CN204347229U - The calibrating installation of active leakage current tester - Google Patents
The calibrating installation of active leakage current tester Download PDFInfo
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- CN204347229U CN204347229U CN201520018585.XU CN201520018585U CN204347229U CN 204347229 U CN204347229 U CN 204347229U CN 201520018585 U CN201520018585 U CN 201520018585U CN 204347229 U CN204347229 U CN 204347229U
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Abstract
The utility model discloses a kind of calibrating installation of active leakage current tester, comprising: build-out resistor, sampling resistor, sampling module, current settings module and adjustment module; Wherein, build-out resistor comprises for the first mating end be connected with the positive input terminal of tested tester output voltage and the second mating end be connected with adjustment module; One end of sampling resistor is connected with the negative input end of tested tester output voltage, and the other end is connected with adjustment module; Sampling module, obtains sample rate current for carrying out sampling to the electric current flowed through on sampling resistor; Adjustment module, for the voltage of the second mating end being adjusted to equal with the voltage of the first mating end according to sample rate current with the deviation of the setting electric current that current settings module exports, ensure that sample rate current does not fluctuate with tester output voltage, the technical matters that the calibrating electric current solving active leakage current tester fluctuates with its output voltage, thus improve the stability of calibrating electric current, improve the precision of electric current calibrating.
Description
Technical field
The utility model relates to the measurement verification field of instrument and meter, especially, relates to a kind of calibrating installation of active leakage current tester.
Background technology
Leakage current and withstand voltage be electric apparatus safety specification test most important two contents.Leakage current tester is exactly the testing tool for measuring appliance leakage electric current, according to whether providing trial voltage, passive leakage current tester and active leakage current tester two class can be divided into, leakage current is a content the most basic of calibration to this two quasi-instrument and calibrating, and the utility model is mainly used in calibration and the calibrating of active leakage current tester leakage current.For active leakage current tester, the calibrating of leakage current adopts method as shown in Figure 1 usually, regulate the output voltage of tested tester, measure the pressure drop on known resistance with standard digital voltage table in (a), utilize Ohm law can calculating current actual value; Then directly can read the actual value of output current with standard digital reometer in (b).
The survey measurements stability dependency of this calibration method is in the stability of tested tester output voltage, usually directly powered by electrical network because tested tester exports, its stability generally has the fluctuation of more than 10%, and the class of accuracy of leakage current tester is generally 0.5 grade, directly alignment requirements cannot be met with the output of tested tester at all, when thus adopting said method calibrating, usually the cabinet opening tested tester is needed, disconnect the power supply that it exports, connect the high testing power supply of stability in addition and could meet test request, this makes this calibration method operate in actual applications to bother very much.In addition, owing to usually being had multiple range by test examination instrument, verification process needs for the different measuring resistance of different measurement range selection, and therefore, the method can not realize the automatic adjustment of normalized current, and it is adjustable to be difficult to realize calibrating current continuity.So need badly, exploitation is a kind of examines and determine electric current not with the calibrating installation of the active leakage current tester of active leakage current tester output voltage fluctuation.
Utility model content
The utility model provides a kind of calibrating installation of active leakage current tester, the technical matters fluctuated with active leakage current tester output voltage with the calibrating electric current solving active leakage current tester.
The technical solution adopted in the utility model is as follows:
A calibrating installation for active leakage current tester, comprising: build-out resistor, sampling resistor, sampling module, current settings module and adjustment module; Wherein,
Build-out resistor comprises for the first mating end be connected with the positive input terminal of tested tester output voltage and the second mating end be connected with adjustment module;
One end of sampling resistor is connected with the negative input end of tested tester output voltage, and the other end is connected with adjustment module;
Sampling module, for sampling to the electric current flowed through on sampling resistor and obtaining sample rate current;
Current settings module, for inputting different setting electric currents to adjustment module;
Adjustment module, comprises the first output terminal be connected with the second mating end and the second output terminal be connected with sampling resistor; Adjustment module, for being adjusted to equal with the voltage of the first mating end according to sample rate current with the deviation of setting electric current by the voltage of the second mating end.
