CN109324306A - A kind of GIS device current transformer error test macro and its construction method - Google Patents
A kind of GIS device current transformer error test macro and its construction method Download PDFInfo
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- CN109324306A CN109324306A CN201811532003.4A CN201811532003A CN109324306A CN 109324306 A CN109324306 A CN 109324306A CN 201811532003 A CN201811532003 A CN 201811532003A CN 109324306 A CN109324306 A CN 109324306A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
- G01R35/02—Testing or calibrating of apparatus covered by the other groups of this subclass of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating
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Abstract
The invention discloses a kind of site error test macros of GIS device current transformer, including current lifting device, standard current transformer, it is tested current transformer (CT) and error testing equipment, conducting wire both ends in High-current output circuit of current lifting device are respectively connected to earthing switch (ES1, ES2) close to the grounded metal sheet of ground terminal side, earthing switch (ES1, ES2) it is in closed state, make to be tested current transformer (CT) concatenation into High-current output circuit of current lifting device, error testing equipment is respectively connected to standard current transformer and is tested the secondary output end of current transformer (CT).The system constituting method greatly improves the site error verifying work efficiency of current transformer in GIS, and labor intensity significantly reduces, and under the experimental condition for meeting regulatory requirements, reduces the capacity of experiment power supply and the pressure of testing equipment transport.
Description
Technical field
The invention belongs to power generations, power supply technique field, and in particular to a kind of scene mistake of GIS device current transformer
Poor test macro and its construction method.
Background technique
With the construction of China's power grid, Cubicle Gas-Insulated Switchgear (hereinafter referred to as GIS) takes up an area face due to it
The features such as product small, high reliablity, it is widely used in 110kV and the above substation.Wherein current transformer play current transformation and
The effect of electrical isolation can be converted to numerical value biggish primary current the lesser secondary current of numerical value, for protecting, measuring
Etc. purposes.Current mutual inductor on site error testing is the forcible inspection of item of National Technical regulatory requirements, and GIS current transformer is due to envelope
It closes in insulation gas chamber, bus is not exposed, and there are primary current circuit is long, ground capacitance is with duct length and switchgear number
The unfavorable factors such as variation are measured, so that the up-flow and boosting in transformer error test are more difficult, and the current country is in this side
The difficult point of face test.
The site error test basic principle of current transformer is as shown in Figure 1.Carry out current mutual inductor on site error testing
When, by the continuously adjustable power supply of pressure regulator output to current lifting device, current lifting device realizes a High-current output circuit, normalized current
The first siding ring of mutual inductor and subject current transformer is wrapped on High-current output circuit of current lifting device, is surveyed using error
Examination equipment is separately connected standard current transformer and subject current transformer, counts to two Current Transformer Secondary output valves
It calculates, calculates the precision of secondary output valve of the subject current transformer compared with standard current transformer.
The primary structure of current transformer is as shown in Figure 2 in GIS device.It is typical double-bus structure in Fig. 2, main transformer is logical
It crosses disconnecting switch DS1, DS2, DS3 and breaker CB1 is connected to bus I and II.Between disconnecting switch DS1 and breaker CB1
It is the Current Transmit 1 for monitoring main transformer operation power.ES1, ES2, ES3 of main transformer inlet wire branch are distributed across different positions
The grounding switch set.Wherein the Current Transmit 1 of main transformer inlet wire is the equipment for needing to carry out site error test.Carry out scene
When error testing, traditional method is to be led in the conducting wire link position access test of main transformer high-pressure side magnetosheath with high current
Line is then turned off all grounding switchs, is connected to magnetosheath and bus, and being connected to other one by bus has external interface
Route magnetosheath is formed primary big by a wire interface connecting test high current conducting wire of the magnetosheath of an other route
Current loop.An entire big current loop include two sections of GIS lines branch, one section of bus and with two sections of GIS routes
The identical test high current conducting wire of branch length, entire primary circuit length are not less than 20 meters.
When carrying out field test using the primary circuit of above method building, test is longer with high current conducting wire, scene examination
Perching is set time-consuming and laborious, and primary circuit is longer to cause impedance loop larger, and the up-flow equipment and experiment power supply capacity needed is larger,
Site layout project difficulty is larger.In addition, test current circuit of GIS pipeline is not intuitive, bus is not exposed, and primary test electricity
It flows back to and passes by the factors such as long no small difficulty all is brought to the site error test of current transformer, and domestic at present carry out
The common problem that GIS current mutual inductor on site error testing faces.
Summary of the invention
The characteristics of according to a large amount of field test and combining GIS device, the invention proposes a kind of GIS device Current Mutual Inductances
The site error test macro and its construction method of device.
The site error test macro technical solution of GIS device current transformer of the invention is as follows:
A kind of site error test macro of GIS device current transformer, including current lifting device, standard current transformer, quilt
Current Transmit and error testing equipment are tried, current lifting device realizes a High-current output circuit, standard current transformer
First siding ring is wrapped on High-current output circuit of current lifting device, and the subject Current Transmit setting in GIS device exists
Between main transformer magnetosheath and bus, main transformer magnetosheath is connected to bus by the first disconnecting switch DS1, is tested the two of Current Transmit
End is respectively equipped with earthing switch ES1, ES2, it is characterised in that: a conducting wire both ends in High-current output circuit of current lifting device point
It is not connected to earthing switch ES1, ES2 close to the grounded metal sheet of ground terminal side, earthing switch ES1, ES2 are in closed state,
Concatenate subject Current Transmit into High-current output circuit of current lifting device, error testing equipment is respectively connected to standard
The secondary output end of current transformer and subject Current Transmit.
Further, it is tested between Current Transmit and bus and is provided with breaker CB1.
Further, bus includes the first bus and the second bus.
Further, second and third disconnecting switch DS2, DS3, the second isolation are provided between breaker CB1 and bus
Switch DS2 is connected to the first bus, and third disconnecting switch DS3 is connected to the second bus.
Further, the second disconnecting switch is connected in parallel with third disconnecting switch.
Further, the first disconnecting switch DS1, subject Current Transmit, breaker CB1 connect to form main transformer inlet wire master
Road.
Further, earthing switch ES1, ES2 forms main transformer inlet wire branch.
Site error test macro construction method technical solution of the invention is as follows:
A kind of construction method of the site error test macro of GIS device current transformer, it is characterised in that including following
Step:
(1) current lifting device, standard current transformer, subject Current Transmit and error testing equipment, current lifting device are provided
It realizes a High-current output circuit, the first siding ring of standard current transformer is wrapped in High-current output of current lifting device
On circuit；
(2) the subject Current Transmit in GIS device is arranged between main transformer magnetosheath and bus, main transformer magnetosheath passes through
First disconnecting switch DS1 is connected to bus, and earthing switch ES1, ES2 is respectively set at the both ends of subject Current Transmit；
(3) closed ground switch ES1, ES2, the grounded metal sheet by earthing switch ES1, ES2 close to ground terminal side are opened,
Conducting wire both ends in High-current output circuit of current lifting device are respectively connected to the ground connection gold of the opening of earthing switch ES1, ES2
Belong to piece, concatenates subject Current Transmit into High-current output circuit of current lifting device；
(4) error testing equipment is respectively connected to standard current transformer and is tested the secondary output of Current Transmit
End.
Further, it is tested between Current Transmit and bus and is provided with breaker CB1, in building site error test
When system, it is closed breaker CB1.
Further, bus includes the first bus and the second bus.
Further, second and third disconnecting switch DS2, DS3, the second isolation are provided between breaker CB1 and bus
Switch DS2 is connected to the first bus, and third disconnecting switch DS3 is connected to the second bus.When constructing site error test macro,
Disconnect first, second, and third disconnecting switch DS1, DS2, DS3.
Further, the second disconnecting switch and third disconnecting switch are connected in parallel.
Further, the first disconnecting switch DS1, subject Current Transmit, breaker CB1 are connected in series, to be formed
Main transformer inlet wire main road.
Further, main transformer inlet wire branch is set by earthing switch ES1, ES2.
Site error test macro construction method of the invention can solve bus existing for traditional error testing method and
The too long technical problem of conductor length greatly reduces the bus length turned back and magnetosheath inlet to earthing switch
The distance at place, a bus length for participating in up-flow can reduce within 5 meters, substantially reduce the capacity of up-flow equipment.This method
Greatly improve the site error verifying work efficiency of current transformer in GIS, labor intensity significantly reduces, and wants meeting regulation
Under the experimental condition asked, the capacity of experiment power supply and the pressure of testing equipment transport are reduced.
Detailed description of the invention
Fig. 1 is that the site error of current transformer tests basic schematic diagram；
Fig. 2 is the primary structure schematic diagram of current transformer in GIS device；
Fig. 3 is the wiring schematic diagram of the site error test macro of GIS device current transformer of the present invention.
Specific embodiment
Specific embodiments of the present invention are described in detail below in conjunction with technical solution and attached drawing.
The site error test macro of the GIS device current transformer of the embodiment of the present invention, as shown in Figure 1, including up-flow
Device, standard current transformer, subject Current Transmit and error testing equipment, current lifting device realize that a High-current output returns
Road, the first siding ring of standard current transformer are wrapped on High-current output circuit of current lifting device, error testing equipment point
It is not connected to standard current transformer and is tested the secondary output end of Current Transmit.
As shown in figure 3, the subject Current Transmit in GIS device is arranged between main transformer magnetosheath and bus, main transformer magnetic
Set by the first disconnecting switch DS1 is connected to bus, be tested Current Transmit both ends be respectively equipped with earthing switch ES1,
A conducting wire both ends of ES2, High-current output circuit of current lifting device are respectively connected to earthing switch ES1, ES2 close to ground terminal one
The grounded metal sheet of side, earthing switch ES1, ES2 are in closed state, concatenate subject Current Transmit primary to current lifting device
In High-current output circuit.
Breaker CB1 is provided between subject Current Transmit and bus.Bus includes the first bus and the second bus.
Second and third disconnecting switch DS2, DS3 are provided between breaker CB1 and bus, the second disconnecting switch DS2 is connected to first
Bus, third disconnecting switch DS3 are connected to the second bus.Second disconnecting switch is connected in parallel with third disconnecting switch.First every
Pass DS1, subject Current Transmit, breaker CB1 is left to connect to form main transformer inlet wire main road.Earthing switch ES1, ES2 are formed
Main transformer inlet wire branch.
The site error test macro of the GIS device current transformer of the embodiment of the present invention is introduced referring to Fig. 1 and Fig. 3
Construction method, comprising the following steps:
(1) current lifting device, standard current transformer, subject Current Transmit and error testing equipment, current lifting device are provided
It realizes a High-current output circuit, the first siding ring of standard current transformer is wrapped in High-current output of current lifting device
On circuit；
(2) the subject Current Transmit in GIS device is arranged between main transformer magnetosheath and bus, main transformer magnetosheath passes through
First disconnecting switch DS1 is connected to bus, and earthing switch ES1, ES2 is respectively set at the both ends of subject Current Transmit；
(3) closed ground switch ES1, ES2, the grounded metal sheet by earthing switch ES1, ES2 close to ground terminal side are opened,
Conducting wire both ends in High-current output circuit of current lifting device are respectively connected to the ground connection gold of the opening of earthing switch ES1, ES2
Belong to piece, concatenates subject Current Transmit into High-current output circuit of current lifting device；
(4) error testing equipment is respectively connected to standard current transformer and is tested the secondary output of Current Transmit
End.
It is provided with breaker CB1 between subject Current Transmit and bus, when constructing site error test macro, is closed
Close breaker CB1.Bus includes the first bus and the second bus.Second and third are provided between breaker CB1 and bus
Disconnecting switch DS2, DS3, the second disconnecting switch DS2 are connected to the first bus, and third disconnecting switch DS3 is connected to the second bus.
When constructing site error test macro, first, second, and third disconnecting switch DS1, DS2, DS3 is disconnected.Second is kept apart
Pass is connected in parallel with third disconnecting switch.First disconnecting switch DS1, subject Current Transmit, breaker CB1 series connection are connected
It connects, to form main transformer inlet wire main road.Main transformer inlet wire branch is set by earthing switch ES1, ES2.
It is tested such access way of current transformer, the bus length turned back can be greatly reduced and magnetosheath enters
To distance at earthing switch ES1 at mouthful, a bus length for participating in up-flow can reduce within 5 meters, substantially reduce up-flow and set
Standby capacity.
Applicant combines Figure of description to be described in detail and describe the embodiment of the present invention, but this field skill
Art personnel are it should be understood that above embodiments are only the preferred embodiments of the invention, and explanation is intended merely to help reader in detail
More fully understand spirit of that invention, and it is not intended to limit the protection scope of the present invention, on the contrary, any based on invention essence of the invention
Any improvement or modification made by mind should all be fallen within the scope and spirit of the invention.
Claims (14)
1. a kind of site error test macro of GIS device current transformer, including current lifting device, standard current transformer, subject
Current transformer (CT) and error testing equipment, current lifting device realize a High-current output circuit, standard current transformer
First siding ring is wrapped on High-current output circuit of current lifting device, subject current transformer (CT) setting in GIS device
Between main transformer magnetosheath and bus, main transformer magnetosheath is connected to bus by the first disconnecting switch (DS1), is tested current transformer
(CT) both ends are respectively equipped with earthing switch (ES1, ES2), it is characterised in that:
Conducting wire both ends in High-current output circuit of current lifting device are respectively connected to earthing switch (ES1, ES2) close to ground terminal
The grounded metal sheet of side, earthing switch (ES1, ES2) are in closed state, make to be tested current transformer (CT) concatenation to up-flow
In High-current output circuit of device, error testing equipment is respectively connected to standard current transformer and subject current transformer
(CT) secondary output end.
2. site error test macro according to claim 1, which is characterized in that subject current transformer (CT) and bus
Between be provided with breaker (CB1).
3. site error test macro according to claim 2, which is characterized in that bus includes that the first bus and second are female
Line.
4. site error test macro according to claim 3, which is characterized in that set between breaker (CB1) and bus
It is equipped with second and third disconnecting switch (DS2, DS3), the second disconnecting switch (DS2) is connected to the first bus, third disconnecting switch
(DS3) it is connected to the second bus.
5. site error test macro according to claim 4, which is characterized in that the second disconnecting switch is kept apart with third
Pass is connected in parallel.
6. site error test macro according to claim 2, which is characterized in that the first disconnecting switch (DS1), subject electricity
Current transformer (CT), breaker (CB1) series connection form main transformer inlet wire main road.
7. site error test macro according to claim 1, which is characterized in that earthing switch (ES1, ES2) forms master
Become inlet wire branch.
8. a kind of construction method of the site error test macro of GIS device current transformer, it is characterised in that including following step
It is rapid:
(1) current lifting device, standard current transformer, subject current transformer (CT) and error testing equipment are provided, current lifting device is real
The first siding ring of standard current transformer is wrapped in High-current output of current lifting device and returned by an existing High-current output circuit
On the road；
(2) the subject current transformer (CT) in GIS device is arranged between main transformer magnetosheath and bus, main transformer magnetosheath passes through the
One disconnecting switch (DS1) is connected to bus, subject current transformer (CT) both ends be respectively set earthing switch (ES1,
ES2)；
(3) closed ground switch (ES1, ES2), the grounded metal sheet by earthing switch (ES1, ES2) close to ground terminal side are opened,
Conducting wire both ends in High-current output circuit of current lifting device are respectively connected to the ground connection of the opening of earthing switch (ES1, ES2)
Sheet metal makes to be tested current transformer (CT) concatenation into High-current output circuit of current lifting device；
(4) error testing equipment is respectively connected to standard current transformer and is tested the secondary output of current transformer (CT)
End.
9. site error test macro construction method according to claim 8, which is characterized in that subject current transformer
(CT) it is provided with breaker (CB1) between bus, when constructing site error test macro, is closed the breaker (CB1).
10. site error test macro construction method according to claim 9, which is characterized in that bus includes first female
Line and the second bus.
11. site error test macro construction method according to claim 10, which is characterized in that breaker (CB1) with
Second and third disconnecting switch (DS2, DS3) are provided between bus, the second disconnecting switch (DS2) is connected to the first bus, the
Three disconnecting switch (DS3) are connected to the second bus, when constructing site error test macro, disconnect first, second, and third every
Leave pass (DS1, DS2, DS3).
12. site error test macro construction method according to claim 11, which is characterized in that by the second disconnecting switch
It is connected in parallel with third disconnecting switch.
13. site error test macro construction method according to claim 9, which is characterized in that by the first disconnecting switch
(DS1), it is tested current transformer (CT), breaker (CB1) series connection, to form main transformer inlet wire main road.
14. site error test macro construction method according to claim 8, which is characterized in that by earthing switch (ES1,
ES2) it is set as main transformer inlet wire branch.
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| CN201811532003.4A CN109324306B (en) | 2018-12-14 | 2018-12-14 | GIS equipment current transformer error testing system and construction method thereof |
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|---|---|---|---|
| CN201811532003.4A CN109324306B (en) | 2018-12-14 | 2018-12-14 | GIS equipment current transformer error testing system and construction method thereof |
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| CN109324306B CN109324306B (en) | 2021-11-23 |
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| CN111123050A (en) * | 2019-12-31 | 2020-05-08 | 中国能源建设集团华东电力试验研究院有限公司 | Transformer partial discharge test of transformer and GIS in GIL connection mode |
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