CN2182482Y - Low-voltage selective electric leakage protecting device for mine use - Google Patents
Low-voltage selective electric leakage protecting device for mine use Download PDFInfo
- Publication number
- CN2182482Y CN2182482Y CN 94204091 CN94204091U CN2182482Y CN 2182482 Y CN2182482 Y CN 2182482Y CN 94204091 CN94204091 CN 94204091 CN 94204091 U CN94204091 U CN 94204091U CN 2182482 Y CN2182482 Y CN 2182482Y
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- control module
- main frame
- feeding switch
- binding post
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- Expired - Fee Related
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- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model relates to a low-voltage selective electric leakage protecting device for mines. The utility model is mainly composed of a host machine, a detecting control module and a zero sequence current transformer. The detecting control module is arranged in an electricity feeding switch connection box, the zero sequence current transformer is sheathed on a loading side three-phase wiring terminal arranged in the electricity feeding switch connection box, the existing electricity feeding switch is need to be refitted, and the flameproof box used for installing the zero sequence current transformer is not need to be additionally arranged on the utility model. The utility model has the advantages of high safety, small size, convenient installation, easy field maintenance, reliable performance, etc.
Description
The utility model is applicable to three-phase isolated neutral electric power system, cooperates electing property of feeding switch earth leakage protective.
At present, be the transmission of forceful electric power signal, complex structure, expense height, poor stability between selective low-voltage leakage protector for mine and the feeding switch; In addition, the mounting means of existing zero sequence current mutual inductor has two kinds: a kind of is that zero sequence current mutual inductor is installed on feeding switch inside, this need reequip former feeding switch, waste time and energy, its product quality depends on on-the-spot repacking workman's professional qualities to a great extent, to product quality can not be guaranteed fully; Though another kind is not reequiped former feeding switch, zero sequence current mutual inductor is installed in the outside of feeding switch, need additionally manufacture explosion-proof casing, production cost height, and the on-the-spot inconvenience of installing.
The purpose of this utility model is to design and a kind ofly realizes transmission and conversion between the strong and weak electricity with the detection control module, and former feeding switch is not done any repacking, does not also need additionally to increase the new type mining selective low-voltage leakage protector of explosion-proof casing.
The utility model is achieved in that
A kind of selective low-voltage leakage protector for mine is connected with feeding switch, is made up of main frame, detection control module and zero sequence current mutual inductor.Main frame is made up of supply line's insulation resistance prediction circuit, feeding switch working state signal treatment circuit, circuit measuring zero phase sequence current, phase-comparison circuit, signal latch circuit, zero sequence voltage detection circuit, phase-shift circuit, line insulation testing circuit, reserve timing circuit, insulating resistance value display circuit, backup protection executive circuit, signal display circuit, manual simulation's hookup, test circuit display circuit.Detecting control module is connected between main frame and the feeding switch.
Detect the control module surface five binding posts and a cable connector mouth are arranged.Wherein three meet 10 line terminals A, B, C are connected on respectively on the feeding switch load side three-phase binding post; A binding post is breaking coil binding post TQ, is connected on the feeding switch breaking coil binding post; A binding post is ground wire binding post N, is connected on the feeding switch ground terminal; A cable connector mouth is main frame cable connector mouth X1, links to each other with main frame by cable.
Detecting control module is the strong and weak electricity junction surface, is used to realize the transmission and the conversion of signal, helps security of products and reliability.Detecting control module is made up of feeding switch Working state checking circuit, electric leakage prediction channel control circuit, manual simulation's leak(age) test executive circuit and breaking coil drive circuit.The feeding switch Working state checking circuit is made up of photoelectronic coupler G1, G2, G3 and current-limiting resistance R1, R2, R3; Electric leakage prediction channel control circuit is by diode D1, D2, D3, D4, and current-limiting resistance R4 and relay J 1 are formed; Manual simulation's leak(age) test executive circuit is made up of test resistance R5 and relay J 2; The breaking coil drive circuit is made up of relay J 3.This detection control module is irritated the circuit board that mixes up when making with the poured with epoxy resin envelope, have characteristics such as little, the withstand voltage height of volume, humidity, shock resistance, therefore can directly place in the feeding switch terminal box.
Zero sequence current mutual inductor directly is enclosed within on the load side three-phase binding post of branch road feeding switch, and having overcome needs the shortcoming of explosion-proof casing is reequiped or additionally increased to feeding switch, thereby has reduced manufacturing cost, safe ready.
The interface of standard is all adopted in the connection at cable two ends, make when installing the school line and wiring work becomes simply, easily, accurately, reliably.
Major advantage of the present utility model is: simple in structure, cost is low, fail safe good, do not need former feeding switch is done any repacking, also not needing additionally increases explosion-proof casing, volume is little, easy for installation, on-site maintenance easily, action accurately and reliably.
Fig. 1, the outside connection layout of selective low-voltage leakage protector for mine
Fig. 2, host circuit board connection layout
Fig. 3, detection control module profile schematic diagram
Fig. 4, detection control module circuit theory diagrams
Fig. 5, zero sequence current mutual inductor
Fig. 6, cable connection diagram
Fig. 7, main frame front schematic view
Fig. 8, selective low-voltage leakage protector for mine theory diagram
Below in conjunction with accompanying drawing the utility model is described in further detail:
The utility model is made up of main frame 1, detection control module 2, zero sequence current mutual inductor 3 and cable 4, as shown in Figure 1.Main frame 1 with detect control module 2 and link to each other by cable 4, each binding post by detection control module surface between detection control module 2 and the feeding switch is connected.Zero sequence current mutual inductor 3 control module 2 after testing links to each other with main frame, also can directly link to each other with cable in addition with main frame, but the use amount that preceding a kind of connected mode can be saved cable.
With reference to Fig. 2, the circuit that the utility model is contained in the main frame is made up of 12 circuit, comprise: signal filtering trim panel 12, signal-processing board 13, shows signal drive plate 14, insulation resistance check-out console 15, simulation electric leakage circuit option board 16, feeding switch status signal disposable plates 17 and power panel 18, and with bus bar plate 21 between adopt female type to be connected.Be connected for lead between indicator panel 19, residual voltage phase shift plate 20, electronic filtering plate 22, signal cable interface board 23 and the bus bar plate 21.Main frame of the present utility model belongs to the prior art category, so do not do more description.
With reference to Fig. 3 and Fig. 4, detection control module of the present utility model surface has three binding post A, B, C to be connected on respectively on the feeding switch load side three-phase terminal post.Binding post TQ is the breaking coil binding post, is connected on the feeding switch breaking coil binding post.Binding post N is the ground wire binding post, is connected on the feeding switch ground terminal.Main frame cable connector mouth X1 links to each other with main frame by cable.Zero sequence current mutual inductor interface X2 links to each other with zero sequence current mutual inductor by cable.
Detecting control module is made up of feeding switch Working state checking circuit, electric leakage prediction channel control circuit, breaking coil drive circuit and manual simulation's leak(age) test executive circuit.
Feeding switch Working state checking circuit, its function are to detect feeding switch to be in "on" position or to be in the disjunction state, send testing result to main frame.This circuit is made up of photoelectronic coupler G1, G2, G3 and current-limiting resistance R1, R2, R3.Its connected mode is: the input 2 of three photoelectronic coupler G1, G2, G3 connects together, and input 1 is connected in series with current-limiting resistance R1, R2, R3 respectively, and links to each other with three binding post A, B, C detecting the control module surface.The emitter input 3 of three photoelectronic coupler G1, G2, G3 connects together, the output 4 of collector electrode connects together, and link to each other with 1,2 ends of the main frame cable connector mouth X1 that detects the control module surface respectively, it is linked to each other with the feeding switch status signal treatment circuit input port of main frame by cable.When feeding switch is in "on" position, the input of photoelectronic coupler G1, G2, G3 obtains AC signal, no matter this ac voltage signal is in positive half cycle or negative half period, as long as reach certain amplitude, the input of its photoelectronic coupler just has actuating signal output.When feeding switch is in the disjunction state, because of photoelectronic coupler G1, G2, G3 input no current flow through, so the output of the output attonity signal of photoelectronic coupler G1, G2, G3.
