CN203929828U - Prevent the protection syndeton that in variable-frequency power sources cabinet, element is impacted by test product flashover - Google Patents
Prevent the protection syndeton that in variable-frequency power sources cabinet, element is impacted by test product flashover Download PDFInfo
- Publication number
- CN203929828U CN203929828U CN201420356105.6U CN201420356105U CN203929828U CN 203929828 U CN203929828 U CN 203929828U CN 201420356105 U CN201420356105 U CN 201420356105U CN 203929828 U CN203929828 U CN 203929828U
- Authority
- CN
- China
- Prior art keywords
- variable
- frequency power
- power sources
- common port
- test product
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000012360 testing method Methods 0.000 title claims abstract description 44
- 238000010521 absorption reaction Methods 0.000 claims abstract description 10
- 238000004804 winding Methods 0.000 claims abstract description 7
- 230000001052 transient effect Effects 0.000 claims abstract description 6
- 230000001629 suppression Effects 0.000 claims abstract description 4
- 230000015556 catabolic process Effects 0.000 description 8
- 230000001681 protective effect Effects 0.000 description 6
- 238000000034 method Methods 0.000 description 5
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- 230000008859 change Effects 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 238000002955 isolation Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000013016 damping Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000001771 impaired effect Effects 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 229960001296 zinc oxide Drugs 0.000 description 2
- 239000011787 zinc oxide Substances 0.000 description 2
- 240000004859 Gamochaeta purpurea Species 0.000 description 1
- 229910018503 SF6 Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000010616 electrical installation Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000003116 impacting effect Effects 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000012946 outsourcing Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000005622 photoelectricity Effects 0.000 description 1
- 238000004382 potting Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- SFZCNBIFKDRMGX-UHFFFAOYSA-N sulfur hexafluoride Chemical compound FS(F)(F)(F)(F)F SFZCNBIFKDRMGX-UHFFFAOYSA-N 0.000 description 1
- 229960000909 sulfur hexafluoride Drugs 0.000 description 1
Abstract
A kind of protection syndeton that prevents that in variable-frequency power sources cabinet, element is impacted by test product flashover, it is characterized in that: by the high pressure resonant tank common port G1 (comprising exciting transformer high pressure tail and load capacitance earth terminal) in variable-frequency power sources cabinet inner looping, resonant tank time common port and protection common port G2 (comprise variable-frequency power sources cabinet shell, exciting transformer shell, body grounding end and voltage divider earth terminal), control loop common port G3 three is independent grounding respectively, variable-frequency power sources in variable-frequency power sources cabinet alternate and relatively between install respectively resistance-capacitance absorption device and lightning arrester additional, for absorbing, over-voltage suppression, the high pressure winding of exciting transformer installs lightning arrester additional, prevent that the transient overvoltage that test product punctures generation is coupled to low-pressure side.
Description
Technical field
The utility model relates to insulation of electrical installation detection technique field, is a kind of protection syndeton that prevents that in variable-frequency power sources cabinet, element is impacted by test product flashover specifically.
Background technology
Domestic high voltage electric equipment is because insulation margin is little, the quality good or not of manufacturing plant's starting material itself and outsourcing piece is uneven, the technology controlling and process of manufacture, assembling, fixing link is dispersed large, for ensureing the safe operation after high voltage electric equipment puts into operation, after high voltage electric equipment installs, need carry out Field AC Withstand Voltage Test, reliable with the device security of guaranteeing to put into operation.
For GIS (" Cubicle Gas-Insulated Switchgear ", refer to sulfur hexafluoride sealed combination electrical equipment) etc. the larger test specimen of electric capacity carry out AC voltage withstand test, need jumbo testing equipment, at this moment can adopt series resonance test device, loop is made up of reactor and the power supply of test specimen load capacitance and series connection with it.This method has the plurality of advantages such as volume is little, quality is light, required power supply capacity is little.And, puncture once test product, because circuit loses condition of resonance, electric power outputting current reduces automatically, and the voltage at test product two ends declines suddenly, can not produce superpotential, discharge energy is little, and the impact that therefore test specimen is subject to and infringement are very little.The method has become the on-the-spot effective method the most generally adopting.
