CN203164267U - Large-scale grounding grid metal framework shunt vector measuring system based on wireless transmission - Google Patents
Large-scale grounding grid metal framework shunt vector measuring system based on wireless transmission Download PDFInfo
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- CN203164267U CN203164267U CN 201320143557 CN201320143557U CN203164267U CN 203164267 U CN203164267 U CN 203164267U CN 201320143557 CN201320143557 CN 201320143557 CN 201320143557 U CN201320143557 U CN 201320143557U CN 203164267 U CN203164267 U CN 203164267U
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Abstract
The utility model discloses a large-scale grounding grid metal framework shunt vector measuring system based on wireless transmission, which comprises a variable frequency signal source, a coupling transformer, a frequency-selecting ammeter, a frequency-selecting voltmeter, a current transformer, a wireless communication instrument, a wireless transmitting antenna, a Rogowski coil, a wireless receiving antenna and a frequency-selecting multimeter, wherein the variable frequency signal source is connected with an input end of the coupling transformer, one path of an output end of the coupling transformer is connected with a remote current electrode, another path of the output end is sequentially connected with the frequency-selecting ammeter and the current transformer in series and then connected with a grounding sown lead, an input end of the frequency-selecting voltmeter is connected with a grounding down lead of a tested large-scale grounding grid, and an output end is connected with a remote voltage electrode; output of the current transformer is connected with the wireless communication instrument, and the wireless communication instrument is externally connected with the wireless transmitting antenna; a port of the frequency-selecting multimeter is connected with the wireless receiving antenna, and another port is connected with the Rogowski coil so as to encircle a certain metal framework within a region of the large-scale grounding grid. The measuring system disclosed by the utility model can improve and realize accurate evaluation on the state of the grounding grid.
Description
Technical field
The utility model relates in the power industry measuring equipment that divides flow vector, the measuring system that the measuring method that specifically refers to the large-scale grounding network impedance ground is divided flow vector based on the large-scale earth mat metal frame of wireless transmission.
Background technology
Generating plant, grounding net of transformer substation are except providing common reference ground for various electrical equipments, more importantly, play the fault current of fast and effeciently releasing in system's generation earth fault or when being struck by lightning, improving grounded screen and the face of land, place earth potential distributes, ensureing the effect of first and second equipment and personal security, is the important measures of safeguarding power system security reliability service, support personnel and device security.
Impedance ground is the important parameter that characterizes the earth mat performance.Impedance ground is defined as, and earth mat is injected measuring current Im, records the corresponding current potential lifting of earth mat U, impedance ground Z=U/Im with voltage table then.As seen, all test results of grounded screen all are based upon on this basic data of measuring current Im of injecting earth mat.The real current value that accurately obtains injecting current earth mat is extremely important, directly influences test result.
After power plant and transformer station put into operation, the access of aerial earth wire and crosslinked cable screen layer had changed the topological structure of former grounded screen inevitably, and measuring current has been produced bigger shunting action.The measuring current that is instrument output is not all injected current earth mat, but has been diverted to a distant place by aerial earth wire.Shunt influence how accurately to get rid of transformer station's aerial earth wire and cable records the true impedance ground of substation ground network, becomes a difficult problem and the challenge of perplexing engineering technical personnel for a long time.
When the grounded screen impedance ground is measured, conductor in grounded screen injects a power current or non-power-frequency current, electric current will form the loop between grounded screen and the electric current utmost point, obtain a grounded screen Potential distribution of big ground surface on every side, if grounded screen is independently, be that grounded screen and other metallic earthing body do not have and be electrically connected, then measuring current is all loose by grounded screen to be measured and is flow in the earth, and this moment, measurement result reflected the true impedance ground of grounded screen.And if grounded screen and the existence of other metal grounding body are electrically connected, the partial test electric current will flow out by other metal grounding body, and namely other grounding body is shunted measuring current, and stream has been made contribution to loosing, the measuring current that flows through from grounded screen reduces, and causes the impedance ground measurement result less than normal.
The substation ground network area is bigger, underground grounding body becomes the latticed layout of burying underground, ground metal frame links to each other with extraneous aerial earth wire, numerous metal frames link to each other by framework each other simultaneously, earth mat, metal frame, aerial earth wire, cable jacket has constituted a resistance inductance network jointly, and the shunting of alternating-current measurement electric current on each Base Metal framework of injecting earth mat is not reverse completely, but has certain phase difference.For some large-scale transformer stations, also exist circulation between the metal frame framework.
Because what when test injected earth mat is an alternating current, its direction of current with the sine wave period of about 50 of per seconds in real-time change.Measure the vector of metal frame shunting, at first want to compare in real time the metal frame shunting with respect to the phase differential of measuring current.When substation ground network is measured in the past, because the restriction of technical merit and testing apparatus, under a lot of situations or not geodesic line shunting fully, or only survey the mould value size of metal frame shunting, and its phase place of accident.The influence that aerial earth wire looses and flows is not then considered in the accident shunting, and the calculated value of final test electric current is bigger than normal; Survey shunting size (mould value) and the accident phase differential, then all shuntings all can only regard the stream that looses beyond the earth mat, and its direction and complete anti-phase calculating of the measuring current of injecting earth mat, then the calculated value of final test electric current is less than normal; Sometimes the measured divergent die value addition of each metal frame even surpassed the measuring current of injecting can't obtain logical test result.Only accurately measure the vector of shunting everywhere, then measuring current and each shunting are asked vector sum, just can obtain injecting the accurate electric current of earth mat.
The utility model content
The purpose of this utility model provides a kind of measuring system of dividing flow vector based on the large-scale earth mat metal frame of wireless transmission, this measuring system can go out the branch flow vector that large-scale grounding network connects metal frame by in-site measurement, improved the accuracy of metal frame shunting vector measurement, avoided great Systematic Errors, the accurate evaluation of the ground net state that achieves a butt joint.
This purpose of the present utility model realizes by following technical solution: the measuring system of dividing flow vector based on the large-scale earth mat metal frame of wireless transmission, it is characterized in that: this measuring system comprises the frequency variation signal source, coupling transformer, the frequency-selecting reometer, frequency selective voltmeter, current transformer, the wireless telecommunications instrument, the wireless transmit antenna, Luo-coil, wireless receiving antenna and frequency-selecting multimeter, described frequency variation signal source links to each other with the input end of coupling transformer, the output terminal of coupling transformer divides two-way output, the lead of leading up to is connected to the distant place electric current utmost point, the lead of the leading up to described frequency-selecting reometer of connecting successively, be connected with the down conductor of tested large-scale earth mat behind the current transformer, inject measuring current to tested large-scale earth mat, the input end of described frequency selective voltmeter is connected with the down conductor of tested large-scale earth mat, and output terminal connects distant place voltage pole; Described current transformer can obtain the information of measuring current, and the output of described current transformer connects the wireless telecommunications instrument, the external wireless transmit antenna of wireless telecommunications instrument, and the information wireless of the measuring current that wireless transmit antenna current mutual inductor obtains is launched; A port on the described frequency-selecting multimeter connects the wireless receiving antenna, be used for to receive the phase information of the measuring current that the wireless transmit antenna sends, another port connects Luo-coil, described Luo-coil circle is lived a certain metal frame in this large-scale ground web area, obtain the partial current information of a certain metal frame, described frequency-selecting multimeter will compare from wireless receiving antenna the measuring current information that obtains and the partial current information that obtains from Luo-coil, obtain the branch flow vector of a certain metal frame in the large-scale earth mat, branch flow vector by all metal frames that will obtain carries out addition and asks vector sum, obtains the shunting vector value of this large-scale earth mat metal frame.
Measuring system of the present utility model can divide flow vector to measure to large-scale earth mat metal frames such as operation generating plant, transformer stations, adopt Radio Transmission Technology, wireless transmission phase information between the measuring shunt point of measuring current decanting point and each metal frame, obtain in real time each minute flow vector and the measuring current vector between phase differential, obtain the branch flow vector of metal frame in this large-scale ground web area by mathematics manipulation, comprise amplitude and phase differential.This method has solved the on-the-spot difficult problem that can't measure the branch flow vector in the past, and the diverting coefficient that moves large-scale earth mat for accurate Calculation provides technical guarantee
In the utility model, described large-scale earth mat refers to the large-scale grounding network of transformer station or power plant.
In the utility model, described frequency variation signal source refers to the non-power-frequency current of frequency range between 40～70Hz to the measuring current that tested large-scale earth mat injects.
In the utility model, the coverage of the wireless transmission between the decanting point of described measuring current and the metal frame partial current measurement point is greater than 50 meters.
In the utility model, described Luo-coil is that length is greater than the flexible opening Luo-coil of 300mm.
The utility model systemic-function implementation procedure is as follows:
(1) the frequency variation signal source is connected to coupling transformer, and coupling transformer output is injected the measuring current of an alien frequencies to tested grounded screen, and keeps constant in test process.
(2) utilize the current transformer sampling to obtain the waveform of measuring current, with its phase information, send by the wireless transmit antenna after handling.
(3) far-end frequency-selecting multimeter has wireless receiving antenna, but this phase data of wireless receiving, and will send into the CPU of frequency-selecting multimeter after this data processing.
(4) another interface of frequency-selecting multimeter connects flexible Luo-coil, circle is lived metal frame, obtain current signal, handle through frequency-selective filtering, get rid of wherein 50Hz and other undesired signal, obtain its mould value size, simultaneously with wireless receiving to the measuring current phase information carry out the phase bit comparison, draw phase differential.
(5) calculate each metal frame shunting vector sum, obtain total shunting size.
Compared with prior art, measuring system of the present utility model has following remarkable result:
(1) measuring system of the present utility model, system comes the current and phase difference of compare test electric current and two different locations of metal frame by Wireless transmission mode, thereby obtains the branch flow vector of large-scale earth mat metal frame.
(2) measuring system of the present utility model, wireless communication apparatus obtains test current signals by current transformer, after treatment this information is carried out wireless transmit.The frequency-selecting multimeter has internal or external receiving antenna and treatment circuit, has the wireless receiving function, but wireless receiving is to this phase information.The wireless transmission receiving range is greater than 50 meters.
(3) measuring system of the present utility model, the frequency-selecting multimeter has the port that connects flexible Luo-coil, can live metal frame by the Luo-coil circle and measure shunting size and waveform on the framework, and with wireless receiving to phase place compare, directly demonstrate size and the phase differential of shunting.
(4) measuring system of the present utility model, the frequency-selecting multimeter has the port that connects flexible Luo-coil, can live metal frame by the Luo-coil circle and measure shunting size and waveform on the framework, and with wireless receiving to phase place compare, directly demonstrate size and the phase differential of shunting.
(5) measuring system of the present utility model, flexible Luo-coil adopt and lengthen design, live the needs of very thick metal frame to satisfy on-the-spot circle, and Luo-coil length is greater than 300mm.
(6) measuring system of the present utility model, frequency variation signal source and coupling transformer are the non-power-frequency currents of a 40～70Hz to the earth mat injection, measure the frequency-selective filtering technology that then adopts, disturb to get rid of 50Hz power frequency very strong in the transformer station, obtain size and phase place accurately.
Description of drawings
Below in conjunction with the drawings and specific embodiments the utility model is described in further details.
Fig. 1 is the utility model divides the measuring system of flow vector based on the large-scale earth mat metal frame of wireless transmission one-piece construction synoptic diagram.
Description of reference numerals
1, frequency variation signal source; 2, coupling transformer; 3, frequency-selecting reometer; 4, current transformer;
5, wireless telecommunications instrument; 6, wireless transmit antenna; 7, frequency selective voltmeter; 8, distant place voltage pole;
9, the distant place electric current utmost point; 10, Luo-coil; 11, frequency-selecting multimeter; 12, wireless receiving antenna;
13, metal frame; 14, electric power pylon
Embodiment
The measuring system of dividing flow vector based on transformer station's metal frame of wireless transmission as shown in Figure 1, this measuring system comprises frequency variation signal source 1, coupling transformer 2, frequency-selecting reometer 3, frequency selective voltmeter 7, current transformer 4, wireless telecommunications instrument 5, wireless transmit antenna 6, Luo-coil 10, wireless receiving antenna 12 and frequency-selecting multimeter 11, frequency variation signal source 1 links to each other with the input end of coupling transformer 2, the output terminal of coupling transformer 2 divides two-way output, the lead of leading up to is connected to the distant place electric current utmost point 9, the lead of the leading up to frequency-selecting reometer 3 of connecting successively, current transformer 4 backs are connected with the down conductor of tested transformer station, inject measuring current to tested transformer station, the input end of frequency selective voltmeter 7 is connected with the down conductor of tested transformer station, and output terminal connects distant place voltage pole 8; Current transformer 4 can obtain the information of measuring current, and the output of current transformer 4 connects wireless telecommunications instrument 5, wireless telecommunications instrument 5 external wireless transmit antennas 6, and the information wireless of the measuring current that wireless transmit antenna 6 current transformers 4 obtain is launched; A port on the frequency-selecting multimeter 11 connects wireless receiving antenna 12, be used for to receive the phase information of the measuring current that wireless transmit antenna 6 sends, another port connects Luo-coil 10, Luo-coil 10 circles are lived a certain metal frame 13 in this transformer station zone, obtain the partial current information of a certain metal frame 13, frequency-selecting multimeter 11 will compare from wireless receiving antenna 12 the measuring current information that obtains and the partial current information that obtains from Luo-coil 10, obtain the branch flow vector of a certain metal frame 13 in the transformer station, branch flow vector by all metal frames 13 that will obtain carries out addition and asks vector sum, obtains the shunting vector value of this transformer station's metal frame 13.
In the present embodiment, described frequency variation signal source refers to the non-power-frequency current of frequency range between 40～70Hz to the measuring current that tested large-scale earth mat injects; The coverage of the wireless transmission between the decanting point of described measuring current and the metal frame partial current measurement point is greater than 50 meters; Described Luo-coil is that length is greater than the flexible opening Luo-coil of 300mm.
Measuring system of the present utility model is not only applicable on the metal frame shunting vector measurement of above-mentioned transformer station, also can be applied on the metal frame shunting vector measurement such as large-scale earth mats such as power plant, operate identical with the metal frame shunting vector measurement of above-mentioned transformer station.
The model that wireless telecommunications instrument in the present embodiment selects for use Shanghai big sail Electric Appliance Equipment Co., Ltd to produce is the wireless telecommunications instrument of DFWF; The model that frequency selective voltmeter, frequency-selecting reometer and frequency-selecting multimeter select for use Shanghai big sail Electric Appliance Equipment Co., Ltd to produce is the multi-functional frequency-selecting volometer of DF9006; The model that flexible opening Luo-coil selects for use Shanghai big sail Electric Appliance Equipment Co., Ltd to produce is the flexible opening Luo-coil of DFRC.
Measuring system of the present utility model, make when connecing metal frame shunting vector measurement, according to the method for regulation among the DL/T475-2006 " the earthing device characterisitic parameter is measured guide rule ", of a frequency variation signal source, earth mat is injected a non-power-frequency current Im, and in measuring whole process, keep this current stabilization.Utilize the measuring current sampling of current transformer to injecting, through AD conversion and frequency-selective filtering calculation process, obtain waveform and the phase information of measuring current, this phase place is defined as reference phase, i.e. zero phase.
This reference phase information wireless is launched, and far-end frequency-selecting multimeter is built-in with radio receiver, but wireless receiving and is sent into the CPU of frequency-selecting multimeter to this phase data after will these data handling.
Another port spreading degree of the multimeter of frequency-selecting simultaneously is the above Luo-coil (flexible current mutual inductor) of 300mm, the metal frame that circle firmly links to each other with aerial earth wire, and sampling obtains the partial current signal on the metal frame; Through AD conversion and frequency-selective filtering calculation process, get rid of 50Hz and other interference, extract the shape information of non-power-frequency current, also send into CPU.The CPU computing compare and partial current phase place and wireless receiving to the measuring current phase place compare, then can obtain size and the phase differential of this Base Metal framework shunting, can obtain the vector that this Base Metal framework is shunted.
According to said method, measure the shunting of all metal frames that link to each other with aerial earth wire in the transformer station, and the shunting on the crosslinked cable oversheath, obtain the vector that each is shunted.The vector of all shuntings is carried out plural addition ask vector sum, then can obtain whole ground wire branch flow valuve.
During said method is implemented, the technological difficulties of several keys are arranged: how (1) extracts faint shunting signal under strong jamming.Consider that framework footing, iron tower column foot and high-tension cable oversheath size are bigger, the applicant develops specially and had both satisfied dimensional requirement, guarantee the flexible Rogowski coil (abbreviation Luo-coil) of enough accuracy again, solved the measuring shunt problem in the actual measurement of earth mat impedance ground.(2) filtering and the frequency-selective filtering processing of the current signal of the surveying interference of on-the-spot institute.Developed corresponding anti-interference frequency-selective filtering disposal system at present, can handle the measured feeble signal in scene.(3) the communication transmission of phase information.Because transformer station's area is bigger, and need in the scope of place, hold the traverse measurement everywhere of frequency-selecting multimeter when dividing current test, need design a covering device phase information is passed to the frequency-selecting multimeter that far-end moves accurately and reliably.
Above-described embodiment of the present utility model is not the restriction to the utility model protection domain; embodiment of the present utility model is not limited thereto; according to foregoing of the present utility model; ordinary skill knowledge and customary means according to this area; do not breaking away under the above-mentioned basic fundamental thought of the utility model prerequisite; modification, replacement or the change of other various ways that said structure of the present utility model is made all drop within the protection domain of the present utility model.
Claims (5)
1. the measuring system of dividing flow vector based on the large-scale earth mat metal frame of wireless transmission, it is characterized in that: this measuring system comprises the frequency variation signal source, coupling transformer, the frequency-selecting reometer, frequency selective voltmeter, current transformer, the wireless telecommunications instrument, the wireless transmit antenna, Luo-coil, wireless receiving antenna and frequency-selecting multimeter, described frequency variation signal source links to each other with the input end of coupling transformer, the output terminal of coupling transformer divides two-way output, the lead of leading up to is connected to the distant place electric current utmost point, the lead of the leading up to described frequency-selecting reometer of connecting successively, be connected with the down conductor of tested large-scale earth mat behind the current transformer, inject measuring current to tested large-scale earth mat, the input end of described frequency selective voltmeter is connected with the down conductor of tested large-scale earth mat, and output terminal connects distant place voltage pole; Described current transformer can obtain the information of measuring current, and the output of described current transformer connects the wireless telecommunications instrument, the external wireless transmit antenna of wireless telecommunications instrument, and the information wireless of the measuring current that wireless transmit antenna current mutual inductor obtains is launched; A port on the described frequency-selecting multimeter connects the wireless receiving antenna, be used for to receive the phase information of the measuring current that the wireless transmit antenna sends, another port connects Luo-coil, described Luo-coil circle is lived a certain metal frame in this large-scale ground web area, obtain the partial current information of a certain metal frame, described frequency-selecting multimeter will compare from wireless receiving antenna the measuring current information that obtains and the partial current information that obtains from Luo-coil, obtain the branch flow vector of a certain metal frame in the large-scale earth mat, branch flow vector by all metal frames that will obtain carries out addition and asks vector sum, obtains the shunting vector value of this large-scale earth mat metal frame.
2. measuring system of dividing flow vector based on the large-scale earth mat metal frame of wireless transmission according to claim 1, it is characterized in that: described large-scale earth mat refers to the large-scale grounding network of transformer station or power plant.
3. measuring system of dividing flow vector based on the large-scale earth mat metal frame of wireless transmission according to claim 1 is characterized in that: described frequency variation signal source refers to the non-power-frequency current of frequency range between 40～70Hz to the measuring current that tested large-scale earth mat injects.
4. measuring system of dividing flow vector based on the large-scale earth mat metal frame of wireless transmission according to claim 1, it is characterized in that: the coverage of the wireless transmission between the decanting point of described measuring current and the metal frame partial current measurement point is greater than 50 meters.
5. measuring system of dividing flow vector based on the large-scale earth mat metal frame of wireless transmission according to claim 1, it is characterized in that: described Luo-coil is that length is greater than the flexible opening Luo-coil of 300mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320143557 CN203164267U (en) | 2013-03-26 | 2013-03-26 | Large-scale grounding grid metal framework shunt vector measuring system based on wireless transmission |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201320143557 CN203164267U (en) | 2013-03-26 | 2013-03-26 | Large-scale grounding grid metal framework shunt vector measuring system based on wireless transmission |
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| CN203164267U true CN203164267U (en) | 2013-08-28 |
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| CN 201320143557 Withdrawn - After Issue CN203164267U (en) | 2013-03-26 | 2013-03-26 | Large-scale grounding grid metal framework shunt vector measuring system based on wireless transmission |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103235168A (en) * | 2013-03-26 | 2013-08-07 | 上海大帆电气设备有限公司 | Measuring system for shunt vectors of metal frames of large ground grids on basis of wireless transmission |
| CN103823101A (en) * | 2014-03-14 | 2014-05-28 | 云南电力试验研究院（集团）有限公司电力研究院 | Method for measuring impact current division coefficient of power transmission line tower with lightning conductor |
| CN110082633A (en) * | 2019-04-23 | 2019-08-02 | 史磊 | A kind of grounding net of transformer substation on-line monitoring system and method |
-
2013
- 2013-03-26 CN CN 201320143557 patent/CN203164267U/en not_active Withdrawn - After Issue
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103235168A (en) * | 2013-03-26 | 2013-08-07 | 上海大帆电气设备有限公司 | Measuring system for shunt vectors of metal frames of large ground grids on basis of wireless transmission |
| CN103235168B (en) * | 2013-03-26 | 2015-03-25 | 上海大帆电气设备有限公司 | Measuring system for shunt vectors of metal frames of large ground grids on basis of wireless transmission |
| CN103823101A (en) * | 2014-03-14 | 2014-05-28 | 云南电力试验研究院（集团）有限公司电力研究院 | Method for measuring impact current division coefficient of power transmission line tower with lightning conductor |
| CN103823101B (en) * | 2014-03-14 | 2016-04-20 | 云南电力试验研究院（集团）有限公司电力研究院 | A kind of electric power line pole tower of measuring tape lightning conducter impacts the method for diverting coefficient |
| CN110082633A (en) * | 2019-04-23 | 2019-08-02 | 史磊 | A kind of grounding net of transformer substation on-line monitoring system and method |
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