CN1603852A - Excitation characteristic test system for current transformer - Google Patents
Excitation characteristic test system for current transformer Download PDFInfo
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- CN1603852A CN1603852A CN 200410067566 CN200410067566A CN1603852A CN 1603852 A CN1603852 A CN 1603852A CN 200410067566 CN200410067566 CN 200410067566 CN 200410067566 A CN200410067566 A CN 200410067566A CN 1603852 A CN1603852 A CN 1603852A
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Abstract
It is a current transformer excitation test system in electric power test technique field, wherein the power system comprises bridge rectification module, filter capacitor and start protection circuit; the data collection system comprises current sensor, voltage sensor, isolation module, temperature sensor, temperature transducer and analog channel of data collection card; the control sub-system comprises digit output channel of data collection card, three solid relays, three electromagnetic relays, and three contactors; the central processor is connected with data collection system and control sub-system through data collection card.
Description
Technical field
What the present invention relates to is a kind of excitation characteristic test system for current transformer, and particularly a kind of test macro that is used for power current transformer Secondary Winding excitation property is used for the power test technical field.
Background technology
The excitation property of the Secondary Winding of current transformer is the key factor of decision mutual inductor performance, thus in the middle of the engineering practice excitation property of the Secondary Winding of current transformer is measured essential.According to GB GB16847-1997 " technical requirement of protective current transformer, transient characterisitics ", the performance index of weighing the mutual inductor Secondary Winding have a lot.Wherein outbalance has parameters such as winding current and magnetic flux relation, winding voltage and current relationship, remanent magnetism coefficient, winding internal resistance, linear inductance.The measuring process of these parameters is often very complicated and loaded down with trivial details, and testing tool function singleness in the past, and complicated operation need more subsequent treatment work.Obtaining of the measurement of these parameters and curve can not all realize in the middle of one-shot measurement, therefore is difficult to satisfy modern quick production requirement.Mention in GB GB16847-1997, the test philosophy that traditional proving installation adopts mainly contains low-frequency ac method, DC-method and capacity discharge method.
Find by prior art documents; mention in publication " transient protection mutual inductor transient state winding excitation property and remanent magnetism test " literary composition on " High-Voltage Technology " the 26th volume third phase 2000.6; the supply unit of high capacity costliness be need adopt based on the proving installation of low-frequency ac method, system complex, cost of development height made.And adopting the proving installation of traditional DC-method, the electric current in the Secondary Winding discharge process to change slowly, electric current can not reach zero point in the short time, so the measurement of remanent magnetism coefficient can not accurately obtain.And when the winding discharge process begins, can produce the voltage jump phenomenon at the winding two ends, this is very disadvantageous for the voltage sensor that is connected on its two ends, promptly requires voltage sensor that very high withstand voltage and very wide frequency individual features is arranged.For TPY level current transformer, its remanent magnetism is low usually can be ignored, and for TPS and TPX electrode current mutual inductor, because remanent magnetism coefficient height needs to carry out the iron core demagnetization before each test.Therefore in excitation property is measured, need extra demagnetization treatment process one, bring very big inconvenience to test.In addition, more than all be difficult for recording the winding internal resistance in the device, need additional testing.
Summary of the invention
The objective of the invention is to overcome deficiency of the prior art, a kind of excitation characteristic test system for current transformer is provided, make its complexity that has overcome the traditional test device, Keep Clear-High Voltage test status, be a kind of application multi-functional with low cost that can measure multiple parameter and curve test macro easily.
The present invention is achieved by the following technical solutions, comprising: power-supply system, measurement major loop, data acquisition system (DAS), control subsystem, central processing unit system and peripheral common apparatus.Its annexation is: power-supply system is connected by control subsystem with the measurement major loop, measures major loop and central processing unit system and then is linked together by data acquisition system (DAS).Peripheral common apparatus then links together with central processing unit system data input, output function is provided.
Power-supply system is made up of full-bridge rectification module, filter capacitor and startup holding circuit.The function of power-supply system is to be responsible for 220VAC, and the alternating current of 50Hz transforms into exciting direct current.The input end of full-bridge rectification module applies 220VAC, the alternating current of 50Hz, and start holding circuit indirectly at two lead-out terminal.Start the big electric current generation that the anti-locking system of holding circuit powers up moment suddenly.And then start holding circuit connection filter capacitor and carry out Filtering Processing, to reduce power-supply ripple.
