CN201853571U - Voltage transformer based on capacitance-resistance voltage division principle - Google Patents
Voltage transformer based on capacitance-resistance voltage division principle Download PDFInfo
- Publication number
- CN201853571U CN201853571U CN2010205715652U CN201020571565U CN201853571U CN 201853571 U CN201853571 U CN 201853571U CN 2010205715652 U CN2010205715652 U CN 2010205715652U CN 201020571565 U CN201020571565 U CN 201020571565U CN 201853571 U CN201853571 U CN 201853571U
- Authority
- CN
- China
- Prior art keywords
- field electrode
- electrode
- low
- voltage
- transducer
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Transformers For Measuring Instruments (AREA)
Abstract
The utility model relates to a voltage transformer based on the capacitance-resistance voltage division principle. The voltage transformer belongs to the field of power equipment and comprises a primary sensor, a converter and a closed shell, wherein a voltage divider formed by serially connecting a resistor and a capacitor is uses as the primary sensor; the capacitor consists of a low-voltage electrode and a high-voltage electrode in the closed shell; a central electrode mast or a tubular electrode is used as the low-voltage electrode; a tubular electrode surrounding the low-voltage electrode and concentric with the low-voltage electrode is used as the high-voltage electrode; a coaxial cylindrical capacitor is formed between the high-voltage electrode and the low-voltage electrode; the high-voltage electrode is connected with a lead led out of the shell; a middle-voltage electrode is connected with a lead led of the shell; and an integrator is used as the converter. The voltage transformer has the characteristics of being simple in structure and high in precision and being safe and reliable, and avoids the problem of ferromagnetic resonance of the traditional electromagnetic type voltage transformer.
Description
Technical field
The utility model belongs to the voltage measurement in the electrical equipment technical field, particularly relates to a kind of voltage transformer.
Background technology
Voltage transformer for power system is that the high-tension information of electrical network is delivered to metering, measuring instrument and the relaying protection of low-voltage secondary side, a kind of device of automatic control device; it is the contact element of primary system and electrical secondary system; its terminal inserts electrical network, and secondary output terminals interconnects with measuring instrument, protective device etc. respectively.Voltage transformer cooperates with measuring instrument and metering device, can measure the voltage and the electric energy of primary system; Cooperate with relaying protection and automatic control device, can constitute the electic protection of the various faults of electrical network and control automatically.The quality of voltage transformer performance directly has influence on the accuracy of power system measuring, metering and the reliability of protective relaying device action.
What generally use in the electric power system at present is traditional electromagnetic potential transformer and capacitance type potential transformer, and electromagnetic potential transformer is a kind of special transformer; Capacitance type potential transformer is a kind of improved form of electromagnetic potential transformer, and its principle is: press the back to introduce electromagnetic potential transformer during high pressure is got by capacitor voltage divider, obtain output signal from electromagnetic potential transformer again.There are following several problems in this voltage transformer of two types:
One, ferro resonance takes place easily, the harm electric power netting safe running.Because electromagnetic potential transformer is inductive element, easily with electrical network in other capacitive apparatus generation ferro resonance, generally can produce overvoltage during generation resonance, grid equipment is moved, the serious harm equipment safety operation under overvoltage.
Two, there is additive error in capacitance type potential transformer, and influence is measured and measuring accuracy.The oil immersion capacitance type potential transformer is formed by a plurality of capacitances in series, constitutes high-voltage capacitance C
1And middle piezoelectricity holds C
2Each capacity cell CY and all have stray capacitance on every side between special body size, the size of this stray capacitance is by each capacity cell and the distance between special body size and therebetween medium are determined on every side.When the position that instrument transformer is installed moving row changes, each capacity cell and on every side the distance between the special body size change, make the size of stray capacitance that corresponding variation also take place; When surrounding environment change or climate change, the dielectric coefficient of instrument transformer surrounding medium also can change, and causes stray capacitance to change.When changes in stray capacitances, the C of equivalence
1, C
2Must change, and then voltage ratio and middle pressure arm time constant change, and then the ratio of voltage transformer and angular difference also can and then change.The environment additive error of oil immersion capacitance type potential transformer commonly used will increase to some extent, and this will reduce instrument transformer greatly in the measurement of electric power system and the precision in the metering.
