CN105093085A - Dual-impedance loop interference suppression device for partial discharge measuring instrument - Google Patents
Dual-impedance loop interference suppression device for partial discharge measuring instrument Download PDFInfo
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- CN105093085A CN105093085A CN201510563052.4A CN201510563052A CN105093085A CN 105093085 A CN105093085 A CN 105093085A CN 201510563052 A CN201510563052 A CN 201510563052A CN 105093085 A CN105093085 A CN 105093085A
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- measurement
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Abstract
The invention relates to a dual-impedance loop interference suppression device for a partial discharge measuring instrument, which comprises a power supply module and an interference suppression circuit. The interference suppression circuit comprises a first test loop and a second test loop. The first test loop comprises a first measurement impedor and to-be-tested equipment. The second test loop comprises a coupling capacitor and a second measurement impedor. The device further comprises a measurement and control module and a man-machine interaction module. The first measurement impedor and the second measurement impedor are the same in resistance value. The power supply module is connected with the first test loop and the second test loop. The measurement and control module and the man-machine interaction module are electrically connected. A voltage signal between a first connection point and a second connection point in the first test loop and the second test loop is outputted to the measurement and control module, so that the partial discharge quantity can be calculated.
Description
Technical field
The present invention relates to local discharge of electrical equipment detection technique field; Be specifically related to a kind of two impedance path interference rejection units for PD meter.
Background technology
As everyone knows, electrical equipment its insulating element that is in operation is subject to the impact of the various factors such as electricity, heat, machinery, poor environment, and insulating property can deterioration gradually, so that defect appears in apparatus insulated aspect, causes equipment failure.And the early detection fault that Insulation monitoring and diagnostic techniques can go wrong at insulation of electrical installation parts; Particularly shelf depreciation measuring technology is as the nondestructive measuring technology of one, is extensively used by people.Precisely and easily partial discharge test system is to ensureing that the safe operation of high voltage electric appliance quality and electric system is extremely important; Partial discharge test system product of the prior art is numerous and diverse various, Cleaning Principle also has multiple, for current the most common partial discharge test system of carrying out measuring based on pulse current method, its agent structure is all similar to the structure shown in accompanying drawing 1, further combined with accompanying drawing 1, partial discharge test system of the prior art mainly comprises without office's discharge source 01, step-up transformer 02, protection impedance 03, coupling capacitance 04, measurement impedance 05, PD meter 06 and embedded data process and control center 07; Described is electrically connected successively without office's discharge source 01, step-up transformer 02, protection impedance 03, coupling capacitance 04, measurement impedance 05 and PD meter 06; Described embedded data process and control center 07 are electrically connected respectively with without office's discharge source 01, step-up transformer 02 and PD meter 06.
Further combined with accompanying drawing 2, partial discharge test system of the prior art is when the insulating property of detecting electric equipment, although pass through the effect filtering of wave filter and the undesired signal of detected signal different frequency range in measure loop, still there is the interference current I with detected signal similar frequency bands
f2.The electrical equipment accepting to detect is equivalent to Cx in measure loop, the Zm in described measurement impedance and accompanying drawing 2, the actual office discharge stream I=V/Zm=I recorded
f2+ Ix, and just Ix, the I in measured current I required for us
f2be undesired signal, practice shows, above-mentioned undesired signal I
f2the impact of existence on test result larger, cause the signal to noise ratio (S/N ratio) of signal low, the measuring accuracy of whole test macro is not high.
In sum, be badly in need of at present wanting one can jamproof partial discharge test system.
Summary of the invention
The technical problem to be solved in the present invention is, provides one can anti-interference local discharge test macro.
