CN204065388U - A kind of Secondary Circuit of Potential Transformer pressure drop wireless detection device - Google Patents
A kind of Secondary Circuit of Potential Transformer pressure drop wireless detection device Download PDFInfo
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- CN204065388U CN204065388U CN201420147418.0U CN201420147418U CN204065388U CN 204065388 U CN204065388 U CN 204065388U CN 201420147418 U CN201420147418 U CN 201420147418U CN 204065388 U CN204065388 U CN 204065388U
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Abstract
The utility model discloses a kind of Secondary Circuit of Potential Transformer pressure drop wireless detection device, comprise a main frame (3) and a slave (4); Main frame (3) comprises main frame measurement module (15), main frame external antenna (7), hosi wireless communication module (11), host data processing module (9), host display (13) and main frame gps time synchronization module (5).Slave (4) comprises slave measurement module (16), slave external antenna (8), slave wireless communication module (12), slave data processing module (10), slave display (14) and slave gps time synchronization module (6).The utility model is without the need to connecting secondary cable, reasonable in design, multiple functional, and intelligence degree is high, detection data are accurate, easy to carry, and can meet the request for utilization of code, improve experimental safe and reliability, alleviate work on the spot amount, largely increase work efficiency and quality.
Description
Technical field
The utility model belongs to power domain, particularly relates to the pick-up unit of a kind of wireless measurement Secondary Circuit of Potential Transformer pressure drop.
Background technology
The error that electric energy metering error is caused by the resultant error of mutual inductor, the error of electric energy meter and Secondary Circuit of Potential Transformer pressure drop forms.In these factors, the impact of Secondary Circuit of Potential Transformer pressure drop is often comparatively serious.Voltage transformer (VT) in electric power meter usually and electric energy meter distant, larger secondary load electric current and secondary circuit impedance cause the amplitude of voltage transformer secondary terminal voltage and electric power meter end voltage and phase place inconsistent, affect the accurate, just of electric energy metrical.Secondary Circuit of Potential Transformer pressure drop, as the part forming error in dipping, is subject to extensive concern, has strict monitoring, control criterion both at home and abroad.Regulation in domestic industry standard DL/T448-2000 " electric power meter technical management code ": the Voltage Transformer Secondary Circuit Voltage Drop that I, II class is used in the electric power meter of trade settlement should be not more than 0.2 of its rated secondary voltage, in other electric power meter, voltage transformer secondary electricity loop pressure drop should be not more than 0.5 of its rated secondary voltage; Periodic detection is answered in operating Secondary Circuit of Potential Transformer pressure drop, and general provision sense cycle is 2 years.Therefore, be necessary that research is accurate, safety, efficiently measuring method and device.
Because Secondary Circuit of Potential Transformer pressure drop is on the appreciable impact of electric energy metrical, research sums up multiple voltage transformer secondary circuit drop measurement method both at home and abroad for a long time, mainly contains mutual-inductor tester method, in a small amount limit for height internal resistance voltmeter method, phase voltammetric meter method, pin-point accuracy voltmeter method, load relative method etc.The each tool relative merits of these methods, can be divided into the indirect method of measurement and the large class of the direct method of measurement two according to measuring principle.
The measuring object of the indirect method of measurement is voltage transformer (VT) terminal voltage U
tVwith electric power meter end voltage U
whmeasure and carry out at two ends, according to formula 100% × (U simultaneously
tV-U
wh)/U
tVcalculate the ratio difference of both end voltage, this method measuring process is simple, safety, but generally can only obtain ratio difference, phase differential can not be obtained, although the wireless monitoring instrument method of current use can measure ratio difference and phase differential, be subject to technical limitation, its accuracy of measurement does not reach requirement.
The direct method of measurement adopts error of measurement principle, the phasor difference △ U of measured mainly voltage transformer (VT) terminal voltage and electric power meter end voltage, and this method has higher accuracy, less demanding to surveying instrument, and instrument cost is low.But require between voltage transformer (VT) terminal voltage and electric power meter end voltage, there is auxiliary direct electrical connection, need during measurement to lay interim test cable, operate relatively loaded down with trivial details, the more important thing is that the direct method of measurement exists more potential safety hazard.The method and device are as the representative of the direct method of measurement, and based on error of measurement principle, current most widely used general, the method mainly exists following problem:
(1) test cable Long-Time Service, insulation ag(e)ing or damage, may short circuit be caused: and easily there is the situations such as damaged and fracture in the cable laid, cause signal transmission distortion, inefficacy, threaten testing equipment and personnel's personal safety: meanwhile, if voltage transformer (VT) terminal voltage and electric power meter end voltage distances are far, longer cable need be laid and connect voltage transformer secondary end and electric power meter end, thus introduce additive error, make error information misalignment;
(2) site environment is complicated, and the test cable laid passes through stair, buildings, public passage, raceway groove, door and window, trees etc. possibly, and cable insulation is easily scratched, weares and teares, and causes short circuit;
(3) comparatively large to the surveying work amount of some long distance loops, safety custody difficulty.
Summary of the invention
In view of this, the technical problems to be solved in the utility model is to provide a kind of Secondary Circuit of Potential Transformer pressure drop wireless detection device, to realize carrying out Measurement accuracy and calibration to Secondary Circuit of Potential Transformer pressure drop when the connection without the need to secondary cable.
A kind of Secondary Circuit of Potential Transformer pressure drop wireless detection device, comprises a main frame and a slave; Main frame by host data processing module respectively with main frame measurement module, hosi wireless communication module, host display and main frame gps time synchronization module, wherein main frame measurement module is connected with voltage transformer secondary end by secondary cable, and hosi wireless communication module is connected with main frame external antenna; Slave is connected with slave measurement module, slave wireless communication module, slave display and slave gps time synchronization module respectively by slave data processing module; Wherein slave measurement module is connected with electric power meter end by secondary cable, and slave wireless communication module is connected with slave external antenna; By hosi wireless communication module and the wireless connections of slave wireless communication module between main frame and slave.
The utility model host data processing module, use the amplitude of Signal Pretreatment algorithm, least square method and accurate synchronization discrete fourier algorithm acquisition measured signal, frequency and phase information, for more described main frame digital signal and described slave digital signal, draw voltage error and phase differential, and send clock synchronous instruction and make main frame digital signal and slave digital signal synchronous, realize voltage transformer secondary end 1 synchronous with electric power meter end 2 signal.
The utility model host display, is connected with host data processing module, for simultaneous display voltage error and phase differential; Described slave display, is connected with slave data processing module, for simultaneous display voltage error and phase differential.Preferably meet-40 DEG C ~ 70 DEG C military liquid crystal display of wide temperature that national military standard GJB4 and GJB151A requires, so that can in Northeast China extreme cold area and the outdoor use in area of Hainan hot humid.
The utility model main frame gps time synchronization module and slave gps time synchronization module, for the synchronous universal time of receiving satellite signal.Special gps time module MOTORO VP ONCORE 50ns (1 σ) that preferred motorola inc produces.
Main frame measurement module, for Measurement accuracy voltage transformer secondary end electric parameter signal, and is converted to main frame digital signal by A/D.
Slave measurement module, for Measurement accuracy electric power meter end electric parameter signal, and is converted to slave digital signal by A/D.
Slave wireless communication module, for converting the slave digital signal of reception to wireless communication signals, then sends hosi wireless communication module to.
Hosi wireless communication module, for the described wireless communication signals received is reduced into slave digital signal, then is sent to described host data processing module by described slave digital signal.
Host data processing module, for more described main frame digital signal and described slave digital signal, draw voltage error and phase differential, and send clock synchronous instruction and make main frame digital signal and slave digital signal synchronous, realize voltage transformer secondary end synchronous with electric power meter end signal.
Slave data processing module, for receive and process slave measurement module surveys electric power meter end electric parameter digital signal, and sends clock synchronous instruction according to host data processing module, realizes main frame digital signal and slave digital signal is synchronous.
Host display, for simultaneous display voltage error and phase differential.
Slave display, for simultaneous display voltage error and phase differential.
Main frame external antenna, for sending and receiving wireless communication signals.
Slave external antenna, for sending and receiving wireless communication signals.
The beneficial effects of the utility model are: the Secondary Circuit of Potential Transformer pressure drop wireless detection device adopting technique scheme, without the need to connecting secondary cable, thus reduce false wiring and the damaged probability of wire, reasonable in design, multiple functional, intelligence degree is high, detection data are accurate, easy to carry, and the request for utilization of code can be met, improve experimental safe and reliability, alleviate work on the spot amount, largely increase work efficiency and quality, and provide important references for the development of same category of device application, design, improvement.
Accompanying drawing explanation
Fig. 1 is the utility model apparatus structure schematic diagram;
Fig. 2 is main frame gps time synchronization module described in the utility model and slave gps time synchronization module schematic diagram.
Embodiment
The utility model is described in detail below in conjunction with accompanying drawing.
A kind of Secondary Circuit of Potential Transformer pressure drop wireless detection device, comprises a main frame 3 and a slave 4; Described main frame 3 by host data processing module 9 respectively with main frame measurement module 15, hosi wireless communication module 11, host display 13 and main frame gps time synchronization module 5, wherein main frame measurement module 15 is connected with voltage transformer secondary end 1 by secondary cable 17, and hosi wireless communication module 11 is connected with main frame external antenna 7; Described slave 4 is connected with slave measurement module 16, slave wireless communication module 12, slave display 14 and slave gps time synchronization module 6 respectively by slave data processing module 10; Wherein slave measurement module 16 is connected with electric power meter end 2 by secondary cable 18, and slave wireless communication module 12 is connected with slave external antenna 8; By hosi wireless communication module 11 and slave wireless communication module 12 wireless connections between main frame 3 and slave 4.
Described main frame measurement module 15, for Measurement accuracy voltage transformer secondary end electric parameter signal, and is converted to main frame digital signal by A/D.
Described slave measurement module 16, for Measurement accuracy electric power meter end electric parameter signal, and is converted to slave digital signal by A/D.
Described slave wireless communication module 12 is connected by wireless communication signals with hosi wireless communication module 11.
Described slave wireless communication module 12, for converting the slave digital signal of reception to wireless communication signals, then sends hosi wireless communication module 11 to.
Described hosi wireless communication module 11, for the described wireless communication signals received is reduced into slave digital signal, then is sent to described host data processing module 9 by described slave digital signal.
Described host data processing module 9, use the amplitude of Signal Pretreatment algorithm, least square method and accurate synchronization discrete fourier algorithm acquisition measured signal, frequency and phase information, for more described main frame digital signal and described slave digital signal, draw voltage error and phase differential, and send clock synchronous instruction and make main frame digital signal and slave digital signal synchronous, realize voltage transformer secondary end 1 synchronous with electric power meter end 2 signal.
Described slave data processing module 10, for receive and process slave measurement module 16 survey electric power meter end 2 electric parameter digital signal, and send clock synchronous instruction according to host data processing module 9, realize main frame digital signal and slave digital signal is synchronous.
Described host display 13, be connected with host data processing module 9, for simultaneous display voltage error and phase differential, preferably meet national military standard GJB4 and GJB151A requirement,-40 DEG C ~ 70 DEG C military liquid crystal display of wide temperature, so that can in Northeast China extreme cold area and the outdoor use in area of Hainan hot humid.
Described slave display 14, be connected with slave data processing module 10, for simultaneous display voltage error and phase differential, preferably meet national military standard GJB4 and GJB151A requirement,-40 DEG C ~ 70 DEG C military liquid crystal display of wide temperature, so that can in Northeast China extreme cold area and the outdoor use in area of Hainan hot humid.
Described main frame external antenna 7, is connected with hosi wireless communication module 11, for sending and receiving wireless communication signals.
Described slave external antenna 8, is connected with slave wireless communication module 12, for sending and receiving wireless communication signals.
Described main frame gps time synchronization module 5 and slave gps time synchronization module 6, receiving satellite signal, for synchronous universal time, and the universal time corresponding with pulse front edge of the pulse signal of output gap 1s (1pps) and serial ports output and date code (year, month, day, hour, min, second) are to described host data processing module 9 and slave data processing module 10.The accuracy of measuring requirement due to voltage transformer secondary voltage drop is higher, and General Requirements gps clock error is no more than 100ns ~ 200ns.Special gps time module MOTORO VP ONCORE 50ns (1 σ) that preferred motorola inc produces, its implication is: clocking error is normal distribution, and in the probability interval of 1 σ, time clock error is less than 50ns.
As shown in Figure 1, during the work of the utility model Secondary Circuit of Potential Transformer pressure drop wireless detection device, first MOTORO VP ONCORE 50ns (1 σ) the main frame gps time synchronization module 5 preferred for the utility model motorola inc produced and the target setting of slave gps time synchronization module 6 time precision are " position is fixed " pattern, and its principle of work as shown in Figure 2.Main frame gps time synchronization module 5 and slave gps time synchronization module 6 pass through the pulse signal (1pps) of output gap 1s and the universal time corresponding with pulse front edge of serial ports output and date code (year, month, day, hour, min, second) to host data processing module 9 and slave data processing module 10, make main frame 3 and slave 4 be synchronized to universal time, and main frame 3 and slave 4 clocking error can be made to be less than 50ns.
Then, voltage transformer secondary end 1 is received on main frame measurement module 15 by secondary cable 17; Electric power meter end 2 is received on slave measurement module 16 by secondary cable 18; Main frame measurement module 15 for Measurement accuracy voltage transformer secondary end electric parameter signal, and is converted to main frame digital data transmission to host data processing module 9 by A/D.Slave measurement module 16, for Measurement accuracy electric power meter end electric parameter signal, and is converted to slave digital data transmission to slave data processing module 10 by A/D.
The slave digital signal that slave measurement module 16 sends by slave data processing module 10 is sent to slave wireless communication module 12; Slave wireless communication module 12 converts the slave digital signal of reception to wireless communication signals, then sends hosi wireless communication module 11 to.The described wireless communication signals received is reduced into slave digital signal by hosi wireless communication module 11, more described slave digital signal is sent to described host data processing module 9.Host data processing module 9, use the amplitude of Signal Pretreatment algorithm, least square method and accurate synchronization discrete fourier algorithm acquisition measured signal, frequency and phase information, for more described main frame digital signal and described slave digital signal, draw voltage error and phase differential.And send clock synchronous instruction to hosi wireless communication module 11 and reach slave wireless communication module 12 and arrive slave data processing module 10, make main frame digital signal and slave digital signal synchronous, realize voltage transformer secondary end 1 synchronous with electric power meter end 2 signal.
Finally, be connected with host data processing module 9 by host display 13, for simultaneous display voltage error and phase differential.Slave display 14 is connected with slave data processing module 10, for simultaneous display voltage error and phase differential.
The Secondary Circuit of Potential Transformer pressure drop wireless detection device that the utility model provides is without the need to connecting secondary cable, thus reduce false wiring and the damaged probability of wire, and the request for utilization of code can be met, improve experimental safe and reliability, alleviate work on the spot amount, largely increase work efficiency and quality, and provide reference for the development of same category of device application, design, improvement.
Claims (1)
1. a Secondary Circuit of Potential Transformer pressure drop wireless detection device, is characterized in that, comprises a main frame (3) and a slave (4); Main frame (3) is connected with main frame measurement module (15), hosi wireless communication module (11), host display (13) and main frame gps time synchronization module (5) respectively by host data processing module (9), wherein main frame measurement module (15) is connected with voltage transformer secondary end (1) by secondary cable (17), and hosi wireless communication module (11) is connected with main frame external antenna (7); Slave (4) is connected with slave measurement module (16), slave wireless communication module (12), slave display (14) and slave gps time synchronization module (6) respectively by slave data processing module (10); Wherein slave measurement module (16) is connected with electric power meter end (2) by secondary cable (18), and slave wireless communication module (12) is connected with slave external antenna (8); By hosi wireless communication module (11) and slave wireless communication module (12) wireless connections between main frame (3) and slave (4).
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| CN201420147418.0U CN204065388U (en) | 2014-03-28 | 2014-03-28 | A kind of Secondary Circuit of Potential Transformer pressure drop wireless detection device |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104535952A (en) * | 2015-01-12 | 2015-04-22 | 郑州万特电气股份有限公司 | Electricity use detection tester and allopatric wireless synchronous waveform sampling method thereof |
| CN105158539A (en) * | 2015-07-20 | 2015-12-16 | 钱坤 | Circuit for measuring voltage drop of PT secondary circuit on the basis of voltage drop eliminating device |
| CN105445561A (en) * | 2015-11-10 | 2016-03-30 | 广西电网有限责任公司电力科学研究院 | Wireless measurement instrument for state of electrical equipment in substation |
| CN106093563A (en) * | 2016-05-27 | 2016-11-09 | 东莞市联洲知识产权运营管理有限公司 | A kind of substation secondary side power measuring system and measuring method thereof |
| CN106154026A (en) * | 2016-06-27 | 2016-11-23 | 国网河南省电力公司南阳供电公司 | A kind of Novel secondary pressure drop tester |
| CN107064855A (en) * | 2017-04-12 | 2017-08-18 | 华北电力科学研究院有限责任公司 | Secondary circuit voltage drop monitoring system and method |
| CN107589392A (en) * | 2017-08-10 | 2018-01-16 | 王联喜 | One kind carries out TV secondary voltage drop monitoring devices using concentrator |
| CN110133562A (en) * | 2019-04-03 | 2019-08-16 | 华电电力科学研究院有限公司 | A kind of Secondary Circuit of Potential Transformer pressure drop on-site test system and method |
| CN110196403A (en) * | 2019-06-27 | 2019-09-03 | 西安创奕信息科技有限公司 | A kind of transformer secondary voltage drop on-line monitoring system based on technology of Internet of things |
-
2014
- 2014-03-28 CN CN201420147418.0U patent/CN204065388U/en not_active Expired - Lifetime
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104535952A (en) * | 2015-01-12 | 2015-04-22 | 郑州万特电气股份有限公司 | Electricity use detection tester and allopatric wireless synchronous waveform sampling method thereof |
| CN105158539A (en) * | 2015-07-20 | 2015-12-16 | 钱坤 | Circuit for measuring voltage drop of PT secondary circuit on the basis of voltage drop eliminating device |
| CN105445561A (en) * | 2015-11-10 | 2016-03-30 | 广西电网有限责任公司电力科学研究院 | Wireless measurement instrument for state of electrical equipment in substation |
| CN106093563A (en) * | 2016-05-27 | 2016-11-09 | 东莞市联洲知识产权运营管理有限公司 | A kind of substation secondary side power measuring system and measuring method thereof |
| CN106154026A (en) * | 2016-06-27 | 2016-11-23 | 国网河南省电力公司南阳供电公司 | A kind of Novel secondary pressure drop tester |
| CN106154026B (en) * | 2016-06-27 | 2018-09-18 | 国网河南省电力公司南阳供电公司 | A kind of secondary pressure drop tester |
| CN107064855A (en) * | 2017-04-12 | 2017-08-18 | 华北电力科学研究院有限责任公司 | Secondary circuit voltage drop monitoring system and method |
| CN107589392A (en) * | 2017-08-10 | 2018-01-16 | 王联喜 | One kind carries out TV secondary voltage drop monitoring devices using concentrator |
| CN110133562A (en) * | 2019-04-03 | 2019-08-16 | 华电电力科学研究院有限公司 | A kind of Secondary Circuit of Potential Transformer pressure drop on-site test system and method |
| CN110196403A (en) * | 2019-06-27 | 2019-09-03 | 西安创奕信息科技有限公司 | A kind of transformer secondary voltage drop on-line monitoring system based on technology of Internet of things |
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