transformer T
1From the said second three-phase reactor SK
0Neutral point pick out, the secondary coil of said zero sequence transformer is imported the said second zero sequence transformer T
2, the said second zero sequence transformer T
2Secondary coil import said concentrated choosing and leak protector 101.
In the practical work process, if situation such as electric leakage take place power network line, the residual voltage sample circuit can be sampled and obtained residual voltage.Concentrate choosing to leak protector 101 and can make the earth leakage protective action based on sampled signal.
Referring to Fig. 5, be zero-sequence current sampling disclosed in the utility model and tripping operation control circuit figure.As shown in Figure 5, this circuit comprises: zero sequence current mutual inductor CT
1～CT
n
Zero sequence current mutual inductor CT
1～CT
n, place each minute feeding switch KB of power network line respectively
1～KB
nIn; The secondary side of zero sequence current mutual inductor leaks protector 101 through mining shielded type cable with said concentrated choosing and links to each other; The output of protector 101 is leaked in said concentrated choosing, and the separating brake of each vacuum circuit-breaker through total, the branch feeding switch in mining shielded type cable and the power network line is carried out point and linked to each other respectively.
In the practical work process, if situation such as electric leakage take place power network line, the zero-sequence current sample circuit can be sampled and obtained zero-sequence current.Concentrate choosing to leak protector 101 and can make the earth leakage protective action based on sampled signal.Concrete, when a certain branch road generation leaky, the separating brake of concentrating output that protector 101 is leaked in choosing can control the vacuum circuit-breaker of this branch road is carried out point and is broken off, thereby cuts off the power supply of this branch road.
In order can analysis result that concentrate choosing to leak protector to be shown, among Fig. 1, device disclosed in the utility model also comprises: leak the LCD MODULE 106 that protector links to each other with said concentrated choosing.
In order to show the operating state of each switch disconnector in the power network line, LCD MODULE 106 disclosed in the utility model also with power network line in the circuit breaker auxiliary contact of each feeding switch link to each other through lead.
Device disclosed in the utility model also comprises: the essential safe type buffer circuit and the essential safe type operation keyboard 107 that link to each other with said LCD MODULE 106.The setting of essential safe type operation keyboard 107 makes LCD MODULE 106 not only can initiatively show the operating state of each switch disconnector in the power network line, can also receive user's query statement, shows respective queries information according to user's needs.
Need to prove that the utility model adopts essential safe type buffer circuit and essential safe type operation keyboard.The energy of intrinsically safe circuit from restricting circuits started with; Potential spark energy is reduced to below the admixture of gas energy that can light regulation through reliable control circuit parameter, lead and assembly surface heating temp are limited under the ignition temperature of admixture of gas of regulation.
Device disclosed in the utility model also comprises: essential safe type keyboard division board; Instruction input keyboard 107 is connected to said essential safe type keyboard division board input side; Said essential safe type keyboard division board outlet side is connected to said LCD MODULE 106 through netting twine.
The housing that mine flameproof and intrinsic safety type disclosed in the utility model concentrates choosing to leak protective device is direct introduction-type blast resistance construction, and opening the door in front and back, is provided with explosion-proof turnover line horn mouth.This structural design can make concentrates the wiring operation of choosing leakage protective device easier to mine flameproof and intrinsic safety type, safety.
Each embodiment adopts the mode of going forward one by one to describe in this specification, and what each embodiment stressed all is and the difference of other embodiment that identical similar part is mutually referring to getting final product between each embodiment.
Used specific case herein the principle and the embodiment of the utility model are set forth, the explanation of above embodiment just is used to help to understand the method and the core concept thereof of the utility model; Simultaneously, for one of ordinary skill in the art, according to the thought of the utility model, part in specific embodiments and applications all can change.In sum, this description should not be construed as the restriction to the utility model.
Claims (10)
1. a mine flameproof and intrinsic safety type concentrates choosing to leak protective device, it is characterized in that, comprising: the sequential identifying concentrates choosing to leak protector, residual voltage sample circuit, zero-sequence current sampling and tripping operation control circuit, and electrical network capacitive current compensation circuit;
Said residual voltage sample circuit one end links to each other with power network line, and the other end leaks protector with said concentrated choosing and links to each other; One end of said zero-sequence current sampling and tripping operation control circuit links to each other with power network line, and the other end leaks protector with said concentrated choosing and links to each other; Said electrical network capacitive current compensation circuit is parallel to a side of power network line.
2. device according to claim 1 is characterized in that, said electrical network capacitive current compensation circuit comprises: first three-phase reactor, compensation reactor and electric capacity;
One end of said first three-phase reactor links to each other with three phase network; The neutral point of said first three-phase reactor connects said compensation reactor; Any tap of said compensation reactor links to each other with said electric capacity; Another tap ground connection of said electric capacity.
3. device according to claim 1 and 2 is characterized in that, also comprises: additional dc power supply module and peripheral circuit thereof;
Said peripheral circuit comprises: second three-phase reactor and capacitance-resistance bleeder circuit;
Said second three-phase reactor connects said capacitance-resistance bleeder circuit; Said capacitance-resistance bleeder circuit connects said additional dc power supply module; The neutral point of said second three-phase reactor connects said additional dc power supply module; The output of said additional dc power supply module leaks protector with said concentrated choosing and links to each other.
4. device according to claim 1 and 2 is characterized in that, said residual voltage sample circuit comprises: second three-phase reactor, the first zero sequence transformer and the second zero sequence transformer;
The said first zero sequence transformer picks out from the neutral point of said second three-phase reactor, and the secondary coil of the said first zero sequence transformer is imported the said second zero sequence transformer, and the secondary coil of the said second zero sequence transformer is imported said concentrated choosing and leaked protector.
5. device according to claim 1 and 2 is characterized in that, said zero-sequence current sampling and tripping operation control circuit comprise: zero sequence current mutual inductor;
Said zero sequence current mutual inductor, each minute that places power network line respectively is in the feeding switch; Said zero sequence current mutual inductor secondary side leak protector through mining shielded type cable and said concentrated choosing and link to each other; The protection action output of protector is leaked in said concentrated choosing, and the separating brake of each vacuum circuit-breaker through total, the branch feeding switch in mining shielded type cable and the power network line is carried out point and linked to each other respectively.
6. based on claim 1 or 2 described devices, it is characterized in that, also comprise: leak the LCD MODULE that protector links to each other with said concentrated choosing.
7. device according to claim 6 is characterized in that, the circuit breaker auxiliary contact of each feeding switch in said LCD MODULE and the power network line links to each other through lead.
8. device according to claim 6 is characterized in that, also comprises: essential safe type buffer circuit that links to each other with said LCD MODULE and essential safe type operation keyboard.
9. device according to claim 8 is characterized in that, also comprises: essential safe type keyboard division board; Said operation keyboard is connected to said essential safe type keyboard division board input side; Said essential safe type keyboard division board outlet side is connected to said LCD MODULE through netting twine.
10. device according to claim 1 is characterized in that, the housing that mine flameproof and intrinsic safety type concentrates choosing to leak protective device is direct introduction-type blast resistance construction, and opening the door in front and back, is provided with explosion-proof turnover line horn mouth.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011201297271U CN202121293U (en) | 2011-04-27 | 2011-04-27 | Mining flame-proof and essentially safe concentrated leakage selection protective device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011201297271U CN202121293U (en) | 2011-04-27 | 2011-04-27 | Mining flame-proof and essentially safe concentrated leakage selection protective device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202121293U true CN202121293U (en) | 2012-01-18 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011201297271U Expired - Fee Related CN202121293U (en) | 2011-04-27 | 2011-04-27 | Mining flame-proof and essentially safe concentrated leakage selection protective device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202121293U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014101656A1 (en) * | 2012-12-31 | 2014-07-03 | 中国矿业大学 | Method for monitoring insulation state of high-voltage power grid of coal mine |
| CN104753024A (en) * | 2015-03-18 | 2015-07-01 | 胡妍 | Electricity leakage protecting method for preventing symmetric electricity leakage |
-
2011
- 2011-04-27 CN CN2011201297271U patent/CN202121293U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014101656A1 (en) * | 2012-12-31 | 2014-07-03 | 中国矿业大学 | Method for monitoring insulation state of high-voltage power grid of coal mine |
| CN104753024A (en) * | 2015-03-18 | 2015-07-01 | 胡妍 | Electricity leakage protecting method for preventing symmetric electricity leakage |
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| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120118 Termination date: 20120427 |