CN108205073B - Induction display type electronic voltage mutual induction system and voltage detection method thereof - Google Patents
Induction display type electronic voltage mutual induction system and voltage detection method thereof Download PDFInfo
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- CN108205073B CN108205073B CN201810014316.4A CN201810014316A CN108205073B CN 108205073 B CN108205073 B CN 108205073B CN 201810014316 A CN201810014316 A CN 201810014316A CN 108205073 B CN108205073 B CN 108205073B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R13/00—Arrangements for displaying electric variables or waveforms
- G01R13/02—Arrangements for displaying electric variables or waveforms for displaying measured electric variables in digital form
- G01R13/0209—Arrangements for displaying electric variables or waveforms for displaying measured electric variables in digital form in numerical form
Abstract
The invention discloses an induction display type electronic voltage mutual induction system, which comprises a display and more than one electronic voltage transformer; the electronic voltage transformer comprises a cylindrical insulating casting, wherein one end face of the insulating casting is provided with a first interface, the other end face of the insulating casting is provided with a second interface, a first spherical electrode is arranged in the insulating casting close to the first interface end and is electrically connected with one end of the first interface, and the other end of the first interface is electrically connected with a high-voltage bus in high-voltage equipment; a second spherical electrode and a signal processor are respectively arranged in the insulating casting close to the second interface end; one end of the signal processor is electrically connected with the second spherical electrode, and the other end of the signal processor is electrically connected with the display. The invention can detect the voltage of the high-voltage charged body by using the two spherical electrodes, cancels the transmission link of the analog signal, thoroughly eliminates the influence of various uncontrollable interference factors in the transmission process of the analog signal and greatly improves the stability and the measurement precision of the system.
Description
Technical Field
The invention relates to the field of sensors, in particular to an induction display type electronic voltage mutual induction system.
Background
⑴ is large in size, heavy in weight, inconvenient to install and use, complex in insulation structure, easy to generate process defects and potential safety hazards in order to meet high-voltage insulation requirements, ⑵ is easy to cause explosion accidents of the mutual inductor due to iron core resonance of an electromagnetic coil, ⑶ is easy to generate measurement errors and even cause protection misoperation due to the influence of nonlinearity of ferromagnetic materials, magnetic saturation benefits, magnetic leakage and the like, ⑷ is easy to interfere in long-distance transmission of analog signals obtained by detection, and a measurement system is composed of multiple stages to cause reduction of measurement accuracy.
Because of the disadvantages of the conventional high voltage detection, along with the development of scientific technology, various non-conventional and electronic voltage measurement methods have entered the research and development stage for over ten years, and the conventional electronic sensing devices can be divided into two types, i.e., voltage division type and optical type. The voltage division measurement is generally two types of capacitance voltage division and resistance voltage division, and a voltage division device has potential safety hazard due to direct contact with a high-voltage charged body. The capacitive measurement system also has the phenomenon of doubling the detection voltage, and is also an interference to the protection system. In addition, the voltage dividing element is easily interfered by elements aging, temperature and other external factors, and has poor stability and interchangeability, and the commercialization is difficult to realize. The optical structure has the problems of poor stability, poor interchangeability and the like due to the complex structure, and is higher in price. Practice proves that the electronic mutual inductor has fatal defects, so that the electronic mutual inductor is difficult to be put into practical use.
The non-contact sensor (i.e. inductive sensor) is installed in high-voltage equipment as a support of a charged body (high-voltage bus bar) by adopting the principle of sensing high-voltage electric field signals, receives the electric field signals of the charged body, and then sends the received voltage signals to a controller. Although the method is safer than the former two methods, the method is easily influenced by factors such as air humidity, installation distance between the sensor and the charged body and the like, and the detected voltage error is larger.
Disclosure of Invention
Therefore, it is necessary to provide an induction display type electronic voltage transformer system which is not affected by humidity, does not need to use an iron core coil, has high detection accuracy, and has good stability, and a method for detecting voltage.
In order to achieve the above object, the inventor provides an induction display type electronic voltage transformer system, which includes a display and more than one electronic voltage transformer, wherein the display is electrically connected with each electronic voltage transformer; the electronic voltage transformer comprises a cylindrical insulating casting, wherein one end face of the insulating casting is provided with a first interface, the other end face of the insulating casting is provided with a second interface, a first spherical electrode is arranged in the insulating casting close to the first interface end and is electrically connected with one end of the first interface, and the other end of the first interface is electrically connected with a high-voltage bus in high-voltage equipment; a second spherical electrode and a signal processor are respectively arranged in the insulating casting close to the second interface end; one end of the signal processor is electrically connected with the second spherical electrode, and the other end of the signal processor is electrically connected with the display.
Further, the radius of the first spherical electrode is 1-10mm, and the radius of the second spherical electrode is 20-30 mm.
Furthermore, a voltage detection unit is arranged in the signal processor, and the voltage detection unit is a resistor.
Further, the minimum distance between the first and second ball electrodes is greater than 10mm, thereby avoiding voltage breakdown of the first and second ball electrodes.
Further, the second interface is grounded, and the signal processor is grounded.
Further, the number of the electronic voltage transformers is 1 or 3.
Furthermore, the insulation casting is an epoxy resin casting, a bakelite casting or a high-voltage silica gel casting.
The invention also provides a method for detecting voltage by the induction display type electronic voltage mutual induction system, which comprises the following steps:
1) the other end of the first interface of the electronic voltage transformer is electrically connected with a high-voltage bus in high-voltage equipment, and the electronic voltage transformer is arranged in the high-voltage equipment through the second interface to be used as a support of the high-voltage bus;
2) when the high-voltage equipment is in a power-on state, the high-voltage bus forms a high-voltage electric field; the first spherical electrode and the second spherical electrode are both spherical and are electrically connected with the high-voltage bus bar, so that an uneven electric field is formed by the first spherical electrode and the second spherical electrode; in the formed uneven electric field, the surface of the first spherical electrode has stronger electric field intensity because the curvature radius of the first spherical electrode is smaller than that of the second spherical electrode; under the action of the strong electric field intensity, an ionized layer is generated in a micron-sized area away from the surface of the first spherical electrode, so that a migration current is formed between the first spherical electrode and the second spherical electrode;
3) the signal processor detects the voltage corresponding to the migration current on the second spherical electrode, the voltage corresponding to the migration current is positively correlated with the electrified voltage of the high-voltage busbar, so that the detected voltage value is converted into an electrified voltage signal of the high-voltage busbar, and the signal processor sends the processed voltage signal to the display.
Further, the voltage signal processed by the signal processor comprises a voltage effective value signal and a voltage analog signal.
Further, a resistor is arranged in the signal processor, the resistor is electrically connected with the second spherical electrode, and the voltage value of the migration current is measured through the resistor.
The invention has the beneficial effects that:
(1) and a non-contact voltage measuring mode is adopted, so that hidden dangers such as iron core resonance, insulation breakdown and the like are avoided, and the safety is absolutely guaranteed.
(2) Compared with the existing equipment, the invention adopts an integrated detection structure, the electronic voltage transformer can directly obtain a detection voltage value, the display directly displays the live voltage of the high-voltage equipment after conversion, the detection equipment is simple, the transmission of a plurality of equipment is not needed, the detection precision is high, and the stability is good.
(3) The electronic voltage transformer has the advantages of small structure, simplified secondary wiring and convenience in installation and maintenance.
(4) The detected voltage signal is transmitted to the display in a digital mode, and the anti-interference capacity is high.
(5) The PT cabinet can be cancelled, the electric land is saved, and the user investment is saved.
Drawings
Fig. 1 is a schematic structural diagram of an induction display type electronic voltage transformer system according to embodiment 1.
Description of reference numerals:
1. a display; 2. an electronic voltage transformer; 21, insulating casting; 22. a first interface; 23. a second interface; 24. a first spherical electrode; 25. a second spherical electrode; 26 a signal processor; 27. a resistance; 3. the high-voltage busbar is arranged.
Detailed Description
To explain technical contents, structural features, and objects and effects of the technical solutions in detail, the following detailed description is given with reference to the accompanying drawings in conjunction with the embodiments.
Referring to fig. 1, the induction display type electronic voltage transformer system of the present embodiment includes a display 1 and at least one electronic voltage transformer 2, wherein the display 1 is electrically connected to each electronic voltage transformer 2; the electronic voltage transformer 2 comprises a cylindrical insulating casting 21, one end face of the insulating casting 21 is provided with a first interface 22, the other end face of the insulating casting 21 is provided with a second interface 23, a first spherical electrode 24 is arranged in the insulating casting 21 and close to the first interface end, the first spherical electrode 24 is electrically connected with one end of the first interface 22, and the other end of the first interface 22 is electrically connected with a high-voltage bus 3 in high-voltage equipment; a second spherical electrode 25 and a signal processor 26 are respectively arranged in the insulating casting 21 and close to the second interface end; one end of the signal processor 26 is electrically connected to the second spherical electrode 25, and the other end of the signal processor is electrically connected to the display 1.
In a preferred embodiment, the insulation casting 21 is an epoxy casting, bakelite casting, or high-voltage silicone casting. In other embodiments, other conventional insulating materials may also be used to form the insulating casting. In addition, the shape of the insulation casting 21 is not limited to the cylindrical shape, and may be other conventional shapes such as a cube and the like.
The invention further discloses a method for detecting voltage by using the induction display type electronic voltage mutual induction system in the embodiment 1, which comprises the following steps:
1) the other end of a first interface 22 of the electronic voltage transformer is electrically connected with a high-voltage bus bar 3 in high-voltage equipment, and the electronic voltage transformer is arranged in the high-voltage equipment through a second interface 23 to be used as a support of the high-voltage bus bar; the number of the electronic voltage transformers 2 can be one or three, and the electronic voltage transformers can be used for measuring single-phase voltage or three-phase voltage. When three electronic voltage transformers are arranged to measure three-phase voltages, each electronic voltage transformer correspondingly measures one phase voltage, and each electronic voltage transformer 2 is electrically connected with a high-voltage bus bar 3 of the corresponding phase voltage in the high-voltage equipment.
2) When the high-voltage equipment is in a power-on state, the high-voltage bus 3 forms a high-voltage electric field; because the first spherical electrode 24 and the second spherical electrode 25 are both spherical and the first spherical electrode 24 is electrically connected with the high-voltage bus bar 3, the first spherical electrode 24 and the second spherical electrode 25 form an uneven electric field; in the formed uneven electric field, the first spherical electrode 24 has stronger electric field intensity on the surface because the radius of the first spherical electrode 24 is smaller than that of the second spherical electrode 25; under the action of the strong electric field intensity, an ionized layer is generated in a micron-sized area away from the surface of the first spherical electrode (generally, the ionized layer is generated in an area of tens of microns), so that a migration current is formed between the first spherical electrode 24 and the second spherical electrode 25;
3) the signal processor 26 detects the voltage corresponding to the migration current on the second spherical electrode 25, and since the voltage corresponding to the migration current and the charged voltage of the high-voltage bus bar 3 have a relatively stable positive correlation, the detected voltage value is converted into a charged voltage signal of the high-voltage bus bar, and the signal processor 26 sends the processed voltage signal to the display 1 for display. The voltage signal processed by the signal processor 26 includes a voltage effective value signal and a voltage analog signal. The value of the effective value of the voltage can be displayed on the display 1 according to the user's requirements. In the occasions of needing to detect faults of high-voltage equipment and the like, voltage analog signals can be sent to a display, and the display can display a voltage oscillogram, so that a user can carry out phase analysis, and the fault reason and the like can be conveniently found out.
In a preferred embodiment, a resistor 27 is disposed in the signal processor 26, the resistor 27 is electrically connected to the second spherical electrode 25, and the voltage value of the migration current is measured through the resistor. When the migration current flows through the resistor, the passing voltage value can be calculated through the resistance value of the resistor, and therefore the voltage value corresponding to the migration current is obtained.
In a specific application, the electronic voltage transformer 2 may be calibrated in advance. The electronic voltage transformer 2 is firstly installed in high-voltage equipment with a known voltage value, and then the conversion relation between the detected voltage value and the actual voltage value is obtained according to the voltage value detected by the signal processor. Continuously detecting for 5-10 times, and continuously correcting the conversion value. And (4) correcting the voltage value again by using other high-voltage equipment with known voltage values, and correcting the electronic voltage transformer by using more than 3 high-voltage equipment with known voltage values to obtain the conversion relation between the final detected voltage value and the actual voltage value.
According to the principle of the electric field effect, the voltage carried by the high-voltage charged body can be detected by the two spherical electrodes, various interference factors inherent to the traditional mutual inductor are completely eliminated, and a real and reliable information source is provided for subsequent voltage measurement, fault waveform analysis, phase information, electric energy calculation, protection analysis and the like.
In this embodiment, the signal processor 26 and the two detection electrodes are both built in the same insulation casting 21, and since the epoxy resin has good high-voltage insulation performance, the insulation strength between the non-contact electrodes is ensured, and the safety is ensured. And secondly, the signal processor can directly obtain a detection voltage value, a transmission link of an analog signal is cancelled, the influence of various uncontrollable interference factors in the transmission process of the analog signal is thoroughly eliminated, and the system stability and the measurement precision are greatly improved.
In a preferred embodiment, the radius of the first spherical electrode 24 is 1-10mm, and the radius of the second spherical electrode 25 is 20-30 mm. Since the radius of the first spherical electrode 24 is smaller than the radius of the second spherical electrode 25, a strong electric field intensity is likely to be generated on the surface of the first spherical electrode 24 in the uneven electric field formed by the first spherical electrode 24 and the second spherical electrode 25.
In a preferred embodiment, the minimum distance between the first ball electrode 24 and the second ball electrode 25 is greater than 10 mm. In order to avoid the breakdown of the two ball electrodes by voltage, a certain safety distance is required between the two ball electrodes. Therefore, the minimum safe distance between the two spherical electrodes needs to be more than 10 mm.
Further, the second interface 23 is grounded, and the signal processor 26 is grounded, so that the two spherical electrodes and the second interface or the signal processor form a complete loop.
Further, the number of the electronic voltage transformers 2 is 1 or 3. According to specific detection requirements, when detecting single-phase voltage, then adopt an electronic voltage transformer 2, when needs detect three-phase voltage, then adopt 3 electronic voltage transformer. In fact, the number of the electronic voltage transformers 2 can be set at will according to requirements, and then all the electronic voltage transformers share one display, and the display can display multiple groups of voltage values.
Furthermore, the high-voltage equipment is a high-voltage switch cabinet or a high-voltage metering cabinet.
The detection system and the detection method have the following advantages that:
(1) and a non-contact voltage measuring mode is adopted, so that hidden dangers such as iron core resonance, insulation breakdown and the like are avoided, and the safety is absolutely guaranteed.
(2) The detection process of the existing voltage transformer generally comprises the following steps: the method comprises the steps of electronic signal acquisition, analog signal transmission, primary conversion, a transmission system, secondary conversion and the like, and needs electronic signal acquisition equipment, analog signal transmission equipment, signal conversion equipment and the like, so that not only are more equipment needed and the cost high, but also interference is easily generated through line transmission, and the measurement precision is influenced. Compared with the existing equipment, the invention adopts an integrated detection structure, the electronic voltage transformer can directly obtain a detection voltage value, the display directly displays the electrified voltage of the high-voltage equipment after conversion, the detection equipment is simple, the transmission of a plurality of equipment is not needed, and the detection precision is high.
(3) The electronic voltage transformer has the advantages of small structure, simplified secondary wiring and convenience in installation and maintenance.
(4) The detected voltage signal is transmitted to the display in a digital mode, and the anti-interference capacity is high.
(5) The PT cabinet can be cancelled, the electric land is saved, and the user investment is saved.
It should be noted that, although the above embodiments have been described herein, the invention is not limited thereto. Therefore, based on the innovative concepts of the present invention, the technical solutions of the present invention can be directly or indirectly applied to other related technical fields by making changes and modifications to the embodiments described herein, or by using equivalent structures or equivalent processes performed in the content of the present specification and the attached drawings, which are included in the scope of the present invention.
Claims (10)
1. An induction display type electronic voltage mutual induction system is characterized in that: the display comprises a display and more than one electronic voltage transformer, wherein the display is electrically connected with each electronic voltage transformer; the electronic voltage transformer comprises a cylindrical insulating casting, wherein one end face of the insulating casting is provided with a first interface, the other end face of the insulating casting is provided with a second interface, a first spherical electrode is arranged in the insulating casting close to the first interface end and is electrically connected with one end of the first interface, and the other end of the first interface is electrically connected with a high-voltage bus in high-voltage equipment; a second spherical electrode and a signal processor are respectively arranged in the insulating casting close to the second interface end; one end of the signal processor is electrically connected with the second spherical electrode, and the other end of the signal processor is electrically connected with the display; the radius of the first spherical electrode is smaller than that of the second spherical electrode.
2. The induction display type electronic voltage transformer system according to claim 1, wherein: the radius of the first spherical electrode is 1-10mm, and the radius of the second spherical electrode is 20-30 mm.
3. The induction display type electronic voltage transformer system according to claim 1, wherein: and a voltage detection unit is arranged in the signal processor.
4. The induction display type electronic voltage transformer system according to claim 1, wherein: the minimum distance between the first spherical electrode and the second spherical electrode is greater than 10 mm.
5. The induction display type electronic voltage transformer system according to claim 1, wherein: the second interface is grounded, and the signal processor is grounded.
6. The induction display type electronic voltage transformer system according to claim 1, wherein: the number of the electronic voltage transformers is 1 or 3.
7. The induction display type electronic voltage transformer system according to claim 1, wherein: the insulating casting is an epoxy resin casting, a bakelite casting or a high-voltage silica gel casting.
8. The method for detecting voltage of an induction display type electronic voltage transformer system according to any one of claims 1 to 7, wherein: the method comprises the following steps:
1) the other end of the first interface of the electronic voltage transformer is electrically connected with a high-voltage bus in high-voltage equipment, and the electronic voltage transformer is arranged in the high-voltage equipment through the second interface to be used as a support of the high-voltage bus;
2) when the high-voltage equipment is in a power-on state, the high-voltage bus forms a high-voltage electric field; the first spherical electrode and the second spherical electrode are both spherical and are electrically connected with the high-voltage bus bar, so that an uneven electric field is formed by the first spherical electrode and the second spherical electrode; in the formed uneven electric field, the surface of the first spherical electrode has stronger electric field intensity because the curvature radius of the first spherical electrode is smaller than that of the second spherical electrode; under the action of the strong electric field intensity, an ionized layer is generated in a micron-sized area away from the surface of the first spherical electrode, so that a migration current is formed between the first spherical electrode and the second spherical electrode;
3) the signal processor detects the voltage corresponding to the migration current on the second spherical electrode, the voltage corresponding to the migration current is positively correlated with the electrified voltage of the high-voltage busbar, so that the detected voltage value is converted into an electrified voltage signal of the high-voltage busbar, and the signal processor sends the processed voltage signal to the display.
9. The method for detecting voltage of an induction display type electronic voltage transformer system according to claim 8, wherein: the voltage signal obtained by the signal processor comprises a voltage effective value signal and a voltage analog signal.
10. The method for detecting voltage of an induction display type electronic voltage transformer system according to claim 8, wherein: and a resistor is arranged in the signal processor, the resistor is electrically connected with the second spherical electrode, and the voltage value of the migration current is measured through the resistor.
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| CN201810014316.4A CN108205073B (en) | 2018-01-08 | 2018-01-08 | Induction display type electronic voltage mutual induction system and voltage detection method thereof |
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| CN201810014316.4A CN108205073B (en) | 2018-01-08 | 2018-01-08 | Induction display type electronic voltage mutual induction system and voltage detection method thereof |
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| CN108205073B true CN108205073B (en) | 2020-04-24 |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202093079U (en) * | 2010-12-09 | 2011-12-28 | 广东中钰科技有限公司 | Electronic type voltage transformer based on coaxial differential pressure |
| CN203465343U (en) * | 2013-07-20 | 2014-03-05 | 福州新益自动测控设备有限公司 | High-precision high-voltage sensor in high-voltage equipment |
| CN204793619U (en) * | 2015-05-20 | 2015-11-18 | 云南电网有限责任公司玉溪供电局 | Switching device discharges in intelligence ball crack |
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- 2018-01-08 CN CN201810014316.4A patent/CN108205073B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202093079U (en) * | 2010-12-09 | 2011-12-28 | 广东中钰科技有限公司 | Electronic type voltage transformer based on coaxial differential pressure |
| CN203465343U (en) * | 2013-07-20 | 2014-03-05 | 福州新益自动测控设备有限公司 | High-precision high-voltage sensor in high-voltage equipment |
| CN204793619U (en) * | 2015-05-20 | 2015-11-18 | 云南电网有限责任公司玉溪供电局 | Switching device discharges in intelligence ball crack |
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| CN108205073A (en) | 2018-06-26 |
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