CN101452034B - Portable intelligent DC earthing searching instrument - Google Patents

Portable intelligent DC earthing searching instrument Download PDF

Info

Publication number
CN101452034B
CN101452034B CN200710094341XA CN200710094341A CN101452034B CN 101452034 B CN101452034 B CN 101452034B CN 200710094341X A CN200710094341X A CN 200710094341XA CN 200710094341 A CN200710094341 A CN 200710094341A CN 101452034 B CN101452034 B CN 101452034B
Authority
CN
China
Prior art keywords
resistance
amplifier
straight
flow system
ground connection
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
Application number
CN200710094341XA
Other languages
Chinese (zh)
Other versions
CN101452034A (en
Inventor
戴春怡
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
State Grid Corp of China SGCC
Shanghai Municipal Electric Power Co
Original Assignee
Shanghai Municipal Electric Power Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shanghai Municipal Electric Power Co filed Critical Shanghai Municipal Electric Power Co
Priority to CN200710094341XA priority Critical patent/CN101452034B/en
Publication of CN101452034A publication Critical patent/CN101452034A/en
Application granted granted Critical
Publication of CN101452034B publication Critical patent/CN101452034B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Abstract

A portable intelligent DC grounding finder, relating to the field of testing short circuit, broken circuit, leakage or incorrect connection on electric instrument, lines or elements, and detecting the failure in cables, transmission lines or networks. The invention is composed of a hand-held set with a converted DC clip style meter and a DC insulation monitor base. The invention uses the clip style meter to correctly find the grounded DC lines and furthermore looks up the specific grounding points of instrument, and correctly finds out the grounding point without DC, even if eliminates the grounding failure under the condition wherein field conditions are allowable, thereby avoiding inconvenience of changing operation modes, revising fixed values and long working time for looking when applying power failure in the work program for finding the grounding, fast and correctly finding the grounding point, which is suitable for testing the short circuit, the broken circuit, leakage or incorrect connection on the electric instrument, the lines and the elements, and detecting the failure in the cables, the transmission lines or the networks.

Description

A kind of portable intelligent DC earthing searching instrument
Technical field
A kind of portable intelligent DC earthing searching instrument, the sniffer field that relates to the proving installation and the electric fault of electrical property, be specifically related to a kind of to electric equipment, circuit or element carry out short circuit, open circuit, the test of leakage or incorrect connection, the field of the fault in exploration cable, transmission line or the network.
Background technology
The substation relay protection DC power system adopts suspended state at present; both positive-negative power was all earth-free; when if generation Insulation Problems in service causes direct-flow positive pole or minus earth; generally can not produce consequence immediately; if but that the consequence that another dc system grounding produces has taken place in untimely processing is very serious; so when direct current takes place by ground connection, should get rid of earth fault immediately; but because straight-flow system wiring complexity; will find out the DC earthing point past in thousands of power leads is to draw power supply to go for by one the tunnel one the tunnel; waste time and energy, and hide certain risk.In dc bus, inject AC signal and detect, but because the capacitance current that line-to-ground has electric capacity to cause disturbs normal the detection, this kind detection method is also unsatisfactory by exchanging split-core type meter.
Publication number is CN1070486, open day is that on 03 31st, 1993 Chinese patent discloses a kind of DC grounding monitor alarm device, it is characterized in that, insulation monitoring and warning device and working power with substitute power supply and be connected with transfer switch Q K, substitute to be equipped with between power supply and each zone and every loop and substitute switch 1K '-nK ', 1DK-nDK, insulation monitoring and warning device by two balance resistances, grounding relay and positive and negative mutually and two light emitting diodes, microswitch multimeter form.
Publication number is CN1580796, and open day is that 2005 02 month No. 16 Chinese patent discloses a kind of DC earthing current detection circuit.This circuit has: electric wire is used in ZCT energize line and skew, and is connected in series with divider resistance; The comparing voltage value generative circuit is according to the impedance variation of ZCT, based on the magnitude of voltage generation comparing voltage value of dividing potential drop between ZCT and divider resistance; And control circuit, detect whether produce the DC earthing electric current according to comparing voltage value; Wherein, for being become, small scope can detect range of current, have in skew and produce circuit with the drift current that produces drift current in the electric wire, if control circuit is judged comparing voltage value and is judged with more than the upper limit threshold ground connection, perhaps judge with below the lower threshold, then judge to produce the DC earthing electric current ground connection.
Publication number is CN2722265, open day is that on 08 31st, 2005 Chinese patent discloses a kind of DC earthing on-line testing instrument, comprise switch, transformer, resistance etc., concrete structure is that switch series is linked on the primary circuit of transformer, pressure regulator is connected in series on the secondary circuit of transformer, and resistance, adjustable resistance are connected in series on the secondary circuit of pressure regulator.Connect with pincers type alternating current ammeter then.
Publication number CN2859554, open day is that on 01 17th, 2007 Chinese patent discloses a kind of a kind of DC ground fault indicator that the invention discloses, it is characterized in that: sensor one end is connected with testing circuit one end, the testing circuit other end is connected with amplifying circuit one end, the amplifying circuit other end is connected with output circuit one end, and the power input of testing circuit, amplifying circuit, output circuit all is connected with working power.
Though more than search earth fault during 4 patent energy measurement substation relay protection direct supply generation DC ground fault, in actual field earth fault processing procedure, also can produce following problem:
The one, a lot of branch roads of traction often below the direct current branch finally must lean on stretching stream switch to distinguish a wherein branch road of ground connection; { scene often takes place } is difficult to find earth point by trying stretching stream as parasitic loop, 2 ground connection, cable louding or nameplates be unclear etc.;
The 2nd, after some old transforming plant DC ground connection; because the epoch are remote, go through and improve the back DC line intricate concrete trend that is hard to know DC load character and circuit that distributes; when judging ground connection, the stretching stream power supply of examination causes protective relaying maloperation; historical lesson makes scheduling, on duty, relay protection staff all be quite careful attitude to drawing protection equipment direct supply; especially under the situation of current power shortage, more need a kind of safety and DC earthing detection method easily.
The 3rd, when judging a certain equipment ground, this device of finally still will stopping using checks equipment, finally the positioning DC earth point;
The 4th, branch road detects not work at ordinary times or to insulate and well makes the branch road detection failure be in operation can not to be found, and branch road takes place during branch road ground connection detect and problem is arranged and need other DC earthing detector remove to search the ground connection branch road.
The 5th, anti-capacitive interference performance of present portable earthing searching instrument and less stable can not reliably be judged earth fault, and the user of service greatly influences the success ratio of searching earth point to the grasp of straight-flow system and instrument function and the experience of searching ground connection.
Therefore the field personnel presses for and a kind ofly can simple and reliablely search the earth point instrument under the situation that does not disconnect DC load, this appliance requires satisfies and to be subjected to individual and Effect of Environmental very little, and inner integrated intelligent handling procedure can be judged all kinds of dc system grounding, and guides the condition of a staff's search direction and a clear and definite detection conclusion.
Summary of the invention
In order to address the above problem; the invention provides a kind of use and when substation relay protection direct supply generation DC ground fault, search the novel detector of earth fault; use this novel monitor can change running status; finally find earth fault according to power supply architecture step by step by the direct current split-core type meter; direct current split-core type meter principle of work mode all can not influence the accuracy that it searches DC earthing for the complex situations of two tunnel ground connection and the interference of direct current branch capacitive etc., and antijamming capability is very strong.Utilize this to search instrument and can greatly make things convenient for searching of DC earthing, guarantee whenever safety problem can not take place owing to adopt microcomputer technology to carry out intelligent decision simultaneously, do not exchange pincerlike meter and search that ground capacitance discharges and recharges the hidden danger of bringing in the ground connection process, improve the security of searching DC earthing greatly.
A kind of portable intelligent DC earthing searching instrument of the present invention specifically is made up of hand-held set and two parts of base, and it is characterized in that: hand-held set connects a direct current reometer by a direct current pincerlike meter and forms, and base is made up of the single chip microcomputer assembly.
As shown in Figure 2, the improved DC ammeter of described hand-held set part is provided with ground connection alarm I pilot lamp, ground connection alarm II pilot lamp, the not closed pilot lamp of jaw, exchanges pilot lamp, direct current pilot lamp, electric current transfinite pilot lamp and warning horn on panel.
As shown in Figure 4, described base is one the D.C. isolation monitor of single chip microcomputer to be installed, and its concrete metering circuit hardware principle structure is as follows:
Resistance R+the upper end be connected with straight-flow system positive bus-bar+KM, lower end ground connection and with resistance R-the upper end be connected; Resistance R-lower end is connected with straight-flow system negative busbar-KM; These two resistance to earth that resistance is straight-flow system positive bus-bar and negative busbar;
The upper end of resistance R a is connected with straight-flow system positive bus-bar+KM, lower end ground connection and with the lower end of the upper end of resistance R b, contact J1, resistance R 2, amplifier U1+extreme, amplifier U2-upper end extreme, resistance R 3 interconnects; The lower end of resistance R b is connected and all is connected with straight-flow system negative busbar-KM with the lower end of resistance R c; The upper end of resistance R c is connected with contact J1; These 3 resistance of resistance R a, Rb and Rc are connected in order successively, form the resistance bridge that straight-flow system is measured insulation against ground resistance with the periodic closed and disconnected of contact J1 again;
The upper end of resistance R 1 is connected with straight-flow system positive bus-bar+KM, the upper end of lower end and resistance R 2 and amplifier U1-extremely be connected amplifier U1 output+signal; Resistance R 1, R2 and amplifier U1 form measurement over against the ground voltage sampling circuit;
The lower end of resistance R 3 is connected with the upper end of resistance R 4, amplifier U2+extreme the connection, amplifier U2 output-signal, the lower end of resistance R 4 is connected with straight-flow system negative busbar-KM; Resistance R 3, resistance R 4 and amplifier U2 form the negative voltage-to-ground sampling circuit of measurement;
The upper end of resistance R 5 is connected with the output positive signal end of amplifier U1, the upper end of lower end and resistance R 6, amplifier U3-extremely be connected; The output negative signal end of the lower end of resistance R 6 and amplifier U2, U3 amplifier+extremely be connected; Resistance R 5, R6 and amplifier U3 form measurement busbar voltage sampling circuit;
The left end ground connection of resistance R 7 and with amplifier U5+extremely be connected, right-hand member and amplifier U5-extremely be connected; Resistance R 7 and amplifier U5 form ground current and measure the loop;
The lower end of capacitor C is connected with straight-flow system negative busbar-KM, upper end and amplifier U4+extremely be connected; Amplifier U4-extreme ground connection; Capacitor C and amplifier U4 form dc bus alternating voltage sampling circuit;
Contact J2, the J4, the J6 that are provided with interconnect, and all with extreme being connected of right-hand member, amplifier U5-of resistance R 7, contact J2, J4, J6 also are connected with 10K, 15K, 5K resistance respectively; 10K, 15K, these 3 resistance of 5K are connected with straight-flow system positive bus-bar+KM again; These parts have been formed the incremental system that under the negative ground connection situation of straight-flow system ground connection branch road has ground current;
Contact J3, the J5, the J7 that are provided with interconnect, and are connected with straight-flow system negative busbar-KM, and contact J3, J5, J7 are connected with 10K ', 15K ', 5K ' resistance respectively again; 10K ', 15K ', 5K ' resistance also all with extreme being connected of right-hand member, amplifier U5-of resistance R 7; These parts have been formed the incremental system that under straight-flow system positive ground connection situation ground connection branch road has ground current;
Seal in constant current source 5mA respectively at 5k and this resistance place of 5K '.
Described base directly uses contact J6 and J7 ground connection to draw partially.
As shown in Figure 3, described base is provided with: the dc system grounding emergency warning lamp, withdraw from old detector emergency warning lamp, exchange and to scurry into direct current emergency warning lamp, the excessive warning emergency warning lamp of ground capacitance, the unstable emergency warning lamp of DC voltage, branch road and detect beginning emergency warning lamp, power switch, straight-flow system positive bus-bar+KM interface, earth terminal, straight-flow system negative busbar-KM interface and RS232 interface.
Compared with prior art, portable intelligent DC earthing searching instrument advantage of the present invention is:
1. utilize the little direct current pincerlike meter of high sensitivity to search the successful experience of ground connection at the scene, conclude to sum up and be compiled into expert diagnostic system, any babe in the wood is as long as just can use this device just can accurately find the DC line of ground connection and can further search the concrete earth point of equipment with pincerlike meter by reading in two minutes;
2. need not stretching stream at all and just can find earth fault exactly, even charged eliminating earth fault under the situation of conditions permit at the scene;
3 have avoided searching a series of inconvenience such as method of operation change, definite value correction and searching work time length that have a power failure and bring to the scheduling application in the ground connection working routine, find earth point rapidly and accurately.
Description of drawings
One-piece construction synoptic diagram when Fig. 1 is a duty of the present invention;
Fig. 2 is a hand-held set contour structures synoptic diagram one-piece construction synoptic diagram;
Fig. 3 is base contour structures and wiring schematic diagram;
Fig. 4 is the metering circuit hardware principle structural drawing of base;
Fig. 5 is the process flow diagram of the working routine of base;
Fig. 6 is the process flow diagram of the survey voltage program of base;
Fig. 7 is the process flow diagram that draws inclined to one side program that enters of base.
1-ground connection alarm I pilot lamp among the figure, 2-ground connection alarm II pilot lamp, the not closed pilot lamp of 3-jaw, 4-exchanges pilot lamp, 5-direct current pilot lamp, the 6-electric current pilot lamp that transfinites, the 7-warning horn, 8-direct current split-core type meter, 9-dc system grounding emergency warning lamp, 10-withdraws from old detector emergency warning lamp, 11-exchanges and scurries into the direct current emergency warning lamp, the excessive emergency warning lamp of 12-ground capacitance, the unstable emergency warning lamp of 13-DC voltage, the 14-branch road detects the beginning emergency warning lamp, the 15-power switch, 16-straight-flow system negative busbar-KM interface, the 17-earth terminal, 18-straight-flow system positive bus-bar+KM interface, the 19-RS232 interface, 20-power equipment to be detected, 21-hand-held set and its access point, the 22-base.
Concrete enforcement
The present invention is in working order as shown in Figure 1 the time, negative supply ground connection in power equipment 20 to be detected, the faint detection electric current that sends from base 22 and comprising ground current and have again straight-flow system signal on the portable pincers type machine of transmission, detecting under the situation of fault current the valid data of the straight-flow system of can both the perception base in any one position sending.Hand-held set 21 can be judged the ground connection situation in conjunction with the informix of straight-flow system according to the detected information in locality at each access point, can remove all kinds of obstacles effectively, guarantees that detected earth fault is correctly effective.The information of the straight-flow system that fault current carries has avoided generally being subject to the characteristic signal that disturbs, and hand-held set can both detect fault current in each detection position, finds last earth point in proper order, if there is not fault current just can not alarm.
The present invention is divided into two parts; With the hand-held set of little current DC pincerlike meter and the D.C. isolation monitor base of improved single chip microcomputer.Respectively its function is described below:
One, hand-held set 21: (measurement range: 0.1mA~9.99A) and to it expand improvement, increasing with the single-chip microcomputer is the microprocessor system of core, measured direct current signal is handled, and then judged whether ground connection to utilize ready-made DC ammeter.Outside drawing is as shown in Figure 2: comprise a direct current pincerlike meter 8 and connected improved DC ammeter, improved DC ammeter pilot lamp implication is as follows:
Ground connection alarm I pilot lamp 1: single channel ground connection, show to be exactly this road ground connection, can continue down to look into down along this branch road.
Ground connection alarm II pilot lamp 2: multichannel ground connection, show that this road has outside the ground connection, also have another road ground connection simultaneously, another road may be that the parasitic loop of this branch road also may be an independent loop.Can get rid of this road ground connection earlier and look into another road,, get rid of the back this road ground connection and just recover normal naturally, if latter instance also will continue to search another road earth point after getting rid of one tunnel ground connection again if another road is a parasitic loop.
The not closed pilot lamp 3 of jaw: there is a self check electric current pincerlike meter inside, and when because jaw is not closed when tight, and detected marking current will be significantly smaller than ratings, pincerlike meter can't operate as normal under this situation, can omission ground connection branch road.When therefore this lamp was bright, the prompting staff carried out clamp again, and pincerlike meter is revised the error that each bayonet socket brings automatically by the normalized current of self check simultaneously.
Exchange pilot lamp 4: expression table meter displayed value is an alternating current.
Direct current pilot lamp 5: expression table meter displayed value is a DC current.
The electric current pilot lamp 6 that transfinites: when measuring electric current and surpass rated limits, indication gives a warning.
Warning horn 7: as long as ground connection is just alarmed (the ground connection stand by lamp is bright simultaneously), so under the simplest situation, just can continue to search down regardless of other as long as listen the loudspeaker alarm.
Two, base: base contour structures of the present invention and wiring are as shown in Figure 3, base is that a direct current insulating monitoring instrument base is made up of single chip microcomputer, basic function is identical with similar conventional insulation tester, the energy measurement busbar voltage is over against earth resistance and negative resistance to earth, over against ground voltage and negative voltage-to-ground, and show by display screen, but with conventional direct current detector has bigger difference be:
Whether base 22 can will be differentiated the original direct current detector of straight-flow system earlier and withdraw from before entering ground connection branch road searching work, as not withdrawing from, withdraw from old detector emergency warning lamp 10 and light warning, could continue after can reminding the staff to withdraw from, to prevent of the interference of old detector measuring; When owing to be to exchange to leap up when causing dc system grounding into direct current, dc system grounding emergency warning lamp 9 is scurried into direct current emergency warning lamp 11 and is lighted warning with exchanging, and will change the measurement alternating current automatically over to during split-core type meter work, enters straight-flow system to differentiate to exchange from that branch road; When ground capacitance is excessive, the excessive emergency warning lamp 12 of ground capacitance lights warning, because the rising edge that influences electric current and the negative edge of capacitor charging/discharging will slow down, specific handling procedure will be adopted to the processing of electric current in pincerlike meter inside, avoid the not obvious interference that causes of current-jump; When owing to be DC voltage when unstable, the unstable emergency warning lamp 13 of DC voltage lights warning, and split-core type meter will be automatically in the process of judging ground current carry out double measurement to signal and judge to get rid of and disturb.
Next base 22 apparatus measures DC ground resistance and voltages, and demonstration measured value.If be the negative ground connection of direct current, decision drops into positive stake resistance size according to measured value, and measure actual ground connection vagabond current and be sent to pincerlike meter by communication port.Ground current and initial value change (because stake resistance changes and causes) in testing process, and the electric current that flows through in its positive stake resistance changes automatically to be thrown the cycle that connecting resistance disconnects; Throw when straight polarity direct current ground and connect negative stake resistance, other are the same with the front.The purpose of periodically throwing connecting resistance make ground current increase to certain numerical value can be detected and produce by the direct current split-core type meter increment just with differentiation.The direct ratio that is partitioned into of the size of the positive supply supplemental current that base produces and time, pincerlike meter is determined the size of supplemental current by the time interval, and judgement is one point earth or multichannel ground connection according to the pincerlike meter plug-in.Base transmits to split-core type meter by communication port by the data that measure, and the inner microcomputer circuit of split-core type meter is stored in split-core type meter inside with this straight-flow system parameter, uses when working for split-core type meter.
The resistance value of Ra, Rb, Rc is got 100k usually during test, and the closed and disconnected of contact J1 can record four voltages: record U+ and two voltages of U-when disconnecting, record U '+and U '-two voltage when closure.So because Ra, Rb, Rc knownly can calculate R+ and R-resistance.
Foregoing circuit is the outside variable element except R+ and R-, and all the other are the inner member of base.
The base working routine in master routine, will be carried out initialization to each register during the electrification reset state as shown in Figure 5, and different deposit units needs different initial values.As timer constant initial value, cyclic constant, relay time constant etc. puts into operation.When entering ground voltage and measuring,, carry out average treatment after should adopting repeatedly image data (collection as shown in Figure 15 times), can remove a mxm. and minimum and do sums then on average for preventing to disturb the collection voltage that causes inaccurate.Electrification reset has only two states, one be the start another be just to enter when mobile phone is not worked (communication port links to each other with base) when drawing inclined to one side subroutine to judge over the ground.Base can draw the stake resistance of straight-flow system by measuring over against ground voltage and negative voltage-to-ground.Whether exist the size of AC compounent and component to judge in the straight-flow system whether leap up by measuring in the straight-flow system into AC power.The both positive and negative polarity that it is straight-flow system that measurement need not be surveyed the negative reason that exchanges over the ground over against the ground interchange is connected to electric capacity and leads directly to from exchanging equivalence principle with accumulator.
Survey the voltage program and enter and draw inclined to one side program as shown in Figure 6 and Figure 7, enter when surveying the voltage program since capacitance in certain register, the power-up initializing value equals zero, so be for the first time can not enter to exchange alarm; The overproof handling procedure of voltage is meant and handles straight-flow system because the voltage measurement error problem that ground capacitance and DC bus-bar voltage shakiness and exterior insulation monitor bring among the figure, result be draw whether have exterior insulation to monitor to insert straight-flow system, draw the ground capacitance value, how difference DC bus-bar voltage shakiness to handle.Thereby can intelligently accelerate to measure resistance to earth, get rid of the influence of ground capacitance, the unstable situation of stake resistance in the time of can differentiating DC earthing the measuring resistance accuracy.Especially hour can measure direct current resistance fast when ground capacitance, entering the effect of calculating stake resistance among the figure is exactly to judge whether at the negative resistance (whether promptly add resistance relay moves) that adds over the ground
The present invention utilizes this device just can accurately find the DC line of ground connection and can further search the concrete earth point of equipment with pincerlike meter; And need not stretching stream and just can find earth fault exactly, even charged eliminating earth fault under the situation of conditions permit at the scene; Avoid searching a series of inconvenience such as method of operation change, definite value correction and searching work time length that have a power failure and bring to the scheduling application in the ground connection working routine again, found earth point rapidly and accurately; Be applicable to electric equipment, circuit or element carry out short circuit, open circuit, the test of leakage or incorrect connection, the field of the fault in exploration cable, transmission line or the network.

Claims (4)

1. a portable intelligent DC earthing searching instrument is made up of hand-held set (21) and (22) two parts of base, it is characterized in that:
Described hand-held set (21) connects a direct current reometer by a direct current pincerlike meter (8) and forms, and base (22) is made up of the single chip microcomputer assembly;
Described single chip microcomputer assembly, it is specially a D.C. isolation monitor that single chip microcomputer is installed, and its concrete metering circuit hardware configuration is:
Resistance R+the upper end be connected with straight-flow system positive bus-bar+KM, lower end ground connection and with resistance R-the upper end be connected; Resistance R-lower end is connected with straight-flow system negative busbar-KM; These two resistance to earth that resistance is straight-flow system positive bus-bar and negative busbar;
The upper end of resistance R a is connected with straight-flow system positive bus-bar+KM, lower end ground connection and with the lower end of the upper end of resistance R b, contact J1, resistance R 2, amplifier U1+extreme, amplifier U2-upper end extreme and resistance R 3 interconnects; The lower end of resistance R b is connected and all is connected with straight-flow system negative busbar-KM with the lower end of resistance R c; The upper end of resistance R c is connected with contact J1; These 3 resistance of resistance R a, Rb and Rc are connected in order successively, form the resistance bridge that straight-flow system is measured insulation against ground resistance with the periodic closed and disconnected of contact J1 again;
The upper end of resistance R 1 is connected with straight-flow system positive bus-bar+KM, the upper end of lower end and resistance R 2 and amplifier U1-extremely be connected amplifier U1 output+signal; Resistance R 1, R2 and amplifier U1 form measurement over against the ground voltage sampling circuit;
The lower end of resistance R 3 is connected with the upper end of resistance R 4, amplifier U2+extreme the connection, amplifier U2 output-signal, the lower end of resistance R 4 is connected with straight-flow system negative busbar-KM; Resistance R 3, resistance R 4 and amplifier U2 form the negative voltage-to-ground sampling circuit of measurement;
The upper end of resistance R 5 is connected with the output positive signal end of amplifier U1, the upper end of lower end and resistance R 6, amplifier U3-extremely be connected; The output negative signal end of the lower end of resistance R 6 and amplifier U2, U3 amplifier+extremely be connected; Resistance R 5, R6 and amplifier U3 form measurement busbar voltage sampling circuit;
The left end ground connection of resistance R 7 and with amplifier U5+extremely be connected, right-hand member and amplifier U5-extremely be connected; Resistance R 7 and amplifier U5 form ground current and measure the loop;
The lower end of capacitor C is connected with straight-flow system negative busbar-KM, upper end and amplifier U4+extremely be connected; Amplifier U4-extreme ground connection; Capacitor C and amplifier U4 form dc bus alternating voltage sampling circuit;
Contact J2, the J4, the J6 that are provided with interconnect, and all with extreme being connected of right-hand member, amplifier U5-of resistance R 7, contact J2, J4, J6 also are connected with 10K, 15K, 5K resistance respectively; 10K, 15K, these 3 resistance of 5K are connected with straight-flow system positive bus-bar+KM again; These parts have been formed the incremental system that under the negative ground connection situation of straight-flow system ground connection branch road has ground current;
Contact J3, the J5, the J7 that are provided with interconnect, and are connected with straight-flow system negative busbar-KM, and contact J3, J5, J7 are connected with 10K ', 15K ', 5K ' resistance respectively again; 10K ', 15K ', 5K ' resistance also all with extreme being connected of right-hand member, amplifier U5-of resistance R 7; These parts have been formed the incremental system that under straight-flow system positive ground connection situation ground connection branch road has ground current;
Be provided with constant current source 5mA respectively at 5k and this resistance place of 5K '.
2. portable intelligent DC earthing searching instrument as claimed in claim 1, it is characterized in that: the improved DC ammeter of described hand-held set (21) part is provided with ground connection alarm I pilot lamp (1), ground connection alarm II pilot lamp (2), the not closed pilot lamp of jaw (3), exchanges pilot lamp (4), direct current pilot lamp (5), electric current transfinite pilot lamp (6), warning horn (7) on panel.
3. portable intelligent DC earthing searching instrument as claimed in claim 1 is characterized in that: described base (22) break contact J2, J3, J4, J5 directly use the contact J6 of setting and J7 ground connection to draw partially.
4. portable intelligent DC earthing searching instrument as claimed in claim 1 is characterized in that: described base (22) is provided with: dc system grounding emergency warning lamp (9), withdraw from old detector emergency warning lamp (10), exchange and to scurry into direct current emergency warning lamp (11), the excessive warning emergency warning lamp of ground capacitance (12), the unstable emergency warning lamp (13) of DC voltage, branch road and detect beginning emergency warning lamp (14), power switch (15), straight-flow system positive bus-bar+KM interface (16), earth terminal (17), straight-flow system negative busbar-KM interface (18) and RS232 interface (19).
CN200710094341XA 2007-11-30 2007-11-30 Portable intelligent DC earthing searching instrument Active CN101452034B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN200710094341XA CN101452034B (en) 2007-11-30 2007-11-30 Portable intelligent DC earthing searching instrument

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN200710094341XA CN101452034B (en) 2007-11-30 2007-11-30 Portable intelligent DC earthing searching instrument

Publications (2)

Publication Number Publication Date
CN101452034A CN101452034A (en) 2009-06-10
CN101452034B true CN101452034B (en) 2011-08-10

Family

ID=40734390

Family Applications (1)

Application Number Title Priority Date Filing Date
CN200710094341XA Active CN101452034B (en) 2007-11-30 2007-11-30 Portable intelligent DC earthing searching instrument

Country Status (1)

Country Link
CN (1) CN101452034B (en)

Families Citing this family (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102043114A (en) * 2010-10-22 2011-05-04 甘肃省电力公司金昌供电公司 Electrification loop-breaking method for direct current power supply and special device thereof
CN102004213B (en) * 2010-10-26 2013-03-13 上海天晶电力科技发展有限公司 Direct-detection type intelligent direct-current system insulation and state diagnosis instrument
CN102486496A (en) * 2010-12-03 2012-06-06 北京人民电器厂有限公司 Direct current insulation monitoring system and method capable of overcoming relay protection maloperation
CN102486518A (en) * 2010-12-03 2012-06-06 北京人民电器厂有限公司 Direct current insulation monitoring system and method capable of reducing busbar voltage fluctuation
CN103176049B (en) * 2011-12-23 2015-09-02 比亚迪股份有限公司 For circuit, apparatus and method that the insulation against ground of earth-free straight-flow system is monitored
CN103576052B (en) * 2012-08-02 2016-09-14 北京人民电器厂有限公司 Determine that alternating current seals in the system and method for DC system fault branch road
CN102944816B (en) * 2012-12-07 2016-06-22 中煤科工集团重庆研究院有限公司 Mine cable line on-line fault diagnosis and positioner
CN103472293A (en) * 2013-09-10 2013-12-25 国家电网公司 Device for detecting whether alternating currents flow into direct-current system or not
CN103760411A (en) * 2013-11-06 2014-04-30 国网安徽省电力公司淮南供电公司 Direct-current bus voltage wave-recording device
CN103698651B (en) * 2013-12-27 2016-05-11 国家电网公司 A kind ofly supervise method and the device that D.C. isolation bus is altered mutually
CN105044549B (en) * 2015-04-14 2018-04-20 广西电网有限责任公司电力科学研究院 A kind of direct current grounding trouble shooting method with self compensation electric current
CN106546871A (en) * 2015-09-18 2017-03-29 王明强 Portable DC STS system test set
CN105226341B (en) * 2015-09-18 2018-05-04 苏州工业园区职业技术学院 A kind of monitoring device in power battery production process
CN106019049A (en) * 2016-05-19 2016-10-12 国网新疆电力公司伊犁供电公司 Auxiliary device for DC grounding search of transformer station
CN106646119B (en) * 2016-11-24 2019-05-10 国网山东省电力公司成武县供电公司 Earth fault searches instrument, earth fault lookup method and system
CN107688136B (en) * 2017-07-31 2020-08-18 国网山东省电力公司电力科学研究院 Method for judging and positioning grounding point of extra-high voltage long-distance transmission line
CN108152620B (en) * 2017-12-18 2021-01-19 北京航天测控技术有限公司 Performance monitoring and analyzing instrument, system and method for electric equipment
CN108719017A (en) * 2018-04-28 2018-11-02 温州大学激光与光电智能制造研究院 Gardens automatic irrigation system
CN110635384B (en) * 2019-07-26 2021-12-28 国网浙江省电力有限公司丽水供电公司 Portable central signal screen
CN110412399A (en) * 2019-08-27 2019-11-05 中国南方电网有限责任公司超高压输电公司天生桥局 A kind of double split-core type meter formula DC earthing searching instruments
CN111413639B (en) * 2020-02-24 2022-04-01 国网浙江省电力有限公司湖州供电公司 Direct-current system insulation earth fault on-line monitoring and positioning device and method
CN111585265B (en) * 2020-06-03 2022-09-30 广东电网有限责任公司惠州供电局 Secondary equipment test power supply safe starting protection device and application
CN113702871B (en) * 2021-08-10 2024-02-06 国网河南省电力公司南阳供电公司 Intelligent line hunting device for uninterrupted secondary direct-current power supply of transformer substation

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1070486A (en) * 1992-09-21 1993-03-31 辽源电业局 DC grounding monitor alarm device
CN1078308A (en) * 1993-04-02 1993-11-10 肖战立 The lookup method of sheathed cable earth fault
CN2208709Y (en) * 1994-07-26 1995-09-27 中国矿业大学 Single-board microcomputer controlled positioning device for grounding problems
CN1580796A (en) * 2003-08-08 2005-02-16 欧姆龙株式会社 DC. detection circuit and DC. earthing current detection circuit
CN2722265Y (en) * 2004-09-17 2005-08-31 姜洪腾 DC grounding on-line tester
CN2859554Y (en) * 2005-05-11 2007-01-17 上海电力表计技术服务公司 DC ground connection fault indicator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1070486A (en) * 1992-09-21 1993-03-31 辽源电业局 DC grounding monitor alarm device
CN1078308A (en) * 1993-04-02 1993-11-10 肖战立 The lookup method of sheathed cable earth fault
CN2208709Y (en) * 1994-07-26 1995-09-27 中国矿业大学 Single-board microcomputer controlled positioning device for grounding problems
CN1580796A (en) * 2003-08-08 2005-02-16 欧姆龙株式会社 DC. detection circuit and DC. earthing current detection circuit
CN2722265Y (en) * 2004-09-17 2005-08-31 姜洪腾 DC grounding on-line tester
CN2859554Y (en) * 2005-05-11 2007-01-17 上海电力表计技术服务公司 DC ground connection fault indicator

Also Published As

Publication number Publication date
CN101452034A (en) 2009-06-10

Similar Documents

Publication Publication Date Title
CN101452034B (en) Portable intelligent DC earthing searching instrument
CN201449433U (en) Device for locating ground fault of DC system
CN203929904U (en) The charged solution loop device of a kind of straight-flow system
KR100778089B1 (en) System and method for acquiring underground lv networks configured with plural transformers in the urban area
CN105759147B (en) A kind of integrated testing device of cell management system of electric automobile
CN201130227Y (en) Portable DC earthing seeking instrument
CN106771834A (en) A kind of many DC source input wires detecting systems and photovoltaic group string formula inverter system
CN102043114A (en) Electrification loop-breaking method for direct current power supply and special device thereof
CN101968524A (en) Division test method and tester for multi-point grounding of common loop
CN106841810A (en) Insulator detector
CN101026295A (en) Non-grounding neutral point system low-voltage leakage protection method and its equipment
CN103616616B (en) Fault detection method for large-scale grounding grid
CN102004213B (en) Direct-detection type intelligent direct-current system insulation and state diagnosis instrument
CN207799007U (en) The Insulation Inspection System of the anti-reverse charge protection of direct-current charging post
CN209296853U (en) It is a kind of for detecting the circuit of multipoint earthing of iron core of transformer failure
CN208969194U (en) Novel bunk is pressed with source integral type fault locating instrument
CN205139349U (en) Arrester discharge counter and leakage current table check gauge
CN112415429B (en) Medium voltage grounding fault intelligent diagnostic instrument
CN108152692A (en) The Insulation Inspection System of the anti-reverse charge protection of direct-current charging post
CN101750540A (en) Method for detecting parasitic loop of transformer station direct current system
CN205404719U (en) Mutual -inductor common return multipoint earthing detector
CN202057749U (en) Instrument for detecting and displaying ground state of equipment or socket
CN209311572U (en) A kind of electric automobile insulation resistance detecting circuit based on Injection Signal
CN106249031A (en) Power frequency high voltage measuring device with electricity
CN106802384A (en) Electrical equipment malfunction detection method based on the sensing fusion of infrared and ultraviolet light photo

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
ASS Succession or assignment of patent right

Owner name: SHANGHAI ELECTRIC POWER CORP.

Free format text: FORMER OWNER: SHANGHAI ULTRA-HV TRANSMISSION + DISTRIBUTION COMPANY, SHANGHAI ELECTRIC POWER C

Effective date: 20110519

C41 Transfer of patent application or patent right or utility model
COR Change of bibliographic data

Free format text: CORRECT: ADDRESS; FROM: 200063 NO. 600, WUNING ROAD, PUTUO DISTRICT, SHANGHAI TO: 200122 NO. 1122, YUANSHEN ROAD, SHANGHAI

TA01 Transfer of patent application right

Effective date of registration: 20110519

Address after: 200122, 1122 deep road, Shanghai

Applicant after: Shanghai Electric Power Corporation

Address before: 200063 No. 600, Wuning Road, Shanghai, Putuo District

Applicant before: Shanghai Ultra-HV Transmission & Distribution Company, Shanghai Electric Power C

C14 Grant of patent or utility model
GR01 Patent grant
ASS Succession or assignment of patent right

Owner name: STATE ELECTRIC NET CROP.

Effective date: 20121010

C41 Transfer of patent application or patent right or utility model
TR01 Transfer of patent right

Effective date of registration: 20121010

Address after: 200122, 1122 deep road, Shanghai

Patentee after: Shanghai Electric Power Corporation

Patentee after: State Grid Corporation of China

Address before: 200122, 1122 deep road, Shanghai

Patentee before: Shanghai Electric Power Corporation