Pre-sorrowful channel control circuit leaks electricity: the function of this circuit is when feeding switch is in the disjunction state, and whether main control system is lower than setting to the detection of insulating of feeding switch load side supply line to judge its insulation.This circuit is made up of diode D1, D2, D3, D4, current-limiting resistance R4 and relay J 1.Three diode D1, D2, the anode of D3 connects together and links to each other with current-limiting resistance R4 polyphone and with the output 3 of relay J 1, three diode D1, D2, the negative electrode of D3 respectively with three binding post A that detect the control module surface, B, C links to each other, the anode of diode D4 links to each other with the ground wire binding post N that detects the control module surface, the negative electrode of diode D4 links to each other with another output 4 of relay J 1,4 ends with the main frame cable connector mouth X1 that detects the control module surface are connected simultaneously, making its supply line's insulation resistance prediction circuit by cable and main frame detect mouth links to each other, two inputs 1 of relay J 1 link to each other with 3 ends with 2 ends of the main frame cable connector mouth X1 that detects the control module surface respectively with 2, its supply line's insulation resistance prediction circuit and feeding switch load side supply line by cable and main frame is connected, supply line is carried out insulation resistance insulation prediction.After feeding switch closed a floodgate, relay J 1 disconnected two output because of input attonity signal, and the insulation resistance prediction of main frame supply line can not be carried out.The effect of diode D4 is to eliminate when feeding switch to close a floodgate moment and issuable interference under the situation that two outputs of relay do not have enough time to disconnect.
Manual simulation's leak(age) test executive circuit, the function of this circuit are to make test circuit that artificial electric leakage take place.This circuit is made up of test resistance R5 and relay J 2, the end of test resistance R5 links to each other with the ground wire binding post N that detects the control module surface, the other end links to each other with the output 3 of relay J 2, another output 4 of relay J 2 links to each other with the binding post C that detects the control module surface, two inputs of relay J 2 respectively with 5 of the main frame cable connector mouth X1 that detects the control module surface, 6 ends link to each other, when making its manual simulation's leak(age) test by cable and main frame, two inputs of relay J 2 obtain actuating signal, two output conducting, feeding switch load side supply line is connected with test resistance R5 through the output of binding post C and relay, has realized the requirement of manual simulation's electric leakage.
Breaking coil drive circuit, the function of this circuit are when the electric leakage accident takes place, and make the action of feeding switch tripping mechanism, feeding switch tripping operation outage.This circuit is realized by relay J 3.Two inputs 1 of relay J 3 link to each other with 7 ends with 2 ends of the main frame cable connector mouth X1 that detects the control module surface with 2, it is linked to each other with the signal latch circuit delivery outlet of main frame by cable, the output 3 of relay J 3 links to each other with the binding post C that detects the control module surface, and another output 4 links to each other with the breaking coil binding post TQ that detects the control module surface.When electrical network generation electric leakage accident, the input picked up signal of relay J 3, its output conducting is added on the binding post of feeding switch breaking coil an output and a breaking coil binding post TQ through relay J 3 of electrical network, make the action of feeding switch tripping mechanism, i.e. feeding switch tripping operation.The input attonity signal of relay J 3, its not conducting of output do not take place at electrical network under the situation of ground connection.
