CN203720266U - System for monitoring surface contamination conductivity of insulator - Google Patents
System for monitoring surface contamination conductivity of insulator Download PDFInfo
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- CN203720266U CN203720266U CN201320830819.1U CN201320830819U CN203720266U CN 203720266 U CN203720266 U CN 203720266U CN 201320830819 U CN201320830819 U CN 201320830819U CN 203720266 U CN203720266 U CN 203720266U
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- 239000012212 insulator Substances 0.000 title claims abstract description 62
- 238000012544 monitoring process Methods 0.000 title claims abstract description 25
- 238000011109 contamination Methods 0.000 title abstract description 4
- 238000012545 processing Methods 0.000 claims abstract description 19
- 238000012360 testing method Methods 0.000 claims description 8
- 230000003534 oscillatory effect Effects 0.000 claims description 7
- 230000015572 biosynthetic process Effects 0.000 claims 2
- 238000000034 method Methods 0.000 abstract description 11
- 238000005259 measurement Methods 0.000 abstract description 6
- 238000004891 communication Methods 0.000 abstract description 4
- 230000008569 process Effects 0.000 abstract description 4
- 238000013480 data collection Methods 0.000 abstract 2
- 239000003990 capacitor Substances 0.000 description 16
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 6
- 229910052710 silicon Inorganic materials 0.000 description 6
- 239000010703 silicon Substances 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000008859 change Effects 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000010295 mobile communication Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
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- 239000003595 mist Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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Abstract
The utility model discloses a system for monitoring the surface contamination conductivity of an insulator. The system comprises a measurement unit, a data collection unit, a data processing unit and a computer which are successively connected. The measurement unit, the data collection unit and the data processing unit are connected by wires, and the data processing unit is connected to the computer via a wireless communication network. A signal source voltage signal and a fixed value resistor voltage signal are obtained from the measurement unit and are processed by the data processing unit separately to obtain an angular phase difference of the two signals, and the conductivity is calculated from the angular phase difference. The system is a novel system for monitoring the surface contamination conductivity of an insulator. The measurement process is simple, and the result is accurate and reliable.
Description
Technical field
The utility model relates to on-line monitoring field, is specifically related to a kind of system of monitoring pollution severity of insulators conductivity.
Background technology
For a long time, the construction of China's electric power networks goes from strength to strength.Electric transmission line isolator in various environment, is subject to aerial strong-electromagnetic field, suddenly cold and hot for a long time, floating filthy particle, liquid in air, solids etc., add rain, mist, reveals ice-melt, the mal-conditions such as snow melt, the electrical strength of insulator surface reduces greatly, if do not carry out for a long time filth, does not process, and pollution flashover accident just easily occurs, the loss of pollution flashover accident is ten times of damage to crops caused by thunder accident, endangers huge.
Monitoring pollution severity of insulators conductivity is significant to anti-pollution flashover.Monitoring pollution severity of insulators conductivity can be understood the dirty and situation of making moist of insulator surface contamination in real time, for formulating pollution severity of insulators cleaning works, provides guidance.
Current existing pollution severity of insulators monitoring system has image processing techniques, by the characteristic quantity extracting in pollution severity of insulators photo, analyzes judgement; Monitor the low-frequency acoustic signal sending when pollution severity of insulators flashover discharges, according to the low-frequency acoustic signal obtaining, judge the size of pollution severity of insulators amount; The microwave signal of sending during the electric discharge of monitoring pollution severity of insulators and monitoring pollution severity of insulators electric discharge ultrasonic signal etc.The general error of system of this class monitoring pollution severity of insulators is larger, obtains correction factor difficult, and precision prescribed height is apparatus expensive.The system of another kind of monitoring pollution severity of insulators has monitoring Leakage Current method and monitoring voltage distribution, and this monitoring system is subject to hyperbaric environment serious interference, complex disposal process, and analysis need to possess certain experience and professional knowledge.
Utility model content
The shortcoming and deficiency that in order to overcome prior art, exist, the utility model provides a kind of system of monitoring pollution severity of insulators conductivity.
The utility model adopts following technical scheme:
Monitor a system for pollution severity of insulators conductivity, comprise the measuring unit, data acquisition unit, data processing unit and the computing machine that connect successively;
Described measuring unit is by signal source circuit, fixed value resistance R
s, definite value capacitor C
sequivalent resistance R with pollution severity of insulators
xform, wherein definite value capacitor C
sequivalent resistance R with pollution severity of insulators
xafter parallel connection successively with described fixed value resistance R
s, signal source circuit series connection;
Described data processing unit consists of the first zero-crossing comparator, the second zero-crossing comparator and phase angle difference testing circuit.