Three, dielectric loss is big, and the dielectric loss angle tangent of oil immersion capacitance type potential transformer is bigger, and about 1.2 * 10
-3About, will produce bigger electric energy loss during operation, and cause temperature to rise, unfavorable to the operation of instrument transformer.
Four, to the environment potential threat.Because the voltage divider and the calutron of electromagnetic potential transformer and capacitance type potential transformer all are immersed in the insulating oil, the seepage of oil pollutes the environment, in case puncture, insulating oil will be decomposed, and volume expands rapidly, produces the explosion of crunch housing.The insulating oil that overflows is lighted by the high temperature of electric shock generation after running into air, very easily causes fire.
Five, the transient performance of capacitance type potential transformer is poor.
Summary of the invention
The purpose of this utility model is for overcoming the weak point of prior art, a kind of voltage transformer based on the capacitance-resistance voltage divider principle is proposed, can be safe and reliable, accurately capacitance voltage is measured in real time, satisfy present electrical network intellectuality to requirements such as voltage transformer security reliability, transient performance and accuracys.
Voltage transformer based on the capacitance-resistance voltage divider principle of the present utility model is characterized in that, this voltage transformer comprises: primary transducer, transducer, and closed shell; Described primary transducer is the voltage divider that resistance and capacitances in series form; Described electric capacity is the low-field electrode that is arranged in the closed shell, and high-field electrode and lead constitute; This low-field electrode is the electrode column or the cylindrical electrode at center, and this high-field electrode is a cylindrical electrode, and this high-field electrode is looped around outside the low-field electrode, and concentric with low-field electrode; Form a concentric cylinder electric capacity between high-field electrode and the low-field electrode; This lead comprises the high-voltage conducting wires that connects high-field electrode and draw from housing one end; The primary cable that connects low-field electrode and draw from the housing other end; Described resistance is precision resistor; One end of described resistor is connected with low-field electrode by primary cable, and the other end of resistor is connected with the earth; The input of transducer is connected with low-field electrode by primary cable, and the output of transducer is an instrument transformer secondary output.
Compared with prior art: the utility model has following advantage:
One, do not have inductive element, not can with ferro resonance takes place;
Two, stray capacitance is very little, almost can ignore; Effectively solve the problem that capacitance type potential transformer stray capacitance commonly used increases error in dipping, improve measuring accuracy;
Three, adopt compressed gas insulation or vacuum insulation, make its dielectric loss tangent angle improve two more than the order of magnitude, so this instrument transformer energy consumption is little, temperature reduces greatly, has guaranteed reliability of operation.
Four, this instrument transformer does not have oil, has solved a series of problems such as a series of environmental pollutions that insulating oil brings, poor stability.
Five, transient performance is good.
Description of drawings
Fig. 1 is an example structure schematic diagram of the present utility model;
Fig. 2 is an operation principle block diagram of the present utility model;
Fig. 3 is the equivalent schematic diagram of the utility model embodiment;
Fig. 4 is the structure principle chart of analogue integrator among the utility model embodiment.
Embodiment
The utility model is further elaborated as follows below in conjunction with the embodiment accompanying drawing:
A kind of voltage transformer based on the capacitance-resistance voltage divider principle that the utility model proposes is characterized in that this voltage transformer comprises: primary transducer, transducer, and closed shell; Described primary transducer is the voltage divider that resistance and capacitances in series form; Described electric capacity is low-field electrode, the high-field electrode that is arranged in the closed shell, and the lead of connection electrode constitutes; This low-field electrode is the electrode column or the cylindrical electrode at center, and this high-field electrode is a cylindrical electrode, and this high-field electrode is looped around outside the low-field electrode, and concentric with low-field electrode; Form a concentric cylinder electric capacity between high-field electrode and the low-field electrode; This lead comprises the high-voltage conducting wires that connects high-field electrode and draw from housing one end; The primary cable that connects low-field electrode and draw from the housing other end; Described resistance is precision resistor; One end of described resistor is connected with low-field electrode by primary cable, and the other end of resistor is connected with the earth; The input of transducer is connected with low-field electrode by primary cable, and the output of transducer is an instrument transformer secondary output.
The closed at both ends of above-mentioned low-field electrode cylindrical electrode, the end sealing of this high-field electrode cylindrical electrode.
Above-mentioned instrument transformer also comprises base, and described seal casinghousing is fixed by ring flange and disc insulator, fixes by ring flange and disc insulator and base; Described precision resistor is fixed in the interior cavity of base.
