CN108318730A - A kind of communication power supply voltage detecting circuit - Google Patents
A kind of communication power supply voltage detecting circuit Download PDFInfo
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- CN108318730A CN108318730A CN201810288484.2A CN201810288484A CN108318730A CN 108318730 A CN108318730 A CN 108318730A CN 201810288484 A CN201810288484 A CN 201810288484A CN 108318730 A CN108318730 A CN 108318730A
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- 230000005611 electricity Effects 0.000 claims description 5
- 238000001514 detection method Methods 0.000 abstract description 10
- 230000008901 benefit Effects 0.000 abstract description 4
- 238000005516 engineering process Methods 0.000 description 3
- 206010033799 Paralysis Diseases 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
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- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Abstract
The invention discloses a kind of communication power supply voltage detecting circuit, it is incomplete mainly to solve section communication power detecting existing in the prior art, protection, the problems such as increasing equipment input cost.The detection circuit includes the air switch QF being serially connected in respectively on telecommunication source line and contactor KM, parallel connection is articulated in voltage transformer T1 and T2 on telecommunication source line, the first filter circuit being connect with voltage transformer T1, the diode VD1 being connect with the first filter circuit, the comparator A1 being connect with diode VD1, the resistance R1 and resistance R2 being connect with comparator A1, the second filter circuit being connect with voltage transformer T2, the diode VD2 being connect with the second filter circuit, the comparator A2 being connect with diode VD2, the resistance R3 and resistance R4 being connect respectively with comparator A2, connect respectively with comparator A1 and comparator A2 with door chip, the trigger circuit being connect with door chip.Invention has many advantages, such as that simple in structure, detection is reliable, of low cost.
Description
Technical field
The present invention relates to field of communication technology, especially a kind of communication power supply voltage detecting circuit.
Background technology
Critical infrastructures of the communication power supply as entire communication network, the stabilization of communication power supply are reliably to ensure communication
The key of the safe and reliable operation of system, once power supply system for communications failure causes the power failure to communication equipment, communication equipment
It can not just run, telecommunication circuit interruption, communication system paralysis be will result in, to cause great economic and social benefit to damage
It loses.Therefore, in order to ensure communication equipment reliability service, important communication system is all made of dual power supply or increase uninterruptedly supplies
Electric system.Due to equipment input cost, currently, part secondary communication power supply still uses single supply to power, communication electricity
It is connected by air switch between source and communication system.When communication system short circuit, air switch can quickly disconnect faulty equipment,
But when overvoltage occurred for communication system, air switch but cannot quickly disconnect faulty equipment, cause other normal communications
Damage.In addition, important communication equipment uses the protection system of microprocessor, by the voltage and current for acquiring communication power supply
Amount, and AD converter converts thereof into the readable digital quantity of microprocessor, this protection system function is complete, reliable in action, but
To also increase equipment input cost, it is secondary with communication equipment below in be but not suitable for.
Accordingly, it is desirable to provide a kind of communication power supply voltage detecting circuit cheap, protection is complete, ensures communication power supply
Safe and reliable operation also can quick disengagement failure equipment in communication equipment fault.
Invention content
Place against the above deficiency, the purpose of the present invention is to provide a kind of communication power supply voltage detecting circuits, main to solve
Section communication power detecting certainly existing in the prior art, protection are incomplete, the problems such as increasing equipment input cost.
To achieve the goals above, the technical solution adopted by the present invention is as follows：
A kind of communication power supply voltage detecting circuit, including the air switch that is serially connected on three-phase four-wire system telecommunication source line
QF, the contactor KM being serially connected on three-phase four-wire system telecommunication source line, parallel connection is articulated on telecommunication source line and input terminal is distinguished
The voltage transformer T1 being connect with telecommunication source line L2 and L1, parallel connection be articulated on telecommunication source line and input terminal respectively with communication
The voltage transformer T2 that power cord L2 is connected with L3, the first filter circuit being connect with mono- output ends of voltage transformer T1, input
Hold the diode VD1 being connect with the first filter circuit, the comparator A1 that input cathode is connect with diode VD1 output ends, one end
The resistance R1 and resistance R2 being connect respectively with comparator A1 input anodes, the second filter being connect with mono- output ends of voltage transformer T2
Wave circuit, the diode VD2 that input terminal is connect with the second filter circuit input the ratio of cathode and the connection of diode VD2 output ends
Compared with device A2, the resistance R3 and resistance R4 that one end is connect with comparator A2 input anode respectively, input terminal respectively with comparator A1 and
Comparator A2 connections with door chip, the trigger circuit being connect with door chip output, wherein the resistance R2 and resistance R4
The other end ground connection.
Specifically, first filter circuit include capacitance C1 that one end is connect with voltage transformer T1 and one end with
The other end of the resonance circuit L1C2, the resonance circuit L1C2 of the capacitance C1 other ends are grounded.
Further, second filter circuit includes the capacitance C3 and one end that one end is connect with voltage transformer T2
It is grounded with the other end of the resonance circuit L2C4, the resonance circuit L2C4 of the capacitance C3 other ends.
Preferably, another output end of the voltage transformer T1 and voltage transformer T2 is grounded respectively；The voltage is mutual
The no-load voltage ratio of sensor T1 and voltage transformer T2 are 380/5.
Further, described to be connect with the output end of comparator A1 with the input terminal 1A of door chip, the input with door chip
End 1B is connect with the output end of comparator A2, is connect with trigger circuit with the output end 1Y of door chip.
Further, the trigger circuit is the triode VT that base stage is connect with the output end 1Y of door chip, three pole
The collector of pipe VT is connect with contactor KM and emitter is grounded.
Preferably, described and door chip is 74LS08.
Further, the resonance circuit L1C2 includes the inductance L1 being mutually in parallel and capacitance C2, the inductance L1 are
3.6H, capacitance C2 are 2.8uF.
Further, the resonance circuit L2C4 includes the inductance L2 being mutually in parallel and capacitance C4, the inductance L2 are
3.6H, capacitance C4 are 2.8uF.
Further, the resistance R1 is 5.3k Ω, and resistance R2 is 4.7k Ω, and R3 is 5.3k Ω, and resistance R4 is 4.7k Ω,
Capacitance C1 is 5.5uF, C2 5.5uF.
Compared with prior art, the invention has the advantages that：
(1) present invention detects communication power supply inlet wire using the voltage transformer of incomplete star-connection, can effectively examine
The voltage change trend for surveying three-phase four-wire system, when arbitrarily mutually short circuit grounding failure occurs for communication power supply, the voltage of normal phase will
Increase therewith, by detecting the variation of voltage, and with and with constant differential pressure voltage-contrast, passes through the voltage judgement for judging acquisition
Telecommunication circuit is blocked in voltage fluctuation situation in telecommunication circuit, triggered circuit connection.To play cutting for failure communication equipment
It removes, ensures the safe and reliable operation of other communication equipments, also avoid the long charged operation of failure communication equipment, prevent from communicating
The further expansion of power failure.In addition, voltage judgement is carried out by the way that comparator is arranged, compared with traditional microprocessor,
Equipment cost is more cheap, can be widely used in secondary communication power detecting, keeps communication power supply operation more reliable.
(2) present invention in voltage transformer output end by accessing filter circuit, on the one hand, it is logical can to exclude communication power supply
Interference of the generated surge voltage to detection circuit when electricity or power-off, ensures to detect accurate voltage signal.On the other hand, it filters
Wave circuit can effectively shield the interference that signal of communication is transmitted by communication power supply, the signal of communication string for avoiding telecommunication source line from loading
Enter in detection circuit, thus, which the anti-interference ability of detection circuit can be improved.Moreover, in the output string of filter circuit
It is connected to diode, the voltage AC signal lower half waveform of acquisition is shielded, while ensureing to detect valid data, is decreased
The comparison workload of comparator.
(3) collection point voltage signal is passed through ratio by the present invention using the star-like voltage mutual inductor interstar connection of imperfection
After being compared compared with device, does and operation, more traditional microprocessor carry out digital-to-analogue conversion, then the speed handled through microprocessor
Degree is obviously improved, and is shortened the time of cut-out communication failure, is ensured the normal operation of other communication equipments.
Description of the drawings
Fig. 1 is the principle of the present invention wiring diagram.
Specific implementation mode
The invention will be further described with reference to the accompanying drawings and examples, and embodiments of the present invention include but not limited to
The following example.
Embodiment
As shown in Figure 1, the present invention provides a kind of communication power supply voltage detecting circuit, the communication of communication equipment both can guarantee
Carrier signal normal transmission can also detect communication equipment operation conditions in real time, when failure, also can quickly, accurately cut off failure
Communication equipment prevents communication failure from further expanding, and ensures communication system security, stable operation.Concrete scheme is as follows：
The detection circuit includes the air switch QF being serially connected on three-phase four-wire system telecommunication source line, is serially connected in three-phase and four-line
Contactor KM on telecommunication source line processed, parallel connection be articulated on telecommunication source line and input terminal respectively with telecommunication source line L2 and L1
The voltage transformer T1 of connection, parallel connection is articulated on telecommunication source line and input terminal is connect with telecommunication source line L2 and L3 respectively
Voltage transformer T2, the first filter circuit being connect with mono- output ends of voltage transformer T1, input terminal and the first filter circuit connect
The diode VD1 connect, the comparator A1 that input cathode is connect with diode VD1 output ends, one end is inputted with comparator A1 respectively
The resistance R1 and resistance R2 of anode connection, the second filter circuit being connect with mono- output ends of voltage transformer T2, input terminal and the
The diode VD2 of two filter circuits connection, the input comparator A2 that is connect with diode VD2 output ends of cathode, one end respectively with
The resistance R3 and resistance R4 of comparator A2 input anode connections, what input terminal was connect with comparator A1 and comparator A2 respectively
74LS08 and door chip, the trigger circuit being connect with door chip output, wherein another termination of resistance R2 and resistance R4
Another output end of ground, voltage transformer T1 and voltage transformer T2 are grounded respectively.
First filter circuit of the detection circuit include the capacitance C1 that one end is connect with voltage transformer T1 and one end with
The resonance circuit L1C2 of the capacitance C1 other ends；The other end of the resonance circuit L1C2 is grounded.Second filter circuit includes one end
The capacitance C3 being connect with the voltage transformer T2 and resonance circuit L2C4 of one end and the capacitance C3 other ends；The resonance circuit
The other end of L2C4 is grounded.
The detection circuit is connect with the input terminal 1A of door chip with the output end of comparator A1, the input terminal with door chip
1B is connect with the output end of comparator A2, is connect with trigger circuit with the output end 1Y of door chip.Trigger circuit is base stage and door
The collector of the triode VT, the triode VT of the output end 1Y connections of chip are connect with contactor KM and emitter connects
Ground.
