The dielectric response of paper oil insulation casing not blackouts monitoring system and method
Technical field
The invention belongs to paper oil insulation casing insulation state monitorings and diagnostic techniques field more particularly to a kind of paper oil insulation
The dielectric response of casing not blackouts monitoring system and method.
Background technique
Bushing shell for transformer is one of capital equipment of electric system, plays very important effect in the power system.Oil
Paper insulation casing malfunction or damage not only results in power outage, or even can cause substation equipment explosion, lead to fire, into one
Walk expansion accident range.The safe and stable operation of casing directly affects the stabilization of the even entire power grid of transformer, insulate to it
The monitoring of state and diagnostic significance are great.
When oil-filled equipment runing time is longer, since external humidification enters, micro- water in the oil of oil-filled equipment may cause
Content rises, casing insulation ag(e)ing.For the insulation condition diagnosis of oil-filled equipment, traditional high-voltage electrical apparatus test such as dielectric loss, electricity
Volume test, means are more single, and test data is influenced vulnerable to test condition, reflection insulation information is less, while needing to stop
Electricity, test period are long.
Summary of the invention
The purpose of the present invention is to provide a kind of dielectric response of paper oil insulation casing not blackouts monitoring system and method, with
Solve above-mentioned technical problem.The present invention can be achieved bushing shell for transformer effect of electromagnetic field not blackouts monitoring, by
Line monitoring data diagnose insulation and the ageing state of casing.Compared with conventional offline monitoring means, on-Line Monitor Device of the present invention
Be not required to have a power failure, the advantages such as monitoring information is abundant, real-time monitoring diagnosis.
In order to achieve the above objectives, the invention adopts the following technical scheme:
A kind of dielectric response of paper oil insulation casing not blackouts monitoring system, including high voltage bus, bushing, transformation
Device, voltage transformer, current transformer and data acquisition and procession unit;
Bushing built-in electrical insulation medium is paper oil insulation complex media;The inlet wire of high voltage bus is arranged in voltage transformer
Side, voltage transformer one end are connect with high voltage bus, and the other end is connect with data acquisition and procession unit;Current transformer setting
In the bottom shielding of bushing of bushing, the coil that the end shield lead of bushing passes through current transformer is arranged, current transformer
Output end connect with data acquisition and procession unit;Data acquisition and procession unit is used for voltage transformer, Current Mutual Inductance
Voltage signal that device measures respectively, current signal are converted to the dielectric loss value under different frequency harmonic voltage.
It further, further include fault diagnosis and alarm platform, fault diagnosis is adopted with alarm platform by optical fiber and data
Collection is connect with processing unit;Fault diagnosis is used to for the dielectric loss value that data acquisition and procession unit transmits being depicted as with alarm platform
Effect of electromagnetic field curve, and be compared with the model of the historical data of casing and experts database system.
Further, the dielectric loss value under different frequency harmonic voltage is the tangent value of voltage signal, current signal phase difference.
Further, voltage transformer uses capacitance type potential transformer.
Further, current transformer uses zero-flux current transformer;Compensation is provided in zero-flux current transformer
Winding, compensative winding is for providing exciting current.
Further, insulation crust is set between current transformer and end shield lead, and insulation crust is used for Current Mutual Inductance
Device and end shield lead wire insulation.
Further, insulation crust is made of epoxy resin or polytetrafluoroethylene (PTFE), and the thickness of insulation crust is greater than or waits
In 0.5mm.
Further, bushing top and high voltage bus junction are equipped with hemispherical grading shield.
Further, bottom shielding of bushing is set as hollow housing, and shell is made of aluminium, and thickness of shell is more than or equal to 1mm;
End shield lead is connect with shell using Spring connector plug.
