CN207198234U - A kind of isolated neutral capacitance current of distribution network measurement apparatus - Google Patents
A kind of isolated neutral capacitance current of distribution network measurement apparatus Download PDFInfo
- Publication number
- CN207198234U CN207198234U CN201721308787.3U CN201721308787U CN207198234U CN 207198234 U CN207198234 U CN 207198234U CN 201721308787 U CN201721308787 U CN 201721308787U CN 207198234 U CN207198234 U CN 207198234U
- Authority
- CN
- China
- Prior art keywords
- module
- distribution network
- isolated neutral
- measurement apparatus
- capacitance current
- 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
Abstract
The utility model discloses a kind of isolated neutral capacitance current of distribution network measurement apparatus, including CPU module, and it is used for the data signal for producing certain frequency, and is converted into simulation constant current signal through D/A modular converters and is sent to signal transmitting and amplification module；Transmitting is to first voltage transformer after the simulation constant current signal amplification that the signal transmitting and amplification module are used to receive, the open delta wiring injection power distribution network through first voltage transformer；And current signal collection module, it is used for the current signal for gathering injection power distribution network；And second voltage transformer, it is connected with power distribution network, for gathering the power distribution network return voltage signal of Injection Current signal；And current signal collection module and second voltage transformer pass sequentially through filtration module and A/D modular converters are connected with CPU module, isolated neutral capacitance current of distribution network measured value is exported by CPU module.The utility model can accurately measure isolated neutral capacitance current of distribution network.
Description
Technical field
The utility model belongs to field of current measurement, more particularly to a kind of measurement of isolated neutral capacitance current of distribution network
Device.
Background technology
With cable run, proportion is continuously increased in power system, and power distribution network ground capacity electric current gradually increases, in
Property point earth-free power distribution network when there is earth fault electric arc be difficult to extinguish, and easily develop into phase-to phase fault, jeopardize the person and equipment
Safety.Distribution network earth insulation parameter directly affects power distribution network zero sequence overvoltage and ground-fault arc capacity for quenching.
Capacitance current of distribution network traditional measurement method is broadly divided into direct method and indirect method.Wherein, direct method mainly includes
Single Phase Metal is grounded method, this method complex operation, potential safety hazard be present, does not use typically.Indirect method is general additional on the line
One electric capacity, the change by measuring voltage calculate capacitance current value indirectly, and this method measurement time is longer, and need pair
One time side apparatus is operated.
With the development of technique of computer measurement and control, a series of capacitance current On-line Measuring Method is proposed both at home and abroad：From
Arc suppression coil voltage transformer secondary surveys injection resonant frequency signal measurement capacitance current, and measurement accuracy is high, but this method is uncomfortable
Power distribution network is grounded for isolated neutral power distribution network and through arc suppression coil with mode.The measurement letter of isolated neutral power distribution network
Number need to inject from common voltage transformer secondary side, common voltage transformer internal impedance is much larger than in arc suppression coil or reactor
The internal impedance of portion's voltage transformer, influence the precision of Injection Signal measurement parameter, it is impossible to be ignored.Domestic existing neutral point is not
Power distribution network injection constant frequency signal measurement capacitance current method is grounded, it does not account for the influence of voltage transformer internal impedance,
Measurement error is big.
In summary, need badly it is a kind of can accurate measurement isolated neutral capacitance current of distribution network device.
Utility model content
In order to solve the deficiencies in the prior art, the utility model provides a kind of isolated neutral capacitance current of distribution network
Measurement apparatus, it can accurately measure isolated neutral capacitance current of distribution network.
A kind of isolated neutral capacitance current of distribution network measurement apparatus of the present utility model, including：
CPU module, it is used for the data signal for producing certain frequency, and is converted into simulation constant current letter through D/A modular converters
Number it is sent to signal transmitting and amplification module；The signal transmitting and amplification module are used to put the simulation constant current signal received
Transmitting is to first voltage transformer after big, the open delta wiring injection power distribution network through first voltage transformer；And
Current signal collection module, it is used for the current signal for gathering injection power distribution network；And
Second voltage transformer, it is connected with power distribution network, and the power distribution network return voltage for gathering Injection Current signal is believed
Number；And
The current signal collection module and second voltage transformer pass sequentially through filtration module and A/D modular converters with
CPU module is connected, and isolated neutral capacitance current of distribution network measured value is exported by CPU module.
