CN201134346Y - Novel high-voltage independent electronic voltage mutual inductor - Google Patents
Novel high-voltage independent electronic voltage mutual inductor Download PDFInfo
- Publication number
- CN201134346Y CN201134346Y CNU2007203005290U CN200720300529U CN201134346Y CN 201134346 Y CN201134346 Y CN 201134346Y CN U2007203005290 U CNU2007203005290 U CN U2007203005290U CN 200720300529 U CN200720300529 U CN 200720300529U CN 201134346 Y CN201134346 Y CN 201134346Y
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Abstract
The utility model relates to a novel high voltage detached potential transformer, which comprises an inverted SF6 gas insulted current transformer without a secondary winding, an electronic potential transformer, a signal conditioning and modulating circuit and a direct current power supply, wherein a low voltage electrode is fixed on the internal layer of a double-layer shielding barrel and insulated form the internal layer of the double-layer shielding barrel, the low voltage electrode, a primary conductor and the double-layer shielding barrel internal layer are concentric, the low voltage electrode and the internal layer of the double-layer shielding barrel are respectively welded or fixed with a wire as a secondary sensing output wire of the potential transformer, the current secondary winding output wire is connected with a signal input end of the signal conditioning and modulating circuit, and the direct current power supply is connected with a power input end of the signal conditioning and modulating circuit. The novel high voltage detached electronic potential transformer utilizes SF6 as the main insulator which has simple structure and high insulation intensity, thereby completely overcoming the weaknesses of the electronic potential transformers and significantly reducing cost.
Description
Technical field
The utility model relates to a kind of novel high voltage independent type electronic voltage mutual inductor, is used for the voltage transformation under the open type transformer station high voltage environment, and for measuring, protect and the monitoring use, this invention is applicable to 110kV and above high-voltage electric power system.
Background technology
Present free-standing capacitance partial pressure electronic type voltage transformer generally is the multistage capacitances in series dividing potential drop mode that adopts the voltage transformer (being called for short CVT) that is similar to capacitance-voltage-distributing type, the high voltage branch is depressed into than behind the electronegative potential, be transformed into digital light pulse again and carry out the signal transmission, this method does not need the light power supply.But this structure is big because of the coupling capacitor temperature coefficient, can reach 5 * 10-5/k, be subjected to the external environment factor: be bigger as influences such as high-voltage connection, filth, humidity, though for example CVT has adopted the method that increases the dividing potential drop capacitance to reduce the influence of extraneous space stray capacitance to the voltage voltage ratio as far as possible, but the practice of operation for many years shows that the voltage ratio of CVT takes place to drift about and remains comparatively general phenomenon in long-term actual motion.
The subject matter of high voltage independent type electronic voltage mutual inductor is at present: independent type electronic voltage mutual inductor adopts the multistage capacitances in series dividing potential drop mode of similar CVT, be subject to the influence that distributed capacitance that the external environment factor causes changes, certainty of measurement is low, poor stability.
Summary of the invention
The utility model provides a kind of novel independent type electronic voltage mutual inductor, overcomes the defective of above-mentioned electronic type voltage transformer fully, utilizes inverted SF
6The ground electrode that the double layer screen tube of the Primary Conductor of gas insulated high voltage current transformer and internal layer, outer electrical communication constitutes, construct coaxial cylindrical capacitor dividing potential drop dexterously, overcome the shortcoming that multistage capacitances in series dividing potential drop mode is subject to the distributed capacitance variable effect that the external environment factor causes, the certainty of measurement height, good stability; The utility model utilizes inverted gas insulated high voltage current transformer insulation system to constitute independent type electronic voltage mutual inductor on the basis of the above once more dexterously.
Novel independent type electronic voltage mutual inductor comprises an inverted SF who does not have the secondary current winding
6Gas insulated high voltage current transformer, the electronic type voltage transformer, signal condition modulation circuit and the DC power supply that adopt coaxial cylindrical capacitance partial pressure principle to constitute is characterized in that: at inverted SF
6Fixing metal column ring on the inner surface of the double layer screen tube internal layer of gas insulated high voltage current transformer, the columnar metal ring by insulating material on electric with the inner surface insulation of double layer screen tube internal layer, and columnar metal ring and Primary Conductor and double layer screen tube are concentric and constitute the electronic type voltage transformer of coaxial cylindrical capacitor voltage divider principle, Primary Conductor is a high-field electrode, the columnar metal ring is a low-field electrode, the double layer screen tube is a ground electrode, welding or holding electrical are connected a lead and export as the voltage transformer secondary sensing respectively on low-field electrode and double layer screen tube internal layer, the lead of voltage transformer secondary sensing output is connected with the signal input part of signal condition modulation circuit, and DC power supply links to each other with the power input of signal condition modulation circuit.
Novel independent type electronic voltage mutual inductor described in the utility model, comprise the insulation system of an inverted SF6 gas insulated high voltage current transformer that does not have a secondary current winding and utilize same insulation system, the electronic type voltage transformer that adopts coaxial cylindrical capacitance partial pressure principle to constitute, be positioned at earthy signal condition modulation circuit and DC power supply, concrete parts comprise housing, insulating sleeve, the lead-in wire shielded-plate tube, supporting insulator or disc insulator, Primary Conductor, low-field electrode, the double layer screen tube of ground electrode, rupture disk, the secondary sensing output wiring terminal of the voltage transformer on base and the base, SF
6Gas density controller, SF
6Inflation inlet and pipeline valve, signal condition modulation circuit, DC power supply is characterized in that:
1, this independent type electronic voltage mutual inductor comprises: at inverted SF
6Fixing metal column ring on the inner surface of the double layer screen tube internal layer of gas insulated high voltage current transformer, this columnar metal ring by insulating material on electric with the inner surface insulation of double layer screen tube internal layer, and columnar metal ring and Primary Conductor and double layer screen tube are concentric and constitute the electronic type voltage transformer of coaxial cylindrical capacitor voltage divider principle, Primary Conductor is a high-field electrode, the columnar metal ring is a low-field electrode, the double layer screen tube is a ground electrode, welding or holding electrical are connected a lead and export as the voltage transformer secondary sensing respectively on low-field electrode and double layer screen tube internal layer, the lead of voltage transformer secondary sensing output is connected with the signal input part of signal condition modulation circuit, and DC power supply links to each other with the power input of signal condition modulation circuit.High-field electrode and low-field electrode all are positioned at the shield that ground connection double layer screen tube constitutes, and this special double shield structure can reduce the influence of extraneous distributed capacitance and stray capacitance greatly.Electric capacity between the low-field electrode of Primary Conductor and structure constitutes high-voltage capacitance, just the electric capacity between the ground electrode is as sampling capacitor for the inner surface of low-field electrode and double layer screen tube internal layer, and the signal of telecommunication on it is the output of secondary sensing or the sampled signal of this voltage transformer.
2, the voltage transformer of this independent type electronic voltage mutual inductor utilizes inverted SF
6The insulation system of gas insulated high voltage current transformer.
3, the secondary singal output of the voltage sensor of this independent type electronic voltage mutual inductor part is transmitted in the lead-in wire shielded-plate tube of a ground connection, can reduce the influence of outside electromagnetic interference to transmission line greatly.
4, this independent type electronic voltage mutual inductor also comprises and is positioned at earthy signal condition modulation circuit and DC power supply, and DC power supply is directly given the power supply of signal condition modulation circuit with cable.
5, the secondary singal of this independent type electronic voltage mutual inductor exports the signal condition modulation circuit to, this circuit is arranged in earth potential double layer screen tube, after signal transformation become digital optical signal, with transferring to the optical fiber connector that are fixed on the base downwards in the ground lead shielded-plate tube of optical fiber from insulated porcelain sleeve or synthetic insulator cover, this optical signal transmission maybe can be needed this voltage signal place to the control room with optical fiber or optical cable then.At this moment, the dc supply of this signal condition modulation circuit also is arranged in earth potential double layer screen tube, and available cable will exchange or DC power supply transfers to the earth potential shielding cylinder from base by the ground lead shielded-plate tube insulated porcelain sleeve or the synthetic insulator cover.
6, the output of the secondary singal of this independent type electronic voltage mutual inductor also can be without conversion, directly with transferring to the secondary electric connecting terminals that is fixed on the base downwards in the ground lead shielded-plate tube of cable from insulated porcelain sleeve or synthetic insulator cover, again by the electric connecting terminals input signal conditioning modulation circuit on the base, at this moment, signal condition modulation circuit and dc supply all are positioned at SF
6Outside the air seal, be more conducive to the maintenance and the maintenance of dc supply, signal condition modulation circuit.
Voltage transformer transducing part principle of the present utility model, see accompanying drawing 2: at the coaxial capacitance structure of structure, according to the principle of cylindrical capacitor:
Suppose that the voltage on the high-field electrode is u, the diameter of high-field electrode is d, and the signal of interlayer is u in low-field electrode and the double layer screen tube
o, the diameter of low tension polar ring is D, and the ring height is b, and the electric capacity between high-field electrode and low-field electrode is C1, and the electric capacity between the inner surface of low-field electrode and double layer screen tube internal layer is C2.
Wherein:
Consider that the electric charge that gathers on the ground capacity of column electric capacity ring behind the system short-circuit does not discharge if also have fully when reclosing; an error component will superpose on system works voltage; to have influence on the correctness of measurement result and the correct operation of protective relaying device when serious; therefore it is in parallel with C2 to choose a small resistor R; to eliminate the influence of these factors; R＜＜1/ (ω C2), ω is the frequency of tested alternating voltage.Wherein the signal between low-field electrode and the double layer screen tube internal layer is:
As seen, the transducing signal of voltage transformer of the present utility model output u
oBe directly proportional with the time-derivative of tested voltage u on the high-field electrode, therefore adopt the signal condition modulation circuit u
oCarry out the analog or digital integration and can obtain u
oValue.
The function of signal condition modulation circuit is: the signal input part that voltage transformer secondary sensing output signal of the present utility model is input to the signal condition modulation circuit, again this voltage signal integration is amplified reduction, then through becoming the digital light pulse signal after mould/transformation of variables and the light-to-current inversion, so that transfer to the follow up device place with optical fiber.
Particularly, the utlity model has following technique effect:
Novel independent type electronic voltage mutual inductor described in the utility model utilizes an inverted SF who does not have the secondary current winding
6The ground electrode that the double layer screen tube of the high-pressure conductor of gas insulated high voltage current transformer and internal layer, outer electrical communication constitutes, construct coaxial cylindrical capacitor dividing potential drop dexterously, compare with general electronic type voltage transformer, overcome the shortcoming that multistage capacitances in series dividing potential drop mode is subject to the distributed capacitance variable effect that the external environment factor causes, the certainty of measurement height, good stability; Compare with the conventional voltage instrument transformer, sensing principle is different fully, does not contain iron core, does not have the threat of resonance overvoltage.
Description of drawings
Fig. 1 a is the general structure schematic diagram of novel independent type electronic voltage mutual inductor of the present utility model.
Fig. 1 b is another general structure schematic diagram of novel independent type electronic voltage mutual inductor of the present utility model.
Fig. 2 is a voltage transformer transducing part schematic diagram of the present utility model.
Embodiment
General structure of the present utility model has been utilized the insulation system of inverted gas insulated high voltage current transformer as shown in Figure 1a.Double layer screen tube internal layer 1 and double layer screen tube outer 2 constitutes earth potential double layer screen tube 4, and be fixed on the housing 6 through supporting insulator 5, Primary Conductor 7 is flatly traversed double layer screen layer inboard and is fixed on the housing 6, Primary Conductor 7 left ends and housing 6 are electrically connected, right-hand member insulate with housing 6 on electric through sealing ring and insulating case 8, the top of housing 6 also is equipped with rupture disk 3, can be used for discharging too high SF
6Air pressure, protection housing 6 and insulating sleeve 13; Be fixed on the inner surface of double layer screen tube internal layer 1 columnar metal ring 9 by insulating material 10 on electric with the inner surface insulation of double layer screen tube internal layer 1, and this columnar metal ring 9 is concentric with Primary Conductor 7 and double layer screen tube 4, this columnar metal ring 9 is a low-field electrode, weld out a lead (11,12) on low-field electrode 9 and double layer screen tube internal layer 1 respectively, these two leads (11,12) are formed voltage transformer secondary sensing output sampled signal and ground electrode line; Primary Conductor 7, double layer screen tube internal layer 1, double layer screen tube skin 2, columnar metal ring 9 and housing 6 constitute this instrument transformer device body and place insulating sleeve 13 tops, and 13 of insulating sleeves are loaded on the base 14; Voltage transformer secondary sensing output lead and ground electrode line (11,12) are drawn through base 14 and the secondary terminal sealed wiring dish 16 from base 14 down from lead-in wire shielded-plate tube 17; Double layer screen tube internal layer 1, double layer screen tube outer 2 and lead-in wire shielded-plate tube 17 all are electrically connected by lead and the earth that passes lead-in wire shielded-plate tube 17 simultaneously.Be filled with SF in this structure of the present utility model
6Gas 18,9 of Primary Conductor 7 and low-field electrodes are SF
6Gas-insulated.6 of the housings of double layer screen tube 4 and high potential are the supporting insulator 5 of poured with epoxy resin solid insulation, also can use disc insulator.Also be provided with SF on the base 14
6 Gas density controller 19, SF
6 Inflation inlet 20 and pipeline valve 21 etc. are used for inflation and monitor SF
6Gas density is used.
Signal condition modulation circuit 22 adopts electronic type voltage transformer signal condition modulation circuit commonly used on the existing market.DC power supply 23 is also bought from the market.
Signal condition modulation circuit 22 and DC power supply 23 all are positioned at SF among Fig. 1 a
6In the earth shield box 24 outside the air seal;
Signal condition modulation circuit 22 and DC power supply 23 are arranged in double shield layer internal layer 1 and the outer 2 earth potential shielding cylinders 4 that constitute among Fig. 1 b.
The output of the secondary singal of voltage transformer of the present utility model is directly with transferring to the electric wiring terminal that is fixed on the base 14 downwards in the ground lead shielded-plate tube 17 of cable from insulated porcelain sleeve 13 or synthetic insulator cover among Fig. 1 a, again by the electric wiring terminal input signal conditioning modulation circuit 22 on the base 14, at this moment, this signal condition modulation circuit 22 and DC power supply 23 all are positioned at SF
6In the earth shield box 24 outside the air seal, this shielding box can be fixed on the base outer wall, is more conducive to the maintenance and the maintenance of DC power supply 23, signal condition modulation circuit 22.The input of the power supply of DC power supply 23 can be and exchanges or the direct current input, by cable 15 from the control room or the scene supply with on the spot.
The secondary transducing signal of voltage transformer of the present utility model exports the signal condition modulation circuit 22 of electronic mutual inductor among Fig. 1 b, this circuit is arranged in the earth potential shielding cylinder 4 of double layer screen tube internal layer 1, outer 2 formations of double layer screen tube, after this circuit becomes digital optical signal with signal transformation, with transferring to the optical fiber connector 26 that are fixed on the base 14 downwards in the ground lead shielded-plate tube 17 of optical fiber 25 from insulated porcelain sleeve 13 or synthetic insulator cover, this optical signal transmission maybe can be needed this voltage signal place to the control room with optical fiber 25 or optical cable then.At this moment, the DC power supply 23 of this signal condition modulation circuit 22 also is arranged in earth potential shielding cylinder 4, and available cable 15 transfers to the DC power supply 23 required ground lead shielded-plate tubes 17 of electrical power from base 14 overlaps by insulated porcelain sleeve 13 or synthetic insulator the input of the DC power supply 23 in the earth potential shielding cylinder 4.Advantage is that the signal antijamming capability is very strong.
Claims (4)
1, novel high voltage independent type electronic voltage mutual inductor comprises an inverted SF who does not have the secondary current winding
6Gas insulated high voltage current transformer, the electronic type voltage transformer, signal condition modulation circuit and the DC power supply that adopt coaxial cylindrical capacitance partial pressure principle to constitute is characterized in that: at inverted SF
6Fixing metal column ring on the inner surface of the double layer screen tube internal layer of gas insulated high voltage current transformer, the columnar metal ring by insulating material on electric with the inner surface insulation of double layer screen tube internal layer, and columnar metal ring and Primary Conductor and double layer screen tube are concentric and constitute the electronic type voltage transformer of coaxial cylindrical capacitor voltage divider principle, Primary Conductor is a high-field electrode, the columnar metal ring is a low-field electrode, the double layer screen tube is a ground electrode, welding or holding electrical are connected a lead and export as the voltage transformer secondary sensing respectively on low-field electrode and double layer screen tube internal layer, the lead of voltage transformer secondary sensing output is connected with the signal input part of signal condition modulation circuit, and DC power supply links to each other with the power input of signal condition modulation circuit.
2, novel high voltage independent type electronic voltage mutual inductor according to claim 1 is characterized in that: adopt inverted SF
6The gas insulated high voltage current transformer insulation system, double layer screen tube internal layer and outer formation earth potential shielding cylinder, the earth potential shielding cylinder is fixed on the housing through supporting insulator or disc insulator, the Primary Conductor level is traversed the double layer screen tube and is fixed on the housing, Primary Conductor one end and housing are electrically connected, the other end insulate with housing on electric through sealing ring and insulating case, the top of housing also is equipped with rupture disk, be fixed on the inner surface of double layer screen tube internal layer the columnar metal ring by insulating material on electric with the inner surface insulation of double layer screen tube internal layer, and the columnar metal ring is concentric with Primary Conductor and double layer screen tube, Primary Conductor is a high-field electrode, the columnar metal ring is a low-field electrode, the double layer screen tube is a ground electrode, welding out a lead respectively on low-field electrode and double layer screen tube internal layer exports as the voltage transformer secondary sensing, Primary Conductor, double layer screen tube internal layer, double layer screen tube skin, low-field electrode and housing constitute instrument transformer device body and place the insulating sleeve top, the insulating case base is loaded on the base, the lead of voltage transformer secondary sensing output is drawn with the signal input part of signal condition modulation circuit through base and the secondary terminal sealed wiring dish from the base down from the lead-in wire shielded-plate tube and is connected, DC power supply links to each other with the power end of signal condition modulation circuit, double layer screen tube internal layer, double layer screen tube skin and lead-in wire shielded-plate tube all are electrically connected by lead and the earth, and signal condition modulation circuit and DC power supply are installed on SF
6In the earth shield box outside the air seal.
3, novel high voltage independent type electronic voltage mutual inductor according to claim 2, it is characterized in that: the lead of voltage transformer secondary sensing output is connected with the signal input part of signal condition modulation circuit, DC power supply links to each other with the power input of signal condition modulation circuit, signal condition modulation circuit and DC power supply are installed on the earth potential shielding cylinder, the output of signal condition modulation circuit are drawn through base and the secondary terminal sealed wiring dish from base down from the lead-in wire shielded-plate tube by optical fiber again.
4, novel high voltage independent type electronic voltage mutual inductor according to claim 1 and 2 is characterized in that: be SF between Primary Conductor and secondary winding and low-field electrode
6Gas-insulated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007203005290U CN201134346Y (en) | 2007-12-29 | 2007-12-29 | Novel high-voltage independent electronic voltage mutual inductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007203005290U CN201134346Y (en) | 2007-12-29 | 2007-12-29 | Novel high-voltage independent electronic voltage mutual inductor |
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| Publication Number | Publication Date |
|---|---|
| CN201134346Y true CN201134346Y (en) | 2008-10-15 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2007203005290U Expired - Lifetime CN201134346Y (en) | 2007-12-29 | 2007-12-29 | Novel high-voltage independent electronic voltage mutual inductor |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101901679B (en) * | 2009-05-26 | 2012-04-25 | 西安华伟光电技术有限公司 | Concentricity-autocompensation type coaxial capacitance partial pressure electronic voltage transformer and compensation method thereof |
| CN102479606A (en) * | 2010-11-27 | 2012-05-30 | 江苏思源赫兹互感器有限公司 | Dividing type electronic voltage transformer of three-phase capacitor |
| CN102479607A (en) * | 2010-11-27 | 2012-05-30 | 江苏思源赫兹互感器有限公司 | Dividing type electronic voltage transformer of single-phase capacitor |
| CN102024557B (en) * | 2009-09-21 | 2015-09-16 | 江苏思源赫兹互感器有限公司 | Electronic current mutual inductor |
| CN105467187A (en) * | 2015-12-04 | 2016-04-06 | 国家电网公司 | A graded type voltage transformer |
| CN107464679A (en) * | 2017-09-15 | 2017-12-12 | 苏州正罡互感器有限公司 | A kind of voltage transformer by the use of fluorinated mixed gas as dielectric |
| CN108291928A (en) * | 2015-11-24 | 2018-07-17 | 菲尼克斯电气公司 | Induction type current mutual inductor |
| CN109346302A (en) * | 2018-12-03 | 2019-02-15 | 大连北方互感器集团有限公司 | A kind of voltage transformer shielded with high-tension shielding and low pressure |
-
2007
- 2007-12-29 CN CNU2007203005290U patent/CN201134346Y/en not_active Expired - Lifetime
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101901679B (en) * | 2009-05-26 | 2012-04-25 | 西安华伟光电技术有限公司 | Concentricity-autocompensation type coaxial capacitance partial pressure electronic voltage transformer and compensation method thereof |
| CN102024557B (en) * | 2009-09-21 | 2015-09-16 | 江苏思源赫兹互感器有限公司 | Electronic current mutual inductor |
| CN102479606A (en) * | 2010-11-27 | 2012-05-30 | 江苏思源赫兹互感器有限公司 | Dividing type electronic voltage transformer of three-phase capacitor |
| CN102479607A (en) * | 2010-11-27 | 2012-05-30 | 江苏思源赫兹互感器有限公司 | Dividing type electronic voltage transformer of single-phase capacitor |
| CN108291928A (en) * | 2015-11-24 | 2018-07-17 | 菲尼克斯电气公司 | Induction type current mutual inductor |
| CN108291928B (en) * | 2015-11-24 | 2021-09-10 | 菲尼克斯电气公司 | Induction type current transformer |
| CN105467187A (en) * | 2015-12-04 | 2016-04-06 | 国家电网公司 | A graded type voltage transformer |
| CN105467187B (en) * | 2015-12-04 | 2018-05-22 | 国家电网公司 | A kind of stagewise voltage transformer |
| CN107464679A (en) * | 2017-09-15 | 2017-12-12 | 苏州正罡互感器有限公司 | A kind of voltage transformer by the use of fluorinated mixed gas as dielectric |
| CN109346302A (en) * | 2018-12-03 | 2019-02-15 | 大连北方互感器集团有限公司 | A kind of voltage transformer shielded with high-tension shielding and low pressure |
| CN109346302B (en) * | 2018-12-03 | 2023-08-08 | 大连北方互感器集团有限公司 | Voltage transformer with high-voltage shielding and low-voltage shielding |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20081015 Effective date of abandoning: 20071229 |