Further, adjustment module also comprises amplitude modulation module and phase modulation module; Wherein,
Amplitude modulation module is for regulating the amplitude of the voltage of the second mating end equal with the amplitude of the voltage of the first mating end; Phase modulation module is for regulating the phase place of the voltage of the second mating end equal with the phase place of the voltage of the first mating end.
Further, amplitude modulation module comprises integrator and transformer; Wherein,
The reverse input end of integrator is connected with the output terminal of sampling module, and the positive input of integrator is connected with the output terminal of current settings module;
The one end on former limit of transformer is connected with the output terminal of integrator, and the other end connects zero potential; One end of the secondary of transformer is connected with the first output terminal of adjustment module, and the other end is connected with the second output terminal of adjustment module, and the second output terminal of adjustment module connects zero potential.
Further, phase modulation module comprises phase shift block and multiplier; Wherein,
Phase shift block, for carrying out phase shift to the voltage signal of the first mating end;
Multiplier, for the output signal of phase shift block sum-product intergrator being multiplied, and flows to transformer.
Further, phase modulation module also comprises sampling module, and sampling module is used for sampling the voltage signal of the first mating end of build-out resistor, and flows to phase shift block.
Further, amplitude modulation module also comprises power amplifier, and power amplifier is connected with transformer with multiplier, flows to transformer for the output signal of multiplier is carried out power amplification.
Further, integrator is proportional integrator or proportion integration differentiation device.
Further, proportional integrator comprises operational amplifier, electric capacity, the first resistance and the second resistance;
One end of first resistance is connected with the output terminal of sampling module, and the other end is connected with the reverse input end of operational amplifier;
One end of second resistance is connected with the output terminal of current settings module, and the other end is connected with the input end in the same way of operational amplifier;
Electric capacity is connected between the reverse input end of operational amplifier and output terminal.
Further, sampling module comprises AC/DC acquisition module and modular converter; Wherein,
AC/DC acquisition module is for gathering the sample rate current on sampling resistor;
Modular converter, for being converted to voltage signal by sample rate current.
The utility model has following beneficial effect:
The calibrating installation of the active leakage current tester of the utility model, comprise: build-out resistor, sampling resistor, sampling module, current settings module and adjustment module, wherein, adjustment module is used for being adjusted to by the voltage of the second mating end equal with the voltage of the first mating end according to sample rate current with the deviation of the setting electric current that current settings module exports, the output voltage stabilization of integrator can be made like this, thus make sample rate current be constantly equal to setting electric current, the technical matters that the calibrating electric current solving active leakage current tester fluctuates with active leakage current tester output voltage, thus improve the stability of calibrating electric current, improve the precision of electric current calibrating.
Except object described above, feature and advantage, the utility model also has other object, feature and advantage.Below with reference to figure, the utility model is described in further detail.
Accompanying drawing explanation
The accompanying drawing forming a application's part is used to provide further understanding of the present utility model, and schematic description and description of the present utility model, for explaining the utility model, is not formed improper restriction of the present utility model.In the accompanying drawings:
Fig. 1 is existing conventional active leakage current tester calibrating installation schematic diagram;
Fig. 2 is the active leakage current tester calibrating installation schematic diagram of the utility model preferred embodiment.
Reference numeral:
1, build-out resistor; 2, sampling resistor; 3, sampling module; 4, current settings module; 5, adjustment module; 6, tested tester; 7, integrator; 8, transformer; 9, phase shift block; 10, multiplier; 11, sampling module; 12, power amplifier; 13, operational amplifier; 14, electric capacity; 15, the first resistance; 16, the second resistance.
