CN206321711U - A kind of portable impact current feedback circuit measured for impulse earthed resistance - Google Patents
A kind of portable impact current feedback circuit measured for impulse earthed resistance Download PDFInfo
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- CN206321711U CN206321711U CN201621473075.2U CN201621473075U CN206321711U CN 206321711 U CN206321711 U CN 206321711U CN 201621473075 U CN201621473075 U CN 201621473075U CN 206321711 U CN206321711 U CN 206321711U
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Abstract
The utility model discloses a kind of portable impact current feedback circuit measured for impulse earthed resistance, including main circuit, control circuit；Main circuit is used to produce dash current, and be connected with control circuit, control circuit is used to control main circuit to carry out pulsed discharge, main circuit tail end is connected respectively to electric current injector and the backflow pole of grounding body, injector is connected to pulse analyser, pulse analyser measurement end is connected to oscillograph, and also including the Rogowski coil for being serially connected in backflow pole, Rogowski coil is connected to oscillograph.The utility model obtains rush of current to grounding body and measured, measured surge voltage and current waveform will definitely really be leaned on, equipment volume is small, it is lightweight, transport and easy to assembly, experimentation cost is low, it is simple to operate, substantially reduce test dangerous, and charging voltage highest can reach 50kV, and dash current amplitude highest can reach 3kA.
Description
Technical field
The utility model belongs to Grounding Technology of Modern Power System field, more particularly to a kind of to be used for what impulse earthed resistance was measured
Portable impact current feedback circuit.
Background technology
Earthing or grounding means is to ensure that power system safety and stability runs indispensable pith.With power system capacity
Continuous increase, the continuous improvement of voltage class, the influence of the transient fault electric current to system such as operation, thunder and lightning be also increasing,
Therefore higher requirement is proposed to the diffusing effect of earthing or grounding means under impact.Operation of Electric Systems experience have shown that, it is most of
Transmission line of electricity trip accident is all due to that transmission line of lightning strike or shaft tower cause tripping operation caused.According to electric network fault categorised statistical form
Bright, in total tripping times of high-tension line operation, the number of times caused by thunderbolt accounts for 40%~70%.Electric power line pole tower grounding body
Impulse earthed resistance tower top when directly determining thunderbolt current potential, so as to influence overvoltage that insulator chain bears and counterattack general
Rate.Therefore in the design of overhead line structures, the impulse earthed resistance value of its earthing or grounding means has important meaning to the lightning protection of circuit
Justice.But electric power line pole tower earthing or grounding means is still using specific in China and international transmission line of electricity Lightning Protection Analysis calculate
The lumped parameter resistance of value is simulated.In fact, under dash current effect, the power transformation when earth resistance of earthing or grounding means is one
Resistance, is presented complicated nonlinear characteristic, is at present to cause lightning protection come analogue ground device using the lumped parameter resistance of particular value
Analysis result differs larger with the actual running results, it is impossible to the main cause of the accurate lightning protection properties for calculating actual transmission line of electricity.
At present, the research to impulse earthed resistance is broadly divided into two major classes, and one is theoretical simulation research, and two be that experiment is ground
Study carefully.With the development of computer technology, simulation study has obtained very big development.The transient characterisitics of simulated ground device mainly have
Following several method：Transmission line theory, Circuit theory, Theory of Electromagnetic Field, finite element method etc., but these methods have certain
Limitation, and the impact characteristics of actual earthing or grounding means can have certain deviation, therefore experimental study is still that research impact connects
The most directly effective method of ground resistance.The inductive effect and spark of impulse earthed resistance can be studied well by field test
Effect.But the impulse current generator of current real model experiment is bulky, complex operation, transport and assembled in situ are difficult, once
Experimentation cost is very high, and the live shock-testing of high pressure is dangerous higher, so developing what is measured for impulse earthed resistance
Portable impact current feedback circuit has important meaning.
The content of the invention
The technical problems to be solved in the utility model is：A kind of portable impact measured for impulse earthed resistance is provided
Current feedback circuit, measurement is accurate, and small volume is lightweight, transports and easy to assembly, experimentation cost is low, simple to operate, significantly
Reduction test is dangerous, to solve the technical problem of impulse earthed resistance field test presence.
The technical scheme that the utility model is taken is：A kind of portable impact electric current hair measured for impulse earthed resistance
Raw device, including main circuit, control circuit；Main circuit is used to produce dash current, and is connected with control circuit, and control circuit is used for
Main circuit is controlled to carry out pulsed discharge；Main circuit tail end is connected respectively to electric current injector and the backflow pole of grounding body, injector
Pulse analyser is connected to, the measurement end of pulse analyser is connected to oscillograph, also including the Rogowski coil for being serially connected in backflow pole,
Rogowski coil is connected to oscillograph, and oscillograph is used to measure the pulse voltage of grounding body and the waveform of electric current.