Above-mentioned primary transducer enclosure interior can charge into the dielectric that insulation property are good and dielectric coefficient is stable or be pumped into high vacuum; Described dielectric media can be solid, liquid or gas.
Above-mentioned transducer is an integrator but is not limited to digital integration or analogue integrator.
Operation principle of the present utility model:
High pressure cylinder in hermetically sealed can is nested with low pressure cylinder (coupling tube), constitutes the concentric cylinder capacitor; One end of sampling resistor is connected with the coupling tube, and the another port links to each other with the earth, and then described ganged condenser and sampling resistor constitute equivalent electric circuit as shown in Figure 2.Because the medium dielectric constant is stable in the hermetically sealed can, so this is stable as long as mechanical structure keeps, ganged condenser capacity will be highly stable.
As shown in Figure 2, capacitor C connects with resistor R, constitutes the capacitance-resistance bleeder circuit.Wherein, U
1Be the input voltage of voltage transformer, U
0Be the output voltage of primary transducer, U
2Output voltage for voltage transformer; U
0With U
1Following relation is arranged:
When the capacitive reactance Xc of C＞＞during R, U
0＜＜U1, Uc=U at this moment
1-U
0≈ U
1, then have:
Formula 2 explanations, output voltage U
0(t) approx with input voltage U
1(t) become differential relationship; As long as obtaining U
0(t) after again to U
0(t) carry out integration, just can obtain and U
1(t) voltage signal of proportional relation.If being A, storage gain then has:
By formula 3 as can be known, the precision of integration depends on the precision of resistance R and capacitor C.In implementation process, the required precision of resistance R becomes more readily available satisfied, and the ratio of precision of capacitor C is difficult to guarantee; Moreover, because the general value of capacitor C is less, be subjected to the influence of stray capacitance easily.For addressing these problems, in the utility model, having done on dielectric material and structure significantly of capacitor C optimized, and its electric capacity stability is improved significantly: its medium adopts substantially invariable Compressed Gas of dielectric coefficient or vacuum; Structurally, adopting with the low-field electrode is that the concentric cylinder capacitor that center, high-field electrode are overlapping low-field electrode has guaranteed the stability of capacitor mechanical structure effectively and reduced low-field electrode stray capacitance over the ground.
This capacitance-resistance branch pressure voltage instrument transformer example structure as shown in Figure 1, this voltage transformer comprises: primary transducer, transducer, and closed shell 2 and base 10; Described primary transducer is the voltage divider that resistance and capacitances in series form; Described electric capacity is that the low-field electrode 4 and the high-field electrode 3 that are arranged in the closed shell 2 constitute; Low-field electrode 4 is the electrode column at center or the cylindrical electrode of closed at both ends, and high-field electrode 3 is the cylindrical electrode of end sealing, and this high-field electrode is looped around outside the low-field electrode, and concentric with low-field electrode; Form a concentric cylinder electric capacity between high-field electrode 3 and the low-field electrode 4; Described seal casinghousing 2 is fixing with disc insulator 9 by ring flange 11, and is fixing with disc insulator 12 and base 10 by ring flange 13; This lead comprises the high-voltage conducting wires 1 that connects high-field electrode and draw from housing one end; The primary cable 5 that connects low-field electrode and draw from the housing other end; Described resistance 6 is precision resistor; Described resistor 6 is fixed in the cavity in the base 10; One end of described resistor 6 is connected with low-field electrode 4 by primary cable, and the other end of resistor is connected with the earth; Described transducer 7 is an integrator, and the input of transducer is connected with low-field electrode 4 by primary cable, and the output of transducer is an instrument transformer secondary output.
It is SF that closed shell 2 inside of present embodiment charge into the good dielectric of insulation property
6Gas or vacuum.
The equivalent operation principle of this embodiment as shown in Figure 3.High-field electrode 3 constitutes capacitor C with low-field electrode 4, and high-field electrode 3 constitutes stray capacitance C ' with the earth; Because C ' is the high pressure direct-to-ground capacitance, it is to U
0Not influence.In sum, U in the circuit shown in Figure 3
1With signal output U
2Relation identical with Fig. 2:
If k=ARC, substitution formula 3:
Each functions of components of present embodiment and embodiment are described in detail as follows:
Described seal casinghousing 2 is a box hat.
Described high-field electrode 3 can be the one aluminium casting with high-voltage conducting wires 1, through after the meticulous polishing, is compressed to one with disc insulator 9.
Described low-field electrode 4 can be the one aluminium casting with primary cable 5, through after the meticulous polishing, is compressed to one with disc insulator 12.
Charged pressure is the SF6 gas of 4 standard atmospheric pressures in the described seal casinghousing 2.
Described resistance 6 is the accurate four-terminal resistance of 1 watt of 10 ohm of power of resistance.
Described base 10 is the steel foundry goods.
Described transducer is an analogue integrator, transducer can with the integrated assembling of primary transducer, also can be installed separately with primary transducer.
The structure of the integrator that present embodiment adopts as shown in Figure 4, this integrator is made up of amplifier, resistance and capacitor C; Amplifier is selected the OPA177 with FET input stage for use, and resistance R is selected the 3.3K precision resistance for use, and capacitor C is selected the accurate CB capacitor of 1uF for use.If input voltage is U
1(t), output voltage is U
0(t), then input voltage and output voltage have following relation:
Be U
0(t) be U
1(t) to the integration of time.
Claims (5)
1. the voltage transformer based on the capacitance-resistance voltage divider principle is characterized in that, this voltage transformer comprises: primary transducer, transducer, and closed shell; Described primary transducer is the voltage divider that resistance and capacitances in series form; Described electric capacity is low-field electrode, the high-field electrode that is arranged in the closed shell, and the lead of connection electrode constitutes; This low-field electrode is the electrode column or the cylindrical electrode at center, and this high-field electrode is a cylindrical electrode, and this high-field electrode is looped around outside the low-field electrode, and concentric with low-field electrode; Form a concentric cylinder electric capacity between high-field electrode and the low-field electrode; This lead comprises the high-voltage conducting wires that connects high-field electrode and draw from housing one end; The primary cable that connects low-field electrode and draw from the housing other end; Described resistance is precision resistor; One end of described resistor is connected with low-field electrode by primary cable, and the other end of resistor is connected with the earth; The input of transducer is connected with low-field electrode by primary cable, and the output of transducer is an instrument transformer secondary output.
2. voltage transformer according to claim 1 is characterized in that, the closed at both ends of described low-field electrode cylindrical electrode, the end sealing of this high-field electrode cylindrical electrode.
3. voltage transformer according to claim 1 is characterized in that also comprise base, described seal casinghousing is fixed by ring flange and disc insulator, fixes by ring flange and disc insulator and base; Described precision resistor is fixed in the interior cavity of base.
4. voltage transformer according to claim 1 is characterized in that described primary transducer enclosure interior charges into the dielectric that insulation property are good and dielectric coefficient is stable or is pumped into high vacuum; Described dielectric media is solid, liquid or gas.
5. as voltage transformer as described in the claim 1,2,3 or 4, it is characterized in that described transducer is an integrator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010205715652U CN201853571U (en) | 2010-10-22 | 2010-10-22 | Voltage transformer based on capacitance-resistance voltage division principle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010205715652U CN201853571U (en) | 2010-10-22 | 2010-10-22 | Voltage transformer based on capacitance-resistance voltage division principle |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201853571U true CN201853571U (en) | 2011-06-01 |
Family
ID=44095957
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010205715652U Expired - Fee Related CN201853571U (en) | 2010-10-22 | 2010-10-22 | Voltage transformer based on capacitance-resistance voltage division principle |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201853571U (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102005289A (en) * | 2010-10-22 | 2011-04-06 | 北京浩霆光电技术有限责任公司 | Resistor-capacitor voltage division principle-based voltage transformer |
| CN103187159A (en) * | 2011-12-29 | 2013-07-03 | 大连第一互感器有限责任公司 | Gas-sealing and resistance-dividing voltage sensor |
| CN103869152A (en) * | 2014-03-07 | 2014-06-18 | 西安交通大学 | Low-inductance resistor-capacitor element |
| CN104764919A (en) * | 2015-03-16 | 2015-07-08 | 中国计量学院 | Electronic type voltage transformer based on lossy double integrating circuit |
| CN107942115A (en) * | 2017-10-22 | 2018-04-20 | 国网山西省电力公司电力科学研究院 | The capacitance partial pressure type high voltage meter of adjustable intrinsic standoff ratio |
| AT521182A4 (en) * | 2018-07-11 | 2019-11-15 | Greenwood Power Og | Voltage dividing device with rod structure |
-
2010
- 2010-10-22 CN CN2010205715652U patent/CN201853571U/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102005289A (en) * | 2010-10-22 | 2011-04-06 | 北京浩霆光电技术有限责任公司 | Resistor-capacitor voltage division principle-based voltage transformer |
| CN103187159A (en) * | 2011-12-29 | 2013-07-03 | 大连第一互感器有限责任公司 | Gas-sealing and resistance-dividing voltage sensor |
| CN103869152A (en) * | 2014-03-07 | 2014-06-18 | 西安交通大学 | Low-inductance resistor-capacitor element |
| CN103869152B (en) * | 2014-03-07 | 2016-04-27 | 西安交通大学 | A kind of low inductance Resistor-Capacitor Unit |
| CN104764919A (en) * | 2015-03-16 | 2015-07-08 | 中国计量学院 | Electronic type voltage transformer based on lossy double integrating circuit |
| CN104764919B (en) * | 2015-03-16 | 2017-12-22 | 中国计量学院 | Based on the electronic type voltage transformer for damaging double integrating circuit |
| CN107942115A (en) * | 2017-10-22 | 2018-04-20 | 国网山西省电力公司电力科学研究院 | The capacitance partial pressure type high voltage meter of adjustable intrinsic standoff ratio |
| CN107942115B (en) * | 2017-10-22 | 2019-12-13 | 国网山西省电力公司电力科学研究院 | Capacitance voltage-dividing type high-voltage measuring device capable of adjusting voltage-dividing ratio |
| AT521182A4 (en) * | 2018-07-11 | 2019-11-15 | Greenwood Power Og | Voltage dividing device with rod structure |
| AT521182B1 (en) * | 2018-07-11 | 2019-11-15 | Greenwood Power Og | Voltage dividing device with rod structure |
| US11456118B2 (en) | 2018-07-11 | 2022-09-27 | Greenwood-Power GmbH | Voltage division device having a rod-like structure |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201853571U (en) | Voltage transformer based on capacitance-resistance voltage division principle | |
| CN102005289B (en) | Resistor-capacitor voltage division principle-based voltage transformer | |
| CN101256892B (en) | Novel high voltage independent type electronic voltage mutual inductor | |
| CN201812667U (en) | Electronic current and voltage combined transformer | |
| CN102608388B (en) | VFTO (very fast transient overvoltage) measurement method and system | |
| CN201285439Y (en) | Integrated verification equipment for field CVT | |
| CN102737828B (en) | With the capacitance type potential transformer of transient over-voltage monitoring unit | |
| CN201812668U (en) | Electronic type current and voltage combined mutual inductor of three-phase enclosed GIS (Geographic Information System) | |
| CN103630803B (en) | A kind of cable partial discharge live correction method | |
| CN101738591A (en) | On-site CVT integrated verification system | |
| CN103575951A (en) | Coupling capacitive voltage divider with electric potential gradient shielding | |
| CN203572859U (en) | Novel high-voltage impact resistor voltage divider device | |
| CN106645859A (en) | Capacitive voltage divider | |
| CN201096820Y (en) | Fully shielding capacitance voltage mutual inductor | |
| CN201259830Y (en) | Electronic voltage mutual inductor | |
| CN201134349Y (en) | Novel high-voltage combined independent electronic current, voltage mutual inductor | |
| CN110320395A (en) | On-line monitoring high-precision capacitance-resistance parallel voltage divider | |
| CN102043082A (en) | Conical capacitive transducer | |
| CN104977449A (en) | Optical voltage transformer based on SF6 coaxial capacitance voltage divider | |
| CN101201366A (en) | Whole shielding capacitor voltage transformer | |
| CN110542777B (en) | Three-phase integrated GIS independent bus voltage measuring device | |
| CN203324357U (en) | Electronic voltage transformer used for detecting high voltage resistor current | |
| CN207516494U (en) | A kind of bus voltage measurement device based on GIS disc insulator distribution capacity | |
| CN110031789A (en) | The gamut caliberating device and scaling method of high-voltage nanosecond pulse divider scale factor | |
| CN201716359U (en) | Non-contact electronic type voltage sampling device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110601 Termination date: 20111022 |