But, in the time that series resonant equipment carries out AC voltage withstand test and test product generation flashover breakdown to certain test product, owing to not taking effective protection measure in variable-frequency power sources cabinet, often can there is variable-frequency power sources cabinet damage of internal device, even may jeopardize personal safety.
Conventionally; variable-frequency power sources cabinet has isolating transformer and MOA (Zinc-Oxide Arrester) to protect, still, and because the time is short; frequency is high, and isolation becomes that coupling and MOA lightning arrester may have little time response or instantaneous energy is excessive and cause the components and parts such as MOA lightning arrester to damage.
Summary of the invention
Technical problem to be solved in the utility model is thoroughly to solve variable-frequency power sources cabinet element impaired problem in the time being everlasting test product flashover breakdown; the safeguard measure that prevents that variable-frequency power sources cabinet inner member is impacted by test product flashover is provided, a kind of protection syndeton that prevents that in variable-frequency power sources cabinet, element is impacted by test product flashover is provided.
To achieve these goals, the technical solution adopted in the utility model is as follows:
The described protection syndeton that prevents that in variable-frequency power sources cabinet, element is impacted by test product flashover; it is characterized in that: the high pressure resonant tank common port G1 in variable-frequency power sources cabinet inner looping, resonant tank time common port G2 and protection common port G2, control loop common port G3 three are distinguished to independent grounding; wherein said high pressure resonant tank common port G1 comprises high pressure tail and the load capacitance earth terminal of exciting transformer, and described resonant tank time common port G2 comprises the shell of variable-frequency power sources cabinet, shell, body grounding end and the voltage divider earth terminal of exciting transformer.
Further, the variable-frequency power sources in described variable-frequency power sources cabinet alternate and relatively between install respectively resistance-capacitance absorption device and MOA lightning arrester additional, for absorbing, over-voltage suppression.
Further, the high pressure winding of described exciting transformer installs MOA lightning arrester additional, prevents that the transient overvoltage that test product punctures generation is coupled to low-pressure side.
For variable-frequency power sources cabinet element impaired problem when the test product flashover breakdown, through studying targetedly discovery, conventionally test product is always breakdown at positive peak or the negative peak place of alternating voltage, puncture instantaneous voltage and drop into zero time t conventionally between 0.1-10us, electric voltage frequency f=10M-100kHz now, even when electric discharge, the test product of being with (containing voltage divider) electric capacity C only has 0.002uF (in fact test product capacity is much larger than this value), puncture the instantaneous electric current I=U*2 π * f*C=750kV*2*3.142*f*C that flows through point of discharge and loop, in formula, U, f, C represents respectively voltage breakdown, containing the test product electric capacity of voltage divider, flashover voltage frequency, in the time of f=10MHz, I ≈ 100kA, in the time of f=100kHz, I ≈ 1kA.Visible, because du/dt is very large, puncturing the instantaneous electric current that flows through point of discharge and loop is kilo-ampere level.
Ground connection copper cash area is about 16mm
2, stretching and around without permeability magnetic material in the situation that, its stray inductance, in uH level, is about 0.1-1uH/m conventionally at copper cash, the about 0.1m Ω of resistance, if surrounding environment is severe and bare copper wire has discounting phenomenon, inductance will be increased to 10uH-100uH/m.
If electric voltage frequency f is 100kHz when electric discharge, it is 1uH that ground wire is posted body inductance L, and discharge current I is 1000A, calculates ground wire and posts π fL=2 × 3.14 × 100 × 10, body inductive reactance xl=2
3× 10
-6=0.628 Ω, issuable superpotential U on every meter line
d=I × XL=1000 × 0.628=628V, with 30 meter line computations, U
d=30 × 628=12560V, the body inductance of posting of ground wire has increased slightly, and this value also can increase.
