CN206832876U - A kind of DC earthing system power monitoring device - Google Patents
A kind of DC earthing system power monitoring device Download PDFInfo
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- CN206832876U CN206832876U CN201720419696.0U CN201720419696U CN206832876U CN 206832876 U CN206832876 U CN 206832876U CN 201720419696 U CN201720419696 U CN 201720419696U CN 206832876 U CN206832876 U CN 206832876U
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- earthing system
- giant magnetoresistance
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- bridge
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- 238000012806 monitoring device Methods 0.000 title claims abstract description 20
- 238000004458 analytical method Methods 0.000 claims abstract description 15
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- 238000012545 processing Methods 0.000 claims abstract description 15
- QVFWZNCVPCJQOP-UHFFFAOYSA-N chloralodol Chemical compound CC(O)(C)CC(C)OC(O)C(Cl)(Cl)Cl QVFWZNCVPCJQOP-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000005259 measurement Methods 0.000 claims abstract description 12
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 claims description 28
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- 239000000463 material Substances 0.000 claims description 7
- 239000002184 metal Substances 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000000919 ceramic Substances 0.000 claims description 2
- 230000005611 electricity Effects 0.000 claims description 2
- 239000011810 insulating material Substances 0.000 claims description 2
- 230000035945 sensitivity Effects 0.000 claims description 2
- 238000012544 monitoring process Methods 0.000 abstract description 9
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- 230000005856 abnormality Effects 0.000 abstract description 3
- 230000005404 monopole Effects 0.000 description 8
- 238000013461 design Methods 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
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- 238000004210 cathodic protection Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
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- 238000002360 preparation method Methods 0.000 description 1
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Abstract
The utility model discloses a kind of DC earthing system power monitoring device, it is related to power system measurement and on-line monitoring technique field.The DC earthing system power monitoring device, electric current in DC earthing system connectors is gathered by giant magnetoresistance sensor, and output difference signal is analyzed and processed for signal processing circuit, analysis result periodically or under abnormality is waken up into LoRa wireless communication modules and carries out remote data transmission, current information in DC earthing system connectors is sent to long-range transformer station, so that long-range transformer station monitors DC earthing system mode in real time；The DC earthing system power monitoring device internal structure is simple, and reliability is high, and measurement frequency, amplitude range are wide, batch making cost is cheap, long lifespan, and be hardly damaged under strong-electromagnetic field impact caused by high current effect, there is huge advantage in long-time monitors application scenario on-line.
Description
Technical field
The utility model belongs to power system measurement and on-line monitoring technique field, more particularly to a kind of DC earthing system
Current monitoring device.
Background technology
The change of current and ground connection are two the most key links of DC transmission system, and fault rate highest link.Ground connection
Safe operation of the system to DC transmission system has vital effect.The DC transmission system method of operation generally has two
Kind, one kind is bipolar operation, under such a method of operation, positive and negative polarities railway superstructures complete loops, and the electric current in two-wire line
Difference is out-of-balance current, is flowed into earthed system；Another kind is monopolar operation, including monopole ground return circuit is run and monopole metal
Loop is run, and when monopole metallic loop is run, a DC line forms direct current with another DC line as polar curve road and returned
Road, now the electric current of inflow earthed system is smaller, and in the operation of monopole ground return circuit, polar curve road and the earth form loop, now
There is upper kA huge current flow injection the earth.According to the above-mentioned method of operation, earthed system mainly has two kinds of effects：1）Bipolar operation
When, current conversion station neutral point potential is clamped down on, prevents the two poles of the earth voltage-to-ground imbalance from being caused damage to change of current station equipment；2）Monopole the earth
When loop is run, there is provided DC loop.No matter which kind of is acted on, and ground electrode system all has most important in DC transmission system
Effect.
Real time on-line monitoring is carried out to DC earthing system can effectively obtain the key message of DC earthing system, and increase is straight
Operating experience is flowed, prevents grounding system fault.The necessity that real time on-line monitoring is carried out to DC system grounding pole embodies
At following three aspects：1）Current straight-flow system time of putting into operation is short, lacks operation maintenance experience, and design without earthing pole
And the relevant criterion and specification of operation, DC earthing system power, which is monitored, can effectively accumulate related data and experience；
2）When monopole ground return circuit is run, there is huge current flow to flow into the earth, serious step voltage problem and D.C. magnetic biasing can be brought to ask
Topic, the former can bring potential danger to people, and the latter can cause the power equipment near earthing pole（Transformer, generator, relay are protected
Protection unit and reactive power compensator）Influenced by DC magnetic biasing and vibrate heating, efficiency reduce, mains by harmonics increase, now to entering
Earth-current, which is monitored, can quick and precisely position failure cause, avoid potential risk；3）Due to the effect of electrochemical corrosion, for a long time
Electric current, which flows into the earth, can cause earthing pole and neighbouring pipeline heavy corrosion, and earth current progress long term monitoring can effectively be assessed and connect
Earth polar and neighbouring corrosive pipeline degree, carry out taking safeguard measure in time（The measures such as cathodic protection）.
Although the monitoring to DC earthing system is highly desirable, current monitoring system still has problems, concentrates
In terms of being embodied in following four：1）The ripe and cheap current sensor of in the market, such as CT coils, Rogowski coil, measurement frequency
Scope does not include direct current, and measurement range includes the high precision electric current transducer of direct current（Such as optic current transformer）It is again more high
It is expensive；2）Current amplitude span to be measured is big, and required current sensor need to accurately measure as low as 1A out-of-balance current, big to several kA
Monopole ground return circuit operation earth current, it is necessary to current sensor range ability at least across 4 orders of magnitude；3）Electric current passes
Sensor short life, the design service life of direct current grounding pole is typically 30 years, existing sensor service life more than rare ten years
, a large amount of additional operational costs can be brought to the frequent maintenance of earthing pole current monitoring system；4）In view of straight-flow system monopole
Huge earth current when ground return circuit is run, ground electrode system are typically remote from the control centres such as transformer station（More than 10km）, when
The preceding CAN monitoring system wiring complexity to have come into operation, and wiring somewhat expensive over long distances, fault rate is high, using wireless
Communication, and overlength distance wireless telecommunications are a great problems.
Utility model content
In view of the shortcomings of the prior art, the utility model provides a kind of DC earthing system power monitoring device.
The utility model is that solve above-mentioned technical problem by the following technical solutions：A kind of DC earthing system electricity
Flow monitoring device, including giant magnetoresistance sensor, signal processing circuit and shielding insulation protecting box；Protected in the shielding insulation
The through hole passed through for DC earthing system connectors is offered on shield box, the giant magnetoresistance sensor is connected with signal processing circuit
Connect, and be fixed in shielding insulation protecting box；The sensitive direction of principal axis of the giant magnetoresistance sensor is along DC earthing system connectors
Tangential direction, the magnetic field of sensitive direction of principal axis is proportional to current amplitude in DC earthing system connectors；
The giant magnetoresistance sensor includes minute-pressure electric bridge, huge magnet-sensitive element, dielectric base and positioned at dielectric base
On pad, the minute-pressure electric bridge includes pedestal, the body of a bridge and piezoelectric patches, and the pedestal includes the first pedestal and the second pedestal, and
The both ends of dielectric base are fixed on by pad, the body of a bridge is connected between the first pedestal and the second pedestal, the piezoelectric patches
It is arranged on the body of a bridge and between the first pedestal and the second pedestal；The huge magnet-sensitive element is arranged on the lower section of the body of a bridge and edge
The center line of the body of a bridge arranges that the giant magnetic impedance that the huge magnet-sensitive element includes being connected in series by metal electrode senses in symmetry shape
Unit and giant magnetoresistance sensing unit, the other end of the giant magnetic impedance sensing unit have first electrode as whole huge magnetoelectricity
Input or the output electrode of sensor are hindered, the other end of the giant magnetoresistance sensing unit has second electrode as whole huge magnetic
The output of electric resistance sensor or input electrode.