It is preferred that, above-mentioned main circuit includes AC AC powers, pressure regulator T1, rectification silicon stack D1, charging resistor R1, voltage stabilizing electricity
Hold C1, high-frequency inversion bridge, step-up transformer T2, rectification silicon stack D2, charging resistor R2, divider, main capacitance C2, discharge switch
S, wave regulating resistor R3Pressure regulator T is connected to harmonic inductance L, AC ac power output1, pressure regulator T1Export one end concatenation whole
Flow silicon stack D1With charging resistor R1, electric capacity of voltage regulation C1One end is connected to charging resistor R1, the other end is connected to pressure regulator T1The other end,
Electric capacity of voltage regulation C1Output end is parallel with high-frequency inversion bridge, and high-frequency inversion bridging is connected to step-up transformer T2, step-up transformer T2Output
Rectification silicon stack D is serially connected with one end2With charging resistor R2, divider and main capacitance C2Two ends, which are connected respectively to, after parallel connection fills
Resistance R2With step-up transformer T2Export the other end, main capacitance C2Positive pole is serially connected with discharge switch S, wave regulating resistor R3And harmonic
Inductance L, the electric current injector of harmonic inductance connection to grounding body, the current reflux pole of grounding body is connected to step-up transformer T2Separately
One end, discharge switch S is sphere gap switch, is acted by magnet control ball gap, and electromagnet is connected to control circuit, main capacitance C2Two
End is connected with the sample circuit of collection voltages, and sample circuit includes divider and ADC change-over circuits, and sample circuit is connected to
Control circuit.
It is preferred that, above-mentioned high-frequency inversion bridge is by transistor Q1, transistor Q2, transistor Q3, transistor Q4Bridge joint is formed, brilliant
Body pipe Q1, transistor Q2, transistor Q3With transistor Q4Use insulated gate bipolar transistor.
It is preferred that, above-mentioned divider is by high-voltage arm resistance R of the resistance for 50M Ω4It is low-voltage arm resistance R with resistance5String
Connect and form.
It is preferred that, above-mentioned main capacitance C2For two pressure-resistant 30kV, 1uF impulse capacitor series connection, main capacitance C2Negative pole connects
Ground.
It is preferred that, above-mentioned control circuit connection electromagnet, sample circuit, drive circuit and display circuit, electromagnet are used for
Discharge switch is controlled, sample circuit is connected to controller by ADC change-over circuits, for main capacitance C2Both end voltage adopt
Collection, drive circuit is used to be driven four transistors of high-frequency inversion bridge.
It is preferred that, above-mentioned a kind of portable impact current feedback circuit measured for impulse earthed resistance, also including leading back
Road case and control cabinet, control cabinet are connected in major loop case, major loop case by wire and optical fiber and install main circuit, in control cabinet
Control circuit and pressure regulator T are installed1, control cabinet surface is provided with for showing main capacitance C2The display screen of charging voltage, pressure regulator
T1Voltage-regulation knob, control discharge switch and high-frequency inversion bridge trigger button, emergency stop push button and power supply instruction
Lamp.
The beneficial effects of the utility model：Compared with prior art, the utility model is connected by the main circuit of dash current
Grounding body is connected to, and rush of current is carried out by controlling circuit, using Rogowski coil and pulse analyser connection oscillograph docking
Ground body rush of current is measured, and measured surge voltage and current waveform will definitely really be leaned on, and equipment volume is small, lightweight, fortune
Defeated and easy to assembly, experimentation cost is low, simple to operate, and it is dangerous to substantially reduce test, and charging voltage highest can be with
50kV is reached, dash current amplitude highest can reach 3kA, live impulse earthed resistance is tested and anticipated with important engineering
Justice.
Brief description of the drawings
Fig. 1 is portable impact current feedback circuit main circuit and test loop schematic diagram；
Fig. 2 is control cabinet front panel schematic diagram.
Embodiment
Below in conjunction with the accompanying drawings and the utility model is described further specific embodiment.
Embodiment 1：A kind of portable impact current feedback circuit measured for impulse earthed resistance, including main circuit, control
Circuit processed；Main circuit is used to produce dash current, and is connected with control circuit, and control circuit is used to control main circuit to enter horizontal pulse
Electric discharge, main circuit tail end is connected respectively to electric current injector and the backflow pole of grounding body, and injector is connected to pulse analyser, arteries and veins
Rush divider measurement end and be connected to oscillograph, also including the Rogowski coil for being serially connected in backflow pole, Rogowski coil is connected to oscillograph,
Oscillograph is used to measure the pulse voltage of grounding body and the waveform of electric current.
It is preferred that, above-mentioned main circuit includes AC AC powers, pressure regulator T1, rectification silicon stack D1, charging resistor R1, voltage stabilizing electricity
Hold C1, high-frequency inversion bridge, step-up transformer T2, rectification silicon stack D2, charging resistor R2, divider, main capacitance C2, discharge switch
S, wave regulating resistor R3Pressure regulator T is connected to harmonic inductance L, AC ac power output1, pressure regulator T1Export one end concatenation whole
Flow silicon stack D1With charging resistor R1, electric capacity of voltage regulation C1One end is connected to charging resistor R1, the other end is connected to pressure regulator T1The other end,
Electric capacity of voltage regulation C1Output end is parallel with high-frequency inversion bridge, and high-frequency inversion bridging is connected to step-up transformer T2, step-up transformer T2Output
Rectification silicon stack D is serially connected with one end2With charging resistor R2, divider and main capacitance C2Two ends, which are connected respectively to, after parallel connection fills
Resistance R2With step-up transformer T2Export the other end, main capacitance C2Positive pole is serially connected with discharge switch S, wave regulating resistor R3And harmonic
Inductance L, the electric current injector of harmonic inductance connection to grounding body, the current reflux pole of grounding body is connected to step-up transformer T2Separately
One end, discharge switch S is sphere gap switch, is acted by magnet control ball gap, and electromagnet is connected to control circuit, main capacitance C2Two
End is connected with the sample circuit of collection voltages, and sample circuit includes divider and ADC change-over circuits, and sample circuit is connected to
Control circuit.
It is preferred that, above-mentioned high-frequency inversion bridge is by transistor Q1, transistor Q2, transistor Q3, transistor Q4Bridge joint is formed, brilliant
Body pipe Q1, transistor Q2, transistor Q3With transistor Q4Use insulated gate bipolar transistor.
It is preferred that, above-mentioned divider is by high-voltage arm resistance R of the resistance for 50M Ω4It is low-voltage arm resistance R with resistance5String
Connect and form.
It is preferred that, above-mentioned main capacitance C2For two pressure-resistant 30kV, 1uF impulse capacitor series connection, main capacitance C2Negative pole connects
Ground.
It is preferred that, above-mentioned control circuit connection electromagnet, sample circuit, drive circuit and display circuit, electromagnet are used for
Discharge switch is controlled, sample circuit is connected to control circuit, for main capacitance C2Both end voltage collection, drive circuit is used for
Four transistors of high-frequency inversion bridge are driven.
It is preferred that, above-mentioned a kind of portable impact current feedback circuit measured for impulse earthed resistance, also including leading back
Road case and control cabinet, control cabinet are connected in major loop case, major loop case by wire and optical fiber and install main circuit, in control cabinet
Control circuit and pressure regulator T are installed1, control cabinet surface is provided with for showing main capacitance C2The display screen of charging voltage, pressure regulator
T1Voltage-regulation knob, control discharge switch and high-frequency inversion bridge trigger button, emergency stop push button and power supply instruction
Lamp.
In order to reduce the volume and weight of itself, this impulse current generator is not self-powered, it is necessary to outside offer 220V
Alternating current, need to provide battery and inverter during on-the-spot test.
Silicon stack D1、D2It is direct current to be all used for AC rectification.
Charging resistor R1Resistance be 40 Ω, the charging current for limiting electric capacity of voltage regulation, but do not make charging rate mistake
Slowly.
Electric capacity of voltage regulation C1For providing a galvanic current pressure, capacitance is 1000uF, pressure-resistant 500V.
Charging resistor R2Resistance be 1M Ω, the maximum charging current for limiting main capacitance is 50mA, but does not make to fill
Electric speed is excessively slow.
Insulated gate bipolar transistor Q1、Q2、Q3、Q4High-frequency inversion bridge is constituted, reverse frequency is 50kHz, Q1And Q3Drive
Dynamic signal is identical, Q2And Q4Drive signal it is identical, and the two drive signal phases differ 180 °, in order to prevent bridge arm direct pass,
1us Dead Time, Q are set1、Q2、Q3、Q4From pressure-resistant 500V, through-flow more than 10A transistor, it is ensured that its safety and stability work
Make.