As can be seen here, in the time of test product flashover breakdown, the large electric current of instantaneous short circuit flows through and causes ground wire and earth point current potential to be elevated, because earthing mode is one point earth, in the time that flashover occurs, the all ground connection position current potential that shares same earth point is all elevated, and causes the current potential moment of auxiliary equipment or variable-frequency power sources cabinet internal circuit to change, and then causes damage of internal device.Simultaneously; potential difference (PD) moment between power supply and earth potential also can change; although the existing isolating transformer of variable-frequency power sources cabinet and MOA lightning arrester are protected; but; because the time is short; frequency is high, and isolation becomes that coupling and MOA lightning arrester may have little time response or instantaneous energy is excessive and cause the components and parts such as MOA lightning arrester to damage.
The utility model has passed through concrete careful further investigation in infringement flashover being occurred and cause; in high-potting process; if associated components is not all given to the safeguard measure for anti-flashover breakdown, the voltage of protective ground when test product punctures, resonant tank time earth point is along with the voltage of high pressure resonant tank earth point is raised and is a reason that causes damage to go beyond by instantaneous raising.Because earthing mode is one point earth, all ground connection position current potential that shares same earth point is all elevated, and causes the current potential moment of auxiliary equipment or variable-frequency power sources cabinet internal circuit to change, and then causes damage of internal device.
Separate by working earthing and protective ground, prevent that the voltage of protective ground when test product punctures, resonant tank time earth point is along with the voltage of high pressure resonant tank earth point is raised and raised by instantaneous, fundamentally solved flashover and cause the principal element of damage.Alternate by power supply, relatively install respectively resistance-capacitance absorption device (R-C series circuit) additional, effectively absorb at line-internal, over-voltage suppression, eliminate the detrimental effect that most of peak voltage causes; By installing lightning arrester additional at exciting transformer high pressure winding, prevent that the transient overvoltage that test product punctures generation is coupled to low-pressure side.These safeguard measures can prevent that variable-frequency power sources cabinet inner member is impacted by test product flashover very effectively.
Use this programme as the protection for impacted by test product flashover; reliability is high; employing measure is simple, quick, effective, and the safeguard measure that impacted by test product flashover for high-pressure frequency-conversion cabinet inner member provides new reliable and simple and easy to do measure.
Brief description of the drawings
Fig. 1 is the circuit theory diagrams that employing series resonant equipment carries out Field AC Withstand Voltage Test,
Fig. 2 is circuit theory schematic diagram of the present utility model.
In figure: 1-variable-frequency power sources cabinet, 2-control circuit, 3-high-voltage measuring circuit, 4-frequency conversion major loop, 5-exciting transformer, 6-resonant tank, 7-voltage divider, 8-load capacitance, 9-MOA lightning arrester.
Embodiment
Below in conjunction with accompanying drawing, the utility model is further illustrated: as shown in Figure 1, the circuit structure that adopts series resonant equipment to carry out Field AC Withstand Voltage Test is: three-phase supply input variable-frequency power sources cabinet 1,1 output of variable-frequency power sources cabinet connects exciting transformer 5 input ends, exciting transformer 5 output terminals connect L-C resonant tank, L is current-limiting reactor, and C is load capacitance 8 and voltage divider 7 Capacitance parallel connections; As shown in embodiment in Fig. 2, power supply is by mains-supplied, between three-phase power line, connect respectively resistance-capacitance absorption device, three-phase supply to G2 access MOA lightning arrester, the main circuit of frequency converter 4 of power lead access variable-frequency power sources cabinet 1, the output of main circuit of frequency converter 4 is connected to resonant tank 6 by exciting transformer 5, and resonant tank 6 accesses common port G2 by voltage divider 7, and receives common port G1 by load capacitance 8.The high pressure tail of exciting transformer and load capacitance earth terminal are connected to high pressure resonant tank common port G1, the shell of variable-frequency power sources cabinet 1, the shell of exciting transformer 5, body grounding end and voltage divider 7 earth terminals are connected to resonant tank time common port G2, and the control loop common port of the control circuit 2 in variable-frequency power sources cabinet 1 connects G3.The car body of on-board testing equipment becomes a part for equipment, and now body grounding end is connected to G2.
During in view of test product disruptive discharge, often damage auxiliary equipment or variable-frequency power sources cabinet, carried out the optimal design of three aspects:.
(1) high pressure resonance common port is separated with resonant tank time common port, protective grounding
In Fig. 2, G1 is high pressure resonant tank common port, i.e. the high pressure tail of exciting transformer 5 and load capacitance 8 ground connection, and this ground connection should adopt larger cross-section ground wire, between G1 and variable-frequency power sources cabinet 1, is isolated by exciting transformer 5 windings; G2 is protection common port and resonant tank time common port, and variable-frequency power sources cabinet shell, excitation become shell, body grounding end and voltage divider earth terminal (comprise and become metering circuit 3 earth terminals in cabinet power cabinet); G3 is control loop common port, and G3 and G2 adopt photoelectricity isolation.
Because native system is at high pressure over the ground when disruptive discharge, generally all can occur in load capacitance 8 one sides, flow into the earth with the large electric current of instantaneous short-circuit by ground wire, current potential moment is by corresponding lifting near the earth and on ground wire, the ground wire and the earth point current potential moment that are G1 are lifted, and as G1 and G2 do not distinguish, connect the current potential lifting together of the circuit of G2, can make like this G2 internal circuit current potential moment change, and then damage the device in the circuit that connects G2.Therefore, working earthing and protective ground need be separated, G1 and G2 adopt difference access the earth.
(2) power supply alternate, install respectively resistance-capacitance absorption device and lightning arrester additional between relatively
For preventing that internal system transient overvoltage from impacting the switching overvoltage of generation (be mainly isolating switch, contactor cut-off) damage to important electrical, current way is near isolating switch or MOA lightning arrester 9 is installed in contactor position or resistance-capacitance absorption device carries out surge protection.The relatively advantage in two series products performances, the advantage of zinc oxide product is mainly strong in energy absorption capability, can be for heavy current impacts such as thunder-lightnings; The advantage of resistance-capacitance absorption device is mainly that onset voltage is low, can effectively absorb the impact of little rush of current on equipment.
In the time of test product flashover breakdown, variable-frequency power sources cabinet current potential moment alternate and relatively changes, and occurs superpotential, though the lightning arrester of installing between relatively can effectively absorb relatively superpotential, does not have alternate superpotential protective effect.And at the alternate resistance-capacitance absorption device that installs additional of power supply, it is R-C series circuit, electric capacity is for absorbing high-frequency signal, resistance is for damping, moment vibration and the high-frequency current that can effectively suppress switching overvoltage, slow down superpotential waveform, and steepness and amplitude reduce, add the damping action of resistance, the higher-order of oscillation is decayed rapidly.
(3) exciting transformer high pressure winding installs MOA lightning arrester additional
Because native system is at high pressure over the ground when disruptive discharge, generally all can occur in load capacitance side, by installing MOA lightning arrester 9 additional at exciting transformer high pressure winding, prevent that the transient overvoltage that high-pressure side test product punctures generation is coupled to low-pressure side and damages auxiliary equipment or variable-frequency power sources cabinet internal component.
Claims (3)
1. a protection syndeton that prevents that in variable-frequency power sources cabinet, element is impacted by test product flashover, it is characterized in that: by the high pressure resonant tank common port G1 in variable-frequency power sources cabinet inner looping, resonant tank time common port G2 and protection common port G2, control loop common port G3 three is independent grounding respectively, wherein said high pressure resonant tank common port G1 comprises high pressure tail and load capacitance (8) earth terminal of exciting transformer (5), described resonant tank time common port G2 comprises the shell of variable-frequency power sources cabinet (1), the shell of exciting transformer (5), body grounding end and voltage divider (7) earth terminal.
2. the protection syndeton that prevents that in variable-frequency power sources cabinet, element is impacted by test product flashover according to claim 1; it is characterized in that: the variable-frequency power sources in described variable-frequency power sources cabinet alternate and relatively between install respectively resistance-capacitance absorption device and MOA lightning arrester additional, for absorbing, over-voltage suppression.
3. the protection syndeton that prevents that in variable-frequency power sources cabinet, element is impacted by test product flashover according to claim 1; it is characterized in that: the high pressure winding of described exciting transformer installs MOA lightning arrester additional, prevent that the transient overvoltage that test product punctures generation is coupled to low-pressure side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420356105.6U CN203929828U (en) | 2014-06-30 | 2014-06-30 | Prevent the protection syndeton that in variable-frequency power sources cabinet, element is impacted by test product flashover |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420356105.6U CN203929828U (en) | 2014-06-30 | 2014-06-30 | Prevent the protection syndeton that in variable-frequency power sources cabinet, element is impacted by test product flashover |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203929828U true CN203929828U (en) | 2014-11-05 |
Family
ID=51825626
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420356105.6U Active CN203929828U (en) | 2014-06-30 | 2014-06-30 | Prevent the protection syndeton that in variable-frequency power sources cabinet, element is impacted by test product flashover |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203929828U (en) |
-
2014
- 2014-06-30 CN CN201420356105.6U patent/CN203929828U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104111412B (en) | The protection attachment structure for preventing variable-frequency power sources cabinet interior element from being impacted by test product flashover | |
| CN105356441A (en) | Intelligent PT harmonic elimination and phase selection method and device | |
| CN203519768U (en) | Traveling-wave signal extraction equipment and system for single-phase earth fault | |
| CN105449651A (en) | Controllable resonance suppression device for distribution network | |
| CN108923342B (en) | GIS outlet sleeve with damping function | |
| CN104518506A (en) | Arc suppresser allowing distinguishing of intra-station arc grounding, extra-station grounding and motor stator arc grounding | |
| Mueller et al. | Switching phenomena in medium voltage systems-good engineering practice on the application of vacuum circuit-breakers and contactors | |
| CN201868869U (en) | Combined type large-capacity self-separating overvoltage protector | |
| CN203929828U (en) | Prevent the protection syndeton that in variable-frequency power sources cabinet, element is impacted by test product flashover | |
| CN102195266A (en) | Series resonant-type fault current limiter | |
| CN106684850B (en) | High-tension transformer earth neutral system | |
| CN105098757A (en) | Method for eliminating resonance of power distribution station | |
| CN209056928U (en) | Surge protective device and its test macro | |
| CN202997580U (en) | Silicon controlled rectifier RC protection loop in TSC apparatus | |
| CN202424146U (en) | Ferroresonance-resistant control circuit of voltage transformer | |
| CN106129994A (en) | A kind of novel efficient extinguishing arc and overvoltage protection | |
| CN202696141U (en) | Arc-extinction resonance-elimination device | |
| CN201388042Y (en) | Central high-voltage switch equal-height cabinet | |
| CN201118228Y (en) | Combination type resistance-capacity protector capable of freely switching | |
| CN110165646A (en) | A kind of cable shield electric current bleeder | |
| CN203119468U (en) | Three-phase combined overvoltage protector | |
| CN104134984A (en) | Neutral point virtual ground connection cabinet | |
| CN105223479B (en) | A kind of extra-high voltage GIS testing on-site impact transient overvoltage suppressing method | |
| CN220273320U (en) | Resistance-capacitance overvoltage protector | |
| CN201388009Y (en) | Central isolated handcart type arc extinction, harmonic elimination and route selection device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |