CN203811695U - Three-phase four-wire system fiber detection open-phase and power-off alarm device - Google Patents
Three-phase four-wire system fiber detection open-phase and power-off alarm device Download PDFInfo
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- CN203811695U CN203811695U CN201420134935.4U CN201420134935U CN203811695U CN 203811695 U CN203811695 U CN 203811695U CN 201420134935 U CN201420134935 U CN 201420134935U CN 203811695 U CN203811695 U CN 203811695U
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Abstract
Three-phase four-wire system fiber detection open-phase and power-off alarm device. The device comprises an A-phase detection circuit, a B-phase detection circuit and a C-phase detection circuit, wherein the above detection circuits comprise similar components. The head ends of the detection circuits are respectively connected to an A phase, a B phase and a C phase, or connected to an equivalent circuit output ports for detecting the phase lines of the A, B and C three-phase power supply ( i.e. a three-phase output port after conversion of a voltage transformer). The tail ends of the detection circuits are connected together to form a Y shape. The alarm device can detect the open phase power supply of a three-phase power supply and determine whether the three-phase power supply is powered off or not. Since the alarm device utilizes the photoelectric isolation detection mode, so as to overcome the defects of the conventional detection device. The alarm device is advantaged by being simple in design, reasonable in structure, small in size, and easy to produce, and makes great improvements in reliability, safety, remote transmission characteristics, interference immunity, versatility, real-time performance and maintenance cost.
Description
Technical field
The utility model belongs to the protection alarm field of low-voltage distribution and consumer, in particular, relates to phase shortage and power failure alarm device that a kind of three-phase four-wire system optical fiber detects.
Background technology
Low-voltage distribution and consumer adopt three-phase four-wire system more, in the middle of operation, are subject to natural, artificial and impact other unexpected event, and phase shortage is more common phenomenon of the failure.If find not in time and process, bring immeasurable loss likely can to safety and the economical operation of low-voltage distribution and consumer, directly can affect the normal production of people and life.And tradition is for detection of the device of phase shortage, the devices that adopt mutual inductor bulky and that power consumption is not weak or relay and so on more, not only detection signal response speed is slow, long-distance transmissions characteristic is strong, a little less than anti-interference, and versatility is strong, real-time is poor, maintenance cost is higher.
Summary of the invention
In view of this, the utility model aims to provide phase shortage and the power failure alarm device that a kind of three-phase four-wire system optical fiber detects, can detect and lack the whether power-off of which phase power supply and three-phase supply in the middle of three-phase supply, not only overcome the defect of traditional detection device deficiency, there is simplicity of design, rational in infrastructure, volume is little, be easy to the outstanding advantages produced, and improved significantly at aspects such as reliability, security, long-distance transmissions characteristic, anti-interference, versatility, real-time and maintenance costs.
The technical solution of the utility model is:
The phase shortage and the power failure alarm device that provide a kind of three-phase four-wire system optical fiber to detect, is characterized in that:
Comprise A phase detecting circuit, B phase detecting circuit and C phase detecting circuit, every testing circuit is made up of similar device, the head end of every testing circuit is received respectively in the phase line of A, B and C three-phase supply, or receive respectively on the equivalent electrical circuit delivery outlet (such as the three-phase delivery outlet after voltage transformer (VT) conversion) that detects A, B and C three-phase supply phase line, the tail end of every testing circuit is connected together, form Y connection, its common node is connected on center line N;
Described A phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R a1, resistance R a2 is composed in series, its one end is connected on A phase power supply, electricity is by diode Da1 with light signal change-over circuit, diode Da2, diode Da3, diode Da4, capacitor C a1, resistance R a3, voltage stabilizing diode Dza1, resistance R a4 and optical fiber launching seat HFa composition, wherein, diode Da1, diode Da2, diode Da3 and diode Da4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C a1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R a3 and voltage stabilizing diode Dza1, further, between the negative electrode of voltage stabilizing diode Dza1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Ra4 and optical fiber launching seat HFa, wherein, one end of the anode connecting resistance Ra4 of optical fiber launching seat HFa, the negative electrode of optical fiber launching seat HFa connects the anode of voltage stabilizing diode Dza1,