Measure major loop by damping resistance R
D, parallel resistance Rp, shunt capacitance Cp, tested winding form.Parallel resistance Rp, shunt capacitance Cp and tested winding parallel connection, a damping resistance R on this basis again contacts
DConstituted this and measured the critical piece of major loop, other detection part then carries out data acquisition to the point of the respective detection in this major loop.The function of measuring major loop is to constitute the test charging and discharging circuit.
Data acquisition system (DAS) is made up of the analog channel of current sensor, voltage sensor, isolation module, temperature sensor, temperature transmitter and data collecting card.The function of data acquisition system (DAS) is to gather voltage, current signal and the environment temperature of measuring the central tested winding of major loop.The input end of current sensor is chained together with the tested winding of measuring in the major loop, realizes the measurement of tested winding electric flow.And the input end of voltage sensor and tested winding are connected in parallel, and realize the measurement of tested winding voltage amount.The lead-out terminal of current sensor and voltage sensor is connected with the input terminal of two isolation modules respectively, to realize the isolation of system's strong power part and weakness part.The lead-out terminal of two isolation modules then connects two analog input channels of data collecting card respectively.Temperature sensor is used to gather environment temperature, and temperature sensor is standard thermal resistance PT100, and it connects the resistance input terminal of temperature transmitter.The measuring resistance of connecting in the electric power loop of temperature transmitter, and the signal of this standard resistor at two terminals is sent to another analog quantity channel of data collecting card.
Control subsystem is made up of data acquisition card digital amount output channel, solid-state relay, electromagnetic relay, contactor.Data acquisition card digital amount output channel comprises that test control DO0, winding are oppositely controlled DO1, main power switch is controlled DO2.Solid-state relay comprises that primary power control SSR1, winding are oppositely controlled SSR2, SSR3 is controlled in test.Electromagnetic relay comprises that primary power control KM1, winding are oppositely controlled KM2, KM3 is controlled in test.Contactor comprises main power switch KS1, winding reverser KS2, Test Switchboard KS3.The input terminal that the output of three digital quantities DO2, the DO1 of data collecting card, DO0 connect three solid-state relay SSR1, SSR2, SSR3 respectively, and the lead-out terminal of three solid-state relay SSR1, SSR2, SSR3 is cascaded with the coil of three electromagnetic relay KM1, KM2, KM3 respectively and is connected in the power supply of 24VDC.The normally opened contact of three electromagnetic relay KM1, KM2, KM3 is cascaded with the coil of three contactor KS1, KS2, KS3 respectively and is connected in 220VAC, the 50Hz power supply.The function of control subsystem is to constitute gauge tap and the corresponding isolated drive circuit of measuring major loop.
Central processing unit system is made of the industrial control computer that has the isa bus expansion slot.Move Windows on it, had friendly control interface.Its function is to realize central computing and logic control task.By the control function of the multi-functional ISA data collecting card realization on the control isa bus expansion slot to data acquisition system and control subsystem.
Peripheral common apparatus is made up of a printer, LCD, operation keyboard and a mouse.It is responsible for demonstration, the printing function of system's man-machine interaction and measured parameter and curve.
The main power switch KS1 of control subsystem is 220VAC, and alternating current and the power-supply system of 50Hz link together.The Test Switchboard KS3 of control subsystem connects power-supply system and measures major loop.And tested winding is to be connected in by the reverse gauge tap KS2 of the winding of control subsystem to measure in the middle of the major loop, belongs to a part of measuring major loop.Three contactless contactor functions are respectively: main power switch KS1 is responsible for connecting the excitation primary power, and is ready for testing; Winding reverser KS2 is responsible for the reversal connection of test winding, realizes the forward and reverse test to winding; Test Switchboard KS3 is responsible for switching on and off test process.Total system is by the central processing unit system centralized control, and central processing unit system is according to the logical order of strictness and the action of time interval Coordination Treatment power-supply system, measurement major loop, data acquisition system (DAS), control subsystem and peripheral common apparatus.
The present invention compared with prior art, have the following advantages: (1) has adopted virtual instrument technique based on industrial control computer, the software and hardware advantage of performance computing machine, realize data automatic collecting, analysis and processing, broken through the limitation of traditional instrument in measuring speed, function and accommodation.(2) linear inductance, remanent magnetism coefficient, winding internal resistance, the voltage-to-current relation curve to secondary winding in current transformer, the measurement of magnetic flux-current relationship curve in the middle of test once, have been realized.(3) do not need extra special demagnetization measure, promptly realized that by the positive and negative alternate excitation measurement demagnetization is integrated.And the desirable mean value of repeatedly measuring has reduced error immediately, has improved precision.(4) the DC-method test loop B3 that GB is recommended has carried out simple transformation, promptly at tested winding side big electric capacity in parallel, improve voltage, the current waveform of tested winding, make that change in voltage slows down in the discharge process, and make electric current change zero crossing within a short period of time.Guaranteed finite process integral time like this, made that the measurement of remanent magnetism coefficient is more accurate tested winding voltage.(5) by the break-make control to Test Switchboard, making increases corresponding stable state section in tested winding voltage, the electric current change curve, realized the internal resistance measurement of winding.And, realized that the winding internal resistance is to the automatic conversion of 75 ℃ of internal resistances of standard under the environment temperature by the on-line measurement of environment temperature.(6) have demonstration and printing, form editor and the printing function of exciting characteristic curve.(7) having test data preserves and the historical record query function.
Description of drawings
Fig. 1 system chart of the present invention
Fig. 2 test sequence figure of the present invention
Fig. 3～6 test procedure process flow diagram of the present invention
Fig. 7 circuit diagram of the present invention
Embodiment
As shown in Figure 1, excitation characteristic test system for current transformer comprises: power-supply system, measurement major loop, data acquisition system (DAS), control subsystem, central processing unit system and peripheral common apparatus.Power-supply system is made up of full-bridge rectification module, filter capacitor and startup holding circuit.Two lead-out terminals of full-bridge rectification module connect the startup holding circuit, and the output that starts holding circuit connects filter capacitor; Measure major loop by damping resistance R
D, parallel resistance Rp, shunt capacitance Cp, tested winding form, parallel resistance Rp, shunt capacitance Cp and tested winding parallel connection, a damping resistance R on this basis again contacts
DData acquisition system (DAS) is by current sensor, voltage sensor, isolation module, temperature sensor, the analog channel of temperature transmitter and data collecting card is formed, the input end of current sensor is chained together with the tested winding of measuring in the major loop, the input end of voltage sensor and tested winding are connected in parallel, the lead-out terminal of current sensor and voltage sensor is connected with the input terminal of two isolation modules respectively, the lead-out terminal of two isolation modules then connects two analog input channels of data collecting card respectively, temperature sensor connects the resistance input terminal of temperature transmitter, the measuring resistance of connecting in the electric power loop of temperature transmitter, and the signal of this standard resistor at two terminals is sent to another analog quantity channel of data collecting card; Control subsystem is made up of the digital quantity output channel of multifunctional data acquisition card, three solid-state relays, three electromagnetic relays, three contactors, the digital quantity output channel of multifunctional data acquisition card comprises three tunnel outputs, amplify through the isolation of three solid-state relays and three electromagnetic relays respectively and send into three contactless contactors, with the control survey major loop.Central processing unit system is made up of an industrial control computer, and central processing unit system connects data acquisition system (DAS) and control subsystem by multifunctional data acquisition card, and simultaneously, it is connected with peripheral common apparatus.
In control subsystem, the digital quantity output channel of multifunctional data acquisition card comprises test control DO0, winding is oppositely controlled DO1, main power switch control DO2, three solid-state relays are primary power control SSR1, winding is oppositely controlled SSR2, test control SSR3, three electromagnetic relays are primary power control KM1, winding is oppositely controlled KM2, test control KM3, three contactors are main power switch KS1, winding reverser KS2, Test Switchboard KS3, data acquisition card digital amount output DO2, DO1, DO0 connects solid-state relay SSR1 respectively, SSR2, the input terminal of SSR3, and solid-state relay SSR1, SSR2, the lead-out terminal of SSR3 respectively with electromagnetic relay KM1, KM2, the coil of KM3 is cascaded and is connected in the power supply of 24VDC, electromagnetic relay KM1, KM2, the normally opened contact of KM3 respectively with contactor KS1, KS2, the coil of KS3 is cascaded and is connected in 220VAC, the 50Hz power supply.
The main power switch KS1 of control subsystem connects 220VAC, the alternating current of 50Hz and power-supply system, the Test Switchboard KS3 of control subsystem connects power-supply system and measures major loop, and the reverse gauge tap KS2 of the winding of control subsystem connects measurement major loop and tested winding.
Central processing unit system is made of the industrial control computer that has the isa bus expansion slot, has moved Windows on it, by the control of the multi-functional ISA data collecting card realization on the control isa bus expansion slot to data acquisition system and control subsystem.
Peripheral common apparatus is made up of a printer, LCD, operation keyboard and a mouse.
Embodiment below is provided:
Adopt virtual instrument technique, when implementing, adopt the isa bus multi-functional data card of an integrated analog data acquisition function and digital quantity output control function, it is inserted on the isa bus expansion slot of moving the industrial control computer that Windows and integrated circuit board driver are arranged, realizes all control function and data acquisition function by applicating software programming in computer-internal.Promptly replaced a lot of hardware design, made system neatly effective with software programming.The isa bus multi-functional data card of collection analog data acquisition used herein and digital quantity output control function is a PCL-818L data collecting card.It provides, and five kinds of measurements commonly used and control function: A/D conversion, D/A conversion, digital quantity input, digital quantity are exported, timer/timer function.8 passage difference analog quantitys inputs, TTL compatible, A/D converter resolution are 12, and precision is 0.01%, and high sampling rate can reach 40KHz.Native system adopts difference analogue amount input mode, always has 3 analog quantitys inputs, is respectively tested winding both end voltage AI0, tested winding current AI1, just send the temperature signal A I2 of device from temperature.The input range of each passage is ± 10V that sampling rate is 3KHz.Data mode is selected for use and is interrupted transmitting, and produces an interruption in data of every sampling, and interrupt routine is delivered to data in the buffer zone of distributing in advance.Utilize the digital quantity of integrated circuit board to export the control that the DO function has realized three-way switch.Among Fig. 7, the S switch is the master switch of system start-up; PCL818L is a data collecting card, difference input 0～10V; KS1, KS2, KS3, KS4 are contactor; KM1, KM2, KM3, KM4 are electromagnetic relay; SSR1, SSR2, SSR3 are solid-state relay; Signal DO0, DO1, D02 are three digital quantity outputs of data collecting card; ISO1, ISO2 are isolation module; HSY is a current sensor; HNV is a voltage sensor; Rp is a parallel resistance, 100 Ω, 2800W; Cp is shunt capacitance 1500 μ F, 450V; R
DBe damping resistance, 30 Ω, 900W; C is filter capacitor 4500 μ F, 450V; R1 is for starting protection divider resistance 2.3K Ω, 100W; R2 is for starting protection resistance in series 20 Ω, 600W; R
KM4Be relay K M4 internal resistance 100 Ω; SBWZ is a temperature transmitter; PT100 is a temperature sensor;
After having possessed aforesaid hardware condition, by industrial control computer is programmed, realization is controlled the data capture card, total system is moved according to following logical order, finish corresponding data acquisition and processing procedure: 1) industrial control computer control data capture card carries out the ambient temperature signal collection, deposits temperature data in calculator memory.2) industrial control computer control data capture card output main power switch control signal is connected main power switch KS1.3) computer control data collecting card output winding reverser control signal is tested winding reversal connection.4) computer control data collecting card output test control signal is connected Test Switchboard KS3.At this moment fail to be convened for lack of a quorum through the direct current of overcommutation and filtering tested winding is carried out excitation.Respectively the voltage and current signal of the tested winding in the excitation process is gathered in real time by voltage sensor and current sensor, reached stable state up to this charging process.5) computer control data collecting card output test control signal disconnects Test Switchboard KS3.At this moment direct supply is cut off, and parallel resistance Rp and Cp and tested winding have constituted an independently discharge loop, produces a discharge transient process, and data collecting card is gathered the voltage and current signal of this discharge process, finishes up to discharge process.6) whether the check measurement number of times has reached the specifying measurement number of times.If then enter the 7th) step.Otherwise, turn back to the 3rd) and step continuation test.7) computer control data collecting card output power off signal disconnects main power switch KS1.8) industrial control computer to voltage, electric current and the temperature signal that collects convert, processing procedures such as mistake detection, filtering and numerical evaluation draw expection measured parameter and curve, and printing test form and exciting characteristic curve as required.Fig. 2 has described the action logic and the data acquisition of each switch in the middle of one-shot measurement, wherein the specifying measurement number of times is decided to be 4, the user can be provided with this number (should be even number, because even number can guarantee that all switch coils are in not electriferous state when one-shot measurement finishes) as required flexibly.In Fig. 3～6, the test procedure flow process of central processing unit system inside is divided into four modules, and they are respectively parameter calculating module, data acquisition module, main test module, data processing module.Call relation between them is: main test module calls data acquisition module and data processing module successively, and data processing module is the call parameters computing module again.Main test module is realized the macro-control of measurement and computing, and the printing test form; Data acquisition module is taken on voltage, the current data acquisition tasks in the primary measured winding power on/off process; Data processing module is responsible for voltage, the current signal of being gathered carried out data processing, and realization data filtering, winding parameter mean value calculation, exciting characteristic curve direct current represent to exchange the conversion of expression; Parameter calculating module is finished tested winding excitation property parameter (remanent magnetism coefficient, winding internal resistance, linear inductance) and is calculated.
Claims (5)
1, a kind of excitation characteristic test system for current transformer, comprise: power-supply system, measurement major loop, data acquisition system (DAS), control subsystem, central processing unit system and peripheral common apparatus, it is characterized in that, power-supply system is made up of full-bridge rectification module, filter capacitor and startup holding circuit, the full-bridge rectification module connects the startup holding circuit, starts holding circuit and connects filter capacitor; Measure major loop by damping resistance R
D, parallel resistance Rp, shunt capacitance Cp, tested winding form, parallel resistance Rp, shunt capacitance Cp and tested winding parallel connection, a damping resistance R on this basis again contacts
DData acquisition system (DAS) is by current sensor, voltage sensor, isolation module, temperature sensor, the analog channel of temperature transmitter and data collecting card is formed, the input end of current sensor and the tested winding polyphone of measuring in the major loop, the input end of voltage sensor is in parallel with tested winding, the lead-out terminal of current sensor and voltage sensor is connected with the input terminal of two isolation modules respectively, the lead-out terminal of two isolation modules then connects two analog input channels of data collecting card respectively, temperature sensor connects the resistance input terminal of temperature transmitter, the measuring resistance of connecting in the electric power loop of temperature transmitter, and the signal of this standard resistor at two terminals is sent to another analog quantity channel of data collecting card; Control subsystem is made up of data acquisition card digital amount output channel, three solid-state relays, three electromagnetic relays, three contactors, data acquisition card digital amount output channel comprises three tunnel outputs, amplify through the isolation of three solid-state relays and three electromagnetic relays respectively and send into three contactless contactors, control survey major loop; Central processing unit system connects data acquisition system (DAS) and control subsystem by data collecting card, is connected with peripheral common apparatus simultaneously.
2, excitation characteristic test system for current transformer as claimed in claim 1, it is characterized in that, in control subsystem, data acquisition card digital amount output channel comprises test control DO0, winding is oppositely controlled DO1, main power switch control DO2, three solid-state relays are primary power control SSR1, winding is oppositely controlled SSR2, test control SSR3, three electromagnetic relays are primary power control KM1, winding is oppositely controlled KM2, test control KM3, three contactors are main power switch KS1, winding reverser KS2, Test Switchboard KS3, data acquisition card digital amount output DO2, DO1, DO0 connects solid-state relay SSR1 respectively, SSR2, the input terminal of SSR3, and solid-state relay SSR1, SSR2, the lead-out terminal of SSR3 respectively with electromagnetic relay KM1, KM2, the coil of KM3 is cascaded and is connected in the power supply of 24VDC, electromagnetic relay KM1, KM2, the normally opened contact of KM3 respectively with contactor KS1, KS2, the coil of KS3 is cascaded and is connected in 220VAC, the 50Hz power supply.
3, as claim 1 or 2 described excitation characteristic test system for current transformer, it is characterized in that, the main power switch KS1 of control subsystem connects 220VAC, the alternating current of 50Hz and power-supply system, the Test Switchboard KS3 of control subsystem connects power-supply system and measures major loop, and the reverse gauge tap KS2 of the winding of control subsystem connects measurement major loop and tested winding.
4, excitation characteristic test system for current transformer as claimed in claim 1, it is characterized in that, central processing unit system is made of the industrial control computer that has the isa bus expansion slot, moved Windows on it, by the control of the multi-functional ISA data collecting card realization on the control isa bus expansion slot to data acquisition system and control subsystem.
5, excitation characteristic test system for current transformer as claimed in claim 1 is characterized in that, peripheral common apparatus is made up of a printer, LCD, operation keyboard and a mouse.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101769968B (en) * | 2009-12-24 | 2013-05-01 | 宁波电业局 | Mutual inductor no-load voltage ratio tester |
| CN103149517A (en) * | 2013-03-20 | 2013-06-12 | 长沙唯高电气有限公司 | Insulation, aging and nondestructive detection device and method for oil-immersion equipment based on virtual instrument |
| CN103176147A (en) * | 2013-03-13 | 2013-06-26 | 江苏省电力公司电力科学研究院 | Current transformer remanence measurement system and method |
| CN103728510A (en) * | 2013-12-18 | 2014-04-16 | 国电南瑞科技股份有限公司 | Site testing system and method for excitation device |
| CN105137347A (en) * | 2014-05-29 | 2015-12-09 | 国网山西省电力公司电力科学研究院 | Instrument calibration system with specified power output function and instrument calibration method |
| CN110488215A (en) * | 2019-09-17 | 2019-11-22 | 深圳市晶扬电子有限公司 | Current transformer tests circuit, method and device |
| CN112924920A (en) * | 2021-02-02 | 2021-06-08 | 中国南方电网有限责任公司超高压输电公司柳州局 | Portable measuring device and parameter measuring method for high-voltage electromagnetic voltage transformer |
| CN116609578A (en) * | 2023-07-06 | 2023-08-18 | 深圳柯力三电科技有限公司 | High-precision digital current sensor and testing method thereof |
-
2004
- 2004-10-28 CN CN 200410067566 patent/CN1603852A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101769968B (en) * | 2009-12-24 | 2013-05-01 | 宁波电业局 | Mutual inductor no-load voltage ratio tester |
| CN103176147A (en) * | 2013-03-13 | 2013-06-26 | 江苏省电力公司电力科学研究院 | Current transformer remanence measurement system and method |
| CN103176147B (en) * | 2013-03-13 | 2014-11-19 | 江苏省电力公司电力科学研究院 | Current transformer remanence measurement system and method |
| CN103149517A (en) * | 2013-03-20 | 2013-06-12 | 长沙唯高电气有限公司 | Insulation, aging and nondestructive detection device and method for oil-immersion equipment based on virtual instrument |
| CN103728510A (en) * | 2013-12-18 | 2014-04-16 | 国电南瑞科技股份有限公司 | Site testing system and method for excitation device |
| CN105137347A (en) * | 2014-05-29 | 2015-12-09 | 国网山西省电力公司电力科学研究院 | Instrument calibration system with specified power output function and instrument calibration method |
| CN110488215A (en) * | 2019-09-17 | 2019-11-22 | 深圳市晶扬电子有限公司 | Current transformer tests circuit, method and device |
| CN112924920A (en) * | 2021-02-02 | 2021-06-08 | 中国南方电网有限责任公司超高压输电公司柳州局 | Portable measuring device and parameter measuring method for high-voltage electromagnetic voltage transformer |
| CN116609578A (en) * | 2023-07-06 | 2023-08-18 | 深圳柯力三电科技有限公司 | High-precision digital current sensor and testing method thereof |
| CN116609578B (en) * | 2023-07-06 | 2024-04-16 | 深圳柯力三电科技有限公司 | High-precision digital current sensor and testing method thereof |
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