CN104155626B - The system that ground potential climbing capacity resisted by a kind of detection voltage transformer - Google Patents

The system that ground potential climbing capacity resisted by a kind of detection voltage transformer Download PDF

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Publication number
CN104155626B
CN104155626B CN201410404021.XA CN201410404021A CN104155626B CN 104155626 B CN104155626 B CN 104155626B CN 201410404021 A CN201410404021 A CN 201410404021A CN 104155626 B CN104155626 B CN 104155626B
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voltage transformer
detected
electronic type
input
voltage
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CN104155626A (en
Inventor
冯宇
王晓琪
汪本进
王均梅
吴光斌
吴士普
王欢
靳邵平
廖志军
张春强
黄华
杜砚
邱进
徐思恩
焦飞
陈江波
李金忠
周翠娟
刘彬
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STATE GRID JIANGXI ELECTRIC POWER Co
TAIKAI MUTUAL INDUCTOR CO Ltd SHANDONG
State Grid Corp of China SGCC
China Electric Power Research Institute Co Ltd CEPRI
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STATE GRID JIANGXI ELECTRIC POWER Co
TAIKAI MUTUAL INDUCTOR CO Ltd SHANDONG
State Grid Corp of China SGCC
China Electric Power Research Institute Co Ltd CEPRI
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Abstract

The present invention provides the system that ground potential climbing capacity resisted by a kind of detection voltage transformer, and the system includes standard lightning impulse generator, controllable impedance L, adjustable resistor R, measurement apparatus;Standard lightning impulse generator is provided with the input and output side being connected respectively with the output end of industrial frequency experiment power supply and the input of electronic type voltage transformer to be detected, measurement apparatus are provided with two inputs being connected respectively with output and ground of electronic type voltage transformer to be detected, controllable impedance L two ends connect ground terminal and the adjustable resistor of electronic type voltage transformer to be detected respectively, and the other end of adjustable resistor is connected with grounded screen;Measurement apparatus include high-voltage probe and wave tracer.This system features in convenient, overcome emulation mode cannot simulating actual conditions completely shortcoming, functionally equivalent with the method that builds GIS test platform and cost is relatively low, quality can be carried out to product before hanging net operation examination and check on.