Further, the piezoelectric patches uses piezoelectric ceramic thin sheet, is shaped as rectangle, the width of the piezoelectric patches and institute
It is consistent to state the width of the body of a bridge, the piezoelectric patches both ends are spaced away from pedestal, and the distance away from pedestal is equal.
Further, the thickness of the body of a bridge is the half of the base thickness.
Further, amplification module, logic analysis module, the LoRa that the signal processing circuit includes being sequentially connected are wireless
Communication module, the signal processing circuit also include power module and clock module, the power module respectively with the huge magnetic
Electric resistance sensor, amplification module, logic analysis module, LoRa wireless communication modules and clock module connection, the clock mould
Block is connected with logic analysis module and LoRa wireless communication modules respectively；The amplification module, for amplifying giant magnetoresistance sensing
The differential signal of device output, and suppression common mode is disturbed；The logic analysis module, amplification module is flowed through for analyzing and processing in real time
Signal, reduce in direct current grounding pole and flow through current amplitude, and analysis result is packed according to LoRa home control network communication protocols
And periodically or under abnormality wake up LoRa wireless communication modules and carry out remote data transmission, by DC earthing system connectors
Middle current information is sent to long-range transformer station；The power module, for providing power supply voltage signal for all modules；When described
Clock module, for providing clock signal for logic analysis module and LoRa wireless communication modules.
Further, the shell of the shielding insulation protecting box is three-decker, and outermost layer is using the high material of electrical conductivity
The interference of frequency electromagnetic waves is shielded, innermost layer is using magnetic field caused by the DC wire near high-permeability material shielding；It is middle
Layer is isolated using insulating materials；The shielding insulation protecting box, for providing mechanical protection, insulation protection for internal structure
And electromagnetic shielding, DC earthing system power monitoring device long-time normal work out of doors is effectively ensured.
Compared with prior art, DC earthing system power monitoring device provided by the utility model, passes through huge magnetoelectricity
The electric current in sensor collection DC earthing system connectors is hindered, and output difference signal is analyzed for signal processing circuit
Processing, analysis result periodically or under abnormality is waken up into LoRa wireless communication modules and carries out remote data transmission, will be straight
Current information in stream earthed system wire is sent to long-range transformer station, so that long-range transformer station monitors DC earthing system in real time
State；The DC earthing system power monitoring device internal structure is simple, and reliability is high, and measurement frequency, amplitude range are wide, batch
Cost of manufacture is cheap, long lifespan, and is hardly damaged under strong-electromagnetic field impact caused by high current effect, in online prison for a long time
Surveying in application scenario has huge advantage.
Brief description of the drawings
It is required in being described below to embodiment to use in order to illustrate more clearly of the technical solution of the utility model
Accompanying drawing is briefly described, it should be apparent that, drawings in the following description are only one embodiment of the present utility model, for
For those of ordinary skill in the art, on the premise of not paying creative work, other can also be obtained according to these accompanying drawings
Accompanying drawing.
Fig. 1 is a kind of structural representation of DC earthing system power monitoring device of the utility model；
Fig. 2 is the structural representation of the utility model giant magnetoresistance sensor；
Wherein：1- DC earthing system connectors, 2- giant magnetoresistance sensors, 3- amplification modules, 4- logic analysis modules, 5-
LoRa wireless communication modules, 6- clock modules, 7- power modules, 8- signal processing circuits, 9- shielding insulation protecting box, 10-
One pedestal, the pedestals of 11- second, 12- piezoelectric patches, 13- giant magnetic impedance sensing units, 14- giant magnetoresistance sensing units, 15- metals
Electrode, 16- first electrodes, 17- second electrodes.
Embodiment
With reference to the accompanying drawing in the utility model embodiment, technical scheme of this implementation in new is carried out clear, complete
Site preparation describes, it is clear that described embodiment is only the utility model part of the embodiment, rather than whole embodiments.
Based on the embodiment in the utility model, those of ordinary skill in the art are obtained on the premise of creative work is not made
Every other embodiment, belong to the utility model protection scope.
As depicted in figs. 1 and 2, DC earthing system power monitoring device provided by the utility model, including huge magnetoelectricity
Hinder sensor 2, signal processing circuit 8 and shielding insulation protecting box 9；Offered in the shielding insulation protecting box 9 for straight
The through hole that stream earthed system wire 1 passes through, the giant magnetoresistance sensor 2 is connected with signal processing circuit 8, and is fixed on screen
Cover in insulation protecting box 9；Tangential direction of the sensitive direction of principal axis of the giant magnetoresistance sensor 2 along DC earthing system connectors 1,
The magnetic field of sensitive direction of principal axis is set to be proportional to current amplitude in DC earthing system connectors 1；
The giant magnetoresistance sensor 2 includes minute-pressure electric bridge, huge magnet-sensitive element, dielectric base and positioned at dielectric base
On pad, the minute-pressure electric bridge includes pedestal, the body of a bridge and piezoelectric patches 12, and the pedestal includes the first pedestal 10 and the second pedestal
11, and the both ends of dielectric base are fixed on by pad, the body of a bridge is connected between the first pedestal 10 and the second pedestal 11, institute
Piezoelectric patches 12 is stated to be arranged on the body of a bridge and between the first pedestal 10 and the second pedestal 11；The huge magnet-sensitive element is arranged on
The lower section of the body of a bridge simultaneously arranges that the huge magnet-sensitive element includes connecting by the series connection of metal electrode 15 along the center line of the body of a bridge in symmetry shape
The giant magnetic impedance sensing unit 13 and giant magnetoresistance sensing unit 14 connect, the other end of the giant magnetic impedance sensing unit 13 have
Input or output electrode of the first electrode 16 as whole giant magnetoresistance sensor 2, the giant magnetoresistance sensing unit 14 it is another
One end has output or input electrode of the second electrode 17 as whole giant magnetoresistance sensor 2.
The signal processing circuit 8 includes amplification module 3, logic analysis module 4, the LoRa wireless telecommunications moulds being sequentially connected
Block 5, the signal processing circuit 8 also include power module 7 and clock module 6, the power module 7 respectively with the huge magnetoelectricity
Resistance sensor 2, amplification module 3, logic analysis module 4, LoRa wireless communication modules 5 and clock module 6 connect, the clock
Module 6 is connected with logic analysis module 4 and LoRa wireless communication modules 5 respectively.
The shell of the shielding insulation protecting box 9 is three-decker, and outermost layer is using the high material shields high frequency of electrical conductivity
The interference of electromagnetic wave, innermost layer is using magnetic field caused by the DC wire near high-permeability material shielding；Intermediate layer is using exhausted
Edge material is isolated；The shielding insulation protecting box 9, for providing mechanical protection, insulation protection and electromagnetism for internal structure
Shielding, is effectively ensured DC earthing system power monitoring device long-time normal work out of doors；Shielding with through hole
Insulation protecting box 9 is flexibly fixed on DC earthing system connectors 1, and keeps the two relative position constant, effectively ensure that
The stability of measurement result.
The giant magnetoresistance sensor 2 of selection measures magnetic field range in ± 1000 Oe, and sensitivity is 0.3 mV/V/Oe.Only will
Giant magnetoresistance sensor 2 is fixed on away from DC earthing system connectors 2cm opening positions, you can measurement is up to 10kA, as little as 1.5A's
Electric current, if desired further range extension, it is only necessary to by giant magnetoresistance sensor 2 further away from DC earthing system connectors 1
.The frequency measurement scope of selected giant magnetoresistance sensor 2 is direct current to 20MHz, either amplitude range or frequency
Giant magnetoresistance sensing 2 can cover measurement demand selected by scope.
Above disclosed is only specific embodiment of the present utility model, but the scope of protection of the utility model not office
It is limited to this, any one skilled in the art can readily occur in change in the technical scope that the utility model discloses
Change or modification, should all cover within the scope of protection of the utility model.
Claims (6)
- A kind of 1. DC earthing system power monitoring device, it is characterised in that：Including giant magnetoresistance sensor（2）, signal transacting Circuit（8）And shielding insulation protecting box（9）；In the shielding insulation protecting box（9）On offer and led for DC earthing system Line（1）The through hole passed through, the giant magnetoresistance sensor（2）And signal processing circuit（8）It is connected, and is fixed on shielding insulation Protecting box（9）It is interior；The giant magnetoresistance sensor（2）Tangential direction of the sensitive direction of principal axis along DC earthing system connectors, make The magnetic field of sensitive direction of principal axis is proportional to DC earthing system connectors（1）In current amplitude；The giant magnetoresistance sensor（2）Including minute-pressure electric bridge, huge magnet-sensitive element, dielectric base and in dielectric base Pad, the minute-pressure electric bridge includes pedestal, the body of a bridge and piezoelectric patches（12）, the pedestal includes the first pedestal（10）With the second base Seat（11）, and the both ends of dielectric base are fixed on by pad, the body of a bridge is connected to the first pedestal（10）With the second pedestal （11）Between, the piezoelectric patches（12）It is arranged on the body of a bridge and is located at the first pedestal（10）With the second pedestal（11）Between；It is described Huge magnet-sensitive element is arranged on the lower section of the body of a bridge and arranged along the center line of the body of a bridge in symmetry shape, and the huge magnet-sensitive element includes logical Cross metal electrode（15）The giant magnetic impedance sensing unit being connected in series（13）With giant magnetoresistance sensing unit（14）, the giant magnetoresistance Anti- sensing unit（13）The other end there is first electrode（16）As whole giant magnetoresistance sensor（2）Input or output electricity Pole, the giant magnetoresistance sensing unit（14）The other end there is second electrode（17）As whole giant magnetoresistance sensor（2） Output or input electrode.
- 2. DC earthing system power monitoring device as claimed in claim 1, it is characterised in that：The piezoelectric patches（12）Using Piezoelectric ceramic thin sheet, it is shaped as rectangle, the piezoelectric patches（12）Width it is consistent with the width of the body of a bridge, the piezoelectric patches （12）Both ends are spaced away from pedestal, and the distance away from pedestal is equal.
- 3. DC earthing system power monitoring device as claimed in claim 1, it is characterised in that：The thickness of the body of a bridge is institute State the half of base thickness.
- 4. DC earthing system power monitoring device as claimed in claim 1, it is characterised in that：The signal processing circuit （8）Including the amplification module being sequentially connected（3）, logic analysis module（4）, LoRa wireless communication modules（5）, the signal transacting Circuit（8）Also include power module（7）And clock module（6）, the power module（7）Respectively with the giant magnetoresistance sensor （2）, amplification module（3）, logic analysis module（4）, LoRa wireless communication modules（5）And clock module（6）Connection, when described Clock module（6）Respectively with logic analysis module（4）With LoRa wireless communication modules（5）Connection.
- 5. DC earthing system power monitoring device as claimed in claim 1, it is characterised in that：The shielding insulation protecting box （9）Shell be three-decker, outermost layer is using the interference of the high material shields frequency electromagnetic waves of electrical conductivity, and innermost layer is using high Magnetic field caused by DC wire near magnetoconductivity material shielding；Intermediate layer is isolated using insulating materials.
- 6. DC earthing system power monitoring device as claimed in claim 1, it is characterised in that：The giant magnetoresistance sensor （2）For magnetic-field measurement scope in ± 1000 Oe, sensitivity is 0.3 mV/V/Oe；Frequency measurement scope is direct current to 20MHz.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201720419696.0U CN206832876U (en) | 2017-04-20 | 2017-04-20 | A kind of DC earthing system power monitoring device |
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| CN201720419696.0U CN206832876U (en) | 2017-04-20 | 2017-04-20 | A kind of DC earthing system power monitoring device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110702965A (en) * | 2019-10-15 | 2020-01-17 | 清华大学 | Cable state monitoring sensor device |
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- 2017-04-20 CN CN201720419696.0U patent/CN206832876U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110702965A (en) * | 2019-10-15 | 2020-01-17 | 清华大学 | Cable state monitoring sensor device |
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