X1 among Fig. 4 is for detecting the nine core cable connector mouths that control module links to each other with main frame.X2 among Fig. 4 is the two core cable interface of zero sequence current mutual inductor, links to each other with zero sequence current mutual inductor by cable.1 end of zero sequence current mutual inductor cable connector mouth X2 links to each other with 9 ends through 8 ends of lead with main frame cable connector mouth X1 with 2 ends, and it is linked to each other with main frame with the shared cable of detection control module.Zero sequence current mutual inductor can be not yet control module and directly linking to each other with main frame after testing with cable.
1 end of main frame cable connector mouth X1 links to each other with the input port of 2 ends with the feeding switch status signal treatment circuit of main frame; 2 ends, 3 ends link to each other with the delivery outlet of the feeding switch status signal treatment circuit of main frame; 4 ends and main frame supply line insulation resistance prediction circuit detect and mouthful link to each other; 5 ends link to each other with manual simulation's leak(age) test circuit delivery outlet of main frame with 6 ends; 2 ends link to each other with the signal latch circuit delivery outlet of main frame with 7 ends; 8 ends link to each other with the zero sequence circuit signal testing circuit input port of main frame with 9 ends.
Four above-mentioned circuit all concentrate on the circuit board, irritate with the poured with epoxy resin envelope to form.
With reference to Fig. 5, zero sequence current mutual inductor 29 of the present utility model is sleeved on the load side three-phase binding post 31 in the feeding switch terminal box 30.Be used for detecting the zero-sequence current of its load side supply line.
With reference to Fig. 6, the signal cable that the utility model adopts is a shielded multiconductor cable 34, and standard interface 35 is adopted at its two ends, makes simple installation, saves time, reliably.
With reference to Fig. 7, main frame of the present utility model is a cylindrical body with flameproof enclosure, all electronic devices are installed in its inside, there are a signal cable terminal box 37 and power line terminal box 36 and base 38 in the outside, a circular flat of host housing is as host panel, and its panel arrangement is as follows:
Kilo-ohm table 5 shows power supply grid insulation against ground resistance value.8 dichromatic LEDs 6 are used as 1#～8# branch trouble and show: the red branch road leakage tripping of representing is indicated; Green this branch road feeding switch combined floodgate preload side line road insulation against ground resistance prediction leakage-current alarm of representing is indicated; After yellow was represented the branch road leakage tripping, fault was not removed the indication of reporting to the police yet.LED charactron 8 is used for showing current test circuit numbering: be neutral gear (the back initial condition powers on) when showing " 0 "; Show at 1～8 o'clock, represent the tested branch number of current manual simulation's leak(age) test respectively; When showing " 9 ", represent that current manual simulation's leak(age) test circuit is backup protection.Whenever press single test circuit selector button 9, then the demonstration numeral of charactron 8 increases the 1(carry and does not keep).Press manual simulation's leak(age) test button 10, then artificial leaky takes place, make this branch road feeding switch tripping mechanism action by charactron 8 indicated circuits, and the while light warning, carry out the test of manual simulation's leakage tripping.If press manual simulation's leak(age) test button 10 earlier, can carry out non-tripping operation manual simulation test.
With reference to Fig. 8, complete machine operation principle of the present utility model is as follows:
After system puts into operation, at first to the electrical network detection of insulating.Adopt the additional dc power supply principle, measure electrical network D.C. isolation resistance r over the ground
d, and directly show by a kilo-ohm table.Work as r
d＞R
dThe time, the reserve timer is not worked, and signal latch is forced to zero output.Leak electricity mutually when certain takes place electrical network, make r
d≤ R
dThe time, very big variation has all taken place in residual voltage signal and zero sequence current signal.Each branch road zero sequence current signal is sent into phase comparator after filtering, shaping, carry out bit comparison mutually with residual voltage signal after phase shift, shaping.After the phase bit comparison, its fault branch phase comparator has pulse signal output, but not the fault branch phase comparator then is always zero output.Signal latch is because of r
d≤ R
dAnd ring off signal is blocked, and fault branch phase comparator output signal directly is sent to its corresponding output end.Each output of signal latch is directly controlled the tripping mechanism drive circuit that each branch road detects control module, makes fault branch feeding switch tripping operation outage, and the leak current fault branch road is cut.
r
d≤ R
dMoment, the reserve timer just picks up counting.Work as r
d＞R
dThe time, reset the immediately zero clearing and remain zero output of reserve timer.Work as r
d≤ R
dHolding the time for the treatment of surpasses reserve timer setting time, and the breaking coil drive circuit that then is installed on the detection control module in the backup protection feeding switch terminal box obtains an actuating signal, makes backup protection feeding switch tripping operation outage.