Embodiment
Below in conjunction with accompanying drawing, embodiment of the present utility model is described in detail, but the multitude of different ways that the utility model can be defined by the claims and cover is implemented.
As Fig. 2, preferred embodiment of the present utility model provides a kind of calibrating installation of active leakage current tester, comprising: build-out resistor 1, sampling resistor 2, sampling module 3, current settings module 4 and adjustment module 5; Wherein, build-out resistor 1 comprises for the first mating end be connected with the positive input terminal of tested tester 6 output voltage and the second mating end be connected with adjustment module 5; One end of sampling resistor 2 is connected with the negative input end of tested tester 6 output voltage, and the other end is connected with adjustment module 5; Sampling module 3, for sampling to the electric current flowed through on sampling resistor 2 and obtaining sample rate current; Current settings module 4, inputs different setting electric currents for giving adjustment module 5; Adjustment module 5, comprises the first output terminal be connected with the second mating end and the second output terminal be connected with sampling resistor 2; Adjustment module 5, for being adjusted to equal with the voltage of the first mating end according to sample rate current with the deviation of setting electric current by the voltage of the second mating end.
The present embodiment is by being adjusted to equal with the voltage of the first mating end according to sample rate current with the deviation of setting electric current by the voltage of the second mating end, sample rate current can be realized not with active leakage current tester output voltage fluctuation, the technical matters that the calibrating electric current solving active leakage current tester fluctuates with active leakage current tester output voltage, thus improve the stability of calibrating electric current, improve the precision of electric current calibrating.And the invention belongs to national science and technology supporting plan: the primary study content of typical first aid custodial care facility measurement standard and traceability system research (mission number: 2011BAI02B04), is significant.
Alternatively, adjustment module 5 also comprises amplitude modulation module and phase modulation module; Wherein, amplitude modulation module is for regulating the amplitude of the voltage of the second mating end equal with the amplitude of the voltage of the first mating end; Phase modulation module is for regulating the phase place of the voltage of the second mating end equal with the phase place of the voltage of the first mating end.
Alternatively, in the present embodiment, amplitude modulation module can comprise integrator 7 and transformer 8; Wherein, the reverse input end of integrator 7 is connected with the output terminal of sampling module 3, and the positive input of integrator 7 is connected with the output terminal of current settings module 4; The one end on the former limit of transformer 8 is connected with the output terminal of integrator 7, and the other end connects zero potential; One end of the secondary of transformer 8 is connected with the first output terminal of adjustment module 5, and the other end is connected with the second output terminal of adjustment module 5, and the second output terminal of adjustment module 5 connects zero potential.The present embodiment adopts integrator mainly based on the fast response characteristic of integral adjustment, in general, and the output voltage change of active leakage current tester 6, the i.e. voltage U of the first mating end
achange frequency is 50Hz, and the regulating frequency of integral adjustment is about 1600Hz, and therefore, amplitude modulation module is according to the voltage U of sample rate current with bias adjustment second mating end of setting electric current
bwith the voltage U of the first mating end
atime equal, the voltage U of the second mating end can be made
bchange can catch up with the voltage U of the first mating end rapidly
achange, thus make the stability of the calibrating electric current I flowing into tested tester 6 be better than the stability of its output voltage U.In the present embodiment, integrator 7 is proportional integrator or proportion integration differentiation device.Proportional integrator comprises operational amplifier 13, electric capacity 14, first resistance 15 and the second resistance 16; One end of first resistance 15 is connected with the output terminal of sampling module 3, and the other end is connected with the reverse input end of operational amplifier 13; One end of second resistance 16 is connected with the output terminal of current settings module 4, and the other end is connected with the input end in the same way of operational amplifier 13; Between the reverse input end that electric capacity 14 is connected to operational amplifier 13 and output terminal.