Described signal source circuit consists of the power circuit connecting successively, oscillatory circuit, low-pass filter circuit and range-adjusting circuit.
Described fixed value resistance R
sby more than one resistance serial or parallel connection or series-parallel connection, formed; Described definite value capacitor C
sby more than one capacitances in series or parallel connection or series-parallel connection, formed; Pollution severity of insulators equivalent resistance R
xrefer to be suspended on uncharged on electric power line pole tower or for the equivalent resistance of measuring pollution severity of insulators or hang the equivalent resistance of uncharged pollution severity of insulators in the growth cabinet of laboratory.
Described the first zero-crossing comparator is identical with the second zero-crossing comparator structure, includes the 3rd operational amplifier F
3, triode M
1, the 7th resistance R
7, the 8th resistance R
8and the 9th resistance R
9, described the 7th resistance R
7be connected to the 3rd operational amplifier F
3negative input and signal source circuit between, the 8th resistance R
8be connected to triode M
1base stage and the 3rd operational amplifier F
3output terminal between, the 9th resistance R
9be connected to described triode M
1collector and direct voltage source between, the 3rd operational amplifier F
3electrode input end ground wire, triode M
1emitter grounding line.
Described phase angle difference testing circuit is by the first JK flip-flop JK
1, the second JK flip-flop JK
2and Sheffer stroke gate G forms; Described the first JK flip-flop JK
1and the second JK flip-flop JK
2structure and parameters be identical, wherein first of the first JK flip-flop output Q
1with the second output
meet respectively the 3rd input J of the second JK flip-flop
2with the 4th input K
2, the 3rd output Q of the second JK flip-flop
2with the 4th output
meet respectively the first input K of the first JK flip-flop
1with the second input J
1, the input end of Sheffer stroke gate G meets respectively the first output terminal Q of the first JK flip-flop
1the 3rd output terminal Q with described the second JK flip-flop
2.
A method of monitoring pollution severity of insulators conductivity, comprises the steps:
The voltage signal of S1 data acquisition unit collection signal source circuit and the voltage signal of fixed value resistance, and by the signal collected data processing unit that is transferred to;
S2 data processing unit obtains the phase angle difference signal of two signals through processing, and this signal is arrived to computing machine by wireless network transmissions;
Whether the dutycycle d of the phase angle difference signal that S3 computing machine judgement receives through wireless network is less than 0.25, and be to calculate phase angle difference θ, otherwise again read phase angle difference signal dutyfactor, the poor dutycycle of read signal again,
The formula of described calculating phase angle difference θ is:
θ=d×360°
Wherein, θ is pollution severity of insulators phase angle difference, and d is phase angle difference dutycycle;
S4, according to phase angle difference θ, obtains pollution severity of insulators equivalent resistance R
xcomputing formula be:
Wherein, R
xfor the equivalent resistance of pollution severity of insulators, ω is the angular frequency in metering circuit, C
sfor definite value electric capacity, R
sfor fixed value resistance, θ is phase angle difference;
The computing formula that S5 further obtains pollution severity of insulators conductivity gamma is:
γ=fK
t/R
x
Wherein, f is insulator surface shape coefficient, K
tfor insulator surface temperature compensation coefficient, R
xequivalent resistance for pollution severity of insulators;
The conductivity that S6 computing machine obtains S5 compares with there is flashover alarming threshold value, whether judges transmission line of electricity in critical days, if in critical days, sends in time warning.
The beneficial effects of the utility model:
(1) the utility model measurement mechanism is simple, easy to connect, can directly observe the dynamic in real time of pollution severity of insulators conductivity, without complicated operation, the advantages such as good stability on computing machine;
(2) in monitoring pollution severity of insulators conductivity system of the present utility model, utilized the method for a kind of measurement two voltage signal phase angle differences to monitor pollution severity of insulators conductivity, this is the innovation in a kind of monitoring method.
Accompanying drawing explanation
Fig. 1 is a kind of structural drawing of monitoring the system of pollution severity of insulators conductivity of the utility model;
Fig. 2 is the utility model signal source circuit structural drawing;
Fig. 3 is the circuit connection diagram of the utility model measuring unit circuit;
Fig. 4 is the circuit connection diagram of the utility model zero-crossing comparator;
Fig. 5 is the circuit connection diagram of the utility model phase angle difference testing circuit;
Fig. 6 is a kind of process flow diagram of monitoring the method for pollution severity of insulators conductivity of the utility model.
Embodiment
Below in conjunction with embodiment and accompanying drawing, the utility model is described in further detail, but embodiment of the present utility model is not limited to this.
Embodiment
As shown in Figure 1, a kind of system of monitoring pollution severity of insulators conductivity, comprise the measuring unit, data acquisition unit, data processing unit and the computing machine that connect successively, above-mentioned measuring unit, data acquisition unit and data processing unit adopt wire to connect, and data processing unit is connected by wireless communication networks with computing machine;
As shown in Figure 3, described measuring unit is by signal source circuit Us, fixed value resistance R
s, definite value capacitor C
sequivalent resistance R with pollution severity of insulators
xform, wherein definite value capacitor C
sequivalent resistance R with pollution severity of insulators
xafter parallel connection successively with described fixed value resistance R
s, signal source circuit series connection;
Described fixed value resistance R
sby an above resistance serial or parallel connection or series-parallel connection, formed; Described definite value capacitor C
sby more than one capacitances in series or parallel connection or series-parallel connection, formed; Pollution severity of insulators equivalent resistance R
xrefer to be suspended on uncharged on electric power line pole tower or for the equivalent resistance of measuring pollution severity of insulators or hang the equivalent resistance of uncharged pollution severity of insulators in the growth cabinet of laboratory, preferably, in the present embodiment example, choose fixed value resistance R
sresistance be 1k Ω, definite value capacitor C
scapacitance be 50nF.
Described data acquisition unit has been to gather signal source circuit voltage signal and fixed value resistance Rs voltage signal in measuring unit, and the signal data collecting is transferred in data processor.
As shown in Figure 2, described signal source circuit consists of the power circuit connecting successively, oscillatory circuit 21, low-pass filter circuit 22 and range-adjusting circuit 23, wherein oscillatory circuit output sinusoidal ac signal frequency is 200～600Hz, the sinusoidal ac signal of exporting due to oscillatory circuit has high-frequency signal to disturb, therefore add low-pass filter, sinusoidal ac signal by low-pass filter after amplitude can decline, therefore also need to increase a range-adjusting circuit, finally by the sinusoidal ac signal access metering circuit meeting the demands.
Described power circuit adopts D.C. regulated power supply adapter, and direct current is provided, and the present embodiment preferably adopts two D.C. regulated power supply adapters as power supply, is the direct current supply voltage of provide ± 12V of circuit.
Described oscillatory circuit 21 is by the first operational amplifier F
1, the first resistance R
1, the second resistance R
2, the 3rd resistance R
3, the 4th resistance R
4, the first capacitor C
1, the second capacitor C
2, the first silicon diode D
1with the second silicon diode D
2form; Wherein, the first resistance R
1with the second resistance R
2resistance equate, the first capacitor C
1with the second capacitor C
2capacitance equate, the 4th resistance R
4resistance be the 3rd resistance R
32～3 times of resistance, the first silicon diode D
1with the second silicon diode D
2parameter identical; Then, the first resistance R
1with the first capacitor C
1after being in parallel, be connected to the first operational amplifier F
1electrode input end and ground wire between, the second resistance R
2with the second capacitor C
2after being in series, be connected to the first operational amplifier F
1electrode input end and the first operational amplifier F
1output terminal between, the 3rd resistance R
3be connected to the first operational amplifier F
1negative input and ground wire between, the first silicon diode D
1with the second silicon diode D
2after reverse parallel connection and the 4th resistance R
4series connection is connected to the first operational amplifier F
1negative input and the first operational amplifier F
1output terminal between.Preferably getting in the present embodiment the first operational amplifier model is UA741CN chip, and the frequency of oscillatory circuit output is 400Hz.
Described low-pass filter circuit 22 is to consist of the 5th resistance R 5 and the 3rd capacitor C 3, wherein, the 5th resistance R 5 is connected between the output terminal of operational amplifier F1 and the input end of range-adjusting circuit 23, and capacitor C 3 is connected between the input end and ground wire of range-adjusting circuit 23.Preferably, the resistance of choosing the 5th resistance R 5 in the present embodiment is 4.7k Ω, and the capacitance of the 3rd capacitor C 3 is 0.1 μ F.
Range-adjusting circuit 23 is by the second operational amplifier F
2, the 6th resistance and potentiometer R
w; Wherein, the maximum value of potentiometer Rw is 2～3 times of the 6th resistance R 6 resistances.The 6th resistance R 6 is connected between the negative input of the second operational amplifier F2 and the output terminal of low-pass filter circuit 22, potentiometer Rw is connected between the negative input of the second operational amplifier F2 and the output terminal of the second operational amplifier F2, the electrode input end ground wire of the second operational amplifier F2.Preferably, the model of choosing in the present embodiment the second operational amplifier F2 is UA741CN chip.
Described data processing unit consists of the first zero-crossing comparator, the second zero-crossing comparator and phase angle difference testing circuit.
As shown in Figure 4, described the first zero-crossing comparator and the second zero-crossing comparator are identical, include the 3rd operational amplifier F
3, triode M
1, the 7th resistance R
7, the 8th resistance R
8, the 9th resistance R
9, the 7th resistance R
7be connected to the 3rd operational amplifier F
3negative input and the signal source circuit of measuring unit between, the 8th resistance R
8be connected to triode M
1base stage and the 3rd operational amplifier F
3output terminal between, the 9th resistance R
9be connected to described triode M
1collector and direct voltage source between, the 3rd operational amplifier F
3electrode input end ground wire, the emitter grounding line of triode M1.Preferably, in the present embodiment, choose the 3rd operational amplifier F
3for OP07CP chip and choose triode M
1for 2222A element.
As shown in Figure 5, described phase angle difference testing circuit is by the first JK flip-flop JK
1, the second JK flip-flop JK
2and Sheffer stroke gate G forms; Described the first JK flip-flop JK
1and the second JK flip-flop JK
2structure and parameters be identical, wherein first of the first JK flip-flop output Q
1with the second output
meet respectively the 3rd input J of the second JK flip-flop
2with the 4th input K
2, the 3rd output Q of the second JK flip-flop
2with the 4th output
meet respectively the first input K of the first JK flip-flop
1with the second input J
1, the input end of Sheffer stroke gate meets respectively the first output terminal Q of the first JK flip-flop
1the 3rd output terminal Q with described the second JK flip-flop
2.Preferably, in the present embodiment, choosing JK flip-flop is SN74LS76A chip, and Sheffer stroke gate G chooses the Sheffer stroke gate 74LS00 chip with four inputs.
The effect of the first zero-crossing comparator and the second zero-crossing comparator is that sine wave signal is transformed into square-wave signal, when zero passage, change, phase angle difference testing circuit detects two signal phase angle differences, and then the phase angle difference signal detecting is sent to computing machine by wireless communication networks.
Described wireless communication networks is global system for mobile communications (GSM, Global System for Mobile Communications) or GPRS (GPRS, General packet Radio Services).
As shown in Figure 6, a kind of method of monitoring pollution severity of insulators conductivity, comprises the steps:
The voltage signal of S1 data acquisition unit collection signal source circuit and the voltage signal of fixed value resistance, and by the signal collected data processing unit that is transferred to;
S2 data processing unit obtains the phase angle difference signal of two signals through processing, and this signal is arrived to computing machine by wireless network transmissions, and described phase angle difference signal is to take absolute value and obtain phase angle difference after the initial phase angle of two voltage signals subtracts each other;
Whether the dutycycle d of the phase angle difference signal that the judgement of S3 computing machine receives through wireless network is less than 0.25, if not again reading phase angle difference signal dutyfactor, is to calculate phase angle difference θ:
θ=d * 360 °, wherein θ is pollution severity of insulators phase angle difference, d is phase angle difference dutycycle;
S4, according to phase angle difference θ, obtains pollution severity of insulators equivalent resistance R
xcomputing formula be:
Wherein, R
xfor the equivalent resistance of pollution severity of insulators, ω is the angular frequency in metering circuit, C
sfor definite value electric capacity, capacitance is 50nF, R
sfor fixed value resistance, resistance value is 1k Ω, and θ is pollution severity of insulators phase angle difference.
The computing formula that S5 further obtains pollution severity of insulators conductivity gamma is:
γ=fK
t/R
x
Wherein, f is insulator surface shape coefficient, K
tfor insulator surface temperature compensation coefficient, R
xequivalent resistance for pollution severity of insulators;
The computing formula of insulator surface shape coefficient f is:
Wherein, L is electrode leakage current width, and π D (x) is electrode length;
Insulator surface temperature compensation coefficient K
tcomputing formula be:
K
t=1.6/(1+0.03t)
Wherein, t is insulator surface temperature.
The conductivity that S6 computing machine obtains S5 compares with there is flashover alarming threshold value, whether judges transmission line of electricity in critical days, if in critical days, sends in time warning.
Above-described embodiment is preferably embodiment of the utility model; but embodiment of the present utility model is not limited by the examples; other any do not deviate from change, the modification done under Spirit Essence of the present utility model and principle, substitutes, combination, simplify; all should be equivalent substitute mode, within being included in protection domain of the present utility model.
Claims (3)
1. a system of monitoring pollution severity of insulators conductivity, is characterized in that, comprises the measuring unit, data acquisition unit, data processing unit and the computing machine that connect successively;
Described measuring unit is by signal source circuit, fixed value resistance (R
s), definite value electric capacity (C
s) and the equivalent resistance (R of pollution severity of insulators
x) formation, wherein definite value electric capacity (C
s) with the equivalent resistance (R of pollution severity of insulators
x) after parallel connection successively with described fixed value resistance (R
s), signal source circuit series connection;
Described data processing unit consists of the first zero-crossing comparator, the second zero-crossing comparator and phase angle difference testing circuit;
Described signal source circuit consists of the power circuit connecting successively, oscillatory circuit, low-pass filter circuit and range-adjusting circuit;
Described fixed value resistance (R
s) by more than one resistance serial or parallel connection or series-parallel connection, formed; Described definite value electric capacity (C
s) by more than one capacitances in series or parallel connection or series-parallel connection, formed; Pollution severity of insulators equivalent resistance (R
x) refer to be suspended on uncharged on electric power line pole tower or for the equivalent resistance of measuring pollution severity of insulators or hang the equivalent resistance of uncharged pollution severity of insulators in the growth cabinet of laboratory.
2. system according to claim 1, is characterized in that, described the first zero-crossing comparator is identical with the second zero-crossing comparator structure, includes the 3rd operational amplifier (F
3), triode (M
1), the 7th resistance (R
7), the 8th resistance (R
8) and the 9th resistance (R
9), described the 7th resistance (R
7) be connected to the 3rd operational amplifier (F
3) negative input and signal source circuit between, the 8th resistance (R
8) be connected to triode (M
1) base stage and the 3rd operational amplifier (F
3) output terminal between, the 9th resistance (R
9) be connected to described triode (M
1) collector and direct voltage source between, the 3rd operational amplifier (F
3) electrode input end ground wire, triode (M
1) emitter grounding line.
3. system according to claim 1, is characterized in that, described phase angle difference testing circuit is by the first JK flip-flop (JK
1), the second JK flip-flop (JK
2) and Sheffer stroke gate (G) formation; Described the first JK flip-flop (JK
1) and the second JK flip-flop (JK
2) structure and parameters be identical, wherein first of the first JK flip-flop output (Q
1) and the second output
meet respectively the 3rd input (J of the second JK flip-flop
2) and the 4th input (K
2), the 3rd output (Q of the second JK flip-flop
2) and the 4th output
meet respectively the first input (K of the first JK flip-flop
1) and the second input (J
1), the input end of Sheffer stroke gate (G) meets respectively the first output terminal (Q of the first JK flip-flop
1) and the 3rd output terminal (Q of described the second JK flip-flop
2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320830819.1U CN203720266U (en) | 2013-12-13 | 2013-12-13 | System for monitoring surface contamination conductivity of insulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320830819.1U CN203720266U (en) | 2013-12-13 | 2013-12-13 | System for monitoring surface contamination conductivity of insulator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203720266U true CN203720266U (en) | 2014-07-16 |
Family
ID=51159407
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320830819.1U Expired - Lifetime CN203720266U (en) | 2013-12-13 | 2013-12-13 | System for monitoring surface contamination conductivity of insulator |
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| Country | Link |
|---|---|
| CN (1) | CN203720266U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105973941A (en) * | 2016-04-29 | 2016-09-28 | 南方电网科学研究院有限责任公司 | Method for measuring damp degree of insulator surface dirt by using angular phase difference, and apparatus thereof |
-
2013
- 2013-12-13 CN CN201320830819.1U patent/CN203720266U/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105973941A (en) * | 2016-04-29 | 2016-09-28 | 南方电网科学研究院有限责任公司 | Method for measuring damp degree of insulator surface dirt by using angular phase difference, and apparatus thereof |
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|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20140716 |
|
| CX01 | Expiry of patent term |