CN207301251U - Transformer insulated property detection device - Google Patents
Transformer insulated property detection device Download PDFInfo
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- CN207301251U CN207301251U CN201721345544.7U CN201721345544U CN207301251U CN 207301251 U CN207301251 U CN 207301251U CN 201721345544 U CN201721345544 U CN 201721345544U CN 207301251 U CN207301251 U CN 207301251U
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- overvoltage
- current detection
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Abstract
The utility model discloses transformer insulated property detection device, the corresponding current detection circuit of installation at the Transformer Bushing Tap extraction line interface of different structure size, the position of bushing shell for transformer root or inconvenience installation fixed dimension sensor, ultra-high frequency antenna, gather the shelf depreciation electric current of transformer, overvoltage electric current, power frequency leakage current, without the shelf depreciation electric current and ultra-high frequency antenna electric current at the Folding-Screen ground wires of casing end, the insulating properties of transformer is checked comprehensively, improves the accuracy that insulating properties judges；At neutral ground line, the powered current detection circuit of installing broad-band at iron core grounding line interface, the shelf depreciation of transformer is detected at iron core grounding line, judges to provide data basis for insulating properties, helps to further improve the accuracy that insulating properties judges.
Description
Technical field
It the utility model is related to transformer performance detection technique, and in particular to transformer insulated property detection device.
Background technology
Transformer is the device for changing alternating voltage using the principle of electromagnetic induction, and main member is primary coil, secondary
Level coil and iron core, are mainly used for voltage transformation, current transformation, impedance conversion, isolation, voltage stabilizing etc..With China's national grid
The constantly improve of system and the continuous enlarging of electric system, number transformer increase considerably, the insulating properties of transformer can
Have by property on the safety of power grid and directly restrict and influence.
Therefore, in use, transformer insulated property need to be monitored on-line, with real time, continuously reflect transformation
Device built-in electrical insulation deterioration condition.Transformer produces shelf depreciation, existing detection transformer insulated property when producing insulating properties defect
Device, typically local discharge current is monitored, shelf depreciation is the process to accumulate gradually, once occur serious to put
Electric fault, can cause irremediable loss, and some conventional protections can not find the slight change of this shelf depreciation,
The shelf depreciation of transformer is effectively monitored, insulation protection and whole circuit system safe operation tool for transformer
It is of great importance.The prior art to transformer carry out Partial Discharge Detection when, be typically only to end shield of high-voltage bushing lead-out wire into
Row current detecting, in practical application, some high voltage bushing terminal Folding-Screen can not be opened, and comprehensive insulating properties detection, should be also
Electric current inspection is carried out including the high voltage bushing terminal Folding-Screen ground wires to that cannot open, without the middle pressure of casing end Folding-Screen or low-tension bushing etc.
Survey, comprehensive current detecting, can guarantee that the accuracy that insulating properties judges.
Utility model content
The utility model provides transformer insulated property detection device, solves the accurate of insulating properties judgement existing in the prior art
The problem of property is low.
The utility model solves the above problems by the following technical programs：
Transformer insulated property detection device, including discharge current testing circuit, overvoltage detection circuit, power frequency Leakage Current
Detection circuit, scalable coiling current detection circuit, at least one ultrahigh-frequency current detection circuit, signal conditioning circuit, data are adopted
Storage and radio communication circuit；The discharge current testing circuit is installed on the interface of bottom shielding of bushing lead-out wire, described to put
Electric current detection circuit is inputted to data collector through signal conditioning circuit；The overvoltage detection circuit is installed on bottom shielding of bushing
The interface of lead-out wire, the overvoltage detection circuit are inputted to data collector through signal conditioning circuit；The power frequency leakage
Current detection circuit is installed on the interface of bottom shielding of bushing lead-out wire, and the power frequency Leakage Current detection circuit is through signal condition electricity
Road is inputted to data collector；The scalable coiling current detection circuit is installed on bushing shell for transformer root, described scalable
Coiling current detection circuit is inputted to data collector through signal conditioning circuit；The ultrahigh-frequency current detection circuit, which is installed on, to be become
On the ultra-high frequency antenna of depressor internally and/or externally, each ultrahigh-frequency current detection circuit through signal conditioning circuit input to
Data collector；The output data of the data collecting card is transmitted to exterior terminal through radio communication circuit.
Further comprise broadband current detection circuit；The broadband current detection circuit is installed on neutral ground
At line and/or iron core grounding line, the broadband current detection circuit is inputted to data collector through signal conditioning circuit.
Further, the discharge current testing circuit is current sensor, mainly by magnetic core, coil, integrating resistor group
Into；The magnetic core is closo annulus skeleton；The coil is the 0.5mm copper enameled wires of 30 circles；The integrating resistor is 50 Europe
Nurse.
Further, the overvoltage detection circuit is Zenith tracking sensor, mainly by overvoltage magnetic core, overvoltage
Coil, overvoltage integrating resistor composition；The overvoltage magnetic core is closo annulus skeleton；The overvoltage coil is 80 circles
0.5mm copper enameled wires；The overvoltage integrating resistor is 3 ohm.
Further, the power frequency Leakage Current detection circuit is shunt capacitance Coil Compensation Zero flux current sensor.
Further, the scalable coiling current detection circuit is scalable coiling current sensor, main to include modeling
Expect hose, coil, permanent magnet and terminal resistance；Magnetic powder is filled with the plastic flexible pipe, on the plastic flexible pipe
Even coiling, in coil both ends access terminal resistance, plastic flexible pipe both ends are linked together by permanent magnet so that plastics are soft
Pipe is internally formed close access；The scalable coiling current sensor is wrapped in bushing shell for transformer root.
Further comprise excess voltage protection；The discharge current testing circuit is installed on set through overvoltage crowbar
The interface of pipe end Folding-Screen lead-out wires；The overvoltage detection circuit is installed on bottom shielding of bushing lead-out wire through excess voltage protection
Interface；The power frequency Leakage Current detection circuit is installed on the interface of bottom shielding of bushing lead-out wire through excess voltage protection.
Further comprise multi-channel switch circuit；Each ultrahigh-frequency current detection circuit is through multi-channel switch electricity
Road, signal conditioning circuit are inputted to data collector.
Compared with prior art, there are following features：
1st, complete detection is carried out to the insulating properties of transformer according to the structure of transformer and operation principle, in different structure ruler
Very little Transformer Bushing Tap draws line interface, bushing shell for transformer root or inconvenience and installs the position of fixed dimension sensor, surpasses
Corresponding current detection circuit is installed at high frequency antenna, gathers shelf depreciation electric current, overvoltage electric current, the power frequency leakage of transformer
Electric current, without the shelf depreciation electric current and ultra-high frequency antenna electric current at the Folding-Screen ground wires of casing end, the insulating properties of transformer is carried out
Check comprehensively, improve the accuracy that insulating properties judges；
2nd, the powered current detection circuit of installing broad-band at neutral ground line, at iron core grounding line interface, in iron core grounding
The shelf depreciation of transformer is detected at line, judges to provide data basis for insulating properties, helps to further improve insulating properties judgement
Accuracy；
3rd, discharge current testing circuit, overvoltage detection circuit, power frequency Leakage Current detection circuit are through overvoltage protection electricity
Road is installed on the interface of bottom shielding of bushing lead-out wire, and excess voltage protection is lightning surge, transformer operating occur excessively electric
The normal operation of above three circuit is protected when pressure, transformer external short circuit overvoltage, maintains the stability of the utility model；
4th, data collector interface is limited, sets multy-way switching to open in the output terminal of multiple ultrahigh-frequency current detection circuits
Close, data collector can be obtained the electric current of each hyperfrequency power detection circuit by switching channel, realize most optimum distribution of resources.
Brief description of the drawings
Fig. 1 is the utility model structural principle block diagram.
Embodiment
The utility model is described in further detail with reference to embodiments, but the utility model is not limited to these implementations
Example.
Existing bushing shell for transformer divides high pressure, middle pressure, low-tension bushing, and main function is by transformer high, medium and low voltage winding
Lead lead to outside oil tank of transformer, so that the power grid with electric system is connected.Bushing shell for transformer is condenser-type terminal, main
Include insulator, capacitor core, contact tube, oil conservater, flange, voltage equalizing ball etc., there is a grounding sleeve near flange
Structure, condenser type fuse outermost layer are drawn and are grounded by being grounded from small casing, i.e. capacitor core end Folding-Screen ground connection, passes through last Folding-Screen
Ground wire can be with parameters such as the dielectric loss of test transformer casing, casing end Folding-Screen insulation resistances, capacitance of bushing.Transported in transformer
During row, last Folding-Screen need to ensure reliable ground, destroy, can produce when inside transformer insulating layer is mixed into air or insulating properties occurs
Local discharge signal, when Lightning disturbance ripple invades transformer along high-voltage conducting wires, can produce electric current, through last Folding-Screen on capacitance of bushing
Ground wire flows into the earth.Therefore, the current signal on monitoring sleeve end Folding-Screen ground wires, can grasp the state of insulation of transformer.
High voltage bushing terminal Folding-Screen can usually be opened, and can be directly connected to lead-out wire and be carried out current monitoring, but the bushing having
Last Folding-Screen does not have lead-out wire, or high voltage bushing terminal Folding-Screen does not allow to open, and middle pressure, low-tension bushing are tied even without casing end Folding-Screen
Structure, it is necessary to current detection circuit is set according to the concrete condition of casing, realizes the complete detection to insulating properties.
The utility model provides transformer insulated property detection device, including discharge current testing circuit, Zenith tracking electricity
Road, power frequency Leakage Current detection circuit, scalable coiling current detection circuit, at least one ultrahigh-frequency current detection circuit, signal
Modulate circuit, data collector and radio communication circuit；The discharge current testing circuit is installed on bottom shielding of bushing lead-out wire
Interface, the discharge current testing circuit inputted to data collector through signal conditioning circuit；The Zenith tracking electricity
Road is installed on the interface of bottom shielding of bushing lead-out wire, and the overvoltage detection circuit is inputted to data acquisition through signal conditioning circuit
Device；The power frequency Leakage Current detection circuit is installed on the interface of bottom shielding of bushing lead-out wire, the power frequency Leakage Current detection
Circuit is inputted to data collector through signal conditioning circuit；The scalable coiling current detection circuit is installed on bushing shell for transformer
Root, the scalable coiling current detection circuit are inputted to data collector through signal conditioning circuit；The ultrahigh-frequency current
Detection circuit is installed on the ultra-high frequency antenna of inside transformer and/or outside, and each ultrahigh-frequency current detection circuit is through letter
Number modulate circuit is inputted to data collector；The output data of the data collecting card is transmitted to exterior whole through radio communication circuit
End.
Discharge current testing circuit directly detection has the discharge current of the high voltage bushing terminal Folding-Screen of lead-out wire, for discharge pulse
Signal is detected.In the prior art, the frequency band of ground wire is not wide enough, has distortion, this practicality to high frequency (more than 1MHz) signal
New offer discharge current testing circuit, it is main to include discharge current sensor, the discharge current sensor mainly by magnetic core,
Coil, integrating resistor composition；The magnetic core is closo annulus skeleton；The coil is the 0.5mm copper enameled wires of 30 circles；It is described
Integrating resistor is 50 ohm, and during use by discharge current sensor sleeve on lead-out wire, the setting of above-mentioned parameter, solves to connect
The problem of ground wire frequency band is not wide enough.The discharge current sensor is shielded using metal shell.
Casing can produce overvoltage after being subject to lightning impulse, and weak alleviate of inside transformer insulation may be destroyed, transformation
For device winding there may be deformation, overvoltage frequency flows through the electric current of bushing shell for transformer end Folding-Screen ground wires most between 1KHz-1MHz
Amplitude can arrive 1000A；It can be produced when line fault, isolator operation zero load busbar, operation no-load transformer and operate electricity
Pressure, can reach 2-3 times of transformer rated voltage, therefore, it is necessary to the electric current by detecting casing when switching overvoltage is serious
To judge the insulating properties of transformer.Overvoltage detection circuit is Zenith tracking sensor, mainly by overvoltage magnetic core, overvoltage
Coil, overvoltage integrating resistor composition；The overvoltage magnetic core is closo annulus skeleton；The overvoltage coil is 80 circles
0.5mm copper enameled wires；The overvoltage integrating resistor is 3 ohm.The voltage detecting sensor is shielded using metal shell
Cover.
The usual very little of leakage current of casing end Folding-Screen, is milliampere level, live serious interference, high want is proposed to measurement diagonal difference
Ask, principle, performance and the form of power frequency leakage current detection circuit directly influence the precision and reliability of electric current acquisition, it is necessary to
Suitable current sensor is selected to monitor the faint current signal.The power frequency Leakage Current detection circuit of the utility model exists
A shunt capacitance coil is added on main magnetic core, forms shunt capacitance Coil Compensation Zero flux current sensor, and use metal
Housing shroud.The coil of a shunt capacitance is added on main magnetic core, can be reduced than difference and angular difference.
On the bushing that no lead-out wire or casing end Folding-Screen do not allow opening, and without in the Folding-Screen structures of casing end
In pressure, low-tension bushing, scalable coiling current detection circuit need to be used to carry out current detecting.The scalable coiling current detecting
Circuit is scalable coiling current sensor, is retractable structure, mainly including plastic flexible pipe, coil, permanent magnet and terminal electricity
Resistance；Magnetic powder is filled with the plastic flexible pipe, the uniform coiling on the plastic flexible pipe, is accessed eventually at coil both ends
Resistance is held, plastic flexible pipe both ends are linked together by permanent magnet so that plastic flexible pipe is internally formed close access；It is described to stretch
Contracting coiling current sensor is wrapped in bushing shell for transformer root.
The frequency band of local discharge superhigh frequency detection is wider, and the shelf depreciation information of acquisition is also relatively more, obtains transformer
Uhf electromagnetic wave signal, can show the characteristic that more shelf depreciations possess.The utility model is equipped with least one hyperfrequency electricity
Current detection circuit, the ultra-high frequency antenna installed in inside transformer and/or outside is built-in ultrahigh-frequency current detection circuit and outer
Ultrahigh-frequency current detection circuit is put, the two circuit structure is identical, and the ultra-high frequency signal inside and outside transformer is detected, and has model
The characteristics of enclosing big, high sensitivity, low noise.The frequency range of hyperfrequency is between 350MHz-1.5GHZ.
Signal conditioning circuit is mainly bandpass filter, preamplifier and envelope detector.Bandpass filter allows one
The signal in frequency range is determined by the way that another part is then suppressed；The signal received is carried out low noise by preamplifier
Amplification, can meet its input range when making it into envelope detector；Envelope detector is restored from amplitude-modulated signal to be become with envelope
The consistent former modulated signal of law.
Data collector gathers the data of each detection circuit using single buffer acquisition mode, and the data of collection pass through channel radio
Letter circuit is sent to exterior terminal.
Neutral point should be grounded and iron core grounding line also carries out current detecting, the utility model sets wideband belt current
Detection circuit carries out it current detecting, and the broadband current detection circuit is installed on neutral ground line and/or iron core connects
At ground wire, the broadband current detection circuit is inputted to data collector through signal conditioning circuit.Broadband current detecting electricity
The frequency band on road is 1KHz-40MHz.
The utility model further comprises excess voltage protection；The discharge current testing circuit is through overvoltage protection electricity
Road is installed on the interface of casing end Folding-Screen lead-out wires；The overvoltage detection circuit is installed on casing end through excess voltage protection
Shield the interface of lead-out wire；The power frequency Leakage Current detection circuit is installed on bottom shielding of bushing lead-out wire through excess voltage protection
Interface.Excess voltage protection, protection discharge current testing circuit, overvoltage detection circuit, power frequency Leakage Current are set
Detection circuit.
Further comprise multi-channel switch circuit；Each ultrahigh-frequency current detection circuit is through multi-channel switch electricity
Road, signal conditioning circuit are inputted to data collector.The multi-channel switch of the utility model selects 1 switch for 8, to multipair 8 tunnel
Built-in ultrahigh-frequency current detection circuit and external ultrahigh-frequency current detection circuit switch into row of channels.
The course of work of the utility model is：
Discharge current testing circuit, overvoltage detection circuit, power frequency Leakage Current detection circuit have detected high pressing sleeve respectively
Discharge current, overvoltage electric current and the power frequency Leakage Current of pipe end Folding-Screen lead-out wires, detection signal are inputted to number after signal condition
Exterior terminal is transmitted to according to collector, and by radio communication circuit；Scalable coiling current detection circuit, which is installed on, not to be drawn
Outlet or casing end Folding-Screen do not allow on the bushing opened, and without on the middle pressures of casing end Folding-Screen structures, low-tension bushing, inspection
Discharge current is surveyed, the signal detected is inputted to data collector after signal condition, and is transmitted to by radio communication circuit
Exterior terminal；Broadband current detection circuit detects the electric current at neutral ground line and/or iron core grounding line, the letter detected
Input is transmitted to exterior terminal to data collector, and by radio communication circuit number after signal condition；Each ultrahigh-frequency current
The signal that detection circuit detects is inputted to data collector after multi-channel switch circuit and signal conditioning circuit, and is passed through
Radio communication circuit is transmitted to exterior terminal.
Claims (8)
1. transformer insulated property detection device, it is characterised in that：
Including discharge current testing circuit, overvoltage detection circuit, power frequency Leakage Current detection circuit, the inspection of scalable coiling electric current
Slowdown monitoring circuit, at least one ultrahigh-frequency current detection circuit, signal conditioning circuit, data collector and radio communication circuit；
The discharge current testing circuit is installed on the interface of bottom shielding of bushing lead-out wire, and the discharge current testing circuit is through letter
Number modulate circuit is inputted to data collector；The overvoltage detection circuit is installed on the interface of bottom shielding of bushing lead-out wire, institute
Overvoltage detection circuit is stated to input to data collector through signal conditioning circuit；The power frequency Leakage Current detection circuit is installed on
The interface of bottom shielding of bushing lead-out wire, the power frequency Leakage Current detection circuit are inputted to data acquisition through signal conditioning circuit
Device；The scalable coiling current detection circuit is installed on bushing shell for transformer root, the scalable coiling current detection circuit
Inputted through signal conditioning circuit to data collector；The ultrahigh-frequency current detection circuit is installed in inside transformer and/or outside
On the ultra-high frequency antenna in portion, each ultrahigh-frequency current detection circuit is inputted to data collector through signal conditioning circuit；It is described
The output data of data collector is transmitted to exterior terminal through radio communication circuit.
2. transformer insulated property detection device according to claim 1, it is characterised in that：
Further comprise broadband current detection circuit；The broadband current detection circuit is installed on neutral ground line
And/or at iron core grounding line, the broadband current detection circuit is inputted to data collector through signal conditioning circuit.
3. transformer insulated property detection device according to claim 1, it is characterised in that：
The discharge current testing circuit is current sensor, is mainly made of magnetic core, coil, integrating resistor；The magnetic core is
Closo annulus skeleton；The coil is the 0.5mm copper enameled wires of 30 circles；The integrating resistor is 50 ohm.
4. transformer insulated property detection device according to claim 1, it is characterised in that：
The overvoltage detection circuit is Zenith tracking sensor, is mainly accumulated by overvoltage magnetic core, overvoltage coil, overvoltage
Sub-resistance forms；The overvoltage magnetic core is closo annulus skeleton；The overvoltage coil is the 0.5mm copper enamel-covers of 80 circles
Line；The overvoltage integrating resistor is 3 ohm.
5. transformer insulated property detection device according to claim 1, it is characterised in that：The power frequency Leakage Current detection
Circuit is shunt capacitance Coil Compensation Zero flux current sensor.
6. transformer insulated property detection device according to claim 1, it is characterised in that：
The scalable coiling current detection circuit is scalable coiling current sensor, mainly including plastic flexible pipe, coil, forever
Magnet and terminal resistance；Magnetic powder is filled with the plastic flexible pipe, the uniform coiling on the plastic flexible pipe, online
Both ends access terminal resistance is enclosed, plastic flexible pipe both ends are linked together by permanent magnet so that plastic flexible pipe is internally formed closure
Path；The scalable coiling current sensor is wrapped in bushing shell for transformer root.
7. transformer insulated property detection device according to claim 1, it is characterised in that：
Further comprise excess voltage protection；The discharge current testing circuit is installed on casing end through overvoltage crowbar
The interface of Folding-Screen lead-out wires；The overvoltage detection circuit is installed on the interface of bottom shielding of bushing lead-out wire through excess voltage protection
Place；The power frequency Leakage Current detection circuit is installed on the interface of bottom shielding of bushing lead-out wire through excess voltage protection.
8. transformer insulated property detection device according to claim 1, it is characterised in that：
Further comprise multi-channel switch circuit；Each ultrahigh-frequency current detection circuit through multi-channel switch circuit,
Signal conditioning circuit is inputted to data collector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721345544.7U CN207301251U (en) | 2017-10-19 | 2017-10-19 | Transformer insulated property detection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721345544.7U CN207301251U (en) | 2017-10-19 | 2017-10-19 | Transformer insulated property detection device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207301251U true CN207301251U (en) | 2018-05-01 |
Family
ID=62273186
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721345544.7U Expired - Fee Related CN207301251U (en) | 2017-10-19 | 2017-10-19 | Transformer insulated property detection device |
Country Status (1)
| Country | Link |
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| CN (1) | CN207301251U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107589356A (en) * | 2017-10-19 | 2018-01-16 | 桂林师范高等专科学校 | Transformer insulated property detection means |
| CN110412418A (en) * | 2019-07-22 | 2019-11-05 | 国网湖北省电力有限公司电力科学研究院 | Insulating tube type busbar insulation diagnosis and localization method based on earth current measurement |
| CN111458604A (en) * | 2019-12-27 | 2020-07-28 | 广东电网有限责任公司电力科学研究院 | Transformer self-sensing-based oscillation type lightning impulse test system and method |
| CN114252749A (en) * | 2022-02-28 | 2022-03-29 | 国网湖北省电力有限公司检修公司 | Transformer partial discharge detection method and device based on multiple sensors |
-
2017
- 2017-10-19 CN CN201721345544.7U patent/CN207301251U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107589356A (en) * | 2017-10-19 | 2018-01-16 | 桂林师范高等专科学校 | Transformer insulated property detection means |
| CN110412418A (en) * | 2019-07-22 | 2019-11-05 | 国网湖北省电力有限公司电力科学研究院 | Insulating tube type busbar insulation diagnosis and localization method based on earth current measurement |
| CN111458604A (en) * | 2019-12-27 | 2020-07-28 | 广东电网有限责任公司电力科学研究院 | Transformer self-sensing-based oscillation type lightning impulse test system and method |
| CN114252749A (en) * | 2022-02-28 | 2022-03-29 | 国网湖北省电力有限公司检修公司 | Transformer partial discharge detection method and device based on multiple sensors |
| CN114252749B (en) * | 2022-02-28 | 2022-06-17 | 国网湖北省电力有限公司检修公司 | Transformer partial discharge detection method and device based on multiple sensors |
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Granted publication date: 20180501 Termination date: 20191019 |