CN103995177B - The measurement of power transformer neutral point direct current and wave recording device and detection method - Google Patents

The measurement of power transformer neutral point direct current and wave recording device and detection method Download PDF

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Publication number
CN103995177B
CN103995177B CN201410162863.9A CN201410162863A CN103995177B CN 103995177 B CN103995177 B CN 103995177B CN 201410162863 A CN201410162863 A CN 201410162863A CN 103995177 B CN103995177 B CN 103995177B
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current
signal
output
fixture
circuit
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CN103995177A (en
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全江涛
邱凌
陈科基
阮羚
童歆
王亮
邓万婷
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WUHAN XINDIAN ELECTRICAL TECHNOLOGY Co Ltd
State Grid Corp of China SGCC
State Grid Hubei Electric Power Co Ltd
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WUHAN XINDIAN ELECTRICAL TECHNOLOGY Co Ltd
State Grid Corp of China SGCC
State Grid Hubei Electric Power Co Ltd
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Abstract

The measurement of described power transformer neutral point direct current and wave recording device and detection method, can be from the alternating current-direct current mixed signal of the transformer neutral point grounding flat steel of flowing through, and the record that realizes DC current involves recorder data wireless remote transmission. Device comprises voltage fixture, signal conditioning circuit, analog to digital conversion circuit, constant-current source current measurement circuit, trigger control circuit, measurement channel C PU, installs total CPU, gps clock module, GSM/GPRS communication module, controlled constant-current source, current fixture. Voltage fixture is for gathering the pressure drop on one section of grounding flat steel of transformer neutral point, through signal conditioning circuit, this voltage signal is carried out to program control amplification, and the signal after conditioning is revised, small direct current signal in the alternating current-direct current mixed signal that can flow through grounding flat steel, carries out wide region, Dynamic High-accuracy monitoring; Device can, to the generation of transforming plant DC bias phenomenon and the finish time, carry out accurate record, and connecting system network is fast realized and covered regional D.C. magnetic biasing monitoring system.

Description

The measurement of power transformer neutral point direct current and wave recording device and detection method
Technical field
While the present invention relates to a kind of large-scale power transformer running status generation D.C. magnetic biasing, convection currentMeasure and record device and the detection method of ripple through the DC current of transformer neutral point; EspeciallyRelate to one without current sensor is transformed or installed additional to transformer neutral point grounding flat steel,From the alternating current-direct current mixed signal of the grounding flat steel of flowing through, the record that realizes DC current involves record wave numberAccording to wireless remote transmitting device and detection method thereof.
Technical background
When DC power transmission line monopolar operation, around can causing to some extent, transforming plant DC is inclined to one sideMagnetic phenomenon. Transformer DC magnetic bias phenomenon can cause transformer noise aggravation, reactive loss and encourageThe problems such as magnetic current harmonic content increase, can cause Transformer Insulation Aging even to damage when seriousBad, seriously to jeopardize AC network safe operation. By the reality to transformer DC magnetic bias phenomenonIn time, monitors, and contributes to study the distribution rule of a regional alternating current-direct current mixing electrical network D.C. magnetic biasingRule, takes precautions against the adverse effect of D.C. magnetic biasing to AC network.
For the measurement of large-scale power transformer D.C. magnetic biasing, mostly adopt open-loop current to pass at presentSensor or closed loop current sensor. Open-loop current sensor aspect the measurement of DC low current,There is the performance deficiency that null offset is large; And the installation of closed loop current sensor need to have a power failureUnder state, disconnect transformer neutral point grounding flat steel. Can be to economic benefit and society's effect because have a power failureBenefit has a negative impact, so the installation current sensor that cannot have a power failure; Do not adopting electric current in additionIn the situation of sensor, from the alternating current-direct current mixed signal of the grounding flat steel of flowing through, realize DC currentRecord ripple, there is no effective means.
Summary of the invention
Object of the present invention, is to provide one and does not adopt current sensor, flat by measuring one sectionSmall electric pressure drop and resistance value on steel, can be to the alternating current-direct current hybrid current of the grounding flat steel of flowing throughRealize device and the detection method of DC current measurement and record ripple.
For reaching above object, the present invention has adopted following technical proposals:
Described power transformer neutral point direct current is measured and wave recording device comprises signal conditionCircuit, analog to digital conversion circuit, for the GSM/GPRS communication module of communication transfer, for inspectionSurvey with the measurement channel C PU controlling, install total CPU, it is characterized in that: described device also wrapsDraw together voltage fixture, constant-current source current measurement circuit, trigger control circuit, gps clock module,Controlled constant-current source, current fixture. It is flat that voltage fixture is used for gathering one section of ground connection of transformer neutral pointPressure drop on steel, carries out program control amplification through signal conditioning circuit to this voltage signal, and to conditioningAfter signal revise, output signal access analog to digital conversion circuit, and finally by measuring passageCPU completes the collection to voltage on this section of band steel; The break-make of controlled constant-current source output current byInstall total CPU and control, controlled constant-current source output current is through in current fixture access transformerOne section of band steel of property point ground connection; Constant-current source current measurement circuit is used for gathering controlled constant-current source outputActual current value, measuring channel C PU, to read constant-current source from constant-current source current measurement circuit defeatedThe actual current value going out; Trigger control circuit is for the sampled signal to signal conditioning circuit outputCompare with the reference signal of measuring channel C PU setting, produce trigger impulse and send to deviceThe external interrupt interface of total CPU, then reads current by the total CPU of device from gps clock moduleMoment.
The output of described voltage fixture is connected with the input of signal conditioning circuit, signal conditionThe output of circuit is connected with the input of analog to digital conversion circuit, analog to digital conversion circuit and constant-current sourceThe output of current measurement circuit is connected with measurement channel C PU input port; Described triggering controlThe input of circuit connects respectively signal conditioning circuit and measures an output of channel C PU, touchesSend out total CPU mono-input of control circuit output jockey; The total CPU's of described device is one defeatedGo out end and be connected with the input of controlled constant-current source, controlled constant current source output terminal is connected to electric current folderTool; Described gps clock module provides clock signal, GSM/GPRS communication for installing total CPUModule is connected with both-way communication form with the total CPU of device; The total CPU of described device and measurement passageCPU is connected.
The total CPU of described device controls controlled constant-current source electric current output, output current current fixtureBe connected to one section of band steel of transformer neutral point ground connection; Measuring channel C PU surveys from constant-current source electric currentAmount circuit reads the actual current value of controlled constant-current source output; Measuring channel C PU presss from both sides by voltageTool, signal conditioning circuit and analog to digital conversion circuit are measured the electricity on band steel between two voltage fixturesPressure value, measures and control operation through continuous quadratic, realizes band steel electricity between nominal voltage fixtureResistance function.
Voltage fixture and current fixture are aluminium alloy workpiece, and two voltage fixtures are arranged on electric currentFixture inner side, is used outer-hexagonal brass bolt by fastening to fixture and transformer neutral point grounding flat steel,Make all fixtures and band steel contact-making surface impedance minimum.
Analog to digital conversion circuit adopts a kind of integration type A/D, by adjusting input A/D chip timeClock frequency, is consistent the time of integration of A/D chip and power frequency period, realizes input letterThe inhibition of power frequency and higher hamonic wave composition thereof in number.
In technique scheme, install total CPU and GSM/GPRS communication module carries out two-wayCommunication, realizes wave recording device network communication and function of receiving and sending short message; Described gps clock module isInstall total CPU clock signal is provided.
The present invention adopts technique scheme, has following effect and advantage:
1) in the project implementation process, without having a power failure to the transformation of transformer neutral point grounding flat steel or installing additionalCurrent sensor;
2) the small direct current signal in the alternating current-direct current mixed signal that can flow through grounding flat steel, carries out wideScope, Dynamic High-accuracy monitoring;
3) device can, to the generation of transforming plant DC bias phenomenon and the finish time, accurately be rememberedRecord;
4) after device is installed, connecting system network fast, it is inclined to one side that realization covers regional direct currentMagnetic monitoring system.
5) monitored data contributes to study the distribution of a regional alternating current-direct current mixing electrical network D.C. magnetic biasingRule, takes precautions against the adverse effect of D.C. magnetic biasing to AC network.
Brief description of the drawings
Fig. 1 is block diagram of the present invention;
Fig. 2 is band steel fixture installation diagram of the present invention;
Fig. 3 is the scaling method figure of the tested band steel resistance R of the present invention x.
Wherein: 1-voltage fixture, 2-signal conditioning circuit, 3-analog to digital conversion circuit, 4-Constant-current source current measurement circuit, 5-trigger control circuit, 6-measurement channel C PU, 7-dressPut total CPU, 8-gps clock module, 9-GSM/GPRS communication module, 10-controlledConstant-current source, 11-current fixture, 12-transformer neutral point grounding flat steel.
Detailed description of the invention
Below in conjunction with accompanying drawing and example, the present invention is described in further detail:
One, general structure
As shown in Figure 1. Described power transformer neutral point direct current is measured and wave recording device,Comprise signal conditioning circuit 2, analog to digital conversion circuit 3, logical for the GSM/GPRS of communication transferNews module 9, for detection of with control measurement channel C PU6, install total CPU7, its featureBe: described device also comprises voltage fixture 1, constant-current source current measurement circuit 4, triggers controlCircuit 5 processed, gps clock module 8, controlled constant-current source 10, current fixture 11. Voltage fixture1 for gathering the pressure drop on one section of grounding flat steel 12 of transformer neutral point, through signal condition electricityProgram control amplification is carried out to this voltage signal in road 2, and the signal after conditioning is revised, outputSignal access analog to digital conversion circuit 3, and finally complete this section of band steel by measuring channel C PU6The collection of upper voltage; The break-make of controlled constant-current source 10 output currents is controlled by installing total CPU7,Controlled constant-current source 10 output currents access one of transformer neutral point ground connection through current fixture 11Section band steel 12; The reality that constant-current source current measurement circuit 4 is exported for gathering controlled constant-current source 10Border current value, measures channel C PU6 and reads constant-current source output from constant-current source current measurement circuit 4Actual current value; The sampling letter of trigger control circuit 5 for signal conditioning circuit 2 is exportedNumber compare with measuring the reference signal that channel C PU6 arranges, produce trigger impulse and send toInstall the external interrupt interface of total CPU7, then by installing total CPU7 from gps clock module 8Read current time.
In Fig. 1, the input of the output of described voltage fixture 1 and signal conditioning circuit 2Be connected, the output of signal conditioning circuit 2 is connected with the input of analog to digital conversion circuit 3, mouldThe output of number conversion circuit 3 and constant-current source current measurement circuit 4 is defeated with measurement channel C PU6Inbound port is connected; The input of described trigger control circuit 5 is connected with respectively signal conditioning circuit2 and measure an output of channel C PU6, trigger control circuit 5 output jockeys are totalCPU7 mono-input; An output of the total CPU7 of described device and controlled constant-current source 10 defeatedEnter end and be connected, controlled constant-current source 10 outputs are connected to current fixture 11; Described gps clockModule 8 provides clock signal for installing total CPU7, and GSM/GPRS communication module 9 is total with deviceCPU7 is connected with both-way communication form; The total CPU7 of described device is connected with measurement channel C PU6.
The total CPU7 of described device controls controlled constant-current source 10 electric current outputs, output current electric currentFixture 11 is connected to one section of band steel of transformer neutral point ground connection; Measure channel C PU6 from constant currentSource current measurement circuit 4 reads the actual current value that controlled constant-current source 10 is exported; Measure passageCPU6 measures two electricity by voltage fixture 1, signal conditioning circuit 2 and analog to digital conversion circuit 3Press the magnitude of voltage on band steel between fixture 1, measure and control operation through continuous quadratic, realizeBand steel resistance value function between nominal voltage fixture 1.
Analog to digital conversion circuit 3 adopts a kind of integration type A/D, inputs A/D chip by adjustingClock frequency, is consistent the time of integration of A/D chip and power frequency period, realizes inputThe inhibition of power frequency and higher hamonic wave composition thereof in signal.
Fig. 2 is band steel fixture installation diagram, and voltage fixture 1 and current fixture 11 add for aluminium alloyWorkpiece, good conductivity, material is lightweight; Voltage fixture 1 and current fixture 11 inner spacesAbundant, adapt to multi-thickness and width band steel installation requirement; When fixture is installed, inner side under fixtureFace and transformer grounding band steel 12 are fitted completely, and on fixture, medial surface is by outer-hexagonal brass boltBy fastening to fixture and transformer grounding band steel 12, above-mentioned mounting process makes fixture contact with band steelFace impedance minimum. Two voltage fixtures 1 are arranged on current fixture 11 inner sides, reduce fixture withThe impact of band steel contact resistance on current measurement precision.
Two, operation principle of the present invention and function realize:
The present invention is a kind of without transformer neutral point grounding flat steel being transformed or installed additional electric current biographySensor, can, from the alternating current-direct current mixed signal of the grounding flat steel of flowing through, realize the record of DC currentInvolve the device of recorder data wireless remote transmission.
Wave recording device is chosen a section of transformer neutral point grounding switch below by voltage fixtureBand steel is made sample resistance. When measured DC flows through band steel, will on this section of band steel, produce pressureFall, according to Ohm's law, calculate the DC current flowing through on band steel.
First need the voltage producing on measuring transformer neutral ground band steel. Device first passes throughSignal conditioning circuit carries out offset voltage correction, program control amplification to voltage signal, by signal amplitudeConditioning is to analog to digital conversion circuit linear zone. Secondly this voltage is alternating current-direct current mixed signal, for realizingTo the inhibition of power frequency in signal and higher hamonic wave composition thereof, the analog to digital conversion circuit in device adoptsA kind of integration type A/D, inputs the clock frequency of A/D chip by adjusting, by A/D chipThe time of integration and power frequency period are consistent. Because power frequency and higher hamonic wave thereof are to change in the cycleSignal, the positive and negative area under the curve of signal equates, after power frequency and the conversion of higher hamonic wave signal integration thereofBe zero, direct current is the cumulative sum of signal amplitude in the time of integration.
One section of band steel resistance R x of its less important measuring transformer neutral ground. The demarcation side of RxMethod is as shown in Figure 3: measure for the first time and turn-off controlled constant-current source output, between measuring voltage fixtureBand steel pressure drop is U1, wherein U1=I0Rx; And then under equal conditions connect controlled constant currentSource electric current I s measures for the second time, on this section of band steel, is now I by electric current0+ Is, recordsBetween voltage fixture, band steel pressure drop is U2, U2=(I0+ Is) Rx. Two equatioies subtract each other, canObtain Rx=(U2-U1)/Is。
Trigger control circuit is to the analog signal of signal conditioning circuit output and measurement channel C PUThe triggering reference signal arranging compares, filtering and shaping, the triggering arteries and veins of outputting standard pulsewidthPunching. Comparator output rising edge generates D.C. magnetic biasing relevant triggering signal occurs, and trailing edge is rawBecome D.C. magnetic biasing to finish relevant triggering signal.
Further, the millisecond timer that installs total CPU inside carries out 1 millisecond of counting, usesThe pulse per second (PPS) rising edge of gps clock module output carries out timing zero clearing to count value. When receivingWhen the generation of D.C. magnetic biasing or end trigger signal, will be in the total CPU external interrupt service of device journeyIn order, read the millisecond value that count value occurs as event this moment, and from gps clock module stringLine interface reads the Hour Minute Second of event. By with upper type, realize D.C. magnetic biasing is occurred and knotThe accurate record in bundle moment.
By integrated GSM/GPRS module, utilize and cover nationwide wireless network, realizeThe deployment of the long-range access network of wave recording device.

Claims (5)

1. power transformer neutral point direct current is measured and a wave recording device, comprises signalModulate circuit (2), analog to digital conversion circuit (3), for the GSM/GPRS communication of communication transferModule (9), for detection of with control measurement channel C PU (6), install total CPU (7),It is characterized in that: described device also comprise voltage fixture (1), constant-current source current measurement circuit (4),Trigger control circuit (5), gps clock module (8), controlled constant-current source (10) and electric current folderTool (11); Voltage fixture (1) is for gathering the pressure on one section of grounding flat steel of transformer neutral pointFall, through signal conditioning circuit, this pressure drop signal is carried out to program control amplification, and to the signal after conditioningRevise, output signal access analog to digital conversion circuit, and finally complete by measuring channel C PUTo the collection of voltage on this section of band steel; The break-make of controlled constant-current source (10) output current is by installingTotal CPU controls, and controlled constant-current source output current is through in current fixture (11) access transformerOne section of band steel of property point ground connection; Constant-current source current measurement circuit (4) is for gathering controlled constant currentThe actual current value of source output, measures channel C PU and reads controlled from constant-current source current measurement circuitThe actual current value of constant-current source output; Trigger control circuit (5) is for to signal conditioning circuitThe sampled signal of output compares with the reference signal of measuring channel C PU setting, produces and triggersPulse sends to the external interrupt interface of the total CPU of device, then by the total CPU of device during from GPSClock module reads current time;
The output of described voltage fixture (1) is connected with the input of signal conditioning circuit (2),The output of signal conditioning circuit (2) is connected with the input of analog to digital conversion circuit (3), mouldThe output of number conversion circuit (3) and constant-current source current measurement circuit (4) and measurement passageCPU (6) input port is connected; The input of described trigger control circuit (5) connects respectivelyThere is an output of signal conditioning circuit (2) and measurement channel C PU (6), trigger and control electricityTotal CPU (7) one inputs of road (5) output jockey; The total CPU of described device (7)An output be connected with the input of controlled constant-current source (10), controlled constant-current source (10) is defeatedGo out end and be connected to current fixture (11); When described gps clock module provides for installing total CPUClock signal, GSM/GPRS communication module (9) and the total CPU of device (7) are with both-way communication formBe connected; The total CPU of described device (7) is connected with measurement channel C PU (6).
2. power transformer neutral point direct current according to claim 1 is measured and recordWave apparatus, is characterized in that: the total CPU of described device (7) controls controlled constant-current source (10)Electric current output, current fixture for output current (11) is connected to one of transformer neutral point ground connectionSection band steel; Measure channel C PU (6) and read controllable constant from constant-current source current measurement circuit (4)The actual current value of stream source (10) output; Measure channel C PU (6) by voltage fixture (1),Signal conditioning circuit (2) and analog to digital conversion circuit (3) measure two voltage fixtures (1) itBetween magnitude of voltage on band steel, measure and control operation through continuous quadratic, realize nominal voltage folderBand steel resistance value function between tool (1).
3. power transformer neutral point direct current according to claim 1 is measured and recordWave apparatus, is characterized in that: voltage fixture (1) and current fixture (11) add for aluminium alloyWorkpiece, two voltage fixtures (1) are arranged on current fixture (11) inner side, use outer-hexagonalBrass bolt, by fastening to fixture and transformer neutral point grounding flat steel, connects all fixtures and band steelTouch face impedance minimum.
4. power transformer neutral point direct current according to claim 1 is measured and recordWave apparatus, is characterized in that: analog to digital conversion circuit (3) adopts a kind of integration type A/D chip,Input the clock frequency of A/D chip by adjusting, by the time of integration of A/D chip and power frequency weekPhase is consistent, and realizes the inhibition to power frequency in input signal and higher hamonic wave composition thereof.
5. the detection for the measurement of power transformer neutral point direct current and wave recording deviceMethod, is characterized in that carrying out as follows:
The voltage producing on a measuring transformer neutral ground band steel, passes through signal conditioning circuitVoltage signal is carried out to offset voltage correction, program control amplification, signal amplitude is nursed one's health to modulus and turnChange circuit linear zone, adopt integration type A/D analog to digital conversion circuit, adjusting input A/D chipClock frequency, is consistent the time of integration of A/D chip and power frequency period, to realize instituteThe inhibition of power frequency and higher hamonic wave composition thereof in this signal gathering;
One section of band steel resistance R x of b measuring transformer neutral ground, the scaling method of Rx asUnder: measure for the first time and turn-off controlled constant-current source output, between measuring voltage fixture, band steel pressure drop isU1, wherein U1=I0Rx, I in formula0Controlled constant-current source output current when measuring for the first time;And then under equal conditions connect controlled constant-current source electric current I s and measure for the second time, nowOn this section of band steel, be I by electric current0+ Is, recording band steel pressure drop between voltage fixture is U2,U2=(I0+ Is) Rx, two equatioies subtract each other, and obtain Rx=(U2-U1)/Is;
C trigger control circuit is to the analog signal of signal conditioning circuit output and measurement channel C PUThe triggering reference signal arranging compares, filtering and shaping, the triggering arteries and veins of outputting standard pulsewidthPunching, comparator output rising edge generates D.C. magnetic biasing relevant triggering signal occurs, and trailing edge is rawBecome D.C. magnetic biasing to finish relevant triggering signal;
The millisecond timer of the total CPU of d device inside carries out 1 millisecond of counting, uses gps clockThe pulse per second (PPS) rising edge of module output carries out timing zero clearing to count value, when receiving D.C. magnetic biasingGeneration or when end trigger signal, will, in the total CPU external interrupt service routine of device, readGet the millisecond value that count value occurs as event this moment, and read from gps clock module serial line interfaceGet the Hour Minute Second of event, realize D.C. magnetic biasing generation and the accurate record of the finish time;
E, by integrated GSM/GPRS module, utilizes and covers nationwide wireless network, realThe deployment of the existing long-range access network of wave recording device.
CN201410162863.9A 2014-04-22 2014-04-22 The measurement of power transformer neutral point direct current and wave recording device and detection method Active CN103995177B (en)

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CN108152559A (en) * 2017-12-23 2018-06-12 中国西电电气股份有限公司 A kind of integrated DC magnetic bias current measuring device and method
CN109116169A (en) * 2018-08-03 2019-01-01 西南交通大学 The detection and analysis device and its determination method of power transformer D.C. magnetic biasing
CN110824226A (en) * 2019-10-17 2020-02-21 深圳供电局有限公司 Direct current measuring method, device and system

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2731077A1 (en) * 1995-02-23 1996-08-30 Sarl Digital Way Three=phase network parameters, such as voltage, current, phase and frequency measuring appts.
CN101236224A (en) * 2007-12-24 2008-08-06 国网直流工程建设有限公司 Converter transformer DC magnetic bias electrical current practical test method
CN101241156A (en) * 2007-12-05 2008-08-13 国网直流工程建设有限公司 Method for loading direct current mutual-inductor for applying to converter transformer bias magnet monitoring
CN101551440A (en) * 2009-05-15 2009-10-07 东北大学 Generator transformer unit faults recorder analysis device
CN101667779A (en) * 2008-09-03 2010-03-10 华东电力试验研究院有限公司 Bias magnetic power supply device for detecting capacity of bearing direct current bias magnet of transformer
EP1397693B1 (en) * 2001-06-08 2010-06-09 Eaton Electric Limited Measuring devices
CN102411084A (en) * 2011-07-26 2012-04-11 东北电力科学研究院有限公司 Online monitoring device and method of grounding current of iron core of transformer
CN102522819A (en) * 2011-11-24 2012-06-27 浙江省电力公司 Record wave pattern modeling method for fault record device of intelligent transformer substation
CN203133146U (en) * 2013-03-21 2013-08-14 国家电网公司 Transformer neutral point current measuring device

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2731077A1 (en) * 1995-02-23 1996-08-30 Sarl Digital Way Three=phase network parameters, such as voltage, current, phase and frequency measuring appts.
EP1397693B1 (en) * 2001-06-08 2010-06-09 Eaton Electric Limited Measuring devices
CN101241156A (en) * 2007-12-05 2008-08-13 国网直流工程建设有限公司 Method for loading direct current mutual-inductor for applying to converter transformer bias magnet monitoring
CN101236224A (en) * 2007-12-24 2008-08-06 国网直流工程建设有限公司 Converter transformer DC magnetic bias electrical current practical test method
CN101667779A (en) * 2008-09-03 2010-03-10 华东电力试验研究院有限公司 Bias magnetic power supply device for detecting capacity of bearing direct current bias magnet of transformer
CN101551440A (en) * 2009-05-15 2009-10-07 东北大学 Generator transformer unit faults recorder analysis device
CN102411084A (en) * 2011-07-26 2012-04-11 东北电力科学研究院有限公司 Online monitoring device and method of grounding current of iron core of transformer
CN102522819A (en) * 2011-11-24 2012-06-27 浙江省电力公司 Record wave pattern modeling method for fault record device of intelligent transformer substation
CN203133146U (en) * 2013-03-21 2013-08-14 国家电网公司 Transformer neutral point current measuring device

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
基于变压器中性点电流的在线监测系统的研究;完泾平 等;《电力设备》;20081130;第9卷(第11期);第33-35页 *
采用交流互感器测量变压器中性点直流分量的方法;张红跃 等;《电力系统保护与控制》;20130816;第41卷(第16期);第97-102页 *

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