Wherein, the no-load voltage ratio of the voltage transformer T1 and voltage transformer T2 of the present embodiment are 380/5, and inductance L1 is
3.6H, capacitance C2 are 2.8uF, and inductance L2 is 3.6H, and capacitance C4 is 2.8uF, and resistance R1 is 5.3k Ω, and resistance R2 is 4.7k Ω,
R3 is 5.3k Ω, and resistance R4 is 4.7k Ω, and capacitance C1 is 5.5uF, and C2 5.5uF, power supply VCC are 12V.When communication power supply is powered
When, the first filter circuit and the second filter circuit play effective shielding to surge voltage, ensure voltage detecting circuit from damage
It is bad.At this point, comparator A1 and to compare the input cathode voltage of A2 be 5.64V, the voltage for inputting cathode is 5V, comparator A1 and
Comparator A2 exports high level, at 74LS08 and the effect of door chip, exports high level, driving triode VT collectors and hair
Emitter-base bandgap grading is connected, and contactor KM obtains electric so that the main contact of contactor KM is attracted, communication power supply normal power supply.When in communication power supply
When arbitrary mutually generation earth fault or overvoltage, comparator A1 and/or comparator A2 input cathode voltages are more than input anode
Voltage, comparator A1 and/or comparator A2 export low level, defeated on output end 1Y under the action of 4LS08 and door chip
Go out low level, at this point, being truncated between the emitter and collector of triode VT so that contactor KM dead electricity, contactor KM master
Contact disconnects communication power supply connection, cuts off the communication equipment of failure, plays the protective effect of communication equipment.
Filter circuit is cleverly arranged in the present invention, effectively completely cuts off the carrier signal on telecommunication source line, prevents carrier wave from believing
Number seal in measure loop.In addition, ensureing the effective premise of detection data, setting diode is by effectively detecting voltage wave
Shape reduces the comparison workload of comparator.Moreover, pass through the voltage transformer of incomplete star-connection, acquisition communication electricity
The voltage change situation in source, and the on or off by controlling triode, control the break-make of communication power supply, compared with microprocessor
Protection is compared, and action is faster.In conclusion invention has many advantages, such as that simple in structure, detection is reliable, of low cost, protection is reliable,
Foreground and promotional value are had a vast market in field of communication technology.
Above-described embodiment is merely a preferred embodiment of the present invention, and it is not intended to limit the protection scope of the present invention, as long as using
The design principle of the present invention, and the non-creative variation worked and made is carried out on this basis, it should all belong to the present invention's
Within protection domain.
Claims (10)
1. a kind of communication power supply voltage detecting circuit, including the air switch QF that is serially connected on three-phase four-wire system telecommunication source line,
It is characterized in that, further including the contactor KM being serially connected on three-phase four-wire system telecommunication source line, parallel connection is articulated in telecommunication source line
The voltage transformer T1 that upper and input terminal is connect with telecommunication source line L2 and L1 respectively, parallel connection is articulated on telecommunication source line and defeated
Enter the voltage transformer T2 that end is connect with telecommunication source line L2 and L3 respectively, first connect with mono- output ends of voltage transformer T1
Filter circuit, the diode VD1 that input terminal is connect with the first filter circuit, input cathode are connect with diode VD1 output ends
Comparator A1, the resistance R1 and resistance R2 that one end is connect with comparator A1 input anodes respectively, exports with voltage transformer T2 mono-
Hold the second filter circuit of connection, the diode VD2 that input terminal is connect with the second filter circuit, input cathode and diode VD2
The comparator A2 of output end connection, the resistance R3 and resistance R4 that one end is connect with comparator A2 input anodes respectively, input terminal point
Do not connect with comparator A1 and comparator A2 with door chip, the trigger circuit being connect with door chip output；The resistance
The other end of R2 and resistance R4 are grounded；Another output end of the voltage transformer T1 and voltage transformer T2 is grounded respectively.
2. a kind of communication power supply voltage detecting circuit according to claim 1, which is characterized in that first filter circuit
The capacitance C1 being connect with voltage transformer T1 including one end and resonance circuit L1C2 of one end and the capacitance C1 other ends；It is described
The other end of resonance circuit L1C2 is grounded.
3. a kind of communication power supply voltage detecting circuit according to claim 1, which is characterized in that second filter circuit
The capacitance C3 being connect with voltage transformer T2 including one end and resonance circuit L2C4 of one end and the capacitance C3 other ends；It is described
The other end of resonance circuit L2C4 is grounded.