Alternatively, phase modulation module comprises phase shift block 9 and multiplier 10; Wherein, phase shift block 9, for carrying out phase shift to the voltage signal of the first mating end; Multiplier 10, for the output signal of phase shift block 9 sum-product intergrator 7 being multiplied, and flows to transformer 8.Phase shift block 9 in the present embodiment is mainly used in the voltage U to the first mating end
aenter horizontal phasing control, this is because transformer 8 is to the voltage U of the second mating end
bwhen regulating, certain phase offset can be produced, in order to regulate the voltage U of the second mating end
bwith the voltage U of the first mating end
aequal, the described voltage U generally first needed the first mating end
acarry out phase shift.Specifically can by the voltage U of the first mating end of sampling module 11 pairs of build-out resistors
asample, and flow to phase shift block 9, the voltage signal that sampled signal and the proportional integrator 7 through phase shift exports is flowed to multiplier 10 by phase shift block 9 again, and the output signal of phase shift block 9 sum-product intergrator 7 is multiplied by multiplier 10, flows to transformer 8.
Alternatively, amplitude modulation module also comprises power amplifier 13, and power amplifier 13 is connected with transformer 8 with multiplier 10, flows to transformer 8 for the output signal of multiplier 10 is carried out power amplification.The work being set to transformer 8 of power amplifier 13 provides enough drive singal.
Alternatively, sampling module 3 comprises AC/DC acquisition module and modular converter; Wherein, AC/DC acquisition module is for gathering the sample rate current on sampling resistor 2; Modular converter, for being converted to voltage signal by sample rate current.Similarly, current settings module 4 also includes modular converter, and for setting electric current is become voltage signal after conversion, thus the voltage signal after changing with sample rate current compares.
The specific works principle of the present embodiment is as follows:
To examine and determine 1mA current range, assuming that the output voltage of active leakage current tester is U=220V, get the resistance R of build-out resistor 1
0=200K, the no-load voltage ratio of transformer 8 is 1:40, the resistance R of the first resistance 15
1, the second resistance 16 resistance R
2be 1K, the C1 of electric capacity 14 is the resistance R of 100 μ F, sampling resistor 2
sfor 1K, sampling module 11 output voltage is 1V, and it is 0.90018V that current settings module 4 exports DC voltage, regulates the phase shift of phase shift block 9, until the voltage U of the second mating end
bwith the voltage U of the first mating end
aequal, be 220V, i.e. U
ab=0, now system balancing.Flow through the resistance R of sampling resistor 2
salternating current be 1mA.When the output voltage of active leakage current tester 6 is that U change causes flowing through R
selectric current when changing, the DC voltage then exported through sampling module 3 also changes, the 0.90018V voltage that its value and current settings module 4 export after voltage transitions produces difference, this difference is through integrator integration, form the difference signal amplified, this signal and the signal multiplication sampled after phase shift, obtain the drive singal of power amplifier 12, drive singal regulates the output voltage of power amplifier, thus changes the output voltage U of transformer 8
b, due to U
achange frequency be 50Hz, and proportional integral regulate regulating frequency be about 1600Hz, thus U
bchange can catch up with U rapidly
achange, make U
ab=0 can set up.
During system balancing, need satisfy condition:
the now output voltage of sampling module:
get R
1=R
2=1K, then, when current settings module 4 exports, operational amplifier 12 obtains stable output U
e.The sampling coefficient of sampling module 11 is K
1, phase shift block phase shift is
contrary with the phase shift angle of transformer 8, then phase shift block 9 exports U
ffor:
after multiplier 10 computing, obtain voltage U
gfor:
when power amplifier 12 enlargement factor is 1, then its output is
the no-load voltage ratio of transformer 8 is K
2, phase shift angle is
and
obtain voltage U
bfor:
regulation coefficient makes U
ek
1k
2=1, then U
a=U
bpermanent establishment.
In the present embodiment, work as U
aduring changes in amplitude:
can obtain
obviously, U
bfollow U
achange, and the U relevant to I
enot with U
achange, thus the stability of I is better than U.Can also be obtained by Fig. 1, sampling module output voltage is
when system balancing,
so,
due to U
dcan be set arbitrarily by current settings module 4, and R
sbe the value determined for fixing range, thus this active leakage current tester device can set different electric currents.So for the calibrating of different range, when being exported the voltage in certain limit by test examination instrument, the calibrating installation of active leakage current tester of the present utility model can be set by user, obtains continuously adjustable current value.Utilize the calibrating installation of active leakage current tester of the present utility model can directly use the output of tested tester and reach electric current calibrating accuracy requirement.
The foregoing is only preferred embodiment of the present utility model, be not limited to the utility model, for a person skilled in the art, the utility model can have various modifications and variations.All within spirit of the present utility model and principle, any amendment done, equivalent replacement, improvement etc., all should be included within protection domain of the present utility model.
Claims (9)
1. the calibrating installation of an active leakage current tester, it is characterized in that, comprising: build-out resistor (1), sampling resistor (2), sampling module (3), current settings module (4) and adjustment module (5); Wherein,
The second mating end that described build-out resistor (1) comprises the first mating end for being connected with the positive input terminal of tested tester (6) output voltage and is connected with described adjustment module (5);
One end of described sampling resistor (2) is connected with the negative input end of described tested tester (6) output voltage, and the other end is connected with described adjustment module (5);
Described sampling module (3), for sampling to the electric current flowed through on described sampling resistor (2) and obtain sample rate current;
Described current settings module (4), inputs different setting electric currents for giving described adjustment module (5);
Described adjustment module (5), comprises the first output terminal be connected with described second mating end and the second output terminal be connected with described sampling resistor (2); Described adjustment module (5) is for being adjusted to equal with the voltage of described first mating end according to described sample rate current with the deviation of described setting electric current by the voltage of described second mating end.
2. the calibrating installation of active leakage current tester according to claim 1, is characterized in that,
Described adjustment module (5) also comprises amplitude modulation module and phase modulation module; Wherein,
Described amplitude modulation module is for regulating the amplitude of the voltage of described second mating end equal with the amplitude of the voltage of described first mating end; Described phase modulation module is for regulating the phase place of the voltage of described second mating end equal with the phase place of the voltage of described first mating end.
3. the calibrating installation of active leakage current tester according to claim 2, is characterized in that,
Described amplitude modulation module comprises integrator (7) and transformer (8); Wherein,
The reverse input end of described integrator (7) is connected with the output terminal of described sampling module (3), and the positive input of described integrator (7) is connected with the output terminal of described current settings module (4);
The one end on the former limit of described transformer (8) is connected with the output terminal of described integrator (7), and the other end connects zero potential; One end of the secondary of described transformer (8) is connected with the first output terminal of described adjustment module (5), the other end is connected with the second output terminal of described adjustment module (5), and the second output terminal of described adjustment module (5) connects zero potential.
4. the calibrating installation of active leakage current tester according to claim 3, is characterized in that,
Described phase modulation module comprises phase shift block (9) and multiplier (10); Wherein,
Described phase shift block (9), for carrying out phase shift to the voltage signal of described first mating end;
Described multiplier (10), for the output signal of described phase shift block (9) with described integrator (7) being multiplied, and flows to described transformer (8).
5. the calibrating installation of active leakage current tester according to claim 4, is characterized in that,
Described phase modulation module also comprises sampling module (11), described sampling module (11) samples for the voltage signal of the first mating end to described build-out resistor (1), and flows to described phase shift block (9).
6. the calibrating installation of active leakage current tester according to claim 5, is characterized in that,
Described amplitude modulation module also comprises power amplifier (12), described power amplifier (12) is connected with described transformer (8) with described multiplier (10), flows to described transformer (8) for the output signal of described multiplier (10) is carried out power amplification.
7. the calibrating installation of active leakage current tester according to claim 6, is characterized in that,
Described integrator (7) is proportional integrator or proportion integration differentiation device.
