CN203572909U - Single-phase ground fault detection circuit and system - Google Patents
Single-phase ground fault detection circuit and system Download PDFInfo
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- CN203572909U CN203572909U CN201320744443.2U CN201320744443U CN203572909U CN 203572909 U CN203572909 U CN 203572909U CN 201320744443 U CN201320744443 U CN 201320744443U CN 203572909 U CN203572909 U CN 203572909U
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Abstract
The utility model provides a single-phase ground fault detection circuit. The single-phase ground fault detection circuit comprises an alarm circuit, a voltage sensor, a voltage comparison circuit and a timing circuit, wherein the voltage sensor acquires the voltage value of a connecting row between a transformer and a transition contact; when the voltage value acquired by the voltage sensor is above a preset voltage value, a first control signal is outputted to the timing circuit, and the timing circuit generates a second control signal to control an alarm in the alarm circuit to give an alarm before the preset time is up so that early warning for single-phase ground faults is effectively performed, and the safety of a power supply system is guaranteed.
Description
Technical field
The utility model relates to power failure detection technique field, relates in particular a kind of phase-to-ground fault detection circuit and system.
Background technology
Along with socioeconomic development, the raising day by day of electrified level, the consumption of electric energy is also increasing.Conventionally, China's power distribution network adopts the not directly grounded mode of neutral point to carry out the transmission of electric energy, and which is also referred to as small current neutral grounding power supply mode.
At present, affected by mains supply load etc., the frequent long period of main transformer 35kV switch of main-transformer in 110kV transformer station (Yi Sanquan becomes example) is in hot stand-by duty, formed main transformer 110kV side and only supply the special method of operation of 10kV.
Inventor's discovery, under the above-mentioned method of operation, main transformer medium voltage side sleeve pipe to the link cable between 35kV transition contact cabinet easily punctures, and then causes the fault of main transformer differential protection action tripping operation.Concrete, when the not directly grounded mode of this neutral point is powered, if there is single-phase earthing in operational process, operations staff can not find in time.Although 35kV system is isolated neutral system, allow single-phase earthing operation a period of time, but system insulation is very fragile under single-phase earthing mode, if be subject to disturbance or the defective insulation of cable own of some electrical networks, very likely develop into 2 earth faults, make electric power system superpotential, thereby make the short circuit of main transformer near zone, there is power failure phenomenon, and affect the safety of electric power system.
Visible, under the above-mentioned method of operation, a kind of phase-to-ground fault detection device is provided, it is considerable to voltage, detecting with early warning, it can inform in the very first time operating mode of operating personnel's cable (or busbar), once generation singlephase earth fault, can take the precautionary measures in time, avoid the expansion of accident and have a power failure on a large scale.
Utility model content
In view of this, the utility model provides a kind of phase-to-ground fault detection circuit, effectively singlephase earth fault is carried out to early warning, has ensured the safety of electric power system.
For achieving the above object, the utility model provides following technical scheme:
A kind of phase-to-ground fault detection circuit, comprising:
Warning circuit, described warning circuit at least comprises alarm;
Gather the voltage sensor that is connected the magnitude of voltage on row between transformer and transition contact;
Be connected with described voltage sensor, when the magnitude of voltage collecting when described voltage sensor is greater than predeterminated voltage value, the voltage comparator circuit of output the first control signal;
Be connected with described voltage comparator circuit, receive described the first control signal, when Preset Time arrives, produce the timing circuit of alarm equipment alarm described in the second control signal control.
Preferably, also comprise:
Be arranged between described voltage comparator circuit and described timing circuit the pilot lamp of lighting when described voltage comparator circuit is exported described the first control signal.
Preferably, described voltage sensor at least comprises:
Be serially connected in the first electric capacity between signal output part and the ground of described transformer.
Preferably, described voltage sensor comprises: voltage dependent resistor (VDR), current-limiting resistance, decoupling capacitor, the first commutation diode, the second commutation diode, stabilivolt, filter capacitor and shunt resistance;
The first end of described voltage dependent resistor (VDR) is connected with the first end of described current-limiting resistance and as the input end of described voltage sensor, the second end of described current-limiting resistance respectively with the first end of described decoupling capacitor, the negative electrode of the anode of described the first commutation diode and described the second commutation diode is connected, the negative electrode of described the first commutation diode respectively with the negative electrode of described stabilivolt, the first end of described filter capacitor and the first end of described shunt resistance are connected and as the output terminal of described voltage sensor, the second end of described voltage dependent resistor (VDR), the second end of described decoupling capacitor, the anode of described the first commutation diode, the anode of described stabilivolt, the equal ground connection of the second end of the second end of described filter capacitor and described shunt resistance.
Preferably, also comprise:
Be arranged on the photoelectrical coupler between described voltage comparator circuit and described timing circuit;
The input end of described photoelectrical coupler is serially connected between the output terminal and ground of described voltage comparator circuit, and the output terminal of described photoelectrical coupler is connected with the input end of described timing circuit.
Preferably, described timing circuit comprises: supplying resistance, delay capacitor, the first divider resistance, the second divider resistance, the first voltage stabilizing diode and operational amplifier;
The first end of described supplying resistance is respectively with the first end of described the first divider resistance and the negative electrode of described the first voltage stabilizing diode is connected and as the first output terminal of described timing circuit, the second end of described supplying resistance is connected with the first output terminal of described photoelectrical coupler, the second end of described the first divider resistance is connected with the inverting input of described operational amplifier and the first end of described the second divider resistance respectively, the second output terminal of described photoelectrical coupler is connected with the first end of described delay capacitor and the in-phase input end of described operational amplifier respectively, the second end of described delay capacitor, the equal ground connection of negative electrode of the second end of described the second divider resistance and described the first stabilivolt and as the second output terminal of described timing circuit, the output terminal of described operational amplifier is as the signal output part of described timing circuit.
Preferably, described warning circuit comprises: relay, switching tube and alarm;
The control end of described switching tube is connected with the signal output part of described timing circuit, the coil tandem of described relay is between the input end of described switching tube and the first output terminal of described timing module, the output head grounding of described switching tube, the normal open switch of described relay is connected with described alarm.
Preferably, described predeterminated voltage value is 1.2 times of specified phase voltage on described connection row, and described Preset Time is two minutes.
Preferably, also comprise:
Be connected with the signal output part of described timing circuit, receiving after described the second control signal, send the GSM transceiver module of warning message.
A kind of phase-to-ground fault detection system, is characterized in that, comprises remote monitoring platform and phase-to-ground fault detection circuit as above-mentioned in any one.
Known via above-mentioned technical scheme, compared with prior art, the utility model provides a kind of phase-to-ground fault detection circuit, comprising: warning circuit, voltage sensor, voltage comparator circuit and timing circuit.Wherein, voltage sensor gathers the magnitude of voltage on row that is connected between transformer and transition contact, when the magnitude of voltage collecting when voltage sensor is greater than predeterminated voltage value, output first controls signal to timing circuit, when Preset Time arrives, the alarm that this timing circuit produces in the second control signal control warning circuit sends warning.Effectively singlephase earth fault is carried out to early warning, ensured the safety of electric power system.
Accompanying drawing explanation
In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only embodiment of the present utility model, for those of ordinary skills, do not paying under the prerequisite of creative work, other accompanying drawing can also be provided according to the accompanying drawing providing.
The theory diagram of a kind of phase-to-ground fault detection circuit that Fig. 1 provides for the utility model;
The principle schematic of a kind of phase-to-ground fault detection circuit that Fig. 2 provides for the utility model;
The principle schematic of another phase-to-ground fault detection circuit that Fig. 3 provides for the utility model;
The physical circuit figure of a kind of phase-to-ground fault detection circuit that Fig. 4 provides for the utility model.
Embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the utility model embodiment is clearly and completely described, obviously, described embodiment is only 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 obtaining under creative work prerequisite, all belong to the scope of the utility model protection.
Refer to Fig. 1, the theory diagram of a kind of phase-to-ground fault detection circuit providing for the utility model, this phase-to-ground fault detection circuit, comprise: voltage sensor 101, voltage comparator circuit 102, timing circuit 103 and warning circuit 104, wherein, warning circuit 104 comprises alarm 1041.
Wherein, voltage sensor 101 is for gathering the magnitude of voltage on row that is connected between transformer and transition contact.Voltage comparator circuit is connected with voltage sensor, the magnitude of voltage that receiver voltage sensor collects, and this magnitude of voltage receiving and predeterminated voltage value are compared, when the magnitude of voltage collecting is greater than predeterminated voltage value, output first controls signal to timing circuit.When Preset Time arrives, the alarm that timing circuit produces in the second control signal control warning circuit is reported to the police.
Visible, the utility model provides a kind of phase-to-ground fault detection circuit, effectively singlephase earth fault is carried out to early warning, has ensured the safety of electric power system.
Preferably, the utility model also provides a kind of principle schematic of single-phase fault testing circuit, and as shown in Figure 2, this testing circuit comprises: voltage sensor 101, voltage comparator circuit 102, timing circuit 103 and warning circuit 104, wherein, warning circuit 104 comprises alarm.From the figure not difficult to find, this warning circuit 104 comprises: relay 1042, switching tube and alarm.
Wherein, the annexation of each device is: the control end of switching tube is connected with the signal output part of timing circuit, the coil tandem of relay between the input end of switching tube and the first output terminal of timing module, the output head grounding of switching tube, the normal open switch of relay is connected with alarm.
In conjunction with the concrete structure of this warning circuit, the principle of work of the single-phase fault testing circuit that this embodiment provides is:
Adopt the utility model that a kind of phase-to-ground fault detection circuit is provided, can effectively to singlephase earth fault, carry out early warning, ensured the safety of electric power system.
Preferably, in conjunction with actual conditions, the present embodiment gives the optimal case of predeterminated voltage value and Preset Time, and if definition predeterminated voltage value is to connect 1.2 times of specified phase voltage on row, Preset Time is two minutes etc.It should be noted that, restriction herein, just in order to illustrate, is not confined to this by the application's protection domain.Preset Time herein and predeterminated voltage can be by realizing the change of voltage comparator circuit 102 and timing circuit 103.
In order better to carry out early warning, as shown in Figure 3, the present embodiment is also provided with pilot lamp 105 between voltage comparator circuit 102 and timing circuit 103.This pilot lamp 105 is lighted when voltage comparator circuit 102 is exported the first control signal.Also,, when the voltage detecting is during higher than 1.2 times of single-phase rated voltage, pilot lamp is lighted.Except this, the present embodiment is also provided with photoelectrical coupler 106 between voltage comparator circuit 102 and timing circuit 103.The input end of this photoelectrical coupler is serially connected between the output terminal and ground of voltage comparator circuit, and its output terminal is connected with the input end of timing circuit.
Concrete, the present embodiment also provides a kind of specific implementation circuit of phase-to-ground fault detection circuit, and as shown in Figure 4, wherein, this testing circuit comprises: voltage sensor, voltage comparator circuit, timing circuit and warning circuit.
Wherein, voltage sensor at least comprises the first electric capacity between signal output part and the ground that is serially connected in transformer.By this electric capacity, realize the maintenance collection to voltage.Concrete, voltage sensor comprises: voltage dependent resistor (VDR), current-limiting resistance, decoupling capacitor, the first commutation diode, the second commutation diode, stabilivolt, filter capacitor and shunt resistance.
Its annexation is:
The first end of voltage dependent resistor (VDR) is connected with the first end of current-limiting resistance and as the input end of voltage sensor, the second end of current-limiting resistance respectively with the first end of decoupling capacitor, the negative electrode of the anode of the first commutation diode and the second commutation diode is connected, the negative electrode of the first commutation diode respectively with the negative electrode of stabilivolt, the first end of filter capacitor and the first end of shunt resistance are connected and as the output terminal of voltage sensor, the second end of voltage dependent resistor (VDR), the second end of decoupling capacitor, the anode of the first commutation diode, the anode of stabilivolt, the equal ground connection of the second end of the second end of filter capacitor and shunt resistance.
Timing circuit comprises: supplying resistance, delay capacitor, the first divider resistance, the second divider resistance, the first voltage stabilizing diode and operational amplifier;
The first end of supplying resistance is respectively with the first end of the first divider resistance and the negative electrode of the first voltage stabilizing diode is connected and as the first output terminal of timing circuit, the second end of supplying resistance is connected with the first output terminal of photoelectrical coupler, the second end of the first divider resistance is connected with the inverting input of operational amplifier and the first end of the second divider resistance respectively, the second output terminal of photoelectrical coupler is connected with the first end of delay capacitor and the in-phase input end of operational amplifier respectively, the second end of delay capacitor, the equal ground connection of negative electrode of the second end of the second divider resistance and the first stabilivolt and as the second output terminal of timing circuit, the output terminal of operational amplifier is as the signal output part of timing circuit.
In conjunction with above-mentioned concrete annexation, the principle of work of this phase-to-ground fault detection circuit is:
Voltage dependent resistor (VDR) f1 and voltage stabilizing diode DW1 carry out overvoltage protection, by current-limiting resistance R1, decoupling capacitor C1 are charged, and gather the process of voltage, in this circuit, have increased commutation diode D1 and D2, for making electric current steady.Filter capacitor C4 is that the voltage to gathering carries out filtering processing, and resistance R 4 is the values for regulating starter valve.After this, by the input end of the voltage signal input comparator U1 collecting, when the input voltage of comparer U1 is greater than preset value, output the first control signal, makes LED 1 and photoelectrical coupler U4 conducting.
Then the output signal of photoelectrical coupler U4 is given delay capacitor C7 charging through resistance R 10, it should be noted that herein, the capacity that different electric capacity are set can determine the time of time delay, enough when electric when being filled with in capacitor C 7, when now the voltage of the in-phase input end of comparer is higher than the voltage of inverting input, comparer output second controls signal to switching tube Q1, and Q1 conducting makes the actuating of relay, and alarm sends warning.
In conjunction with foregoing circuit annexation, be not difficult to find, the phase-to-ground fault detection device that the present embodiment provides is the transmission that adopts switching value signal, compared to the direct transmission of voltage or electric current, can effectively avoid the voltage deformity of voltage or current delivery existence and the phenomenon of distortion, transfer efficiency is high.
Preferably, short message transceiving module can also be set, receive after described the second control signal, send mobile phone or the remote console of warning message to operating personnel, so that the fault to on-the-spot of operating personnel's energy timing is processed.
It should be noted that, a kind of phase-to-ground fault detection device that the present embodiment provides also possesses charged display device, and this charged display device is identical with the 26S Proteasome Structure and Function of the charged display device on switch cabinet panel in prior art.Under main transformer normal operating condition, bus single-phase earthing is pressed to become by bus and is detected and alarm, and this phase-to-ground fault detection device is not worked.When main transformer switch disconnects, main transformer is to the bus generation single-phase earthing between main transformer switch, and now, the work of this phase-to-ground fault detection device, effectively carries out early warning to singlephase earth fault, has ensured the safety of electric power system.
In addition to the implementation, the utility model also provides a kind of phase-to-ground fault detection system, comprises remote monitoring platform and phase-to-ground fault detection circuit as above-mentioned in any one.Principle of work and the structure of its testing circuit refer to above-described embodiment, again do not describe in detail.
To sum up, the utility model provides a kind of phase-to-ground fault detection circuit, comprising: warning circuit, voltage sensor, voltage comparator circuit and timing circuit.Wherein, voltage sensor gathers the magnitude of voltage on row that is connected between transformer and transition contact, when the magnitude of voltage collecting when voltage sensor is greater than predeterminated voltage value, output first controls signal to timing circuit, when Preset Time arrives, the alarm that this timing circuit produces in the second control signal control warning circuit sends warning.Effectively singlephase earth fault is carried out to early warning, ensured the safety of electric power system.
In this instructions, each embodiment adopts the mode of going forward one by one to describe, and each embodiment stresses is and the difference of other embodiment, between each embodiment identical similar part mutually referring to.For the device providing for embodiment, because its method providing with embodiment is corresponding, so description is fairly simple, relevant part illustrates referring to method part.
To the above-mentioned explanation of provided embodiment, make professional and technical personnel in the field can realize or use the utility model.To the multiple modification of these embodiment, will be apparent for those skilled in the art, General Principle as defined herein can, in the situation that not departing from spirit or scope of the present utility model, realize in other embodiments.Therefore, the utility model will can not be restricted to these embodiment shown in this article, but will meet the widest scope consistent with principle provided in this article and features of novelty.
Claims (10)
1. a phase-to-ground fault detection circuit, is characterized in that, comprising:
Warning circuit, described warning circuit at least comprises alarm;
Gather the voltage sensor that is connected the magnitude of voltage on row between transformer and transition contact;
Be connected with described voltage sensor, when the magnitude of voltage collecting when described voltage sensor is greater than predeterminated voltage value, the voltage comparator circuit of output the first control signal;
Be connected with described voltage comparator circuit, receive described the first control signal, when Preset Time arrives, produce the timing circuit of alarm equipment alarm described in the second control signal control.
2. phase-to-ground fault detection circuit according to claim 1, is characterized in that, also comprises:
Be arranged between described voltage comparator circuit and described timing circuit the pilot lamp of lighting when described voltage comparator circuit is exported described the first control signal.
3. phase-to-ground fault detection circuit according to claim 1, is characterized in that, described voltage sensor at least comprises:
Be serially connected in the first electric capacity between signal output part and the ground of described transformer.
4. phase-to-ground fault detection circuit according to claim 1, it is characterized in that, described voltage sensor comprises: voltage dependent resistor (VDR), current-limiting resistance, decoupling capacitor, the first commutation diode, the second commutation diode, stabilivolt, filter capacitor and shunt resistance;
The first end of described voltage dependent resistor (VDR) is connected with the first end of described current-limiting resistance and as the input end of described voltage sensor, the second end of described current-limiting resistance respectively with the first end of described decoupling capacitor, the negative electrode of the anode of described the first commutation diode and described the second commutation diode is connected, the negative electrode of described the first commutation diode respectively with the negative electrode of described stabilivolt, the first end of described filter capacitor and the first end of described shunt resistance are connected and as the output terminal of described voltage sensor, the second end of described voltage dependent resistor (VDR), the second end of described decoupling capacitor, the anode of described the first commutation diode, the anode of described stabilivolt, the equal ground connection of the second end of the second end of described filter capacitor and described shunt resistance.
5. phase-to-ground fault detection circuit according to claim 1, is characterized in that, also comprises:
Be arranged on the photoelectrical coupler between described voltage comparator circuit and described timing circuit;
The input end of described photoelectrical coupler is serially connected between the output terminal and ground of described voltage comparator circuit, and the output terminal of described photoelectrical coupler is connected with the input end of described timing circuit.
6. phase-to-ground fault detection circuit according to claim 5, is characterized in that, described timing circuit comprises: supplying resistance, delay capacitor, the first divider resistance, the second divider resistance, the first voltage stabilizing diode and operational amplifier;
The first end of described supplying resistance is respectively with the first end of described the first divider resistance and the negative electrode of described the first voltage stabilizing diode is connected and as the first output terminal of described timing circuit, the second end of described supplying resistance is connected with the first output terminal of described photoelectrical coupler, the second end of described the first divider resistance is connected with the inverting input of described operational amplifier and the first end of described the second divider resistance respectively, the second output terminal of described photoelectrical coupler is connected with the first end of described delay capacitor and the in-phase input end of described operational amplifier respectively, the second end of described delay capacitor, the equal ground connection of negative electrode of the second end of described the second divider resistance and described the first stabilivolt and as the second output terminal of described timing circuit, the output terminal of described operational amplifier is as the signal output part of described timing circuit.
7. phase-to-ground fault detection circuit according to claim 5, is characterized in that, described warning circuit comprises: relay, switching tube and alarm;
The control end of described switching tube is connected with the signal output part of described timing circuit, the coil tandem of described relay is between the input end of described switching tube and the first output terminal of described timing module, the output head grounding of described switching tube, the normal open switch of described relay is connected with described alarm.
8. phase-to-ground fault detection circuit according to claim 1, is characterized in that, described predeterminated voltage value is 1.2 times of specified phase voltage on described connection row, and described Preset Time is two minutes.
9. phase-to-ground fault detection circuit according to claim 1, is characterized in that, also comprises:
Be connected with the signal output part of described timing circuit, receiving after described the second control signal, send the GSM transceiver module of warning message.
10. a phase-to-ground fault detection system, is characterized in that, comprises remote monitoring platform and the phase-to-ground fault detection circuit as described in any one in claim 1-9.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320744443.2U CN203572909U (en) | 2013-11-21 | 2013-11-21 | Single-phase ground fault detection circuit and system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201320744443.2U CN203572909U (en) | 2013-11-21 | 2013-11-21 | Single-phase ground fault detection circuit and system |
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| CN203572909U true CN203572909U (en) | 2014-04-30 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103558502A (en) * | 2013-11-21 | 2014-02-05 | 国家电网公司 | Single-phase earth fault detection circuit, method and system |
| CN104009753A (en) * | 2014-06-03 | 2014-08-27 | 深圳市大族激光科技股份有限公司 | Alarming signal display and level isolation circuit and application thereof |
| CN107656167A (en) * | 2017-10-31 | 2018-02-02 | 国网江苏省电力公司南通供电公司 | Singlephase earth fault alarm detecting device |
| CN110824380A (en) * | 2019-11-06 | 2020-02-21 | 科华恒盛股份有限公司 | Three-phase earth fault detection circuit and three-phase earth fault detection method |
| CN112824842A (en) * | 2019-11-21 | 2021-05-21 | 浙江三花制冷集团有限公司 | Acquisition circuit and pressure sensor classification method |
| CN113917219A (en) * | 2021-10-08 | 2022-01-11 | 广东电网有限责任公司东莞供电局 | Automatic detection alarm device |
-
2013
- 2013-11-21 CN CN201320744443.2U patent/CN203572909U/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103558502A (en) * | 2013-11-21 | 2014-02-05 | 国家电网公司 | Single-phase earth fault detection circuit, method and system |
| CN103558502B (en) * | 2013-11-21 | 2017-05-24 | 国家电网公司 | Single-phase earth fault detection circuit, method and system |
| CN104009753A (en) * | 2014-06-03 | 2014-08-27 | 深圳市大族激光科技股份有限公司 | Alarming signal display and level isolation circuit and application thereof |
| CN107656167A (en) * | 2017-10-31 | 2018-02-02 | 国网江苏省电力公司南通供电公司 | Singlephase earth fault alarm detecting device |
| CN110824380A (en) * | 2019-11-06 | 2020-02-21 | 科华恒盛股份有限公司 | Three-phase earth fault detection circuit and three-phase earth fault detection method |
| CN112824842A (en) * | 2019-11-21 | 2021-05-21 | 浙江三花制冷集团有限公司 | Acquisition circuit and pressure sensor classification method |
| CN113917219A (en) * | 2021-10-08 | 2022-01-11 | 广东电网有限责任公司东莞供电局 | Automatic detection alarm device |
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