Description

The system that ground potential climbing capacity resisted by a kind of detection voltage transformer
Technical field:
The present invention relates to a kind of detecting system, it is electric that in particular to a kind of detection electronic type voltage transformer resists transient state ground The system that position raises invasive ability.
Background technology:
As the electric power mutual-inductor of the important converting equipment of a class, its enormous amount and widely distributed, it is mainly used in as meter The electrical secondary systems such as amount, control and relay protection provide metrical information.
Electronic mutual inductor in electric power mutual-inductor have insulation system simple, nothing magnetic saturation, certainty of measurement be high, transient state is rung The advantages of scope is big, small volume, output signal are digitized is answered, which can not only reduce the integrated cost of transformer station, it is often more important that The Reliability of Microprocessor and precision of protection device and metering device in system can be greatly improved, be therefore able in electrical network in recent years big Amount application.
In the electronic type voltage transformer (Electronic Voltage Transformer, EVT) for having put into operation at present Be mostly capacitive voltage division electronic voltage transformer based on capacitive divider principle.According to use occasion not With it is big that capacitance partial pressure type EVT can be divided in independent support type and GIS (Gas Insulated Substation) deposited formula two again Class.Applying formula EVT in GIS is used for GIS transformer station, typically adopts gas-insulated, mainly by capacitive divider, cylinder, benzvalene form insulation The composition such as son, signal picker and combining unit.Easily produce when GIS carries out the switchgear operation such as disconnecting switch, breaker Very fast transient overvoltage (the Very Fast Transient of raw frequency of oscillation up to dozens or even hundreds of million Overvoltage, VFTO), so as to often cause the transient state ground potential in GIS transformer station to raise (Transient Grounding Potential Rise, TGPR) phenomenon, causes heavy losses.TGPR can produce impact to applying formula EVT in GIS, threaten which exhausted Edge, interference even damage signal picker and its power supply.Therefore, in the design process for applying formula EVT product in GIS, need to grind Study carefully the impact of TGPR.
Impact using following three kinds of technique study TGPR to deposited formula EVT product in GIS at present
(1) simulation study.Using the power system simulation softwares such as EMTP, EMTDC/PSCAD, NETOMAC set up GIS and The model of EVT, by the voltage on simulation calculation acquisition EVT element, current parameters.This method is although simple and easy to do, but deposits Institute's established model cannot simulating actual conditions completely deficiency, and simulation study cannot substitute products test, it is therefore desirable to carry For applying the test method that formula EVT resists TGPR ability in a kind of detection GIS;
(2) the hanging net operation examination of EVT product.Although this method can make EVT operate in actual electric network, in view of electricity Strict demand of the network operation to security reliability, may make linked network EVT not experience most harsh service condition at all, also Cannot comprehensive verification product design correctness.Additionally, this method cannot be played before product export carries out what quality was checked on Effect;
(3) the GIS test platform comprising breaker, disconnecting switch is built, is produced using the operation of switchgear TGPR, examines to applying formula EVT product in GIS, and this method technically meets detection EVT product and resists TGPR ability Demand.But the practical experience of operation of power networks shows, the electricity for causing the very fast transient overvoltage of TGPR to be present in more than 420kV Among net, this is meant that if voltage of TGPR, GIS test platform consistent with grid operating conditions etc. will be simulated completely Level is necessarily higher than 420kV, involves great expense and the manufacture level of platform device is required higher.
Based on above-mentioned background, it is desirable to provide a kind of good economy performance, avoid building GIS test platform and the technology that facilitates implementation Scheme resists transient state ground potential climbing capacity detecting electronic type voltage transformer.
Content of the invention:
In order to overcome the drawbacks described above in the presence of prior art, the present invention provides a kind of detection voltage transformer and resists ground The system of current potential climbing capacity.
The present invention provide technical scheme be:The system that ground potential climbing capacity resisted by a kind of detection voltage transformer, institute The system of stating includes standard lightning impulse generator, controllable impedance L, adjustable resistor R, measurement apparatus;
Which thes improvement is that:The standard lightning impulse generator is provided with output end respectively with industrial frequency experiment power supply The input and output side connected with the input of electronic type voltage transformer to be detected, the measurement apparatus be provided with respectively with described Two inputs of the output and ground connection of electronic type voltage transformer to be detected, the controllable impedance L two ends are divided Do not connect the ground terminal of the electronic type voltage transformer to be detected and the adjustable resistor, the adjustable resistor another One end is connected with grounded screen;The measurement apparatus include high-voltage probe and wave tracer.
Preferably, the standard lightning impulse generator output has rise time similar with very fast transient overvoltage And the overvoltage of amplitude reaches the input of the electronic type voltage transformer to be detected.
Preferably, the output end of the input reception of the measurement apparatus electronic type voltage transformer to be detected is defeated The voltage signal for going out, the output electricity of voltage signal electronic type voltage transformer to be detected when raising for transient state ground potential Pressure.
Further, another input of the measurement apparatus receives the earth terminal of the electronic type voltage transformer to be detected The voltage signal of son output, voltage signal electronic type voltage transformer ground connection to be detected when raising for transient state ground potential The current potential of terminal.
Preferably, the controllable impedance L simulates ground terminal and the transformer station of the electronic type voltage transformer to be detected Lead-in inductance between grounded screen.
Preferably, the adjustable resistor R is by the earth resistance of the change modeling difference electric pressure transformer station of resistance.
Preferably, the high-voltage probe includes that input is connected with the electronic type voltage transformer output end to be detected First high-voltage probe and input second high-voltage probe connected with the electronic type voltage transformer ground terminal to be detected, institute Another input for stating the first high-voltage probe is connected with grounded screen respectively with another input of second high-voltage probe.
Further, first high-voltage probe and second high-voltage probe respectively will be mutual for the electronic type voltage to be detected The output signal of the output signal of sensor output end and the electronic type voltage transformer ground terminal to be detected proportionally contracts Little, the amplitude of the output signal is made within the scope of the input range of the wave tracer.
Further, the wave tracer is provided with output end and second high pressure respectively with first high-voltage probe Two inputs of the output end connection of probe;The wave tracer receives first high-voltage probe and second high pressure The two paths of signals of probe input, and the signal for receiving is shown, stored and analyzed.
Compared with immediate technical scheme, the present invention has following marked improvement:
1st, the electronic type voltage transformer that the present invention is provided resists ground potential climbing capacity detecting system, overcomes emulation side Method cannot simulating actual conditions completely shortcoming, quality can be carried out to product before hanging net operation examination and check on.
2nd, the present invention is produced using standard lightning impulse generator and is being risen with the very fast transient overvoltage inside GIS Similar overvoltage on the wave character such as time and amplitude, with GIS test platform of the structure comprising breaker, disconnecting switch The method for carrying out correlation test is compared, present invention saves cost of investment, the test period is short, workable.
3rd, the testing result that measurement apparatus are measured can be used as the reference frame for applying the product design of formula EVT in GIS, perfect electricity The mentality of designing and step of minor voltage transformer.
Description of the drawings:
Fig. 1 is the test connection figure of original employing GIS test platform;
Fig. 2 is the installation dimension figure of original employing GIS test platform;
Fig. 3 is the test principle figure that invention is provided;
Fig. 4 is the circuit theory diagrams of 4 grades of impulse voltage generators.
Specific embodiment:
For a better understanding of the present invention, present disclosure is done further with reference to Figure of description and example Explanation.
Fig. 1 and Fig. 2 are the test connection figure of the GIS test platform for examining electronic mutual inductor and installation dimension figure, this Test platform cost is high, manufacture difficulty is big.
The schematic diagram of the technical scheme that the present invention is provided is as shown in Figure 3:Detecting system by standard lightning impulse generator, Controllable impedance, adjustable resistor and measurement apparatus composition.
Using multistage impulse voltage generator superposition composition, which is input into side joint industrial frequency experiment to standard lightning impulse generator Power supply, the input of outlet side reception detection electronic type voltage transformer, for produce 500kV and above with GIS inside spy The similar input voltage on the wave character such as rise time and amplitude of fast transient overvoltage.
Fig. 4 is the elementary diagram of 4 grades of impulse voltage generators, wherein:T is power supply high voltage transformer;D is high for rectification Pressure silicon stack;R is protective resistance;R is charging resistor;C is per grade of main capacitance;CsIt is the stray capacitance over the ground of every grade of respective point;g1 For ignition pill gap;g2~g4For intermediate gap;g0For batching sphere gap;rfIt is per grade of wavefront resistance;rtIt is per grade of discharge resistance; CtFor load capacity.Different according to test demand, above-mentioned 4 grades of impulse voltage generators can be generalized to more than 4 grades so as to produce The surge voltage of raw difference amplitude.
Electronic type voltage transformer to be detected is input into the outlet side of side joint standard lightning impulse generator, and its outlet side is accessed The input side of measurement apparatus.
Controllable impedance is used for simulating between ground terminal and the grounding net of transformer substation of electronic type voltage transformer to be detected Lead-in inductance, its one end are connected with the ground terminal of electronic type voltage transformer to be detected and output signal are reached measurement apparatus Input side, the other end is connected with adjustable resistor.
Adjustable resistor by the change of resistance for simulating the earth resistance of each electric pressure transformer station, its one end with can Inductance is adjusted to be connected, the other end is connected with grounded screen.
Measurement apparatus receive the output signal of electronic type voltage transformer to be detected, and the output signal is reflected on transient state ground The output situation of the electronic type voltage transformer to be detected when potential rise height occurs, can be used for check and evaluation electronic type voltage mutual inductance The design parameter of device and insulation margin.
Measurement apparatus receive the output letter of controllable impedance and electronic type voltage transformer ground terminal connection to be detected Number, the output signal reflects the electricity for raising the electronic type voltage transformer ground terminal to be detected when occurring in transient state ground potential Position size, can be used as the reference frame of electronic type voltage transformer product design.
Measurement apparatus are mainly made up of high-voltage probe and wave tracer two parts, for the overvoltage letter for preventing from measuring Number by the parts damages in measurement apparatus, the voltage tolerance parameter of high-voltage probe is higher than electronic type voltage transformer output to be detected Terminal and the maximum value possible of two point voltage of ground terminal.The Measurement bandwidth of high-voltage probe is more than electronic type voltage mutual inductance to be detected Device lead-out terminal and the bandwidth of two point voltage of ground terminal.
The function of high-voltage probe be the electronic type voltage transformer to be detected that will enter into measurement apparatus output signal and The output signal of controllable impedance and electronic type voltage transformer ground terminal connection to be detected reduce by a certain percentage decay, Its size is made within the scope of the input range of wave tracer;Waveform recording device part is mainly used in showing, stores, analyzes It is input into signal therein.
Carry out detection test when, first, adjustment criteria lightning impulse wave producer so as to simulate with inside GIS The similar overvoltage on the wave character such as rise time and amplitude of very fast transient overvoltage, used as electronic type voltage to be detected The input voltage of transformer;
After electronic type voltage transformer to be detected obtains input voltage, it is mutual that measurement apparatus measure electronic type voltage to be detected The output signal of the output signal of sensor and controllable impedance and electronic type voltage transformer ground terminal connection to be detected.Root According to being actually needed, measurement apparatus this two-way output signal can be carried out waveform show, storage and analysis.
Embodiments of the invention are these are only, the present invention is not limited to, all in the spirit and principles in the present invention Within, any modification, equivalent substitution and improvement that is done etc., all applying within pending scope of the presently claimed invention.

Claims (7)

1. the system that ground potential climbing capacity resisted by a kind of detection voltage transformer, the system include that standard lightning impulse is sent out Raw device, controllable impedance L, adjustable resistor R, measurement apparatus;
It is characterized in that:The standard lightning impulse generator be provided with respectively with the output end of industrial frequency experiment power supply and to be detected Electronic type voltage transformer input connection input and output side, the measurement apparatus be provided with respectively with the electricity to be detected Two inputs of the output and ground connection of minor voltage transformer, the controllable impedance L two ends connect institute respectively State the ground terminal of electronic type voltage transformer to be detected and the adjustable resistor, the other end of the adjustable resistor with connect Earth mat is connected;The measurement apparatus include high-voltage probe and wave tracer;
The standard lightning impulse generator output has the mistake of rise time similar and amplitude with very fast transient overvoltage Voltage reaches the input of the electronic type voltage transformer to be detected;
One input of the measurement apparatus receives the voltage letter of the output end output of the electronic type voltage transformer to be detected Number, the output voltage of voltage signal electronic type voltage transformer to be detected when raising for transient state ground potential.
2. the system that ground potential climbing capacity resisted by a kind of detection voltage transformer as claimed in claim 1, it is characterised in that:
Another input of the measurement apparatus receives the electricity of the ground terminal output of the electronic type voltage transformer to be detected Pressure signal, the electricity of voltage signal electronic type voltage transformer ground terminal to be detected when raising for transient state ground potential Position.
3. the system that ground potential climbing capacity resisted by a kind of detection voltage transformer as claimed in claim 1, it is characterised in that:
The controllable impedance L is simulated between the ground terminal of the electronic type voltage transformer to be detected and grounding net of transformer substation Lead-in inductance.
4. the system that ground potential climbing capacity resisted by a kind of detection voltage transformer as claimed in claim 1, it is characterised in that:
The adjustable resistor R is by the earth resistance of the change modeling difference electric pressure transformer station of resistance.
5. the system that ground potential climbing capacity resisted by a kind of detection voltage transformer as claimed in claim 1, it is characterised in that:
The high-voltage probe includes that input first high pressure connected with the electronic type voltage transformer output end to be detected is visited Head and input second high-voltage probe connected with the electronic type voltage transformer ground terminal to be detected, first high pressure Another input of probe is connected with grounded screen respectively with another input of second high-voltage probe.
6. the system that ground potential climbing capacity resisted by a kind of detection voltage transformer as claimed in claim 5, it is characterised in that:
First high-voltage probe and second high-voltage probe are respectively by the electronic type voltage transformer output end to be detected Output signal and the output signal of the electronic type voltage transformer ground terminal to be detected proportionally reduce, make described defeated Go out the amplitude of signal within the scope of the input range of the wave tracer.
7. the system that ground potential climbing capacity resisted by a kind of detection voltage transformer as claimed in claim 6, it is characterised in that:
The wave tracer be provided with respectively with the output end of first high-voltage probe and the output of second high-voltage probe Two inputs of end connection;Wave tracer reception first high-voltage probe and second high-voltage probe are input into Two paths of signals, and the signal for receiving is shown, stored and analyzed.
CN201410404021.XA 2014-08-15 2014-08-15 The system that ground potential climbing capacity resisted by a kind of detection voltage transformer Active CN104155626B (en)

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