The present invention also provides a kind of dielectric response of paper oil insulation casing not blackouts monitoring methods, comprising the following steps:
Step 1: by the voltage signal of the collected high voltage bus of voltage transformer and current transformer and bottom shielding of bushing
Current signal is transmitted to data acquisition and procession unit, and processing obtains the dielectric loss value under different frequency harmonic voltage;
Step 2: the dielectric loss value under the different frequency harmonic voltage of step 1 is transmitted to fault diagnosis and alarm platform;Therefore
The dielectric loss value of step 1 is depicted as effect of electromagnetic field curve with alarm platform by barrier diagnosis, and by effect of electromagnetic field curve with
The historical data of bushing and the model of experts database system are compared, and obtain the water content of bushing, pass through water content
Size diagnosis bushing operation and ageing state.
Compared with prior art, the beneficial effects of the present invention are:
The present invention provides a kind of dielectric response of paper oil insulation casing not blackouts monitoring systems, using on high voltage bus
Voltage transformer is set, using current transformer is arranged in bottom shielding of bushing;Compared with existing measuring device and measurement method, this
Invention does not need to be an externally injected into swept frequency excitation signal, directly using the harmonic voltage signal in electric system as dielectric response
The driving source of test has many advantages, such as that metrical information is abundant, measuring accuracy is high, safe and reliable, while having and being not required to have a power failure, in real time
The advantages such as monitoring, diagnosing.
Further, dielectric loss value is depicted as effect of electromagnetic field curve with alarm platform by setting fault diagnosis, by dielectric
Resonse characteristic is compared with the model of the historical data of casing and experts database system, obtains the water content of bushing,
Operation and the ageing state of bushing are diagnosed by the size of water content.
Detailed description of the invention
Fig. 1 is a kind of dielectric response not blackouts monitoring system and method schematic diagram of paper oil insulation casing of the invention;
Wherein, 1 high voltage bus, 2 bushings, 3 transformers, 4 voltage transformers, 5 bottom shielding of bushing, 6 current transformers, 7
Data acquisition and procession unit, 8 fault diagnosises and alarm platform.
Specific embodiment
It elaborates in the following with reference to the drawings and specific embodiments to the present invention.
With reference to shown in attached drawing 1, the present invention provides a kind of dielectric response of paper oil insulation casing not blackouts monitoring system, packets
Include high voltage bus 1, bushing 2, transformer 3, voltage transformer 4, current transformer 6, data acquisition and procession unit 7, event
Barrier diagnosis and alarm platform 8.
1 one end of high voltage bus connects bushing 2, and the other end is connected in substation's other equipment;The top of bushing 2
End is connect with high voltage bus 1, and the bottom end of bushing 2 is connect with 3 ontology of transformer.
The bottom shielding of bushing 5 of bushing 1 is hollow housing, and shell is cast structure, is made of aluminium material, thickness is greater than
Equal to 1mm, to meet electromagnetic shielding requirements, the end shield earthing of casing;End shield lead one end of bushing 2 is arranged in bushing
Inside 2, the other end passes through the cage connection of spring connection-peg and bottom shielding of bushing 5, avoids end shield lead to open a way in operation, causes
Voltage damages bushing 2.
Current transformer 6 is arranged in bottom shielding of bushing 5, and end shield lead passes through among the coil of current transformer 6;Electric current
It is provided with insulation crust between mutual inductor 6 and end shield lead, prevents generation between current transformer 6 and end shield lead from electrically connecing
Touching.Epoxy resin can be used in insulation crust or polytetrafluoroethylene (PTFE) production, the thickness of insulation crust are typically no less than 0.5mm.
Current transformer 6 uses zero-flux current transformer, compensative winding is arranged in zero-flux current transformer, for mentioning
For exciting current, the ratio difference and angular difference of current measurement are eliminated, measurement accuracy is improved.The harmonic wave electricity that current transformer 6 is tested
Stream signal amplitude range is 0~100mA, and harmonic current frequency range is 1Hz~1kHz.
The enter line side of high voltage bus 1 is arranged in voltage transformer 4, for monitoring the voltage of high voltage bus 1;Voltage transformer
4 use capacitance type potential transformer, can calculate voltage signal on high voltage bus 1 by obtaining its secondary side voltage.
Device can also be transformed using the transformation device to the voltage transformer low-voltage arm in substation in voltage transformer 4
It is realized using by the way of voltage transformer low-voltage arm parallel connection overvoltage and surge protective device, overvoltage and surge protective device
Preferable Transient Voltage Suppressor makes improved device measurement frequency band meet dielectric response test request.Voltage measurement signal
It is obtained from voltage transformer low-voltage arm capacitor, the voltage signal magnitude of voltage transformer low-voltage arm output is no more than 100V.
The harmonic voltage signal amplitude range that voltage transformer 4 is tested is 0~100V, and harmonic voltage frequency range is
1Hz~1kHz.
Current transformer 6 is connect by screened cable with data acquisition and procession unit 7;Voltage transformer 4 passes through double
Shielded cable is connect with data acquisition and procession unit 7, and data acquisition and procession unit 7 is by voltage transformer 4, current transformer
6 harmonic voltage signal, the current signals measured respectively carry out amplitude amplification, and high-frequency interferencing signal filters out, and is converted into unified electricity
Signal, and calculate the dielectric loss value under different frequency harmonic voltage;Dielectric loss value under different frequency harmonic voltage be voltage signal,
The tangent value of current signal phase difference.
Data acquisition and procession unit 7 is connect by optical fiber with fault diagnosis with alarm platform 8, is adopted data by optical fiber
Collection exports the dielectric loss value under different frequency harmonic voltage with processing unit 7 and is transmitted to fault diagnosis and alarm platform 8.
Jie under the different frequency harmonic voltage that fault diagnosis and alarm platform 8 transmit data acquisition and procession unit 7
Damage value is depicted as effect of electromagnetic field curve, and by the historical data and experts database of effect of electromagnetic field curve and bushing 2
The model of system is compared, and obtains the water content of bushing 2, and the operation of bushing 2 is diagnosed by the size of water content
And ageing state.
The present invention also provides a kind of dielectric response of paper oil insulation casing not blackouts monitoring methods, comprising the following steps:
Step 1: by the voltage signal and bottom shielding of bushing of voltage transformer 4 and the collected high voltage bus 1 of current transformer 6
5 current signal is transmitted to data acquisition and procession unit 7, and processing obtains the dielectric loss value under different frequency harmonic voltage;
Step 2: the dielectric loss value under the different frequency harmonic voltage of step 1 is transmitted to fault diagnosis and alarm platform 8;Therefore
The dielectric loss value of step 1 is depicted as effect of electromagnetic field curve with alarm platform 8 by barrier diagnosis, and by effect of electromagnetic field curve with
The historical data of bushing 2 and the model of experts database system are compared, and the water content of bushing 2 are obtained, by aqueous
The operation of the size diagnosis bushing 2 of amount and ageing state.
Below it is practical application embodiment:
In practical applications, current transformer of the present invention is separately mounted to the A phase high voltage bushing terminal of transformer 3
In screen, in B phase end shield of high-voltage bushing and in C phase end shield of high-voltage bushing, it is female that the voltage transformer is connected to A phase high pressure
The enter line side of line, the enter line side of B phase high voltage bus, the enter line side of C phase high voltage bus, three-phase monitoring signals simultaneous transmission to data
Acquisition and processing unit 7, calculate the dielectric loss value under different frequency harmonic voltage, dielectric loss value are transmitted to failure by optical fiber and is examined
Disconnected and alarm platform 8;The different frequency harmonic voltage that fault diagnosis and alarm platform 8 transmit data acquisition and procession unit 7
Under dielectric loss value be depicted as effect of electromagnetic field curve, the effect of electromagnetic field curve of A, B, C three-phase casing is laterally compared, together
When with the model of the historical data of bushing 2 and experts database system carry out it is longitudinal compare, obtain the water content of bushing 2,
Operation and the ageing state of bushing 2 are diagnosed by the size of water content.
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications are also answered
It is considered as protection scope of the present invention.