Further, the output end of filtration module is also connected with FPGA module, and the FPGA module is connected with CPU module.
Further, the CPU module is also connected with high in the clouds memory module.
Further, the CPU module is also connected with communication module, the communication module and remote monitoring server phase
Even.
Further, the communication module is wireless communication module or wire cable.
Further, the wireless communication module is Wifi modules or Zigbee module.
Further, the CPU module is also connected with human-computer interaction module.
Further, the human-computer interaction module includes touch-screen and keyboard.
Further, the filtration module is active power filtering module.
Further, the filtration module is RC active filters.
Compared with prior art, the beneficial effects of the utility model are：
(1) a kind of isolated neutral capacitance current of distribution network measurement apparatus of the present utility model, varies without power distribution network
Primary connection, power distribution network normal operation is not influenceed, ensured that measurement process is safe and reliable；
(2) a kind of isolated neutral capacitance current of distribution network measurement apparatus provided by the utility model, can accurately be surveyed
Measure isolated neutral capacitance current of distribution network；
(3) device of the present utility model eliminates the influence of voltage transformer internal impedance, and parameter measurement precision is high；
(4) post-set arc suppression coils do not put into operation in power distribution network normal operation, equivalent to ungrounded electric net work, therefore,
The device of the present utility model is equally applicable to be grounded power distribution network through post-set arc suppression coils.
Brief description of the drawings
The Figure of description for forming the part of the application is used for providing further understanding of the present application, and the application's shows
Meaning property embodiment and its illustrate be used for explain the application, do not form the improper restriction to the application.
Fig. 1 is the structural representation of embodiment one of isolated neutral capacitance current of distribution network measurement apparatus of the present utility model
Figure；
Fig. 2 is the structural representation of embodiment two of isolated neutral capacitance current of distribution network measurement apparatus of the present utility model
Figure.
Embodiment
It is noted that described further below is all exemplary, it is intended to provides further instruction to the application.It is unless another
Indicate, all technologies used herein and scientific terminology are with usual with the application person of an ordinary skill in the technical field
The identical meanings of understanding.
It should be noted that term used herein above is merely to describe embodiment, and be not intended to restricted root
According to the illustrative embodiments of the application.As used herein, unless the context clearly indicates otherwise, otherwise singulative
It is also intended to include plural form, additionally, it should be understood that, when in this manual using term "comprising" and/or " bag
Include " when, it indicates existing characteristics, step, operation, device, component and/or combinations thereof.
Embodiment one
Fig. 1 is the structural representation of embodiment one of isolated neutral capacitance current of distribution network measurement apparatus of the present utility model
Figure.
As shown in figure 1, the isolated neutral capacitance current of distribution network measurement apparatus of the present embodiment, including：
CPU module 1, it is used for the data signal for producing certain frequency, and is converted into simulation constant current through D/A modular converters 2
Signal is sent to signal transmitting and amplification module 3；The signal transmitting and amplification module 3 are used to believe the simulation constant current received
Transmitting injects power distribution network to voltage transformer 7 through voltage transformer 7 after number amplification；And
Current signal collection module 9, it is used for the current signal for gathering injection power distribution network；And
Second voltage transformer 8, it is connected with power distribution network, and the power distribution network return voltage for gathering Injection Current signal is believed
Number；And
The current signal collection module 9 and second voltage transformer 8 pass sequentially through filtration module 4 and A/D moduluss of conversion
Block 5 is connected with CPU module 1, and 1 isolated neutral capacitance current of distribution network measured value is exported by CPU module.
In the present embodiment, CPU module 1 can use the processing of the processor chips or other models of Intel Company's production
Device chip is realized.