For solving the problems of the technologies described above, the present invention proposes a kind of two impedance path interference rejection units for PD meter:
Power module, for providing power supply for proving installation;
Codan, for suppressing the undesired signal in circuit, comprises the first test loop and the second test loop;
First test loop, for loading Devices to test, produces discharge current;
Second test loop, for providing a circulation path for discharge current;
Described codan is for suppressing the undesired signal in circuit;
Include the first measurement impedance in described first test loop, the second test loop includes the second measurement impedance, and both impedances are equal;
Measurement & Control module, for survey bureau's electric discharge pressure; And
Human-computer interaction module, for display measurement result and provide interactive function.
Preferably, described first test circuit also comprises: Devices to test and the terminal for connecting Devices to test;
Wherein, Devices to test is received in the first test loop by connecting terminals, and described first measurement impedance is connected with Devices to test;
Described second test loop also comprises: coupling capacitance, and described second measurement impedance is connected with coupling capacitance.
Preferably, in described first test loop, one end of Devices to test splicing ear is electrically connected with the first measurement impedance, forms the first tie point; In described second test loop, one end of described coupling capacitance is electrically connected with the second measurement impedance, forms the second tie point; First tie point and the second tie point are connected to Measurement & Control module respectively.
Preferably, described Measurement & Control module is electrically connected with human-computer interaction module; By measuring the voltage between the first tie point and the second tie point, calculating office high-volume.
Preferably, calibration pulse generator is connected respectively to the two ends of the first measurement impedance, and is connected to sampling and control circuit.
Preferably, described digital frequency range of putting high-voltage power supply without office is 0 ~ 400Hz.。
Preferably, described power module is integral type structure, comprises digitally putting high-voltage power supply, protection impedance and calibration pulse generator without office in power module; Described digitally put high-voltage power supply without office externally export electric energy after protection impedance; Described calibration pulse generator is connected respectively to the first measurement impedance and Measurement & Control module.The power module adopted due to test macro of the prior art includes all quite huge step-up transformer of volume and weight, makes whole system volume and weight all very huge, the movement of equipment and attended operation complexity.The present invention adopts digitally puts high-voltage power supply without office and instead of all very huge step-up transformer of volume and weight, and the volume and weight of whole test macro is significantly declined, and the movement of test macro and attended operation become simpler.
Preferably, described Measurement & Control module is integral type structure, comprises sampling and control circuit, the first wave filter and the second wave filter in Measurement & Control module; Described first wave filter is connected to described first tie point; Described second connector is connected to described second tie point.This structure optimizes the structure of whole test macro further, makes each parts combine formation module as much as possible, makes the I&M of test macro more convenient.
Preferably, calibration pulse generator is connected respectively to the two ends of the first measurement impedance, and is connected to sampling and control circuit.
As preferably, described human-computer interaction module is PC.The human-computer interaction module adopted due to test macro of the prior art remains embedded data disposal system, it is low to there is product integrated level in this system, function is simple, the weak point of the setting that user is in use correlated with and debugging operations complexity, through making repeated attempts and comparing discovery, the present invention directly adopts PC with windowing operation system as human-computer interaction module, because PC has powerful processor, Windowing man-machine interaction is also more directly perceived, PC also has the data subsequent treatment function of intensity simultaneously, if directly carry out data analysis, make chart, PowerPoint etc., in sum, this preference substantially increases the integrated level of product, product function is also abundanter, the setting that user is in use correlated with and debugging operations more simple and clear.
As preferably, what described PC adopted is Windows operating system.Windows operating system has very powerful user base, and user does not substantially need to carry out extra training and gets final product left-hand seat, so adopt the test macro versatility of Windows operating system more excellent.
As further preferably, described digital frequency range of putting high-voltage power supply without office is 0 ~ 400HZ.The frequency that power supply of the prior art can cover is rather narrow, device under test poor for applicability, the employing digital power of therefore the invention be 0 ~ 400HZ by the frequency optimization of power supply, and this frequency range can be suitable for various Devices to test substantially.
According to a further aspect in the invention, provide a kind of method utilizing said apparatus to carry out shelf depreciation test, it is characterized in that, described method comprises: Partial discharge signal disturbs i with in frequency band
fflow through the first test loop and the second test loop respectively, in described first test loop, Devices to test equivalent capacity is C
x, in described second test loop, coupling capacitance is C
k; Office discharge stream i
xthrough Devices to test equivalent capacity C
x, coupling capacitance C
kand the first measurement impedance Z
m1with the second measurement impedance Z
m2, on the first measurement impedance and the second measurement impedance, produce pressure drop v respectively
x1and v
x2, wherein: measurement impedance Z
mthen be designated as the first measurement impedance and the second measurement impedance sum; Through filter and amplification signal transacting, A/D sampling uploads to PC or other data handling system process, calculates striking out high-volume by PC according to the computing formula preset.
More excellent: office's concrete computing formula is high-volume as follows: office is V high-volume
xsize and i
xbe directly proportional:
v
x＝v
x2-v
x1
Further
v
x＝z
m[2i
x+(i
f2-i
f1)]，
Interference current is (i
f2-i
f1), wherein, i
f1represent the interference current component flowing through Devices to test, i
f2represent the interference current component flowing through coupling capacitance, interference current receives effective suppression.
More excellent: the interference current that the first measurement impedance on loop, Devices to test splicing ear place flows through is contrary with the direction of the interference current that the second measurement impedance on loop, coupling capacitance place flows through, interference current is cancelled out each other a part.
In addition, present invention is disclosed a kind of office and put test macro, comprise described pair of impedance path interference rejection unit.
After adopting technique scheme, the present invention has following beneficial effect: the invention by single impedance single loop measuring system of the prior art, be improved to two impedance two-circuits measuring system, in test process, the interference current that measurement impedance on loop, Devices to test splicing ear place produces is contrary with the direction of the interference current that the measurement impedance on loop, coupling capacitance place produces, interference current has been cancelled out each other a part, effectively suppressed, the design in two impedance measurement loop simultaneously, make this invention system the office that tests put 2 times that voltage signal is the voltage signal of single impedance path in prior art, namely useful signal is exaggerated, undesired signal is suppressed, the signal to noise ratio (S/N ratio) of naturally whole measuring system improves greatly, measuring accuracy is also higher.
Accompanying drawing explanation
Fig. 1 is the structure square frame simplified schematic diagram of partial discharge test system in prior art;
Fig. 2 is the basic test circuit diagram of partial discharge test system in prior art;
Fig. 3 is the structure block diagram of the two impedance path interference rejection unit of the present invention;
Fig. 4 is the basic test circuit diagram of the two impedance path interference rejection unit of the present invention.
As shown in Figure 1, 2: in prior art: 01, without office's discharge source, 02, step-up transformer, 03, protection impedance, 04, coupling capacitance, 05, measurement impedance, 06, PD meter, 07, embedded data process and control center.
As shown in Figure 3,4, in the present invention: 1, power module, the 2, first measurement impedance; 3, the second measurement impedance, 4, coupling capacitance, 5, Devices to test splicing ear; 6, Measurement & Control module, 7, PC, 8, digitally put high-voltage power supply without office; 9, impedance is protected; 10, calibration pulse generator, 11, sampling and control circuit, the 12, first wave filter; 13, the second wave filter, 14, Devices to test.
Embodiment
Below in conjunction with accompanying drawing 1 to 4, the present invention is described in further detail.
By reference to the accompanying drawings 3 and accompanying drawing 4, a kind of two impedance path interference rejection units for PD meter, comprising power module 1 for providing power supply for proving installation, also comprising measurement impedance, coupling capacitance 4, Devices to test splicing ear 5, Measurement & Control module 6 and human-computer interaction module; Described measurement impedance comprises the first equal measurement impedance 2 and the second measurement impedance 3 of resistance value; Codan, for suppressing the undesired signal in circuit, comprise the first test loop and the second test loop, in first test loop, one end of Devices to test splicing ear 5 is electrically connected with the first measurement impedance 2 and Measurement & Control module 6 respectively, and form the first tie point, the other end is connected to power module 1, first test loop, for loading Devices to test, produces discharge current; Described power module 1 is electrically connected with coupling capacitance 4 and Devices to test splicing ear 5 respectively; In second test loop, one end of described coupling capacitance 4 is electrically connected with the second measurement impedance 3 and Measurement & Control module 6 respectively, and form the second tie point, the other end is connected to power module 1, and the second test loop is used for providing a circulation path for discharge current; First measurement impedance 2 and the second measurement impedance 3 are all electrically connected with power module 1, and both impedances are equal; Described Measurement & Control module 6 is electrically connected with human-computer interaction module; By measuring the voltage between the first tie point and the second tie point, further calculating office high-volume.
After adopting said structure, the present invention has following beneficial effect: the invention by single impedance single loop measuring system of the prior art, be improved to two impedance two-circuits measuring system, in test process, the interference current that measurement impedance on loop, Devices to test splicing ear 5 place produces is contrary with the direction of the interference current that the measurement impedance on loop, coupling capacitance 4 place produces, interference current has been cancelled out each other a part, effectively suppressed, the design in two impedance measurement loop simultaneously, make this invention system the office that tests put 2 times that voltage signal is the voltage signal of single impedance path in prior art, namely useful signal is exaggerated, undesired signal is suppressed, the signal to noise ratio (S/N ratio) of naturally whole measuring system improves greatly, measuring accuracy is also higher.
Further combined with accompanying drawing 4, carry out quantitative test to beneficial effect of the present invention, as can be seen from the figure, Partial discharge signal disturbs i with in frequency band
fflow through test product C respectively
x[i.e. Devices to test equivalent capacity, test product and Devices to test] and coupling capacitance C
karticle two, loop; And office discharge stream i
xthrough test product, coupling capacitance and measurement impedance Z
m, on the first measurement impedance and the second measurement impedance, produce pressure drop v respectively
x1and v
x2; Through signal transacting such as filter and amplifications, A/D sampling uploads to PC or other data handling system process, calculates striking out high-volume by PC according to the computing formula preset.
Concrete computing formula is as follows: office's size high-volume and i
xbe directly proportional, traditional method is single measurement impedance, and namely not having the first measurement impedance in circuit diagram, is according to v
x2=Z
m.(i
x+ i
f2) office of calculating high-volume; And the present invention is two impedance path v
x=v
x2-v
x1, further v
x=z
m[2i
x+ (i
f2-i
f1)], both contrasts can find, when same office's discharge stream, it is traditional 2 times that voltage signal is put in the office of this invention; Analyze further, interference current receives effective suppression again, and traditional interference current is i
f2, and this invention is (i
f2-i
f1), clearly, signal to noise ratio (S/N ratio) improves greatly.
In sum, the invention provides the partial discharge test system that a kind of measuring accuracy is higher, comprise aforesaid pair of impedance path interference rejection unit.
As preferably, described human-computer interaction module is PC 7.Because applicant finds that the human-computer interaction module that test macro of the prior art adopts remains embedded data disposal system, it is low to there is product integrated level in this system, function is simple, the weak point of the setting that user is in use correlated with and debugging operations complexity, applicant is through making repeated attempts and comparing discovery, direct employing with the PC of windowing operation system as human-computer interaction module, because PC has powerful processor, Windowing man-machine interaction is also more directly perceived, PC also has the data subsequent treatment function of intensity simultaneously, if directly carry out data analysis, make chart, PowerPoint etc., in sum, this preference substantially increases the integrated level of product, product function is also abundanter, the setting that user is in use correlated with and debugging operations more simple and clear.
As preferably, described power module 1 is integral type structure, comprises digitally putting high-voltage power supply 8, protection impedance 9 and calibration pulse generator 10 without office in power module 1; Described digitally put high-voltage power supply 8 without office externally export electric energy after protection impedance 9; Described calibration pulse generator 10 is electrically connected with the first measurement impedance 2 and Measurement & Control module 6 respectively.Because applicant also finds that the power module that test macro of the prior art adopts includes all quite huge step-up transformer of volume and weight, make whole system volume and weight all very huge, the movement of equipment and attended operation complexity.Through the further innovation of applicant, adopt and digitally put high-voltage power supply 8 without office and instead of all very huge step-up transformer of volume and weight, the volume and weight of whole test macro is significantly declined, and the movement of test macro and attended operation become simpler.
As preferably, described Measurement & Control module 6 is integral type structure, comprises sampling and control circuit 11, first wave filter 12 and the second wave filter 13 in Measurement & Control module 6; The first described wave filter 12 and the second wave filter 13 are all electrically connected with control circuit 11 with sampling, and the first described wave filter 12 is electrically connected with the electric signal input end of the first measurement impedance 2 simultaneously; The second described wave filter 13 is electrically connected with the electric signal input end of the second measurement impedance 3 simultaneously.This structure optimizes the structure of whole test macro further, makes each parts combine formation module as much as possible, makes the I&M of test macro more convenient.
As preferably, what described PC 7 adopted is Windows operating system.Windows operating system has very powerful user base, and user does not substantially need to carry out extra training and gets final product left-hand seat, so adopt the test macro versatility of Windows operating system more excellent.
As further preferably, described digital frequency range of putting high-voltage power supply 8 without office is 0 ~ 400HZ.The frequency that power supply of the prior art can cover is rather narrow, device under test poor for applicability, therefore the creationary employing digital power of applicant be 0 ~ 400HZ by the frequency optimization of power supply, and this frequency range can be suitable for various Devices to test substantially.
Be described the present invention and embodiment thereof above, this description does not have restricted, and shown in accompanying drawing is also one of embodiments of the present invention, and actual structure is not limited thereto.If generally speaking those of ordinary skill in the art enlightens by it, when not departing from the invention aim, designing the frame mode similar to this technical scheme and embodiment without creationary, all should protection scope of the present invention be belonged to.
Claims (9)
1., for two impedance path interference rejection units for PD meter, it is characterized in that this device comprises:
Power module, for providing power supply for proving installation;
Codan, for suppressing the undesired signal in circuit, comprises the first test loop and the second test loop;
First test loop, for loading Devices to test, produces discharge current;
Second test loop, for providing a circulation path for discharge current;
Described codan is for suppressing the undesired signal in circuit;
Include the first measurement impedance in described first test loop, the second test loop includes the second measurement impedance, and both impedances are equal;
Measurement & Control module, for survey bureau's electric discharge pressure; And
Human-computer interaction module, for display measurement result and provide interactive function.
2. according to claim 1 pair of impedance path interference rejection unit, is characterized in that, preferred:
Described first test circuit also comprises: Devices to test and the terminal for connecting Devices to test;
Wherein, Devices to test is received in the first test loop by connecting terminals, and described first measurement impedance is connected with Devices to test;
Described second test loop also comprises: coupling capacitance, and described second measurement impedance is connected with coupling capacitance.
3. according to claim 1 pair of impedance path interference rejection unit, is characterized in that: in described first test loop, and one end of Devices to test splicing ear is electrically connected with the first measurement impedance, forms the first tie point; In described second test loop, one end of described coupling capacitance is electrically connected with the second measurement impedance, forms the second tie point; First tie point and the second tie point are connected to Measurement & Control module respectively.
4. according to claim 2 pair of impedance path interference rejection unit, is characterized in that:
Described Measurement & Control module is electrically connected with human-computer interaction module; By measuring the voltage between the first tie point and the second tie point, calculating office high-volume.
5. according to claim 1 pair of impedance path interference rejection unit, is characterized in that:
Described power module is integral type structure;
Comprise in described power module and digitally put high-voltage power supply, protection impedance and calibration pulse generator without office; Described digitally put high-voltage power supply without office externally export electric energy after protection impedance; Described calibration pulse generator is connected respectively to the first measurement impedance and Measurement & Control module.
6. according to claim 5 pair of impedance path interference rejection unit, is characterized in that: described Measurement & Control module is integral type structure, comprises sampling and control circuit, the first wave filter and the second wave filter in Measurement & Control module; Described first wave filter is connected to described first tie point; Described second connector is connected to described second tie point.
7. according to claim 6 pair of impedance path interference rejection unit, is characterized in that: calibration pulse generator is connected respectively to the two ends of the first measurement impedance, and is connected to sampling and control circuit.
8. according to claim 6 pair of impedance path interference rejection unit, is characterized in that: described digital frequency range of putting high-voltage power supply without office is 0 ~ 400Hz.
9. according to claim 3 pair of impedance path interference rejection unit, is characterized in that: Partial discharge signal disturbs i with in frequency band
fflow through the first test loop and the second test loop respectively, described Devices to test equivalent capacity is C
x, coupling capacitance is C
k; Office discharge stream i
xthrough Devices to test equivalent capacity C
x, coupling capacitance C
kand the first measurement impedance Z
m1with the second measurement impedance Z
m2, on the first measurement impedance and the second measurement impedance, produce pressure drop v respectively
x1and v
x2, wherein: measurement impedance Z
mthen be designated as the first measurement impedance and the second measurement impedance sum;
Through filter and amplification signal transacting, A/D sampling uploads to PC or other data handling system process, calculates striking out high-volume by PC according to the computing formula preset.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510563052.4A CN105093085A (en) | 2015-09-07 | 2015-09-07 | Dual-impedance loop interference suppression device for partial discharge measuring instrument |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510563052.4A CN105093085A (en) | 2015-09-07 | 2015-09-07 | Dual-impedance loop interference suppression device for partial discharge measuring instrument |
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| CN105093085A true CN105093085A (en) | 2015-11-25 |
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| CN201510563052.4A Pending CN105093085A (en) | 2015-09-07 | 2015-09-07 | Dual-impedance loop interference suppression device for partial discharge measuring instrument |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11304871A (en) * | 1998-04-16 | 1999-11-05 | Nissin Electric Co Ltd | Insulator contamination detecting apparatus |
| CN1580797A (en) * | 2004-05-17 | 2005-02-16 | 西安交通大学 | Power cable local discharge on-line monitoring method and device |
| CN101004436A (en) * | 2007-01-22 | 2007-07-25 | 西南交通大学 | High senitive system for detecting local discharging of high voltage electric power equipment with large capacity |
| CN204479706U (en) * | 2015-04-03 | 2015-07-15 | 王宁 | Digitizing wideband partial discharge test system |
| CN205317894U (en) * | 2015-09-07 | 2016-06-15 | 湖南银河天涛科技有限公司 | A two impedance return circuit interference rejection unit for appearance is put in office |
-
2015
- 2015-09-07 CN CN201510563052.4A patent/CN105093085A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11304871A (en) * | 1998-04-16 | 1999-11-05 | Nissin Electric Co Ltd | Insulator contamination detecting apparatus |
| CN1580797A (en) * | 2004-05-17 | 2005-02-16 | 西安交通大学 | Power cable local discharge on-line monitoring method and device |
| CN101004436A (en) * | 2007-01-22 | 2007-07-25 | 西南交通大学 | High senitive system for detecting local discharging of high voltage electric power equipment with large capacity |
| CN204479706U (en) * | 2015-04-03 | 2015-07-15 | 王宁 | Digitizing wideband partial discharge test system |
| CN205317894U (en) * | 2015-09-07 | 2016-06-15 | 湖南银河天涛科技有限公司 | A two impedance return circuit interference rejection unit for appearance is put in office |
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Application publication date: 20151125 |