4. according to a kind of communication power supply voltage detecting circuit of claims 1 to 3 any one of them, which is characterized in that the electricity
It is 380/5 to press the no-load voltage ratio of mutual inductor T1 and voltage transformer T2.
5. according to a kind of communication power supply voltage detecting circuit of claims 1 to 3 any one of them, which is characterized in that it is described with
The input terminal 1A of door chip is connect with the output end of comparator A1, is connected with the output end of the input terminal 1B and comparator A2 of door chip
It connects, is connect with trigger circuit with the output end 1Y of door chip.
6. a kind of communication power supply voltage detecting circuit according to claim 5, which is characterized in that the trigger circuit is base
The triode VT that pole is connect with the output end 1Y of door chip, the collector of the triode VT connect and emit with contactor KM
Pole is grounded.
7. according to a kind of communication power supply voltage detecting circuit of claims 1 to 3 any one of them, which is characterized in that it is described with
Door chip is 74LS08.
8. a kind of communication power supply voltage detecting circuit according to claim 2, which is characterized in that the resonance circuit L1C2
It is 3.6H including the inductance L1 being mutually in parallel and capacitance C2, the inductance L1, capacitance C2 is 2.8uF.
9. a kind of communication power supply voltage detecting circuit according to claim 3, which is characterized in that the resonance circuit L2C4
It is 3.6H including the inductance L2 being mutually in parallel and capacitance C4, the inductance L2, capacitance C4 is 2.8uF.
10. a kind of communication power supply voltage detecting circuit according to claim 1, which is characterized in that the resistance R1 is
5.3k Ω, resistance R2 are 4.7k Ω, and R3 is 5.3k Ω, and resistance R4 is 4.7k Ω, and capacitance C1 is 5.5uF, C2 5.5uF.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810288484.2A CN108318730A (en) | 2018-03-30 | 2018-03-30 | A kind of communication power supply voltage detecting circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810288484.2A CN108318730A (en) | 2018-03-30 | 2018-03-30 | A kind of communication power supply voltage detecting circuit |
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| CN108318730A true CN108318730A (en) | 2018-07-24 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201810288484.2A Pending CN108318730A (en) | 2018-03-30 | 2018-03-30 | A kind of communication power supply voltage detecting circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111751759A (en) * | 2020-06-28 | 2020-10-09 | 国网北京市电力公司 | Three-phase charging gun output short circuit detection circuit and detection method |
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| CN106546804A (en) * | 2016-12-27 | 2017-03-29 | 池州学院 | A kind of transistor over-current detection circuit |
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| CN107294058A (en) * | 2017-06-27 | 2017-10-24 | 合肥尚硕新能源有限公司 | A kind of overvoltage undervoltage detection circuit applied to solar energy power accumulating power supply |
| CN208283451U (en) * | 2018-03-30 | 2018-12-25 | 成都众宜天成科技有限公司 | A kind of communication power supply voltage detecting circuit |
-
2018
- 2018-03-30 CN CN201810288484.2A patent/CN108318730A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6395364A (en) * | 1986-10-13 | 1988-04-26 | Fujitsu Denso Ltd | Overvoltage/low voltage detection circuit |
| CN2742669Y (en) * | 2004-08-30 | 2005-11-23 | 株洲九方电器设备有限公司 | Novel control power |
| CN201349072Y (en) * | 2008-12-22 | 2009-11-18 | 南京邮电大学 | High-accuracy over-current protecting socket |
| CN102170133A (en) * | 2011-04-26 | 2011-08-31 | 湖北中兴电力试验研究有限公司 | Double-tuned filter suitable for automatic tracking and compensation arc extinguishing coil complete equipment |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111751759A (en) * | 2020-06-28 | 2020-10-09 | 国网北京市电力公司 | Three-phase charging gun output short circuit detection circuit and detection method |
| CN111751759B (en) * | 2020-06-28 | 2022-11-01 | 国网北京市电力公司 | Three-phase charging gun output short circuit detection circuit and detection method |
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