CN103792457A - Excitation coil insulation property detection method in electromagnetic flowmeter - Google Patents
Excitation coil insulation property detection method in electromagnetic flowmeter Download PDFInfo
- Publication number
- CN103792457A CN103792457A CN201210508126.0A CN201210508126A CN103792457A CN 103792457 A CN103792457 A CN 103792457A CN 201210508126 A CN201210508126 A CN 201210508126A CN 103792457 A CN103792457 A CN 103792457A
- Authority
- CN
- China
- Prior art keywords
- switching tube
- leakage current
- threshold value
- voltage
- excitation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Measuring Volume Flow (AREA)
Abstract
The invention discloses an excitation coil insulation property detection method in an electromagnetic flowmeter. In order to overcome an influence to flow measurement precision, wherein the influence is generated because an insulation property is reduced and the reduction of the insulation property is generated because an excitation coil is aged or the excitation coil is corroded and so on, the invention provides a method of a leakage current detection circuit. Through controlling conducting states of a switch tube S1, a switch tube S2, a switch tube S3 and a switch tube S4, a leakage current detection signal I is generated. When a leakage current flows through a detection resistor R, two ends of the resistor R generate a voltage V=R*I. An AD converter converts a voltage value into a digital signal and then the digital signal is sent to a microprocessor so as to carry out processing. The microprocessor carries out flow compensation or outputs alarm information according to the detected voltage.
Description
Technical field
the present invention relates to a kind of current flow meter, particularly relate to field coil insulativity detection method in a kind of electromagnetic flowmeter.
Background technology
Field coil in electromagnetic flowmeter is easy to be subject to the corrosion of measured liquid, and the field coil of slight corrosion still can detect flow signal in measuring at the scene, but measuring accuracy cannot guarantee.Field coil after corrosion will form leakage paths between ground at coil, and part exciting current will directly turn back to current source by this leakage paths.This part electric current of revealing will can not produce the required magnetic field of measuring flow signal, and the magnetic field of causing excitation signal to produce is on the low side, and then causes flow measurements on the low side.The long-term use of electromagnetic flowmeter also can cause the aging of field coil, and the insulativity that causes field coil to arrive ground reduces, and this also can cause flow measurements on the low side, affects measuring accuracy.In electromagnetic flowmeter, excitation drive part generally adopts current source, and this cannot detect Leakage Current with regard to the size of current that causes only detection to get back to current source.Current source only can guarantee the current constant through whole energized circuit, cannot detect the size of current of real inflow field coil.
Summary of the invention
the present invention has announced field coil insulativity detection method in a kind of electromagnetic flowmeter, cause insulativity to reduce convection current to measure the impact of accuracy of measurement in order to overcome the reasons such as the aging or field coil corrosion of field coil, the invention provides a kind of method of Leakage Current testing circuit.By the conducting state of gauge tap pipe S1, switching tube S2, switching tube S3, switching tube S4, produce Leakage Current detection signal I, this Leakage Current flows through and detects resistance R and will produce at its two ends voltage V=R*I, and AD converter is converted to this magnitude of voltage to send into microprocessor after digital signal and process; Microprocessor carries out flow-compensated or output alarm information according to the voltage swing detecting.
the object of the present invention is achieved like this:
in the time that the excitation under electromagnetic flowmeter normal operation drives as forward excitation, switching tube S1, switching tube S3 closure, switching tube S2, switching tube S4 disconnect, and direction of current is forward; During for reverse excitation, switching tube S1, switching tube S3 disconnect, switching tube S2, switching tube S4 closure, and direction of current is reverse.
the excitation of electromagnetic flowmeter under detecting pattern drives when normal, wherein switching tube S1 closure, switching tube S2, switching tube S3, switching tube S4 disconnect, if field coil is corroded, will produce leak resistance RL, under the driving of current source, to have Leakage Current I and flow through resistance R L, now can measure the magnitude of voltage detecting between resistance R two ends, this magnitude of voltage is converted to and is sent into microprocessor after digital signal and process by AD converter, if this magnitude of voltage exceedes threshold value 1, judge that field coil produces leakage over the ground; Then judge whether this magnitude of voltage exceedes threshold value 2, if this magnitude of voltage does not exceed threshold value 2, show that field coil Leakage Current is over the ground in the scope that can proofread and correct, adopt correcting algorithm to compensate flow measurements; If exceed threshold value 2, Leakage Current is excessive over the ground to show field coil, cannot proofread and correct by backoff algorithm, now system output alarm information.
system boot does system initialization after starting, system excitation driving condition is set as detecting pattern by configuration switch conduction module, switching tube S1 closure, switching tube S2, switching tube S3, switching tube S4 disconnects, apply exciting current module and produce excitation drive current source, to have Leakage Current and flow through detection resistance R, the magnitude of voltage indirect calculation that detection of leaks electric current I module detects between resistance R by measurement goes out Leakage Current I=V/R, first thresholding comparing unit judges whether Leakage Current I is greater than threshold value 1, if I is less than threshold value 1, show that Leakage Current is very little, system works is normal, if I is greater than threshold value 1, need further to judge whether I is greater than threshold value 2, if I is greater than threshold value 2, show that the Leakage Current of system is excessive, the aging or seriously corroded of field coil, needs more emat coil, and system is by output alarm information, if I is less than threshold value 2, show that system has Leakage Current, can adopt flow-compensated algorithm to compensate flow measurement signal.
beneficial effect of the present invention:
the invention solves the convection current of field coil Leakage Current and measure the impact that accuracy of measurement causes, in the situation that Leakage Current is less, can adopt backoff algorithm microprocessor to compensate flow signal, extend the serviceable life of electromagnetic flowmeter, can estimate the aging or extent of corrosion of field coil, and then estimate serviceable life of magnitude of current flowmeter, provide reference to in-site measurement.
the present invention does not need to add extra complicated circuit, the existing AD converter of microprocessor and a detection resistance are only utilized, can not impact existing measuring system, all compensation and Processing Algorithm all adopt software mode to realize, and are convenient to Site Detection and processing.
accompanying drawing explanation:
1, accompanying drawing 1 is forward excitation driving schematic diagram;
2, accompanying drawing 2 is that reverse excitation drives schematic diagram;
3, accompanying drawing 3 is that under detecting pattern, excitation drives schematic diagram;
4, accompanying drawing 4 is Leakage Current overhaul flow chart.
embodiment:
excitation under electromagnetic flowmeter normal operation drives when the forward excitation as depicted in figs. 1 and 2, switching tube S1(1), switching tube S3(3) closure, switching tube S2(2), switching tube S4(4) disconnect, direction of current is forward; When excitation drives as reverse excitation, switching tube S1(1), switching tube S3(3) disconnect switching tube S2(2), switching tube S4(4) closure, direction of current is reverse.
the excitation of electromagnetic flowmeter under detecting pattern drives when normal as shown in Figure 3, wherein switching tube S1(1) closure, switching tube S2(2), switching tube S3 (3), switching tube S4(4) disconnect, if field coil is corroded, will produce leak resistance RL(9), under the driving of current source (6), to have Leakage Current I and flow through resistance R L(9), now measure the magnitude of voltage detecting between resistance R (5) two ends, this magnitude of voltage is converted to and is sent into microprocessor (8) after digital signal and process by AD converter (7), if show the threshold value 1 that this magnitude of voltage exceedes, judge that field coil produces leakage over the ground, then judge whether this magnitude of voltage exceedes threshold value 2, if this magnitude of voltage does not exceed threshold value 2, show that field coil Leakage Current is over the ground in the scope that can proofread and correct, adopt correcting algorithm to compensate flow measurements, if exceed threshold value 2, Leakage Current is excessive over the ground to show field coil, cannot proofread and correct by backoff algorithm, now system output alarm information.
system boot does system initialization after starting as shown in Figure 4, system excitation driving condition is set as detecting pattern by configuration switch conduction module, configuration switch, apply exciting current module and produce excitation drive current source, to have Leakage Current and flow through detection resistance, the magnitude of voltage indirect calculation that detection of leaks electric current I module detects between resistance by measurement goes out Leakage Current I=V/R, first thresholding comparing unit judges whether Leakage Current I is greater than threshold value 1, if I is less than threshold value 1, show that Leakage Current is very little, system works is normal; If I is greater than threshold value 1, need further to judge whether I is greater than threshold value 2, if I is greater than threshold value 2, show that the Leakage Current of system is excessive, the aging or seriously corroded of field coil, needs more emat coil, and system is by output alarm information; If I is less than threshold value 2, show that system has Leakage Current, can adopt flow-compensated algorithm to compensate flow measurement signal.
Claims (2)
1. field coil insulativity detection method in an electromagnetic flowmeter, it is characterized in that: by gauge tap pipe S1(1), switching tube S2(2), switching tube S3(3), switching tube S4(4) conducting state, produce Leakage Current detection signal I, this Leakage Current flows through and detects resistance R (5) and will produce at its two ends voltage V=R*I, and AD converter (7) is converted to this magnitude of voltage to send into microprocessor (8) after digital signal and process; Microprocessor (8) carries out flow-compensated or output alarm information according to the voltage swing detecting.
2. field coil insulativity detection method in a kind of electromagnetic flowmeter according to claim 1, it is characterized in that: when the excitation under electromagnetic flowmeter normal operation drives as forward excitation, switching tube S1(1), switching tube S3(3) closure, switching tube S2(2), switching tube S4(4) disconnect, direction of current is forward, when excitation drives as reverse excitation, switching tube S1(1), switching tube S3(3) disconnect, switching tube S22, switching tube S4(4) closure, direction of current is reverse, the excitation of electromagnetic flowmeter under detecting pattern drives when normal, wherein switching tube S1(1) closure, switching tube S2(2), switching tube S3 (3), switching tube S4(4) disconnect, if field coil is corroded, will produce leak resistance RL(9), under the driving of current source (6), to have Leakage Current I and flow through resistance R L(9), now measure the magnitude of voltage detecting between resistance R (5) two ends, this magnitude of voltage is converted to and is sent into microprocessor (8) after digital signal and process by AD converter (7), if show the threshold value 1 that this magnitude of voltage exceedes, judge that field coil produces leakage over the ground, then judge whether this magnitude of voltage exceedes threshold value 2, if this magnitude of voltage does not exceed threshold value 2, show that field coil Leakage Current is over the ground in the scope that can proofread and correct, adopt correcting algorithm to compensate flow measurements, if exceed threshold value 2, Leakage Current is excessive over the ground to show field coil, cannot proofread and correct by backoff algorithm, now system output alarm information, system boot does system initialization after starting, system excitation driving condition is set as detecting pattern by configuration switch conduction module, switching tube S1(1) closure, switching tube S2(2), switching tube S3(3), switching tube S4(4) disconnect, apply exciting current module and produce excitation drive current source, to have Leakage Current and flow through detection resistance R (5), the magnitude of voltage indirect calculation that detection of leaks electric current I module detects between resistance R (5) by measurement goes out Leakage Current I=V/R, first thresholding comparing unit judges whether Leakage Current I is greater than threshold value 1, if I is less than threshold value 1, show that Leakage Current is very little, system works is normal, if I is greater than threshold value 1, need further to judge whether I is greater than threshold value 2, if I is greater than threshold value 2, show that the Leakage Current of system is excessive, the aging or seriously corroded of field coil, needs more emat coil, and system is by output alarm information, if I is less than threshold value 2, show that system has Leakage Current, can adopt flow-compensated algorithm to compensate flow measurement signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210508126.0A CN103792457A (en) | 2012-12-03 | 2012-12-03 | Excitation coil insulation property detection method in electromagnetic flowmeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210508126.0A CN103792457A (en) | 2012-12-03 | 2012-12-03 | Excitation coil insulation property detection method in electromagnetic flowmeter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103792457A true CN103792457A (en) | 2014-05-14 |
Family
ID=50668323
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210508126.0A Pending CN103792457A (en) | 2012-12-03 | 2012-12-03 | Excitation coil insulation property detection method in electromagnetic flowmeter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103792457A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104633385A (en) * | 2014-12-07 | 2015-05-20 | 中国石油化工股份有限公司 | Wax-bearing crude conveying pipeline |
| CN110375817A (en) * | 2019-07-24 | 2019-10-25 | 杭州乾博科技有限公司 | A kind of coil induction type water meter of predictable water flow variation |
| CN111742196A (en) * | 2017-12-29 | 2020-10-02 | Abb瑞士股份有限公司 | Clamp on electromagnetic flowmeter |
| CN111964755A (en) * | 2020-07-17 | 2020-11-20 | 北方华锦化学工业股份有限公司 | Electromagnetic flowmeter repairing method |
| CN113624306A (en) * | 2021-09-06 | 2021-11-09 | 宁波水表(集团)股份有限公司 | Fault detection device and method for electromagnetic water meter sensor |
-
2012
- 2012-12-03 CN CN201210508126.0A patent/CN103792457A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104633385A (en) * | 2014-12-07 | 2015-05-20 | 中国石油化工股份有限公司 | Wax-bearing crude conveying pipeline |
| CN104633385B (en) * | 2014-12-07 | 2017-01-25 | 中国石油化工股份有限公司 | Wax-bearing crude conveying pipeline |
| CN111742196A (en) * | 2017-12-29 | 2020-10-02 | Abb瑞士股份有限公司 | Clamp on electromagnetic flowmeter |
| CN110375817A (en) * | 2019-07-24 | 2019-10-25 | 杭州乾博科技有限公司 | A kind of coil induction type water meter of predictable water flow variation |
| CN110375817B (en) * | 2019-07-24 | 2020-08-04 | 杭州乾博科技有限公司 | Coil induction type water meter capable of predicting water flow change |
| CN111964755A (en) * | 2020-07-17 | 2020-11-20 | 北方华锦化学工业股份有限公司 | Electromagnetic flowmeter repairing method |
| CN113624306A (en) * | 2021-09-06 | 2021-11-09 | 宁波水表(集团)股份有限公司 | Fault detection device and method for electromagnetic water meter sensor |
| CN113624306B (en) * | 2021-09-06 | 2023-11-14 | 宁波水表(集团)股份有限公司 | Fault detection device and method for electromagnetic water meter sensor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105891658B (en) | A kind of diagnostic method of open-circuit fault of power tubes of inverter | |
| CN103792457A (en) | Excitation coil insulation property detection method in electromagnetic flowmeter | |
| AU2014244259B2 (en) | Systems and methods for energy harvesting and current and voltage measurements | |
| RU2014103243A (en) | SYSTEM AND METHOD FOR DAMAGE DETECTION AND CABLE POWER SUPPLY SYSTEM FOR DIRECT ELECTRIC HEATING OF UNDERWATER PIPELINES | |
| CN102341680B (en) | Magnetic flowmeter with coil ground path detection | |
| GB2435384A (en) | Method for detecting earth-fault conditions in motor a controller | |
| EP2611013B1 (en) | Apparatus and method for detecting failure of switching device in inverter | |
| CN101268339A (en) | Method for operating an electromagnetic flowmeter and electromagnetic flowmeter | |
| CN203133146U (en) | Transformer neutral point current measuring device | |
| CN102645287B (en) | Motor winding temperature rise detection method | |
| RU2014129555A (en) | METHOD FOR DETERMINING POWER CONSUMPTION, MONITORING SYSTEM AND CONTAINING ITS ELECTRICAL INSTALLATION | |
| CN102607784A (en) | Method for detecting water leakage of tap water pipeline | |
| CN203011496U (en) | Vortex street flow detection experiment device | |
| US9404780B2 (en) | Electromagnetic flow meter, miswiring detection apparatus and miswiring detection method | |
| CN102520347B (en) | Locomotive main circuit-breaker fault detection method and device | |
| KR101027815B1 (en) | Distribution watt-hour meter having leakage-current compensator | |
| CN103389153A (en) | Ultrasonic wave transit time measuring circuit by secondary reflection waves | |
| RU2014130037A (en) | ELECTRICAL CONNECTOR | |
| CN108132375B (en) | Direct current measuring device with feedforward and measuring method | |
| US9551602B2 (en) | Electromagnetic flow meter and magnetic excitation control method | |
| US20130278240A1 (en) | System and method of measuring power produced by a power source | |
| CN103616057A (en) | Method and device for measuring level of water in non-metal container or pipeline | |
| CN204007736U (en) | A kind of electromagnetic flowmeter | |
| JP2017116480A (en) | Watthour meter | |
| EP2477293A3 (en) | Methods and systems involving monitoring circuit connectivity |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20140514 |