CN111239472B - An overvoltage monitoring sensor - Google Patents
An overvoltage monitoring sensor Download PDFInfo
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- CN111239472B CN111239472B CN202010082589.XA CN202010082589A CN111239472B CN 111239472 B CN111239472 B CN 111239472B CN 202010082589 A CN202010082589 A CN 202010082589A CN 111239472 B CN111239472 B CN 111239472B
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- 238000012544 monitoring process Methods 0.000 title claims abstract description 15
- 239000003990 capacitor Substances 0.000 claims abstract description 14
- 239000000523 sample Substances 0.000 claims description 27
- 238000012545 processing Methods 0.000 claims description 12
- 230000005540 biological transmission Effects 0.000 claims description 11
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 6
- 229910052802 copper Inorganic materials 0.000 claims description 6
- 239000010949 copper Substances 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 3
- 230000001939 inductive effect Effects 0.000 claims description 2
- 238000012805 post-processing Methods 0.000 abstract description 4
- 238000007599 discharging Methods 0.000 abstract description 3
- 230000008093 supporting effect Effects 0.000 description 19
- 238000009413 insulation Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 230000015556 catabolic process Effects 0.000 description 3
- 230000006378 damage Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000001976 improved effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011897 real-time detection Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16504—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the components employed
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- Emergency Protection Circuit Devices (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The application provides an overvoltage monitoring sensor, the technical scheme base that this application shows constitutes the electric capacity, and support column and inductance coils constitute the inductance, and the support plane is the resistance, constitutes a power frequency trapper. The power frequency wave trap circuit is actually an RLC series circuit, the voltage of a capacitor and the voltage of an inductor of the power frequency wave trap circuit are combined to be used as output voltage, the capacitor is an open circuit for direct current, the power frequency wave trap circuit is in a conducting state only due to the charging and discharging properties of the alternating current, and the impedance presented by the alternating current is smaller when the alternating current frequency is higher. Inductance is a path to direct current in which an induced voltage is generated due to faraday's law, and presents a higher impedance at higher alternating frequencies. The power frequency trap that RLC series connection constitutes, power frequency signal short circuit ground connection, and high frequency signal opens a way to ground, consequently, can detect high frequency overvoltage signal, and can not respond to the power frequency high pressure, help post processing circuit safety and personal safety.
Description
Technical Field
The invention relates to the field of on-line monitoring of power equipment, in particular to an overvoltage monitoring sensor.
Background
With the continuous development of economy and the continuous increase of power load, the power grid structure is increasingly complex, and no matter a transformer substation or a line can be subjected to various overvoltage accidents frequently, so that the insulation breakdown of electrical equipment and the power supply interruption are caused, and the reliability of power supply is seriously influenced. Operation experience and research show that the safe, reliable and stable operation of the power system is closely related to the insulation level and the overvoltage magnitude.
The overvoltage types in the power system are various, and the generation reasons are different. Overvoltages can be divided into two general categories, namely external overvoltages and internal overvoltages. The external overvoltage is the lightning overvoltage. Thunder is a gas discharge phenomenon in nature, and lightning current generated by thundercloud discharge can reach tens of thousands of amperes, even hundreds of thousands of amperes, so that high lightning overvoltage is caused in a power system, and the lightning current is one of main reasons for causing insulation accidents of the power system and seriously harms the safe operation of the power system. The lightning overvoltage is characterized by high voltage amplitude, short duration and large rising gradient, so that the lightning overvoltage has great harm to electrical equipment.
Internal overvoltages are generated in the system during the transition of conversion or transfer of electromagnetic energy inside the power system caused by changes in system parameters due to operation of circuit breakers or system faults. The internal overvoltage lasts for a long time, and the breakdown voltage is smaller than the lightning breakdown voltage, which also causes serious damage to the power equipment. The internal overvoltage is generally classified into an operation overvoltage and a temporary overvoltage according to the cause of generation. The general duration of the operation overvoltage is within 100 ms; the temporary overvoltage comprises resonance overvoltage and power frequency voltage rise, and the temporary overvoltage is mainly caused by capacitance effect of a no-load long line, asymmetric earth fault, sudden load change, linear or nonlinear resonance which may occur in a system and the like, and has relatively long duration. Although most of the overvoltage has smaller amplitude and shorter duration, the overvoltage does not cause obvious damage to the system. However, when an overvoltage seriously harming the system safety occurs, in order to facilitate operation managers to analyze and search fault causes in time, an improved insulation matching method is provided, and real-time detection is necessary for the power system. When a signal generated by overvoltage is processed, working frequency and high voltage can be induced, and an electric shock can occur to a worker in the later signal processing process, so that the life safety of the worker is endangered.
Disclosure of Invention
The technical scheme shown in the embodiment of the application aims to provide an overvoltage monitoring sensor so as to protect the personal safety of workers in the signal processing process.
The application provides an overvoltage monitoring sensor, includes: the device comprises a base, a support column, an inductance coil, a support plane, a sensor probe, a transmission line and a signal processing terminal;
the base is sequentially provided with a first conducting layer, an insulating medium and a second conducting layer from bottom to top;
the base is connected with the supporting column;
the outer surface of the supporting column is sequentially wound by the inductance coil;
the upper end and the lower end of the inductance coil are respectively connected with the base and the supporting plane;
the top end of the supporting plane is connected with the output end of the sensor probe;
and the connection part of the bottom of the support plane and the inductance coil transmits signals to a signal processing terminal by using a transmission line.
Optionally, the device further comprises a probe shell, and the sensor probe is fixed at the top end of the support plane through the probe shell.
Optionally, the support plane is a resistor.
Optionally, a tapered sensor probe is provided inside the sensor probe for monitoring an overvoltage signal that may be generated.
Optionally, the first conductive layer is a copper plate, and the second conductive layer is a copper plate.
Optionally, the capacitance of the base satisfies the formula
Wherein epsilon is the dielectric constant of the insulating medium, S is the area of the first conductive layer, the area of the first conductive layer is equal to the area of the second conductive layer, and d is the distance between the first conductive layer and the second conductive layer.
Alternatively, the support posts are hollow, dielectric posts with an external inductor coil wrapped around them to form an inductor.
According to the above technical solution, the present application provides an overvoltage monitoring sensor, including: the device comprises a base, a support column, an inductance coil, a support plane, a sensor probe, a transmission line and a signal processing terminal; the base is sequentially provided with a first conducting layer, an insulating medium and a second conducting layer from bottom to top; the base is connected with the supporting column; the outer surface of the supporting column is sequentially wound by the inductance coil; the upper end and the lower end of the inductance coil are respectively connected with the base and the supporting plane; the top end of the supporting plane is connected with the output end of the sensor probe; and the connection part of the bottom of the support plane and the inductance coil transmits signals to a signal processing terminal by using a transmission line. The technical scheme base that this application shows constitutes the electric capacity, and support column and inductance coils constitute the inductance, and the supporting plane is the resistance, constitutes a power frequency trapper. The power frequency wave trap circuit is actually an RLC series circuit, the voltage of a capacitor and the voltage of an inductor of the power frequency wave trap circuit are combined to be used as output voltage, the capacitor is an open circuit for direct current, the power frequency wave trap circuit is in a conducting state only due to the charging and discharging properties of the alternating current, and the impedance presented by the alternating current is smaller when the alternating current frequency is higher. Inductance is a path to direct current in which an induced voltage is generated due to faraday's law, and presents a higher impedance at higher alternating frequencies.
The RLC series circuit has large capacitance impedance at low frequency, no effect on inductor L, capacitor voltage Vout as output voltage Vout, and large inductance impedance at high frequencyThe capacitor C is not active and the output voltage Vout is almost the inductor voltage. The frequency is moderate, namely:
when the capacitance reactance is equal to the inductance reactance, the voltages of the capacitance and the inductance are just in opposite phases and are mutually offset. The power frequency trap that RLC series connection constitutes, power frequency signal short circuit ground connection, and high frequency signal opens a way to ground, consequently, can detect high frequency overvoltage signal, and can not respond to the power frequency high pressure, help post processing circuit safety and personal safety.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in 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 illustrates an overvoltage monitoring sensor in accordance with a preferred embodiment;
FIG. 2 is a schematic diagram illustrating the assembly of a support post and an inductor coil in accordance with a preferred embodiment;
FIG. 3 is a schematic structural view of a support plane shown in accordance with a preferred embodiment;
fig. 4 is an equivalent circuit of the overvoltage monitoring sensor according to a preferred embodiment.
The device comprises a base 1, a first conducting layer 11, an insulating medium 12, a second conducting layer 13, a supporting column 2, an inductance coil 3, a supporting plane 4, a sensor probe 5, a probe shell 6, a transmission line 7 and a signal processing terminal 8.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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, an embodiment of the present application provides an overvoltage monitoring sensor, which is characterized in that: the method comprises the following steps: the device comprises a base 1, a support column 2, an inductance coil 3, a support plane 4, a sensor probe 5, a transmission line 7 and a signal processing terminal 8;
the base 1 is sequentially provided with a first conducting layer 11, an insulating medium 12 and a second conducting layer 13 from bottom to top;
the base 1 is connected with the support column 2;
the outer surface of the supporting column 2 is sequentially wound by the inductance coil 3;
the upper end and the lower end of the inductance coil 3 are respectively connected with the base 1 and the supporting plane 4;
the top end of the supporting plane 4 is connected with the output end of the sensor probe 5;
the connection between the bottom of the support plane 4 and the inductor 3 is transmitted to a signal processing terminal 8 by a transmission line 7.
Referring to fig. 2, the first conductive layer 11 is a copper plate, and the second conductive layer 13 is a copper plate.
The insulating medium 12 consists of three layers of flat plates which form a parallel plate capacitor. The capacitance of the parallel plate capacitor satisfies the formula
Where ε is the dielectric constant of the insulating medium 12, S is the area of the first conductive layer, which is equal to the area of the second conductive layer, and d is the spacing between the first conductive layer and the second conductive layer.
The support plane 4 is a special material to form a resistor, and the corresponding resistance formula is
Where ρ is the resistivity (in ohm-cm) of the resistive material; l is the length of the resistor body (cm); a is a sectional area (square centimeter) of the resistor body.
Referring to fig. 3, the support column 2 is an insulating hollow column around which an inductor coil 3 is wound to form an inductor.
Referring to fig. 4, the base 1 forms a capacitor, the support column 2 and the inductance coil 3 form an inductor, and the support plane 4 is a resistor, so as to form a power frequency trap.
The power frequency wave trap is an RLC series circuit, and the trap frequency formed by LC meets the corresponding formula:
at the moment, the capacitive reactance is equal to the inductive reactance, the voltage of the capacitor and the voltage of the inductor are in opposite phases and are mutually offset, so that a power frequency wave trap is formed, the power frequency signal is in short circuit and grounded, and the high-frequency signal is in open circuit to the ground, therefore, the high-frequency overvoltage signal can be detected, the high-frequency high voltage cannot be induced, and the safety of a post-processing circuit and the personal safety are facilitated.
Optionally, the device further comprises a probe shell 6, and the sensor probe 5 is fixed at the top end of the support plane 4 through the probe shell 6.
Optionally, a tapered sensor probe is provided inside the sensor probe 5 for monitoring the overvoltage signal that may be generated.
Alternatively, the support column 2 is an insulated hollow column around which an inductor coil 3 is wound to form an inductor.
The application provides an overvoltage monitoring sensor, includes: the device comprises a base, a support column, an inductance coil, a support plane, a sensor probe, a transmission line and a signal processing terminal; the base is sequentially provided with a first conducting layer, an insulating medium and a second conducting layer from bottom to top; the base is connected with the supporting column; the outer surface of the supporting column is sequentially wound by the inductance coil; the upper end and the lower end of the inductance coil are respectively connected with the base and the supporting plane; the top end of the supporting plane is connected with the output end of the sensor probe; and the connection part of the bottom of the support plane and the inductance coil transmits signals to a signal processing terminal by using a transmission line. The technical scheme base that this application shows constitutes the electric capacity, and support column and inductance coils constitute the inductance, and the supporting plane is the resistance, constitutes a power frequency trapper. The power frequency wave trap circuit is actually an RLC series circuit, the voltage of a capacitor and the voltage of an inductor of the power frequency wave trap circuit are combined to be used as output voltage, the capacitor is an open circuit for direct current, the power frequency wave trap circuit is in a conducting state only due to the charging and discharging properties of the alternating current, and the impedance presented by the alternating current is smaller when the alternating current frequency is higher. Inductance is a path to direct current in which an induced voltage is generated due to faraday's law, and presents a higher impedance at higher alternating frequencies.
In the RLC series circuit, the capacitance resistance is large when the frequency is low, the inductor L does not act, the output voltage Vout is the capacitance voltage, the inductance resistance is large when the frequency is high, the capacitor C does not act, and the output voltage Vout is almost the inductance voltage. The frequency is moderate, namely:
when the capacitance reactance is equal to the inductance reactance, the voltages of the capacitance and the inductance are just in opposite phases and are mutually offset. The power frequency trap that RLC series connection constitutes, power frequency signal short circuit ground connection, and high frequency signal opens a way to ground, consequently, can detect high frequency overvoltage signal, and can not respond to the power frequency high pressure, help post processing circuit safety and personal safety.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.
It will be understood that the invention is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.
Claims (6)
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1908681A (en) * | 2006-08-15 | 2007-02-07 | 重庆大学 | Over-voltage monitoring sensor for AD electricity system |
| CN101666826A (en) * | 2009-09-27 | 2010-03-10 | 陕西电力科学研究院 | Overvoltage online monitoring device based on dual time base sampling technology |
| CN104061851A (en) * | 2014-07-03 | 2014-09-24 | 重庆大学 | Method for online monitoring deformation of transformer winding based on over-voltage response |
| JP2015040799A (en) * | 2013-08-22 | 2015-03-02 | 富士電機株式会社 | Power supply circuit device, curent measurement device, power monitoring system, and method for protecting power supply circuit device |
| CN105098726A (en) * | 2015-09-15 | 2015-11-25 | 李梦菲 | Overvoltage rapid protection circuit and method for series capacitor of power system |
| CN105137158A (en) * | 2015-07-24 | 2015-12-09 | 上海君世电气科技有限公司 | Power system temporary overvoltage monitoring system |
| CN206096245U (en) * | 2016-10-25 | 2017-04-12 | 云南电网有限责任公司电力科学研究院 | Two difference formula D dot crosses voltage sensor and monitoring system |
| KR20190073142A (en) * | 2017-12-18 | 2019-06-26 | 엘지전자 주식회사 | Protection circuit of switchs of power converting apparatus and operating method thereof |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101581738B (en) * | 2009-06-24 | 2010-12-08 | 重庆大学 | Overvoltage Sensors for Overhead Transmission Lines |
| CN102998556B (en) * | 2012-10-29 | 2016-02-24 | 中国电力科学研究院 | The very fast transient overvoltage simulator of metal oxide pressure-limiting device and method thereof |
| CN203299264U (en) * | 2013-04-27 | 2013-11-20 | 国家电网公司 | Overvoltage on-line monitor system |
| CN203455399U (en) * | 2013-09-23 | 2014-02-26 | 国家电网公司 | A CVT transient overvoltage sensor |
| CN203445611U (en) * | 2013-09-28 | 2014-02-19 | 成都星河科技产业有限公司 | Lightning protection over-voltage isolator |
| CN104518475B (en) * | 2013-09-28 | 2017-04-05 | 成都星河科技产业有限公司 | A kind of distribution Integrated Lightning protection System |
| CN204793996U (en) * | 2014-12-31 | 2015-11-18 | 国家电网公司 | A metallic sheath circulation inhibitor for single core power cable cross -bonding section |
| CN204882701U (en) * | 2015-08-12 | 2015-12-16 | 中国南方电网有限责任公司电网技术研究中心 | Non -contact crosses voltage sensor |
| CN205562668U (en) * | 2016-04-14 | 2016-09-07 | 云南电网有限责任公司电力科学研究院 | Transformer substation is with simple and easy type overvoltage on -line monitoring device |
| CN206161728U (en) * | 2016-11-18 | 2017-05-10 | 云南电网有限责任公司电力科学研究院 | Transmission line overvoltage monitoring system |
| CN206193087U (en) * | 2016-11-28 | 2017-05-24 | 三峡大学 | Non -contact overvoltage monitoring device based on electroluminescent effect |
| CN207232234U (en) * | 2017-10-16 | 2018-04-13 | 云南电网有限责任公司电力科学研究院 | A kind of special fast transient overvoltage measuring system |
| CN109709381A (en) * | 2019-03-13 | 2019-05-03 | 清华四川能源互联网研究院 | A portable substation transient overvoltage real-time monitoring device |
-
2020
- 2020-02-07 CN CN202010082589.XA patent/CN111239472B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1908681A (en) * | 2006-08-15 | 2007-02-07 | 重庆大学 | Over-voltage monitoring sensor for AD electricity system |
| CN101666826A (en) * | 2009-09-27 | 2010-03-10 | 陕西电力科学研究院 | Overvoltage online monitoring device based on dual time base sampling technology |
| JP2015040799A (en) * | 2013-08-22 | 2015-03-02 | 富士電機株式会社 | Power supply circuit device, curent measurement device, power monitoring system, and method for protecting power supply circuit device |
| CN104061851A (en) * | 2014-07-03 | 2014-09-24 | 重庆大学 | Method for online monitoring deformation of transformer winding based on over-voltage response |
| CN105137158A (en) * | 2015-07-24 | 2015-12-09 | 上海君世电气科技有限公司 | Power system temporary overvoltage monitoring system |
| CN105098726A (en) * | 2015-09-15 | 2015-11-25 | 李梦菲 | Overvoltage rapid protection circuit and method for series capacitor of power system |
| CN206096245U (en) * | 2016-10-25 | 2017-04-12 | 云南电网有限责任公司电力科学研究院 | Two difference formula D dot crosses voltage sensor and monitoring system |
| KR20190073142A (en) * | 2017-12-18 | 2019-06-26 | 엘지전자 주식회사 | Protection circuit of switchs of power converting apparatus and operating method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 35kV变电站过电压在线监测及波形分析;陈鑫 等;《电气技术》;20160415;第115-118页 * |
| Research on Overvoltage Distribution of HVDC Converter Valve and Influence of Parasitic Capacitance in special environment;Cuicui Liu 等;《2019 IEEE 10th International Symposium on Power Electronics for Distributed Generation Systems (PEDG)》;20191231;第178-182页 * |
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Effective date of registration: 20241226 Address after: 650000 Kunming Economic and Technological Development Zone, Yunnan Province Patentee after: YUNNAN ELECTRIC POWER TEST & RESEARCH INSTITUTE (GROUP) Co.,Ltd. Country or region after: China Address before: 650217 No. 105 Yunda West Road, Kunming Economic and Technological Development Zone, Yunnan Province Patentee before: ELECTRIC POWER RESEARCH INSTITUTE, YUNNAN POWER GRID Co.,Ltd. Country or region before: China |
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