Described B phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R b1, resistance R b2 is composed in series, its one end is connected on B phase power supply, electricity is by diode Db1 with light signal change-over circuit, diode Db2, diode Db3, diode Db4, capacitor C b1, resistance R b3, voltage stabilizing diode Dzb1, resistance R b4 and optical fiber launching seat HFb composition, wherein, diode Db1, diode Db2, diode Db3 and diode Db4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C b1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R b3 and voltage stabilizing diode Dzb1, further, between the negative electrode of voltage stabilizing diode Dzb1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Rb4 and optical fiber launching seat HFb, wherein, one end of the anode connecting resistance Rb4 of optical fiber launching seat HFb, the negative electrode of optical fiber launching seat HFb connects the anode of voltage stabilizing diode Dzb1,
Described C phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R c1, resistance R c2 is composed in series, its one end is connected on C phase power supply, electricity is by diode Dc1 with light signal change-over circuit, diode Dc2, diode Dc3, diode Dc4, capacitor C c1, resistance R c3, voltage stabilizing diode Dzc1, resistance R c4 and optical fiber launching seat HFc composition, wherein, diode Dc1, diode Dc2, diode Dc3 and diode Dc4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C c1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R c3 and voltage stabilizing diode Dzc1, further, between the negative electrode of voltage stabilizing diode Dzc1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Rc4 and optical fiber launching seat HFc, wherein, one end of the anode connecting resistance Rc4 of optical fiber launching seat HFc, the negative electrode of optical fiber launching seat HFc connects the anode of voltage stabilizing diode Dzc1,
Each phase detecting circuit in the middle of described A phase detecting circuit, B phase detecting circuit and C phase detecting circuit is that the electric signal of place phase is converted to after light signal, carry out remote signal conveying by corresponding electricity and light conversion branch road again, central arbitrary phase detecting circuit is while can't detect photosignal, after logic judgement, think this phase power phase shortage, if all can't detect photosignal, after logic judgement, think that three-phase supply is power-off.
The beneficial effects of the utility model are, the phase shortage and the power failure alarm device that provide three-phase four-wire system optical fiber to detect, adopt the detection mode of photoelectricity isolation, can detect and lack the whether power-off of which phase power supply and three-phase supply in the middle of three-phase supply, not only overcome the defect of traditional detection device deficiency, there is simplicity of design, rational in infrastructure, volume is little, be easy to the outstanding advantages produced, and improved significantly aspect the real-time of reliability, versatility, security and detection.
Brief description of the drawings
In order to be illustrated more clearly in the utility model embodiment or technical scheme, to the accompanying drawing of required use in embodiment or technical scheme description be briefly described below, apparently, accompanying drawing in the following describes is only of the present utility model compared with exemplary embodiments or structure composition, for those of ordinary skill in the art, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.
Fig. 1 is the phase shortage of a kind of three-phase four-wire system of the utility model optical fiber detection and a kind of specific embodiment schematic diagram of power failure alarm device.
Fig. 2 is the specific embodiment schematic diagram of the phase shortage of a kind of three-phase four-wire system of the utility model optical fiber detection and the remote signaling processing of power failure alarm device.
Embodiment
For making object, technical scheme and the advantage of the utility model embodiment clearer, below in conjunction with the accompanying drawing in the utility model embodiment, technical scheme in the utility model embodiment is clearly and completely described, obviously, described embodiment is only a part of embodiment of the present utility model, instead of whole embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not making all other embodiment that obtain under creative work prerequisite, all belong to the scope of the utility model protection.
As accompanying drawing 1 and accompanying drawing 2 have provided phase shortage that a kind of three-phase four-wire system of the utility model optical fiber detects and a specific embodiment of power failure alarm device, and the specific embodiment schematic diagram of remote signaling processing.
Now with embodiment, the utility model is further illustrated by reference to the accompanying drawings.
As shown in Figure 1, be the phase shortage of a kind of three-phase four-wire system of the utility model optical fiber detection and a kind of specific embodiment schematic diagram of power failure alarm device.It is characterized in that:
Comprise A phase detecting circuit, B phase detecting circuit and C phase detecting circuit, every testing circuit is made up of similar device, the head end of every testing circuit is received respectively in the phase line of A, B and C three-phase supply, or receive respectively on the equivalent electrical circuit delivery outlet (such as the three-phase delivery outlet after voltage transformer (VT) conversion) that detects A, B and C three-phase supply phase line, the tail end of every testing circuit is connected together, form Y connection, its common node is connected on center line N;
A phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R a1, resistance R a2 is composed in series, its one end is connected on A phase power supply, electricity is by diode Da1 with light signal change-over circuit, diode Da2, diode Da3, diode Da4, capacitor C a1, resistance R a3, voltage stabilizing diode Dza1, resistance R a4 and optical fiber launching seat HFa composition, wherein, diode Da1, diode Da2, diode Da3 and diode Da4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C a1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R a3 and voltage stabilizing diode Dza1, further, between the negative electrode of voltage stabilizing diode Dza1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Ra4 and optical fiber launching seat HFa, wherein, one end of the anode connecting resistance Ra4 of optical fiber launching seat HFa, the negative electrode of optical fiber launching seat HFa connects the anode of voltage stabilizing diode Dza1,
B phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R b1, resistance R b2 is composed in series, its one end is connected on B phase power supply, electricity is by diode Db1 with light signal change-over circuit, diode Db2, diode Db3, diode Db4, capacitor C b1, resistance R b3, voltage stabilizing diode Dzb1, resistance R b4 and optical fiber launching seat HFb composition, wherein, diode Db1, diode Db2, diode Db3 and diode Db4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C b1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R b3 and voltage stabilizing diode Dzb1, further, between the negative electrode of voltage stabilizing diode Dzb1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Rb4 and optical fiber launching seat HFb, wherein, one end of the anode connecting resistance Rb4 of optical fiber launching seat HFb, the negative electrode of optical fiber launching seat HFb connects the anode of voltage stabilizing diode Dzb1,
C phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R c1, resistance R c2 is composed in series, its one end is connected on C phase power supply, electricity is by diode Dc1 with light signal change-over circuit, diode Dc2, diode Dc3, diode Dc4, capacitor C c1, resistance R c3, voltage stabilizing diode Dzc1, resistance R c4 and optical fiber launching seat HFc composition, wherein, diode Dc1, diode Dc2, diode Dc3 and diode Dc4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C c1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R c3 and voltage stabilizing diode Dzc1, further, between the negative electrode of voltage stabilizing diode Dzc1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Rc4 and optical fiber launching seat HFc, wherein, one end of the anode connecting resistance Rc4 of optical fiber launching seat HFc, the negative electrode of optical fiber launching seat HFc connects the anode of voltage stabilizing diode Dzc1,
Each phase detecting circuit in the middle of A phase detecting circuit, B phase detecting circuit and C phase detecting circuit is that the electric signal of place phase is converted to after light signal, carry out remote signal conveying by corresponding electricity and light conversion branch road again, central arbitrary phase detecting circuit is while can't detect photosignal, after logic judgement, think this phase power phase shortage, if all can't detect photosignal, after logic judgement, think that three-phase supply is power-off.
As shown in Figure 2, be the specific embodiment schematic diagram of the phase shortage of a kind of three-phase four-wire system of the utility model optical fiber detection and the remote signaling processing of power failure alarm device.Comprise opto-electronic conversion and shaping circuit 1, logic judging circuit 2, circuit 3 and auxiliary power circuit 4; The light signal that A phase shown in respective figure 1, B phase and C are come by the conversion of optical fiber launching seat, the signal of first every phase voltage converts electric signal through opto-electronic conversion and shaping circuit 1 to light signal, go forward side by side after the Shape correction of line correlation, be transported to again the signal output that logic judging circuit 2 judges whether to carry out phase shortage or power-off, do the post-processed of signal finally by circuit 3.Wherein, auxiliary power circuit 4 provides power supply for above-mentioned opto-electronic conversion and shaping circuit 1, logic judging circuit 2 and circuit 3.
The above, be only preferred embodiment of the present utility model, not the utility model done to any pro forma restriction.If the utility model embodiment is carried out to various distortion or amendment, but still within spirit of the present utility model and principle, within all should being included in claim protection domain of the present utility model.
Claims (2)
1. three-phase four-wire system detects with optical fiber phase shortage and a power failure alarm device, is characterized in that:
Comprise A phase detecting circuit, B phase detecting circuit and C phase detecting circuit, every testing circuit is made up of similar device, the head end of every testing circuit is received respectively in the phase line of A, B and C three-phase supply, the tail end of every testing circuit is connected together, form Y connection, its common node is connected on center line N;
Described A phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R a1, resistance R a2 is composed in series, its one end is connected on A phase power supply, electricity is by diode Da1 with light signal change-over circuit, diode Da2, diode Da3, diode Da4, capacitor C a1, resistance R a3, voltage stabilizing diode Dza1, resistance R a4 and optical fiber launching seat HFa composition, wherein, diode Da1, diode Da2, diode Da3 and diode Da4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C a1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R a3 and voltage stabilizing diode Dza1, further, between the negative electrode of voltage stabilizing diode Dza1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Ra4 and optical fiber launching seat HFa, wherein, one end of the anode connecting resistance Ra4 of optical fiber launching seat HFa, the negative electrode of optical fiber launching seat HFa connects the anode of voltage stabilizing diode Dza1,
Described B phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R b1, resistance R b2 is composed in series, its one end is connected on B phase power supply, electricity is by diode Db1 with light signal change-over circuit, diode Db2, diode Db3, diode Db4, capacitor C b1, resistance R b3, voltage stabilizing diode Dzb1, resistance R b4 and optical fiber launching seat HFb composition, wherein, diode Db1, diode Db2, diode Db3 and diode Db4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C b1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R b3 and voltage stabilizing diode Dzb1, further, between the negative electrode of voltage stabilizing diode Dzb1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Rb4 and optical fiber launching seat HFb, wherein, one end of the anode connecting resistance Rb4 of optical fiber launching seat HFb, the negative electrode of optical fiber launching seat HFb connects the anode of voltage stabilizing diode Dzb1,
Described C phase detecting circuit further comprises reduction voltage circuit and electricity and light signal change-over circuit, wherein, reduction voltage circuit is by resistance R c1, resistance R c2 is composed in series, its one end is connected on C phase power supply, electricity is by diode Dc1 with light signal change-over circuit, diode Dc2, diode Dc3, diode Dc4, capacitor C c1, resistance R c3, voltage stabilizing diode Dzc1, resistance R c4 and optical fiber launching seat HFc composition, wherein, diode Dc1, diode Dc2, diode Dc3 and diode Dc4 composition rectifier bridge, two ac input ends of this rectifier bridge meet respectively the other end of above-mentioned reduction voltage circuit and the center line N of three-phase four-wire system power supply, between the direct-flow positive pole end and negative pole end of this rectification bridge output end, correspondingly be parallel with the capacitor C c1 strobing, also be parallel with in addition the typical voltage stabilizing branch road being formed by resistance R c3 and voltage stabilizing diode Dzc1, further, between the negative electrode of voltage stabilizing diode Dzc1 and anode, be also parallel with the electricity and the light conversion branch road that are composed in series by current-limiting resistance Rc4 and optical fiber launching seat HFc, wherein, one end of the anode connecting resistance Rc4 of optical fiber launching seat HFc, the negative electrode of optical fiber launching seat HFc connects the anode of voltage stabilizing diode Dzc1,
Each phase detecting circuit in the middle of described A phase detecting circuit, B phase detecting circuit and C phase detecting circuit is that the electric signal of place phase is converted to after light signal, carry out remote signal conveying by corresponding electricity and light conversion branch road again, central arbitrary phase detecting circuit is while can't detect photosignal, after logic judgement, think this phase power phase shortage, if all can't detect photosignal, after logic judgement, think that three-phase supply is power-off.
2. a kind of three-phase four-wire system according to claim 1 detects with optical fiber phase shortage and power failure alarm device, it is characterized in that: every described testing circuit head end, also can receive respectively on the equivalent electrical circuit output port that detects A, B and C three-phase supply phase line, the tail end of every testing circuit is connected together, form Y connection, its common node is connected on center line N.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201420134935.4U CN203811695U (en) | 2014-03-25 | 2014-03-25 | Three-phase four-wire system fiber detection open-phase and power-off alarm device |
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| CN201420134935.4U CN203811695U (en) | 2014-03-25 | 2014-03-25 | Three-phase four-wire system fiber detection open-phase and power-off alarm device |
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| CN203811695U true CN203811695U (en) | 2014-09-03 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104698259A (en) * | 2015-02-06 | 2015-06-10 | 四川蓝讯宝迩电子科技有限公司 | Electrified detection circuit suitable for three-phase electrical system |
| CN112557772A (en) * | 2020-12-07 | 2021-03-26 | 天津津航计算技术研究所 | Small-size alternating current of single power keeps apart detection module |
| CN114336509A (en) * | 2020-09-27 | 2022-04-12 | 中车株洲电力机车研究所有限公司 | Solid-state direct current breaker control system and direct current system |
-
2014
- 2014-03-25 CN CN201420134935.4U patent/CN203811695U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104698259A (en) * | 2015-02-06 | 2015-06-10 | 四川蓝讯宝迩电子科技有限公司 | Electrified detection circuit suitable for three-phase electrical system |
| CN114336509A (en) * | 2020-09-27 | 2022-04-12 | 中车株洲电力机车研究所有限公司 | Solid-state direct current breaker control system and direct current system |
| CN112557772A (en) * | 2020-12-07 | 2021-03-26 | 天津津航计算技术研究所 | Small-size alternating current of single power keeps apart detection module |
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