After fault branch feeding switch tripping operation, its feeding switch state detection circuit that detects control module sends a reset signal, makes the zero clearing that resets immediately of signal latch and reserve timer.
When the branch road feeding switch did not close a floodgate, this branch road detected the electric leakage PREDICTIVE CONTROL circuit of control module and exports a working signal, and supply line's insulation resistance prediction circuit detects this branch road D.C. isolation resistance r over the ground
d'.Work as r
d' when being lower than setting, this tributary signal lamp shows green, light warning.
At any time, all can carry out manual simulation's leak(age) test, be tested circuit can freely select, show with the LED charactron by button.Manual simulation's leak(age) test is divided into the test of being failure to actuate of the action test of feeding switch tripping mechanism and feeding switch tripping mechanism.When carrying out manual simulation's leak(age) test, the work of manual simulation's leak(age) test executive circuit of its respective detection control module makes electric power system that artificial leaky take place, so that check whether this operating performance of plant is normal.
Claims (6)
1; a kind of selective low-voltage leakage protector for mine; be connected with feeding switch; constitute by main frame 1 and zero sequence current mutual inductor 3; main frame is by supply line's insulation resistance prediction circuit; feeding switch working state signal treatment circuit; circuit measuring zero phase sequence current; phase-comparison circuit; signal latch circuit; zero sequence voltage detection circuit; phase-shift circuit; the line insulation testing circuit; the reserve timing circuit; the insulating resistance value display circuit; the backup protection executive circuit; signal display circuit; manual simulation's hookup; the test circuit display circuit is formed, and it is characterized in that having a detection control module 2 to be connected between main frame 1 and the feeding switch.
2, a kind of selective low-voltage leakage protector for mine as claimed in claim 1 is characterized in that described detection control module 2 is made up of feeding switch Working state checking circuit, electric leakage prediction channel control circuit, breaking coil drive circuit and manual simulation's leak(age) test executive circuit;
The feeding switch Working state checking circuit is made up of photoelectronic coupler G1, G2, G3 and current-limiting resistance R1, R2, R3; Its connected mode is: the input 2 of three photoelectronic coupler G1, G2, G3 connects together, and input 1 is connected in series with current-limiting resistance R1, R2, R3 respectively, and links to each other with three binding post A, B, C detecting the control module surface; The emitter input 3 of three photoelectronic coupler G1, G2, G3 connects together, the output 4 of collector electrode connects together, and links to each other with 1,2 ends of the main frame cable connector mouth X1 that detects the control module surface respectively;
The pre-sorrowful channel control circuit that leaks electricity is made up of diode D1, D2, D3, D4, current-limiting resistance R4 and relay J 1; Three diode D1, D2, the anode of D3 connects together and links to each other with current-limiting resistance R4 polyphone and with the output 3 of relay J 1, three diode D1, D2, the negative electrode of D3 respectively with three binding post A that detect the control module surface, B, C links to each other, the anode of diode D4 links to each other with the ground wire binding post N that detects the control module surface, the negative electrode of diode D4 links to each other with another output 4 of relay J 1,4 ends with the main frame cable connector mouth X1 that detects the control module surface are connected simultaneously, and two inputs 1 of relay J 1 link to each other with 3 ends with 2 ends of the main frame cable connector mouth X1 that detects the control module surface respectively with 2;
Manual simulation's leak(age) test executive circuit is made up of test resistance R5 and relay J 2, the end of test resistance R5 links to each other with the ground wire binding post N that detects the control module surface, the other end links to each other with the output 3 of relay J 2, another output 4 of relay J 2 links to each other with the binding post C that detects the control module surface, and two inputs of relay J 2 link to each other with 5,6 ends of the main frame cable connector mouth X1 that detects the control module surface respectively;