D/A modular converters 2, it can be realized using D/A conversion chips circuit.
Signal is launched and amplification module 3 is the integrated of signal transmitting chip circuit and amplifying circuit.
Current signal collection module 9 can be realized using current transformer.
A/D modular converters 5, it can be realized using A/D conversion chips circuit.
In the present embodiment, CPU module 1 is also connected with high in the clouds memory module 10.
Wherein, high in the clouds memory module 10 can use RAM or other extraneous storage devices, such as USB flash disk or SD card.
In the present embodiment, the CPU module 1 is also connected with communication module 11, the communication module 11 and remote monitoring
Server is connected.
Wherein, communication module 11 can be wireless communication module or wire cable.
Wireless communication module can be realized using Wifi modules or Zigbee module.
In the present embodiment, the CPU module 1 is also connected with human-computer interaction module 12.
Wherein, the human-computer interaction module 12 includes touch-screen and keyboard.
Touch-screen can use Eview-ET070 touch-screens.
In the present embodiment, the filtration module 4 is active power filtering module.
Wherein, the structure of active power filtering module can be realized using existing structure, such as RC active filters.
It should be noted that filtration module 4 or LC wave filters.
Embodiment two
Fig. 2 is the structural representation of embodiment two of isolated neutral capacitance current of distribution network measurement apparatus of the present utility model
Figure.
As shown in Fig. 2 the isolated neutral capacitance current of distribution network measurement apparatus of the present embodiment, including：
CPU module 1, it is used for the data signal for producing certain frequency, and is converted into simulation constant current through D/A modular converters 2
Signal is sent to signal transmitting and amplification module 3；The signal transmitting and amplification module 3 are used to believe the simulation constant current received
Transmitting injects power distribution network to voltage transformer 7 through voltage transformer 7 after number amplification；And
Current signal collection module 9, it is used for the current signal for gathering injection power distribution network；And
Second voltage transformer 8, it is connected with power distribution network, and the power distribution network return voltage for gathering Injection Current signal is believed
Number；And
The current signal collection module 9 and second voltage transformer 8 pass sequentially through filtration module 4 and A/D moduluss of conversion
Block 5 is connected with CPU module 1, and 1 isolated neutral capacitance current of distribution network measured value is exported by CPU module；
The output end of filtration module 4 is also connected with FPGA module 6, and the FPGA module 6 is connected with CPU module 1.
In the present embodiment, CPU module 1 is also connected with high in the clouds memory module 10.
Wherein, high in the clouds memory module 10 can use RAM or other extraneous storage devices, such as USB flash disk or SD card.
In the present embodiment, the CPU module 1 is also connected with communication module 11, the communication module 11 and remote monitoring
Server is connected.
Wherein, communication module 11 can be wireless communication module or wire cable.
Wireless communication module can be realized using Wifi modules or Zigbee module.
In the present embodiment, the CPU module 1 is also connected with human-computer interaction module 12.
Wherein, the human-computer interaction module 12 includes touch-screen and keyboard.
Touch-screen can use Eview-ET070 touch-screens.
In the present embodiment, the filtration module 4 is active power filtering module.
Wherein, the structure of active power filtering module can be realized using existing structure, such as RC active filters.
It should be noted that filtration module 4 or LC wave filters.
The principle of isolated neutral capacitance current of distribution network measurement apparatus of the present utility model is：
When constant current signal injects power distribution network through first voltage transformer open delta side, due to first voltage transformer
Excitation impedance is much larger than short-circuit impedance and power distribution network capacitance to earth, now injects power distribution network electric current and is believed by measurement apparatus output constant current
Number determine.When measuring return voltage signal through second voltage transformer open delta side, this second voltage transformer open delta
Side is unloaded, considers that now second voltage transformer star side signal code is almost nil, and excitation voltage is identical with star side voltage,
The now earth-free capacitance current of distribution network measurement of second voltage transformer internal impedance centering point does not influence, and can be achieved to join over the ground
Number accurately measures.
CPU module obtains according to the current signal of injection power distribution network and the power distribution network return voltage signal of Injection Current signal
To isolated neutral power distribution network capacitance, isolated neutral capacitance current of distribution network value is finally accurately tried to achieve.
Isolated neutral capacitance current of distribution network measured value and actual comparison are as shown in table 1：When Injection Current is fixed
Amplitude is 1A, and when phase is 0 °, measured capacitance values are bigger, and actual capacitance current value is higher, and measurement accuracy is lower.Work as measured capacitance
Value is bigger, is more difficult to by measuring return voltage signal of change isolated neutral capacitance current of distribution network.Experiment proof, this reality
It is less than 0.2% with new measurement error, meets isolated neutral power distribution network actual motion requirement.
Table 1
A kind of isolated neutral capacitance current of distribution network measurement apparatus provided by the utility model, can be accurately measured
Isolated neutral capacitance current of distribution network；
The device of the present utility model eliminates the influence of voltage transformer internal impedance, and parameter measurement precision is high；
Post-set arc suppression coils do not put into operation in power distribution network normal operation, equivalent to ungrounded electric net work, therefore, this reality
It is equally applicable to be grounded power distribution network through post-set arc suppression coils with the new device.
It is not new to this practicality although above-mentioned specific embodiment of the present utility model is described with reference to accompanying drawing
The limitation of type protection domain, one of ordinary skill in the art should be understood that on the basis of the technical solution of the utility model, ability
Field technique personnel need not pay the various modifications that creative work can make or deformation still in protection model of the present utility model
Within enclosing.
Claims (10)
- A kind of 1. isolated neutral capacitance current of distribution network measurement apparatus, it is characterised in that including：CPU module, it is used for the data signal for producing certain frequency, and is converted into simulation constant current signal through D/A modular converters and passes Deliver to signal transmitting and amplification module；After the simulation constant current signal that the signal transmitting and amplification module are used to receive amplifies Transmitting is to first voltage transformer, the open delta wiring injection power distribution network through first voltage transformer；AndCurrent signal collection module, it is used for the current signal for gathering injection power distribution network；AndSecond voltage transformer, it is connected with power distribution network, for gathering the power distribution network return voltage signal of Injection Current signal；AndThe current signal collection module and second voltage transformer pass sequentially through filtration module and A/D modular converters and CPU Module is connected, and isolated neutral capacitance current of distribution network measured value is exported by CPU module.
- 2. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 1, it is characterised in that filtration module Output end be also connected with FPGA module, the FPGA module is connected with CPU module.
- 3. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 1, it is characterised in that the CPU Module is also connected with high in the clouds memory module.
- 4. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 1, it is characterised in that the CPU Module is also connected with communication module, and the communication module is connected with remote monitoring server.
- 5. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 4, it is characterised in that the communication Module is wireless communication module or wire cable.
- 6. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 5, it is characterised in that described wireless Communication module is Wifi modules or Zigbee module.
- 7. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 1, it is characterised in that the CPU Module is also connected with human-computer interaction module.
- 8. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 7, it is characterised in that described man-machine Interactive module includes touch-screen and keyboard.
- 9. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 1, it is characterised in that the filtering Module is active power filtering module.
