CN102680357A - Mechanical pointer SF6 density real-time on-line monitoring device - Google Patents
Mechanical pointer SF6 density real-time on-line monitoring device Download PDFInfo
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Abstract
A mechanical pointer SF6 density real-time on-line monitoring device in the technical field of gas density detection includes a mechanical pointer detecting mechanism, a radial magnetic field arranged at the top of a pointer of the mechanical pointer detecting mechanism and provided with the strength in the range between minus or plus 45mT and minus or plus 75mT and the diameter of 6mm, a non-contact magnetic angle encoding module arranged between a dial and the pointer of the mechanical pointer detecting mechanism and capable of automatically centering, and a digital signal processing unit connected with the non-contact magnetic angle encoding module. The mechanical pointer SF6 density real-time on-line monitoring device adopts the non-contact magnetic angle encoder to directly detect the deflection angle of the pointer so as to achieve the technology of SF6 density on-line signal, and requires not re-mounting the pressure and temperature sensors in the SF6 gas circuit, so as to reduce the risk of gas leakage in SF6.
Description
Technical field
What the present invention relates to is a kind of device of gas density detection range, specifically is a kind of based on Hall magnetic cell and mechanical pointer SF6 density real time and on line monitoring device with teletransmission function.
Background technology
Along with progressively developing into the electric power networks of high capacity, UHV (ultra-high voltage) and transformer station's network of various voltage levels, electric system spreads all over the place; The electric product of sulfur hexafluoride insulation has been widely used in power department; Industrial and mining enterprises have promoted the fast development of power industry.The reliable and secure operation that guarantees the electric product of sulfur hexafluoride insulation has become one of vital task of power department.The arc-extinguishing medium and the insulating medium of the electric product of sulfur hexafluoride insulation are sulfur hexafluoride gas, can not leak gas, if leak gas, just can not guarantee the reliable and secure operation of electric product of sulfur hexafluoride insulation.So the sulfur hexafluoride gas density of the electric product of real time and on line monitoring sulfur hexafluoride insulation is very necessary.
Traditional pointer sulfur hexafluoride density relay is exactly the electric product status detection instrument of detection at any time sulfur hexafluoride insulation; Can on-the-spot display density value when gas leakage or insufficient pressure take place the electric product sulfur hexafluoride gas that detects sulfur hexafluoride insulation, and also have and report to the police and blocking function.Pointer sulfur hexafluoride density relay has reliable characteristics such as directly perceived, but pointer sulfur hexafluoride density relay exist can not real-time Transmission sulfur hexafluoride density signal problem.
Usually the technology that adopts for the teletransmission data problem that solves real-time monitoring is that the measuring unit (pointer density monitor part and electron pressure and temperature sensor section) that two covers are separate embeds same SF6 gas circuit.But such technology existence is overlapped separate because of two and the measuring principle different sensor embeds the risk that same SF6 gas circuit is prone to cause the leakage of SF6 gas; And very easily cause measurement result inconsistent (remote transfer signal value and on-the-spot displayed value inconsistent) thereby the fault that causes supervisory system to judge by accident because of the different separate sensor of two covers of measuring principle.
Chinese patent document number CN202084170U, open day 2011-12-21 discloses a kind of " contactless SF6 density monitor signal transmission module "; Relate to a kind of gas density relay pick-up unit; Comprise at least one control terminal, density monitor check meter, wireless transmission unit, signal receiving module, control terminal include switching value detecting unit, microprocessor, radio-frequency module; The switching value detecting unit is gathered switch state signal, and radio-frequency module is used for the transmitting switch status signal; Signal receiving module receiving key status signal, this technology adopt the Hall DC current sensor accurately to judge the relay switch state; Realize distance relay state transfer and remote contacts status output through radio-frequency technique.But this technology can only non-contact detection switching value signal, can not detect continuous SF6 density simulating signal.
Chinese patent document number CN101750102, open day 2010-06-23 has put down in writing a kind of " the rotation angle measurement method of magnetic-electric rotary encoder and magneto-electric ", and this device comprises magneto-electric induction unit, rotary magnet and external microprocessor.The magneto-electric induction unit is arranged on the controlling object, is used for producing a voltage according to the lip-deep changes of magnetic field of controlling object, and calculates the encoded radio of expression controlling object angle information according to voltmeter.Be installed in the top of magneto-electric induction unit, and the shaft core position of rotary magnet immobilizes the rotary magnet non-contact type.External microprocessor links to each other with the magneto-electric induction unit, is used to read the encoded radio that the magneto-electric induction unit calculates, and the output control signal.But should technology directly measure the weak voltage that the magneto-electric induction unit produces according to changes of magnetic field, and calculate the encoded radio of representing the controlling object angle information, and receive the outer signals interference easily and cause the testing result error bigger according to voltmeter.
In sum, present stage is badly in need of solving pick-up unit because its test philosophy is different, makes SF6 density remote transfer signal value and on-the-spot displayed value that inconsistent problem take place often.
Summary of the invention
The objective of the invention is to solve the deficiency of above-mentioned prior art; A kind of mechanical pointer SF6 density real time and on line monitoring device is provided; Adopt contactless magnetic degree scrambler directly to detect the technology that the needle deflection angle obtains SF6 density live signal; Need not in the SF6 gas circuit setting pressure and temperature sensor again, can reduce the risk that gas leakage takes place SF6.It is inconsistent that the present invention can solve the measurement result that causes because of the different separate sensor of two covers of employing measuring principle; The inconsistent problem that causes SF6 density remote transfer signal value and on-the-spot displayed value, and pointer sulfur hexafluoride density relay can not be monitored problem in real time because of the function of no long-distance transmissions SF6 density signal.
The present invention realizes through following technical scheme; The present invention includes: mechanical indicator testing agency, be arranged at mechanical indicator testing agency the pointer top intensity ± 45mT to ± 75mT scope interior diameter be between the radial magnetic field of 6mm, the index dial that is arranged at mechanical indicator testing agency and the pointer and contactless magnetic degree coding module that can automatic centering, the digital signal processing unit that links to each other with contactless magnetic degree coding module; Wherein: contactless magnetic degree coding module is the rotation radial magnetic field variable quantity at center with the axle core through the pointer that detects mechanical indicator testing agency; And the output transducer coordinates matrix is to digital signal processing unit, digital signal processing unit to absolute value angular coding value carry out the digital averaging value handle with eliminate external signal disturb to the influence of measuring and after digital signal processing unit digital-to-analog conversion and processing and amplifying the analog signal form with 4-20mA export.
Described contactless magnetic degree coding module comprises: the sensor array and front end analogue amplifier, ∑-Δ analog to digital converter and the output interface unit that adopt the X-Y packet configuration; Wherein: the Y group pattern of sensor array and X group pattern respectively with the counterparty to the front end analogue amplifier link to each other and export the first differential signal Y1-Y2 and the second differential signal X1-X2; The front end analogue amplifier links to each other with ∑-Δ analog to digital converter; After analog to digital conversion, export differential signal to the output interface unit, export the sensor coordinates matrix to digital signal processing unit through the output interface unit.
Described digital signal processing unit reads from the absolute value angle of magnetic degree scrambler output and calculates to solve the nonlinear relationship of SF6 density signal and deflection angle through trigonometric function; To guarantee that SF6 density remote transfer signal value and on-the-spot displayed value are consistent; This digital signal processing unit comprises: trigonometric function computing unit, digital filtering module, coding unit, storer and D/A converter module that links to each other with coding unit successively and amplification module; Wherein: the trigonometric function computing unit receive the output of contactless magnetic degree coding module the sensor coordinates matrix and according to two groups of differential digital signal obtain sinusoidal vector sum cosine vector with and the arctan function of both ratios; Angle preset value to the trigonometric function computing unit that storer output prestores is exported the angle absolute value to digital filtering module after superposeing; Digital filtering module adopts the moving average filter method to carry out filtering and export coding unit to reading the tested angle absolute value that obtains the output of trigonometric function computing unit; Coding unit exports D/A converter module and amplification module to after encoding according to the angle absolute value successively, and the analog signal form with 4-20mA after digital-to-analog conversion and processing and amplifying is exported.
Described contactless magnetic degree coding module and digital signal processing unit are integrated on the fan-shaped circuit board with automatic centering structure; Wherein contactless magnetic degree coding module is positioned at the ligulate zone that fan-shaped circuit board adopts the isoceles triangle principle design; Have centering fixed function with pointer sulfur hexafluoride density relay mechanical detection mechanism, correct with radial magnetic field and the contactless magnetic degree scrambler relative position guaranteeing to rotate.
Described pointer, contactless magnetic degree coding module and fan-shaped circuit board from top to bottom are arranged at the below of the meter dial of density monitor successively.
The present invention utilizes the variation of rotation radial magnetic field; Contactless direct detection pointer magnetic deflection angle; Obtain the SF6 density signal after digital signal processing unit is handled, export with analog quantity current signal (4-20mA) and with the RS485 serial communication digital signal of MODBUS agreement respectively; Combined electrical apparatus, isolating switch, on-pole switch, transformer and the mutual inductor that can be widely used in the sulfur hexafluoride insulation.
Description of drawings
Fig. 1 is a synoptic diagram of the present invention.
Fig. 2 is a perspective view of the present invention.
Fig. 3 is a mechanical indicator testing agency synoptic diagram.
Fig. 4 is the signal processing module front elevation.
Fig. 5 is the Hall sensor array synoptic diagram.
Embodiment
Elaborate in the face of embodiments of the invention down, present embodiment provided detailed embodiment and concrete operating process, but protection scope of the present invention is not limited to following embodiment being to implement under the prerequisite with technical scheme of the present invention.
Embodiment
Like Fig. 1-shown in Figure 3; Present embodiment comprises: mechanical indicator testing agency 1, be arranged at mechanical indicator testing agency 1 pointer 4 tops intensity ± 45mT to ± 75mT scope interior diameter be between the radial magnetic field 2 of 6mm, the index dial 3 that is arranged at mechanical indicator testing agency 1 and the pointer 4 and contactless magnetic degree coding module 5 that can automatic centering, the digital signal processing unit 6 that links to each other with contactless magnetic degree coding module 5; Wherein: contactless magnetic degree coding module 5 is rotation radial magnetic field 2 variable quantities at center with the axle core through the pointer 4 that detects mechanical indicator testing agency 1; And the absolute value angular coding value of exporting this variable quantity is to digital signal processing unit 6,6 pairs of absolute value angular codings of digital signal processing unit value carry out the digital averaging value handle with eliminate external signal disturb to the influence of measuring and successively after digital-to-analog conversion and processing and amplifying the analog signal form with 4-20mA export.
Described contactless magnetic degree coding module 5 comprises: the sensor array 9 and front end analogue amplifier 10, ∑-Δ analog to digital converter 11 and the output interface unit 12 that adopt the X-Y packet configuration; Wherein: the Y group pattern of sensor array 9 and X group pattern respectively with the counterparty to front end analogue amplifier 10 link to each other and export the first differential signal Y1-Y2 and the second differential signal X1-X2; Front end analogue amplifier 10 links to each other with ∑-Δ analog to digital converter 11; After analog to digital conversion, export differential signal to output interface unit 12, export the sensor coordinates matrix to digital signal processing unit 6 through output interface unit 12.
As shown in Figure 5; What described sensor array 9 adopted is that radius is the annular Hall sensor array 18 of 1.1mm; Hall magnetic cell in this array 18 is arranged with the two-dimensional quadrature mode, and the center of circle O of annular Hall sensor array 18 is over against the needle pivot 17 of mechanical indicator testing agency.
Described digital signal processing unit 6 reads from the absolute value angle of magnetic degree scrambler output and calculates to solve the nonlinear relationship of SF6 density signal and deflection angle through trigonometric function; To guarantee that SF6 density remote transfer signal value and on-the-spot displayed value are consistent; This digital signal processing unit 6 comprises: trigonometric function computing unit 13, digital filtering module 14, coding unit 15, storer 16 and D/A converter module 7 that links to each other with coding unit 15 successively and amplification module 8; Wherein: trigonometric function computing unit 13 receive contactless magnetic degree coding module 5 outputs the sensor coordinates matrix and according to two groups of differential digital signal obtain sinusoidal vector sum cosine vector with and the arctan function of both ratios; Angle preset value to the trigonometric function computing unit 13 that storer 16 outputs prestore is exported the angle absolute value to digital filtering module 14 after stack; Digital filtering module 14 adopts moving average filter method angle absolute value to carry out filtering and export coding unit 15 to; Export D/A converter module 7 and amplification module 8 after coding unit 15 is encoded according to the angle absolute value successively to, the analog signal form with 4-20mA after digital-to-analog conversion and processing and amplifying is exported.
Described moving average filter method is meant: the moving average filter method is regarded some measurement data as a formation, and the length of formation is fixing natural constant N, whenever carries out once new sampling, puts into tail of the queue to measurement result, and removes data of original head of the queue; N measurement data arrangement through calculate the output angle absolute value that the back obtains through trigonometric function computing unit 13 is set to the formation that length is fixed as N, and carries out following processing with the formation mode:
Wherein:
Be that the n time sampling is through filtered output, X
N-iBe the n-i time sampled value of non-filtered, n is 1 to N natural constant, and N is running mean item number, i.e. queue length.
Described running mean item number N is preferably 7-15.
As shown in Figure 4, described contactless magnetic degree coding module 5 and digital signal processing unit 6 are integrated on the fan-shaped circuit board 0 with automatic centering structure, and wherein contactless magnetic degree coding module 5 is positioned at the ligulate zone, center 19 of fan-shaped circuit board 0.
As shown in Figure 3, described mechanical indicator testing agency 1 comprises: the needle pivot 17 that sets gradually, pointer 4 and magnet steel 18, and wherein: magnet steel 18 is arranged at the end of pointer 4, and the slewing area of pointer 4 is over against contactless magnetic degree coding module 5.
The magnetic field of described magnet steel 18 is for radially being provided with.
Described pointer 4, contactless magnetic degree coding module 5 and fan-shaped circuit board 0 from top to bottom are arranged at the below of the meter dial 3 of density monitor successively.
The action principle of present embodiment is based on the flexible member Bourdon tube and utilizes the temperature compensation sheet that change pressure and temperature are revised, the variation of the sulfur hexafluoride gas density in the reaction closed container.Promptly under the pressure effect of measured medium sulfur hexafluoride gas; Because the effect of temperature compensation sheet has been arranged; The variation of its density value, force value also change the end that forces Bourdon tube accordingly and produce corresponding elastic deformation-displacement, pass to movement by means of temperature compensation sheet and connecting link; Movement passes to pointer 4 again, will be recorded the sulfur hexafluoride gas density value and on index dial 3, indicate.This measuring principle is widely used.Present embodiment utilizes contactless magnetic degree scrambler 4 directly to detect pointer 4 deflection angles and obtains the sulfur hexafluoride density signal.Contactless magnetic degree coding module 5 is set with the digital signal processing of magnetic degree scrambler 4 and convert the 4-20mA remote transmission signal in the watchcase.
Claims (7)
1. mechanical pointer SF6 density real time and on line monitoring device; It is characterized in that; Comprise: mechanical indicator testing agency, be arranged at mechanical indicator testing agency the pointer top intensity ± 45mT to ± 75mT scope interior diameter be between the radial magnetic field of 6mm, the index dial that is arranged at mechanical indicator testing agency and the pointer and contactless magnetic degree coding module that can automatic centering, the digital signal processing unit that links to each other with contactless magnetic degree coding module; Wherein: contactless magnetic degree coding module is the rotation radial magnetic field variable quantity at center with the axle core through the pointer that detects mechanical indicator testing agency; And the output transducer coordinates matrix is to digital signal processing unit, digital signal processing unit to absolute value angular coding value carry out the digital averaging value handle with eliminate external signal disturb to the influence of measuring and after digital signal processing unit digital-to-analog conversion and processing and amplifying the analog signal form with 4-20mA export;
Described contactless magnetic degree coding module comprises: the sensor array and front end analogue amplifier, ∑-Δ analog to digital converter and the output interface unit that adopt the X-Y packet configuration; Wherein: the Y group pattern of sensor array and X group pattern respectively with the counterparty to the front end analogue amplifier link to each other and export the first differential signal Y1-Y2 and the second differential signal X1-X2; The front end analogue amplifier links to each other with ∑-Δ analog to digital converter; After analog to digital conversion, export differential signal to the output interface unit, export the sensor coordinates matrix to digital signal processing unit through the output interface unit;
What described sensor array adopted is that radius is the annular Hall sensor array of 1.1mm, and the Hall magnetic cell in this array is arranged with the two-dimensional quadrature mode, and the center of circle of annular Hall sensor array is over against mechanical indicator testing agency;
Described digital signal processing unit reads from the absolute value angle of magnetic degree scrambler output and calculates to solve the nonlinear relationship of SF6 density signal and deflection angle through trigonometric function; To guarantee that SF6 density remote transfer signal value and on-the-spot displayed value are consistent; This digital signal processing unit comprises: trigonometric function computing unit, digital filtering module, coding unit, storer and D/A converter module that links to each other with coding unit successively and amplification module; Wherein: the trigonometric function computing unit receive the output of contactless magnetic degree coding module the sensor coordinates matrix and according to two groups of differential digital signal obtain sinusoidal vector sum cosine vector with and the arctan function of both ratios; Angle preset value to the trigonometric function computing unit that storer output prestores is exported the angle absolute value to digital filtering module after superposeing; Digital filtering module adopts the moving average filter method to carry out filtering and export coding unit to reading the tested angle absolute value that obtains the output of trigonometric function computing unit; Coding unit exports D/A converter module and amplification module to after encoding according to the angle absolute value successively, and the analog signal form with 4-20mA after digital-to-analog conversion and processing and amplifying is exported;
Described contactless magnetic degree coding module and digital signal processing unit are integrated on the fan-shaped circuit board with automatic centering structure; Wherein contactless magnetic degree coding module is positioned at the ligulate zone that fan-shaped circuit board adopts the isoceles triangle principle design; Have centering fixed function with pointer sulfur hexafluoride density relay mechanical detection mechanism, correct with radial magnetic field and the contactless magnetic degree scrambler relative position guaranteeing to rotate.
2. the direct measuring system of mechanical type pointer instrument deflection angle according to claim 1; It is characterized in that; Described moving average filter method is meant: the moving average filter method is regarded some measurement data as a formation, and the length of formation is fixing natural constant N, whenever carries out once new sampling; Put into tail of the queue to measurement result, and remove data of original head of the queue; N measurement data arrangement through calculate the output angle absolute value that the back obtains through the trigonometric function computing unit is set to the formation that length is fixed as N, and carries out following processing with the formation mode:
Wherein:
Be that the n time sampling is through filtered output, X
N-iBe the n-i time sampled value of non-filtered, n is 1 to N natural constant, and N is running mean item number, i.e. queue length.
3. the direct measuring system of mechanical type pointer instrument deflection angle according to claim 2 is characterized in that, described running mean item number N is 7-15.
4. the direct measuring system of mechanical type pointer instrument deflection angle according to claim 1; It is characterized in that; Described contactless magnetic degree coding module and digital signal processing unit are integrated on the fan-shaped circuit board with automatic centering structure, and wherein contactless magnetic degree coding module is positioned at the ligulate zone, center of fan-shaped circuit board.
5. the direct measuring system of mechanical type pointer instrument deflection angle according to claim 1; It is characterized in that; Described mechanical indicator testing agency comprises: the needle pivot that sets gradually, pointer and magnet steel; Wherein: magnet steel is arranged at the end of pointer, and the slewing area of pointer is over against contactless magnetic degree coding module.
6. the direct measuring system of mechanical type pointer instrument deflection angle according to claim 5 is characterized in that, the magnetic field of described magnet steel is for radially being provided with.
7. the direct measuring system of mechanical type pointer instrument deflection angle according to claim 5; It is characterized in that described pointer, contactless magnetic degree coding module and fan-shaped circuit board from top to bottom are arranged at the below of the meter dial of density monitor successively.
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| CN2012101801968A CN102680357A (en) | 2012-06-01 | 2012-06-01 | Mechanical pointer SF6 density real-time on-line monitoring device |
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| CN2012101801968A CN102680357A (en) | 2012-06-01 | 2012-06-01 | Mechanical pointer SF6 density real-time on-line monitoring device |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106596326A (en) * | 2016-12-02 | 2017-04-26 | 河南省日立信股份有限公司 | Sulfur hexafluoride and nitrogen mixed gas density variation monitoring system and monitoring method |
| CN106872564A (en) * | 2015-12-14 | 2017-06-20 | 国网智能电网研究院 | A kind of SF6Gas sensor |
| CN107356934A (en) * | 2017-08-04 | 2017-11-17 | 合肥工业大学 | Sulfur hexafluoride leakage detection method and device based on DIAL |
| CN110285917A (en) * | 2019-06-21 | 2019-09-27 | 国家电网有限公司 | The method and SF6 meter of SF6 meter measuring and calculating pressure value |
| CN110364390A (en) * | 2019-07-16 | 2019-10-22 | 上海上芃电气有限公司 | A kind of SF6 gas teletransmission density monitor with self-test |
| CN110376286A (en) * | 2019-06-13 | 2019-10-25 | 国网浙江省电力有限公司电力科学研究院 | A kind of in-service disc insulator intelligent automation ultrasonic testing system and method |
| CN110595941A (en) * | 2019-09-04 | 2019-12-20 | 上海乐研电气有限公司 | Medium-high voltage electrical equipment gas leakage monitor and monitoring system |
| CN110987204A (en) * | 2019-12-04 | 2020-04-10 | 南京韦伯测控技术有限公司 | Intelligent transmitting device for measuring temperature of large oil-immersed power transformer winding |
| CN111146986A (en) * | 2019-12-30 | 2020-05-12 | 深圳市越疆科技有限公司 | Position locating method and device of magnetic encoder, electronic equipment and computer readable storage medium |
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- 2012-06-01 CN CN2012101801968A patent/CN102680357A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106872564A (en) * | 2015-12-14 | 2017-06-20 | 国网智能电网研究院 | A kind of SF6Gas sensor |
| CN106872564B (en) * | 2015-12-14 | 2020-09-25 | 国网智能电网研究院 | SF (sulfur hexafluoride)6Gas sensor |
| CN106596326A (en) * | 2016-12-02 | 2017-04-26 | 河南省日立信股份有限公司 | Sulfur hexafluoride and nitrogen mixed gas density variation monitoring system and monitoring method |
| CN107356934A (en) * | 2017-08-04 | 2017-11-17 | 合肥工业大学 | Sulfur hexafluoride leakage detection method and device based on DIAL |
| CN110376286A (en) * | 2019-06-13 | 2019-10-25 | 国网浙江省电力有限公司电力科学研究院 | A kind of in-service disc insulator intelligent automation ultrasonic testing system and method |
| CN110285917A (en) * | 2019-06-21 | 2019-09-27 | 国家电网有限公司 | The method and SF6 meter of SF6 meter measuring and calculating pressure value |
| CN110285917B (en) * | 2019-06-21 | 2021-10-22 | 国家电网有限公司 | Method for measuring and calculating pressure value by using SF6 meter and SF6 meter |
| CN110364390A (en) * | 2019-07-16 | 2019-10-22 | 上海上芃电气有限公司 | A kind of SF6 gas teletransmission density monitor with self-test |
| CN110595941A (en) * | 2019-09-04 | 2019-12-20 | 上海乐研电气有限公司 | Medium-high voltage electrical equipment gas leakage monitor and monitoring system |
| CN110987204A (en) * | 2019-12-04 | 2020-04-10 | 南京韦伯测控技术有限公司 | Intelligent transmitting device for measuring temperature of large oil-immersed power transformer winding |
| CN111146986A (en) * | 2019-12-30 | 2020-05-12 | 深圳市越疆科技有限公司 | Position locating method and device of magnetic encoder, electronic equipment and computer readable storage medium |
| CN111146986B (en) * | 2019-12-30 | 2022-08-12 | 深圳市越疆科技有限公司 | Position locating method and device of magnetic encoder, electronic equipment and computer readable storage medium |
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Application publication date: 20120919 |