The breaking coil drive circuit is realized by relay J 3, two inputs 1 of relay J 3 link to each other with 7 ends with 2 ends of the main frame cable connector mouth X1 that detects the control module surface with 2, the output 3 of relay J 3 links to each other with the binding post C that detects the control module surface, and another output 4 links to each other with the breaking coil binding post TQ that detects the control module surface;
Four above-mentioned circuit all concentrate on the circuit board, irritate with the poured with epoxy resin envelope to form;
Detecting control module 2 surfaces has five binding posts and a cable connector mouth, and wherein three binding post A, B, C are connected on respectively on the feeding switch load side three-phase terminal post; Binding post TQ is the breaking coil binding post, is connected on the feeding switch breaking coil binding post; Binding post N is the ground wire binding post, is connected on the feeding switch ground terminal; Cable connector mouth X1 is that nine core cable connector mouths link to each other with main frame; 1 end of main frame cable connector mouth X1 links to each other with the input port of 2 ends with the feeding switch status signal treatment circuit of main frame, 2 ends, 3 ends link to each other with the delivery outlet of the feeding switch status signal treatment circuit of main frame, and 4 ends and main frame supply line insulation resistance prediction circuit detect and mouthful link to each other; 5 ends link to each other with manual simulation's leak(age) test circuit delivery outlet of main frame with 6 ends, and 2 ends link to each other with the signal latch circuit delivery outlet of main frame with 7 ends.
3, a kind of selective low-voltage leakage protector for mine according to claim 2, it is characterized in that there is a zero sequence current mutual inductor cable connector mouth X2 on described detection control module surface, 1 end of X2 links to each other with 9 ends with 8 ends of main frame cable connector mouth X1 respectively with 2 ends; A cable connector mouth 32 is also arranged on the described zero sequence current mutual inductor, link to each other with the zero sequence current mutual inductor cable connector mouth X2 that detects the control module surface by cable.
4,, it is characterized in that described detection control module places in the feeding switch terminal box according to claim 1,2,3 described a kind of selective low-voltage leakage protector for mine.
5,, it is characterized in that described zero sequence current mutual inductor is enclosed within on the branch road feeding switch terminal box internal loading side three-phase binding post 31 according to claim 1,2,3 described a kind of selective low-voltage leakage protector for mine.
6, a kind of selective low-voltage leakage protector for mine according to claim 4 is characterized in that described zero sequence current mutual inductor is enclosed within on the branch road feeding switch terminal box internal loading side three-phase binding post 31.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 94204091 CN2182482Y (en) | 1994-03-04 | 1994-03-04 | Low-voltage selective electric leakage protecting device for mine use |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 94204091 CN2182482Y (en) | 1994-03-04 | 1994-03-04 | Low-voltage selective electric leakage protecting device for mine use |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2182482Y true CN2182482Y (en) | 1994-11-09 |
Family
ID=33823426
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 94204091 Expired - Fee Related CN2182482Y (en) | 1994-03-04 | 1994-03-04 | Low-voltage selective electric leakage protecting device for mine use |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2182482Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102419407A (en) * | 2011-08-18 | 2012-04-18 | 山东科技大学 | Ground detection experiment system for mining equipment |
-
1994
- 1994-03-04 CN CN 94204091 patent/CN2182482Y/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102419407A (en) * | 2011-08-18 | 2012-04-18 | 山东科技大学 | Ground detection experiment system for mining equipment |
| CN102419407B (en) * | 2011-08-18 | 2013-07-24 | 山东科技大学 | Ground detection experiment system for mining equipment |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |