CN112684236A - Voltage transformer - Google Patents
Voltage transformer Download PDFInfo
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- CN112684236A CN112684236A CN202011389778.8A CN202011389778A CN112684236A CN 112684236 A CN112684236 A CN 112684236A CN 202011389778 A CN202011389778 A CN 202011389778A CN 112684236 A CN112684236 A CN 112684236A
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Abstract
The invention discloses a voltage transformer which comprises N metal electrodes, N-1 crystals respectively arranged between every two adjacent metal electrodes, and a dual-mode optical fiber and light source detection module wound on the N-1 crystals. Specifically, the crystal can be deformed under the action of the voltage to be measured, when the crystal is deformed, two conduction modes of the dual-mode optical fiber wound on the crystal can generate a phase difference, and the light source detection module calculates the voltage to be measured based on the phase difference. Therefore, the optical fiber is adopted to transmit signals, the insulating capacity of the voltage transformer is improved due to the fact that the optical fiber has good insulating performance, electromagnetic interference cannot be generated due to the use of the optical fiber, ferromagnetic resonance cannot be generated, and the safety of a power grid is improved.
Description
Technical Field
The invention relates to the field of voltage measurement, in particular to a voltage transformer.
Background
The voltage division module among traditional voltage transformer is resistance voltage division module or resistance-capacitance voltage division module, and resistance voltage division module and resistance-capacitance voltage division module can realize the high accuracy measurement to electric wire netting voltage, but, along with the electric wire netting to the trend development of superhigh pressure and large capacity, traditional voltage transformer is insulating the difficulty under the condition of high pressure and superhigh pressure, ferromagnetic resonance probably takes place, has the phenomenon of body magnetic saturation, ferromagnetic resonance, causes the threat to the security of electric wire netting.
Disclosure of Invention
The invention aims to provide a voltage transformer, which improves the insulating capability of the voltage transformer, does not generate electromagnetic interference, namely ferromagnetic resonance, and improves the safety of a power grid.
In order to solve the technical problem, the invention provides a voltage transformer which is applied to a power grid and comprises:
the N metal electrodes and the N-1 crystals which are sequentially connected from the high-voltage end of the power grid to the low-voltage end of the ground are respectively arranged between every two adjacent metal electrodes and are used for generating deformation under the action of voltage to be measured, N is not less than 2, and the voltage to be measured is the output voltage of the power grid;
the double-mode optical fiber is used for enabling two self conduction modes to generate phase difference when the crystals deform;
the light source detection module is used for calculating the voltage to be detected based on the phase difference between the two conduction modes of the dual-mode optical fiber.
Preferably, one end of the double-mode optical fiber is uniformly wound on N-1 crystals respectively.
Preferably, the crystal is a quartz crystal.
Preferably, the crystal is a ceramic piezoelectric crystal.
Preferably, the light source detection module is a receiving interferometer.
Preferably, the device further comprises an insulating tube, wherein N metal electrodes and N-1 crystals are arranged in the insulating tube.
Preferably, the insulating tube further comprises flanges respectively arranged at two ends of the insulating tube.
Preferably, the insulation tube further comprises an insulation sleeve arranged outside the insulation tube.
Preferably, the outer side surface of the insulation sleeve is tapered from bottom to top.
Preferably, the insulating sleeve is provided in plurality.
The application provides a voltage transformer which comprises N metal electrodes, N-1 crystals respectively arranged between every two metal electrodes, and a dual-mode optical fiber and light source detection module wound on the N-1 crystals. Specifically, the crystal can be deformed under the action of the voltage to be measured, when the crystal is deformed, two conduction modes of the dual-mode optical fiber wound on the crystal can generate a phase difference, and the light source detection module calculates the voltage to be measured based on the phase difference. Therefore, the optical fiber is adopted to transmit signals, the insulating capacity of the voltage transformer is improved due to the fact that the optical fiber has good insulating performance, electromagnetic interference cannot be generated due to the use of the optical fiber, ferromagnetic resonance cannot be generated, and the safety of a power grid is improved.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed in the prior art and the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a voltage transformer provided by the present invention;
fig. 2 is a schematic structural diagram of a voltage transformer in the prior art according to the present invention;
fig. 3 is a schematic structural diagram of another prior art voltage transformer provided by the present invention;
fig. 4 is a schematic structural diagram of a voltage transformer according to the present invention;
fig. 5 is a schematic structural diagram of another voltage transformer provided by the present invention.
Detailed Description
The core of the invention is to provide the voltage transformer, which improves the insulating capability of the voltage transformer, does not generate electromagnetic interference, namely ferromagnetic resonance, and improves the safety of a power grid.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a voltage transformer provided in the present invention, the voltage transformer is applied to a power grid, and includes:
the double-mode optical fiber 3 is used for enabling two self conduction modes to generate phase difference when the crystal 2 deforms;
and the light source detection module 4 is used for calculating the voltage to be detected based on the phase difference between the two conduction modes of the dual-mode optical fiber 3.
The high-voltage direct-current voltage measuring device is important equipment for voltage measurement in an extra-high-voltage direct-current transmission system and a flexible direct-current transmission system, is arranged at a direct-current limit, a valve bank and a neutral line, and the measuring result is closely related to the reliability of direct-current transmission. Referring to fig. 2 and 3, fig. 2 is a schematic structural diagram of a voltage transformer in the prior art provided by the present invention, and fig. 3 is a schematic structural diagram of another voltage transformer in the prior art provided by the present invention, a conventional electromagnetic or capacitive voltage-dividing voltage transformer in the prior art is difficult to insulate under high voltage and extra high voltage conditions, and at this time, the voltage transformer is bridged in a power grid to be equivalent to a nonlinear inductive load, and may act with a capacitor in a system to generate a phenomenon of ferromagnetic resonance, ferromagnetic saturation or ferromagnetic resonance, thereby threatening the safety of the power grid.
In order to solve the above technical problems, it is necessary to provide a voltage transformer with good insulation property for voltage measurement in a dc power transmission system. The design idea of this application is better for considering the insulating nature of optic fibre, uses optic fibre transmission signal can improve voltage transformer's insulating ability, in addition, still considers that optic fibre intermode interference technique has simple structure and inherent anti ambient temperature's ability, consequently is applied to voltage transformer with carry out the voltage measurement of direct current transmission system in.
Based on this, the voltage transformer in this application includes N metal electrodes 1, N-1 that connect gradually from the high voltage end of electric wire netting to ground low voltage end and set up crystal 2, bimodulus optic fibre 3 and light source detection module 4 between every two adjacent metal electrodes 1 respectively, specifically, the number of metal electrode 1 and the number of crystal 2 are decided by the size of the voltage of measuring, and the voltage is bigger, and the number of crystal 2 and metal electrode 1 is more, and N metal electrode 1 and N-1 crystal 2 play the partial pressure and measure the electric wire netting voltage. The voltage of the high-voltage end of the power grid is output to the ground low-voltage end through the metal electrode 1 and the crystal 2, and the crystal 2 has the inverse piezoelectric effect, so that the crystal 2 deforms under the action of the voltage to be measured (namely the output voltage of the power grid), the phase difference of two conduction modes in the dual-mode optical fiber 3 wound on the crystal 2 changes, and finally the measured voltage is calculated through the phase difference between the two conduction modes in the dual-mode optical fiber 3 of the light source detection module 4.
The metal electrode 1 in the present application may be, but is not limited to, a metal electrode 1. Referring to fig. 4, fig. 4 is a schematic diagram of a specific structure of a voltage transformer provided by the present invention, in the present application, the number of the metal electrodes 1 is 4, and the number of the crystals 2 is 3, and of course, the number of the metal electrodes 1 and the number of the crystals 2 are not limited to the above example, and may be other numbers, which is determined according to the actual situation, and the present application is not particularly limited herein.
In conclusion, the optical fiber is adopted to transmit signals, the optical fiber has good insulating property, so that the insulating capability of the voltage transformer is improved, electromagnetic interference cannot be generated by using the optical fiber, ferromagnetic resonance cannot be generated, and the safety of a power grid is improved.
On the basis of the above-described embodiment:
as a preferred embodiment, one end of the double-mode optical fiber 3 is uniformly wound on N-1 crystals 2, respectively.
In the embodiment, the dual-mode optical fiber 3 is sequentially and uniformly wound on the N-1 crystals 2, and in order to ensure the measurement accuracy, one end of the dual-mode optical fiber 3 is uniformly wound on each crystal 2 under the equal tension, so that the measurement accuracy and reliability of the voltage to be measured are improved, and the safety of a power grid is ensured.
As a preferred embodiment, the crystal 2 is a quartz crystal.
The embodiment aims to provide a specific implementation manner of the crystal 2, specifically, the crystal 2 in the present application may be a quartz crystal, and the quartz crystal has a strong inverse piezoelectric effect, and can generate deformation under the action of the voltage to be measured, so that a phase difference is generated between two conduction modes of the dual-mode optical fiber 3, and the measurement of the voltage to be measured can be realized. In addition, the quartz crystal also has excellent electrical characteristics and temperature characteristics, the linearity is higher, and the measurement accuracy is improved.
Of course, the crystal 2 in the present application is not limited to a quartz crystal, and may also be another crystal 2 having an inverse piezoelectric effect and capable of generating deformation under the action of the voltage to be measured, and the present application is not limited thereto.
As a preferred embodiment, the crystal 2 is a ceramic piezoelectric crystal.
The embodiment aims to provide a specific implementation manner of the crystal 2, specifically, the crystal 2 in the present application may be a ceramic piezoelectric crystal, and the ceramic piezoelectric crystal has an inverse piezoelectric effect, and can generate deformation under the effect of the voltage to be measured, so that a phase difference is generated between two conduction modes of the dual-mode optical fiber 3, and the measurement of the voltage to be measured can be realized.
Of course, the crystal 2 in the present application is not limited to a ceramic piezoelectric crystal, and may also be another crystal 2 having an inverse piezoelectric effect and capable of generating deformation under the action of the voltage to be measured, and the present application is not limited thereto.
As a preferred embodiment, the light source detection module 4 is a receiving interferometer.
In this embodiment, the light source detection module 4 may be, but is not limited to, a receiving interferometer, wherein the other end of the dual-mode optical fiber 3 is connected to the receiving interferometer, and the receiving interferometer may calculate the intensity of the voltage to be measured according to the phase difference between the two conducting modes of the dual-mode optical fiber 3.
Of course, the light source detection module 4 in the present application is not limited to a receiving interferometer, and may also be other instruments that can calculate the intensity of the voltage to be measured according to the phase difference between two conducting modes of the dual-mode optical fiber 3, and the present application is not limited thereto.
Referring to fig. 5, fig. 5 is a schematic structural diagram of another voltage transformer provided by the present invention.
As a preferred embodiment, the device also comprises an insulating tube 5, wherein N metal electrodes 1 and N-1 crystals 2 are arranged in the insulating tube 5.
Considering that the voltage transformer generally works in a high-voltage strong-current working environment, the metal electrode 1 and the crystal 2 are easily subjected to electromagnetic interference, thereby threatening the safety of a power grid. In order to solve the above technical problem, an insulating device needs to be provided for the voltage transformer to improve the insulation of the voltage transformer. Based on this, this application has still set up insulating tube 5 to arrange N metal electrode 1 and N-1 crystal 2 in insulating tube 5, can improve voltage transformer's insulating ability through insulating tube 5 not only, but also play the mechanical protection effect to voltage transformer, improved voltage transformer's measuring security and reliability.
The insulating tube 5 in the present application may be a glass fiber tube, but is not limited to a glass fiber tube, and may be another insulating tube 5 having an insulating function.
As a preferred embodiment, the insulating tube further comprises flanges 6 respectively disposed at both ends of the insulating tube 5.
When the voltage transformer measures the voltage to be measured, the voltage transformer is generally fixed at a certain position in a power grid, therefore, the flange plates 6 are further arranged at the two ends of the insulating pipe 5 and used for fixing and/or connecting the voltage transformer in the power grid, and the connectivity and the stability of the voltage transformer are improved. The specific shape of the flange 6 is determined according to actual requirements, and the application is not particularly limited herein.
As a preferred embodiment, it further comprises an insulating sleeve 7 arranged outside the insulating tube 5.
In consideration of the fact that the voltage transformer works in the high-voltage direct-current environment of a power grid and can possibly be subjected to electromagnetic interference, in order to solve the technical problem, the insulating sleeve 7 is further arranged outside the insulating tube 5, the effect of high-voltage insulation is achieved, and the working safety of the voltage transformer is improved.
Specifically, insulating cover 7 in this application can be the silicon rubber cover, and the silicon rubber cover can realize insulating function of insulating cover 7 in this application, and the silicon rubber cover still has performances such as fire prevention and, high temperature resistant, withstand voltage, resistant electric arc and corona performance, and in high voltage electric network's environmental nature and stability, improves voltage transformer's reliability of working, prevents that it from connecting or producing electric arc etc..
Of course, the insulating sleeve 7 in the present application is not limited to the above example, and may be another insulating sleeve 7, and the present application is not particularly limited thereto.
As a preferred embodiment, the outer side of the insulating sleeve 7 tapers from bottom to top.
Considering that the voltage transformer generally works outdoors when measuring the voltage of the power grid, at the moment, dirt (such as air, dust, rainwater and the like) in the air can be attached to the surface of the voltage transformer to form a conductive medium, so that the insulating capability of the voltage transformer is reduced, and the safety and the reliability of the voltage transformer are greatly reduced when the voltage transformer works outdoors.
For solving above-mentioned technical problem, this application is for increasing voltage transformer's dielectric strength to increase creepage distance, specifically, set up the lateral surface of insulating cover 7 into the shape of convergent from bottom to top, be similar to the shape of shirt rim, through the mode in this application, to the filthy medium in the air, conductive medium such as dust and rainwater is difficult to switch on promptly, thereby increase voltage transformer's dielectric strength, guarantee security and the reliability of voltage transformer during operation.
In a preferred embodiment, the insulating sheath 7 is provided in plurality.
Specifically, for further increase voltage transformer's dielectric strength, insulating cover 7 in this application is a plurality of, sets gradually a plurality of insulating covers 7 from the upper end to the lower extreme of the outside of insulating tube 5 in voltage transformer, further increases creepage distance to improve voltage transformer's dielectric strength.
Wherein, a plurality of insulating cover 7 can be the lateral surface from bottom to top convergent shape, and a plurality of insulating cover 7 size can be the same also can not be the same, and this application does not do special restriction to insulating cover 7's number and size here, specifically according to actual conditions and decide.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
It is further noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A voltage transformer is applied to a power grid and is characterized by comprising:
the N metal electrodes and the N-1 crystals which are sequentially connected from the high-voltage end of the power grid to the low-voltage end of the ground are respectively arranged between every two adjacent metal electrodes and are used for generating deformation under the action of voltage to be measured, N is not less than 2, and the voltage to be measured is the output voltage of the power grid;
the double-mode optical fiber is used for enabling two self conduction modes to generate phase difference when the crystals deform;
the light source detection module is used for calculating the voltage to be detected based on the phase difference between the two conduction modes of the dual-mode optical fiber.
2. The voltage transformer of claim 1, wherein one end of the dual mode fiber is uniformly wound around N-1 of the crystals, respectively.
3. The voltage transformer of claim 1, wherein the crystal is a quartz crystal.
4. The voltage transformer of claim 1, wherein the crystal is a ceramic piezoelectric crystal.
5. The voltage transformer of claim 1, wherein the light source detection module is a receive interferometer.
6. The voltage transformer according to any one of claims 1-5, further comprising an insulating tube, wherein N of said metal electrodes and N-1 of said crystals are disposed within said insulating tube.
7. The voltage transformer according to any one of claims 1 to 5, further comprising flanges respectively provided at both ends of the insulating tube.
8. The voltage transformer of claim 7, further comprising an insulating sleeve disposed outside the insulating tube.
9. The voltage transformer of claim 8, wherein an outer side of the insulating sheath is tapered from bottom to top.
10. The voltage transformer of claim 9, wherein the insulating sheath is plural.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011389778.8A CN112684236A (en) | 2020-12-02 | 2020-12-02 | Voltage transformer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011389778.8A CN112684236A (en) | 2020-12-02 | 2020-12-02 | Voltage transformer |
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| CN112684236A true CN112684236A (en) | 2021-04-20 |
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2020
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Application publication date: 20210420 |