Step-up transformer T2For high frequency transformer, no-load voltage ratio 1:140, rated voltage 50kV, rated capacity 3kVA, hold than identical
The Industrial Frequency Transformer volume of amount is much smaller.
Divider is used to measure main capacitance C2Both end voltage, and be shown in real time on control cabinet front panel, high-voltage arm
Resistance R4Resistance is 50M Ω, and low-voltage arm resistance is 5k Ω, and intrinsic standoff ratio is 10000.
Discharge switch S is sphere gap switch, by its action of magnet control, when control cabinet presses triggering button, electromagnetism Tie Tong
Electricity, ball stand-off distance punctures from rapid shortening, ball gap, and main capacitance docking conductive discharge produces dash current.
Main capacitance C2For two pressure-resistant 30kV, 1uF impulse capacitor is connected, and voltage is from 0 to the charging for charging to 50kV
Time is less than 2.5s.
Adjustable wave regulating resistor R3, resistance is 10 Ω, for adjusting impulse current waveform, and it is standard that can make waveform
2.6us/50us lightning current waveforms.
Adjustable harmonic inductance L, inductance value is 60uH, for adjusting impulse current waveform, and it is standard that can make waveform
2.6us/50us lightning current waveforms.
For guarantee test personal security, main capacitance C2It should be grounded nearby.
(2) implementation of control cabinet is as follows
There is pressure regulator T in control cabinet1With control circuit, control cabinet is connected by wire and optical fiber with major loop case.Control
Case panel is designed as shown in Fig. 2 be disposed with power supply indicator on front panel, charging voltage display screen, trigger button, voltage-regulation
Knob, emergency stop push button.
Power supply indicator is used to show whether the utility model is already connected to power supply, if indicator lamp is bright, illustrates that power supply is normal.
Charging voltage display screen shows C on main capacitance2Charging voltage, sample in divider, by digital-to-analogue conversion
After be shown on charactron.
Trigger button connects magnet control button and insulated gate bipolar transistor Q1、Q2、Q3、Q4Drive circuit, when
When trigger button is pressed, electromagnet action makes ball gap Distance Shortened, while latch actuation circuit, makes Q1、Q2、Q3、Q4All close
It is disconnected, stop main capacitance C2Charging.Voltage-regulation knob is connected with pressure regulator, and pressure regulator output voltage is changed by adjusting.Tightly
Anxious stop button is used for emergency power off, and electric capacity of voltage regulation and main capacitance are discharged, and stops experiment.
(3) in-site measurement implementation：
Backflow pole and Voltage Reference pole position are determined according to the size of grounding body and actual place size, by figure
Connection cloth circuits shown in 1, all connecting lines are all using sufficiently long insulation strut as on the ground, and testing current uses Roche line
Circle, voltage tester uses pulse analyser, and Rogowski coil and pulse analyser are connected to oscillograph, after all wiring checks are errorless
Just portable impact current feedback circuit battery main switch can be opened.Charging voltage can be just adjusted afterwards, trigger discharge measuring ripple
Shape.Change different charging voltage amplitudes, the voltage and current waveform under different dash currents can be measured, pass through analysis meter
Calculate, it is possible to obtain the impulse earthed resistance characteristic of tested grounding body.
The above, embodiment only of the present utility model, but protection domain of the present utility model do not limit to
In this, any one skilled in the art can readily occur in change in the technical scope that the utility model is disclosed
Or replace, it should all cover within protection domain of the present utility model, therefore, protection domain of the present utility model should be with the power
The protection domain that profit is required is defined.
Claims (7)
1. a kind of portable impact current feedback circuit measured for impulse earthed resistance, it is characterised in that：Including main circuit, control
Circuit processed；Main circuit is used to produce dash current, and is connected with control circuit, and control circuit is used to control main circuit to enter horizontal pulse
Electric discharge, main circuit tail end is connected respectively to electric current injector and the backflow pole of grounding body, and injector is connected to pulse analyser, arteries and veins
Rush divider measurement end and be connected to oscillograph, also including the Rogowski coil for being serially connected in backflow pole, Rogowski coil is connected to oscillograph,
Oscillograph is used for the surge voltage and current waveform for measuring grounding body.
2. a kind of portable impact current feedback circuit measured for impulse earthed resistance according to claim 1, it is special
Levy and be：Main circuit includes AC AC powers, pressure regulator T1, rectification silicon stack D1, charging resistor R1, electric capacity of voltage regulation C1, high-frequency inversion
Bridge, step-up transformer T2, rectification silicon stack D2, charging resistor R2, divider, main capacitance C2, discharge switch S, wave regulating resistor R3
Pressure regulator T is connected to harmonic inductance L, AC ac power output1, pressure regulator T1Export one end concatenation rectification silicon stack D1With fill
Resistance R1, electric capacity of voltage regulation C1One end is connected to charging resistor R1, the other end is connected to pressure regulator T1The other end, electric capacity of voltage regulation C1It is defeated
Go out end and be parallel with high-frequency inversion bridge, high-frequency inversion bridging is connected to step-up transformer T2, step-up transformer T2Output is serially connected with one end
Rectification silicon stack D2With charging resistor R2, divider and main capacitance C2Two ends are connected respectively to charging resistor R after parallel connection2And liter
Pressure transformer T2Export the other end, main capacitance C2Positive pole is serially connected with discharge switch S, wave regulating resistor R3With harmonic inductance L, harmonic electricity
Sense is connected to the electric current injector of grounding body, and the current reflux pole of grounding body is connected to step-up transformer T2The other end, electric discharge is opened
Pass S is sphere gap switch, is acted by magnet control ball gap, and electromagnet is connected to control circuit, main capacitance C2Two ends, which are connected with, adopts
The sample circuit of collecting voltage, sample circuit includes divider and ADC change-over circuits, and sample circuit is connected to control circuit.
3. a kind of portable impact current feedback circuit measured for impulse earthed resistance according to claim 2, it is special
Levy and be：High-frequency inversion bridge is by transistor Q1, transistor Q2, transistor Q3, transistor Q4Bridge joint is formed, transistor Q1, transistor
Q2, transistor Q3With transistor Q4Use insulated gate bipolar transistor.
4. a kind of portable impact current feedback circuit measured for impulse earthed resistance according to claim 2, it is special
Levy and be：Divider is by high-voltage arm resistance R of the resistance for 50M Ω4With the low-voltage arm resistance R that resistance is 5k Ω5Concatenation and
Into.
5. a kind of portable impact current feedback circuit measured for impulse earthed resistance according to claim 2, it is special
Levy and be：Main capacitance C2For two pressure-resistant 30kV, 1uF impulse capacitor series connection, main capacitance C2Negative pole is grounded.
6. a kind of portable impact current feedback circuit measured for impulse earthed resistance according to claim 1, it is special
Levy and be：Circuit connection electromagnet, sample circuit, drive circuit and display circuit are controlled, electromagnet is used to control discharge switch,
Sample circuit is connected to control circuit, for main capacitance C2Both end voltage collection, drive circuit be used for high-frequency inversion bridge
Four transistors be driven.
7. a kind of portable impact current feedback circuit measured for impulse earthed resistance according to claim 1, it is special
Levy and be：Also include major loop case and control cabinet, control cabinet is connected in major loop case, major loop case by wire and optical fiber pacifies
Fill and control circuit and pressure regulator T are installed in main circuit, control cabinet1, control cabinet surface is provided with for showing main capacitance C2Charging electricity
The display screen of pressure, pressure regulator T1Voltage-regulation knob, control discharge switch and high-frequency inversion bridge trigger button, emergent stopping
Button and power supply indicator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621473075.2U CN206321711U (en) | 2016-12-30 | 2016-12-30 | A kind of portable impact current feedback circuit measured for impulse earthed resistance |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621473075.2U CN206321711U (en) | 2016-12-30 | 2016-12-30 | A kind of portable impact current feedback circuit measured for impulse earthed resistance |
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| Publication Number | Publication Date |
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| CN206321711U true CN206321711U (en) | 2017-07-11 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201621473075.2U Active CN206321711U (en) | 2016-12-30 | 2016-12-30 | A kind of portable impact current feedback circuit measured for impulse earthed resistance |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106526330A (en) * | 2016-12-30 | 2017-03-22 | 贵州电网有限责任公司电力科学研究院 | Portable impact current generator for measuring impact ground resistance |
| CN108761289A (en) * | 2018-06-07 | 2018-11-06 | 哈尔滨理工大学 | A kind of high density capacitors quality and Withstand test device |
-
2016
- 2016-12-30 CN CN201621473075.2U patent/CN206321711U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106526330A (en) * | 2016-12-30 | 2017-03-22 | 贵州电网有限责任公司电力科学研究院 | Portable impact current generator for measuring impact ground resistance |
| CN108761289A (en) * | 2018-06-07 | 2018-11-06 | 哈尔滨理工大学 | A kind of high density capacitors quality and Withstand test device |
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