8. the calibrating installation of active leakage current tester according to claim 7, is characterized in that,
Described proportional integrator comprises operational amplifier (13), electric capacity (14), the first resistance (15) and the second resistance (16);
One end of described first resistance (15) is connected with the output terminal of described sampling module (3), and the other end is connected with the reverse input end of described operational amplifier (13);
One end of described second resistance (16) is connected with the output terminal of described current settings module (4), and the other end is connected with the input end in the same way of described operational amplifier (13);
Between the reverse input end that described electric capacity (14) is connected to described operational amplifier (13) and output terminal.
9., according to the calibrating installation of the arbitrary described active leakage current tester of claim 1 to 8, it is characterized in that,
Described sampling module (3) comprises AC/DC acquisition module and modular converter; Wherein,
Described AC/DC acquisition module is for gathering the sample rate current on described sampling resistor (2);
Described modular converter, for being converted to voltage signal by described sample rate current.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520018585.XU CN204347229U (en) | 2015-01-12 | 2015-01-12 | The calibrating installation of active leakage current tester |
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|---|---|---|---|
| CN201520018585.XU CN204347229U (en) | 2015-01-12 | 2015-01-12 | The calibrating installation of active leakage current tester |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104535954A (en) * | 2015-01-12 | 2015-04-22 | 长沙天恒测控技术有限公司 | Calibration device of active leakage current tester |
| CN106841992A (en) * | 2017-02-16 | 2017-06-13 | 上海芯哲微电子科技股份有限公司 | A kind of DC/DC conversion arrangement for testing integrated circuit |
| CN108594148A (en) * | 2018-04-02 | 2018-09-28 | 辽宁省计量科学研究院 | Medical analysis for current leakage instrument calibrating installation and system |
| CN110412393A (en) * | 2018-04-28 | 2019-11-05 | 青岛仪迪电子有限公司 | Line build-out method for ac voltage withstanding test |
| CN110780250A (en) * | 2019-09-30 | 2020-02-11 | 国创新能源汽车能源与信息创新中心(江苏)有限公司 | Automatic calibration system and method for residual current detection |
-
2015
- 2015-01-12 CN CN201520018585.XU patent/CN204347229U/en not_active Withdrawn - After Issue
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104535954A (en) * | 2015-01-12 | 2015-04-22 | 长沙天恒测控技术有限公司 | Calibration device of active leakage current tester |
| CN104535954B (en) * | 2015-01-12 | 2017-05-03 | 长沙天恒测控技术有限公司 | Calibration device and method of active leakage current tester |
| CN106841992A (en) * | 2017-02-16 | 2017-06-13 | 上海芯哲微电子科技股份有限公司 | A kind of DC/DC conversion arrangement for testing integrated circuit |
| CN106841992B (en) * | 2017-02-16 | 2023-06-27 | 上海芯哲微电子科技股份有限公司 | Direct current/direct current conversion integrated circuit testing device |
| CN108594148A (en) * | 2018-04-02 | 2018-09-28 | 辽宁省计量科学研究院 | Medical analysis for current leakage instrument calibrating installation and system |
| CN110412393A (en) * | 2018-04-28 | 2019-11-05 | 青岛仪迪电子有限公司 | Line build-out method for ac voltage withstanding test |
| CN110412393B (en) * | 2018-04-28 | 2021-08-31 | 青岛仪迪电子有限公司 | Line compensation method for alternating current withstand voltage test |
| CN110780250A (en) * | 2019-09-30 | 2020-02-11 | 国创新能源汽车能源与信息创新中心(江苏)有限公司 | Automatic calibration system and method for residual current detection |
| CN110780250B (en) * | 2019-09-30 | 2021-11-09 | 国创移动能源创新中心(江苏)有限公司 | Automatic calibration system and method for residual current detection |
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Granted publication date: 20150520 Effective date of abandoning: 20170503 |