- 10. isolated neutral capacitance current of distribution network measurement apparatus as claimed in claim 9, it is characterised in that the filter Ripple module is RC active filters.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721308787.3U CN207198234U (en) | 2017-10-11 | 2017-10-11 | A kind of isolated neutral capacitance current of distribution network measurement apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721308787.3U CN207198234U (en) | 2017-10-11 | 2017-10-11 | A kind of isolated neutral capacitance current of distribution network measurement apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207198234U true CN207198234U (en) | 2018-04-06 |
Family
ID=61787881
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721308787.3U Active CN207198234U (en) | 2017-10-11 | 2017-10-11 | A kind of isolated neutral capacitance current of distribution network measurement apparatus |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207198234U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110927517A (en) * | 2019-11-14 | 2020-03-27 | 长沙理工大学 | Method and system for measuring ground insulation parameters of neutral point ungrounded distribution network by using star-shaped capacitor |
| CN111103501A (en) * | 2018-10-09 | 2020-05-05 | 长沙理工大学 | Method and system for measuring ground insulation parameters of ungrounded neutral point power distribution network |
| CN113125899A (en) * | 2021-03-05 | 2021-07-16 | 国网江苏省电力有限公司盐城供电分公司 | Single-phase earth fault tuning method based on secondary signal injection |
-
2017
- 2017-10-11 CN CN201721308787.3U patent/CN207198234U/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111103501A (en) * | 2018-10-09 | 2020-05-05 | 长沙理工大学 | Method and system for measuring ground insulation parameters of ungrounded neutral point power distribution network |
| CN111103501B (en) * | 2018-10-09 | 2022-05-20 | 长沙精科电力技术有限公司 | Method and system for measuring ground insulation parameters of ungrounded neutral point power distribution network |
| CN110927517A (en) * | 2019-11-14 | 2020-03-27 | 长沙理工大学 | Method and system for measuring ground insulation parameters of neutral point ungrounded distribution network by using star-shaped capacitor |
| CN110927517B (en) * | 2019-11-14 | 2022-01-25 | 长沙理工大学 | Method and system for measuring ground insulation parameters of neutral point ungrounded distribution network by using star-shaped capacitor |
| CN113125899A (en) * | 2021-03-05 | 2021-07-16 | 国网江苏省电力有限公司盐城供电分公司 | Single-phase earth fault tuning method based on secondary signal injection |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101458277B (en) | Three phase electric energy measurement apparatus | |
| CN101441231B (en) | Harmonic electric energy metering error analytical apparatus | |
| CN207198234U (en) | A kind of isolated neutral capacitance current of distribution network measurement apparatus | |
| CN107390081A (en) | It is a kind of to be used for the device and method being monitored powered to deformation of transformer winding | |
| CN103604991B (en) | The busbar voltage phase measurement device of capacitance type potential transformer and method | |
| CN101937024A (en) | Capacitance measurement method and measurement device for power distribution network with neutral point grounded through arc suppression coil | |
| CN102279311A (en) | Method for online detection and total loss determination of neutral current of distribution transformer | |
| CN205038273U (en) | Measurement device for earthing device power frequency and impact characteristic parameter | |
| CN104132610A (en) | Distribution network transformer low-voltage winding deformation belt electric detection device and method | |
| CN103712551A (en) | Power distribution network transformer low-voltage winding deformation on-line monitoring device and method | |
| CN106324353A (en) | Inductive filtering converter transformer harmonic wave impedance measurement method and device | |
| CN203722628U (en) | Power carrier channel communication tester | |
| CN207181589U (en) | It is a kind of to be used for the device being monitored powered to deformation of transformer winding | |
| CN101949979A (en) | Method for measuring resistance of ground wire of transformer | |
| CN102981061B (en) | Direct-to-ground capacitance measuring instrument in a kind of transformer station distribution system | |
| CN103715765A (en) | Substation fully-enclosed gas insulation combination electric appliance circulation inhibition device and method | |
| CN111103500A (en) | Resonance grounding power distribution network ground parameter measurement method considering damping resistance | |
| CN201859177U (en) | Measurement module for low-frequency alternating current signal in relay protection device | |
| CN104459370A (en) | Converter transformer broadband electromagnetic transient analysis model based on double transmission line structures | |
| CN204462246U (en) | A kind of HVDC (High Voltage Direct Current) transmission line corona loss measuring system | |
| CN106646136A (en) | Method and system for locating single-phase earth fault of parallel damping turn-adjustable type arc-extinction coil | |
| CN205176195U (en) | Insulating status monitoring device of cable jacket | |
| CN203275517U (en) | Multifunctional three-phase harmonic wave electric energy meter | |
| CN207281235U (en) | A kind of partial discharge intensity's detection circuit based on series process | |
| CN206074694U (en) | A kind of intelligent earth resistance tester |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |