CN103149546B - The field integrated tester of a kind of portable electric energy measuring terminal - Google Patents

The field integrated tester of a kind of portable electric energy measuring terminal Download PDF

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Publication number
CN103149546B
CN103149546B CN201210503041.3A CN201210503041A CN103149546B CN 103149546 B CN103149546 B CN 103149546B CN 201210503041 A CN201210503041 A CN 201210503041A CN 103149546 B CN103149546 B CN 103149546B
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module
arithmetic processor
electric energy
input
portable electric
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CN103149546A (en
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张庆辉
金广锋
张强
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Henan University of Technology
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Henan University of Technology
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Abstract

The present invention relates to the field integrated detector of a kind of portable electric energy measuring terminal, comprise arithmetic processor (1), arithmetic processor (2), voltage sample module, current sample module, gain merit and idle Puled input module, AD converter, display, keyboard, sampling handover module and gain amplification module, this detector also comprises switching value output module, control to detect load module, carrier communication module, gain merit and idle pulse output module, control to detect load module and be used for electrical energy parameter calculation and control, arithmetic processor (1) by an output switching model calling to pulse output module and switching value output module, pulse output module is used for more high precision instrument gauge check, switching value output module is used for control signal and exports and the input of tested facility switching amount, carrier communication module is used for by infrared communication interface, complete detection that is infrared and carrier communication.Solve the problem that existing electric power meter on-site calibrator verifying function is single.

Description

The field integrated tester of a kind of portable electric energy measuring terminal
Technical field
The present invention relates to the field integrated tester of a kind of portable electric energy measuring terminal.
Background technology
Along with developing rapidly of national economy, the raising day by day of living standards of the people, and the fast development of regional economy, the demand of Electricity customers is not that " have electricity according to bright " is just satisfiable already, but needs " Electrical Safety, power supply is reliable, electric energy is of fine quality, working is efficient, have reasonable fee, provide good service ".The service level in current electrical power services market, also there is a big difference with economic development and customer demand, and many demands of client can't meet or meet well.Customer demand determines market development direction, and therefore the current potential demand to high-quality, the service of efficient, thoughtful power technology is very large, also strongly.
Current electric power meter on-site calibrator is generally by voltage sample module, current sample module, analog switch, A/D converter, processor, Puled input module, keyboard and display composition, during field-checking, by the sampling module of the voltage and current signal of school electric energy meter access instrument, the conversion of signal is carried out by processor control simulation switch, and by AD converter, simulating signal is converted to digital signal, real-time calculating electric parameter, calibration voltage, the size of electric current, and acquisition pulse signal, detect the size of electric energy, finally realize the verification of electric power meter.But existing this tester is exactly generally the size verifying electric current, voltage, power, electric energy, and verifying function is single, and only carried out the switching of voltage, current signal by an analog switch, switch speed is slow, power consumption is higher.
Summary of the invention
The object of this invention is to provide the field integrated tester of a kind of portable electric energy measuring terminal, in order to solve the single problem of existing electric power meter on-site calibrator verifying function.
For achieving the above object, the solution of the present invention is: the field integrated tester of a kind of portable electric energy measuring terminal, comprises arithmetic processor (1), arithmetic processor (2), voltage sample module, current sample module, gain merit and idle Puled input module, AD converter, display, keyboard, sampling handover module and gain amplification module, described sampling handover module is analog switch, gain amplification module described in described voltage sample model calling, this gain amplification module is by described AD converter concatenation operation processor (1), analog switch described in described current sample model calling, this analog switch connects described gain amplification module, described gain amplification module is connected to arithmetic processor (1) by described AD converter, the input port of described meritorious and idle Puled input model calling arithmetic processor (1), this tester also comprises switching value output module, control to detect load module, carrier communication module, gain merit and idle pulse output module, described control detects load module input concatenation operation processor (1), for electrical energy parameter calculation and control, described arithmetic processor (1) by an output switching model calling to pulse output module and switching value output module, described pulse output module is used for more high precision instrument gauge check, described switching value output module is used for control signal and exports and the input of tested facility switching amount, described carrier communication module inputs with described arithmetic processor (1) and is connected, for by infrared communication interface, complete detection that is infrared and carrier communication.
This tester also comprises contact control module, arithmetic processor (2) described in this model calling;
Described voltage sample module comprises three-phase voltage input signal end, overvoltage protective module and divider filter module, and three-phase input voltage, after described overvoltage protective module, is sampled by described divider filter module.
Described current sample module comprises current transformer and split core type current transformer, adopts metal film sampling resistor to sample respectively at described current transformer and split core type current transformer secondary side.
Described gain amplification module is gear switch module, and described gear switch module is the programmable gain amplifier with multiple gain, amplifies for selecting different gains as required.
Described Puled input and output module adopt 6N173 High-Speed Coupled Device.
Described display adopts the liquid crystal display of band touch function.
Described arithmetic processor (1) and arithmetic processor (2) employing model are the high speed ARM arithmetic processor of STM32F103VET6.
Described programmable gain amplifier adopts AD526JNZ.
The beneficial effect that the present invention reaches: the current signal of (1) current sample module of the present invention is first switched by analog switch, and then be input to two-stage programmable gain amplifier and amplify, have employed the elementary mode adding secondary two-stage gain amplifier and analog switch switching, the faster power consumption of switch speed is lower, and select the gain amplifier with different gains, voltage and current signal amplifies sampling by different gains, different signal inputs can be obtained, make small voltage and small area analysis also highly stable;
(2) the present invention not only has keyboard control module, also be provided with contact control module, display has the function of touch, when carrying out the calculating of electrical parameter, keyboard can be adopted and touch two kinds of modes and input the parameter needing to measure, when one of them breaks down, can make to carry out work in another way, improve the reliability of work;
(3) on-site calibrator of the present invention comprises the output of current sample, voltage sample, Puled input output, control inputs, switching value, voltage, electric current and electric energy detection can not only be carried out, Puled input detection can also be carried out, control to detect and remote signalling detection, multi-functional detection can be realized.
Accompanying drawing explanation
Fig. 1 is the field integrated tester theory diagram of portable electric energy measuring terminal of the present invention;
Fig. 2 is the principle schematic of voltage check part of the present invention;
Fig. 3 is the principle schematic of electric current check part of the present invention;
Fig. 4 is the principle schematic that pulse of the present invention exports;
Fig. 5 is the principle schematic of Puled input of the present invention;
Fig. 6 is transducer check schematic diagram of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the present invention will be further described in detail.
As shown in Figure 1, on-site calibrator of the present invention comprises voltage sample module, current sample module, sampling module switching, gear switch module, ultra high speed A/D conversion module, RS232 communication module, RS485 communication module, meritorious, idle Puled input and output module, control and detects load module, switching value output module, carrier communication module, output switching module, liquid crystal display and contact control module and keyboard control module composition.
Voltage signal is by voltage sample module samples, and the signal obtained of sampling selects suitable gain to carry out gain amplification through gear switch switch, then through AD converter, then is admitted to operation processing unit 1; Current sample module comprises mutual inductor sample and split-core type meter sampling, two-way current signal after sampling is after the selection of over-sampling handover module, sending into gear switch switch selects suitable gain to carry out gain amplification, then through AD converter, then is admitted to operation processing unit 1; Meritorious and the idle pulse input signal that Puled input module produces is admitted to arithmetic processor 1 through amplitude limit, shaping pulse and isolation; Control detection, On-off signal and output switching to control by optocoupler TLP521, input quantity is through TLP521 to arithmetic processor 1, and output quantity is sent through TLP521, and input and output switch by four-way analog switch; Arithmetic processor 1 is according to the various signals received, carry out computing, judgement, and result is sent into arithmetic processor 2, arithmetic processor 2 according to keyboard or touch control input needs measure parameter and constant of electric energy meter, calculate the parameter needing verification, and result of calculation is shown by display.
Arithmetic processor 1 is also connected with RS232 communication module, RS485 communication module and carrier communication module, by 232 general interfaces, conveniently receive computer, may be used for several functions such as checking meter, RS485 communication module is by internal state machine and additional reception comparer, can judge to be other nodes on device itself or network when front wheel driving bus, and by with the coordinating of outside pull-up pull down resistor, the automatic reverse that data are transmitted can be realized.
With the equipment of carrier communication module, carrier communication Function detection is carried out to concentrator, collector, can by infrared communication interface, complete detection that is infrared and carrier communication: by infrared interface to detected equipment generation test command, if detected equipment receives orders, then return test data by carrier interface to tester, after tester checking, provide communication check result, complete detection that is infrared and carrier communication.The carrier module of different center frequency can be configured simultaneously, the carrier communication of various conventional acquisition terminal is detected.
To electric energy meter, concentrator and the electric energy metrical function check specially becoming acquisition terminal, can the voltage input end of tester be received on detected equipment, by current terminal, existing school instrument is sealed in the current input terminal of detected equipment, and connect the pulse output end of serial line interface or detected equipment, carry out real-time detection and treatment by electric current, voltage vector, realize by the test of calibration equipment electric energy metrical unit; By serial ports RS232 or RS485, contrast verification is carried out to the transmission of the data of these equipment, or measured by the pulse output that pulse detection port reads detected equipment, complete by the detection of calibration equipment electric energy metrical function.
To concentrator, the controlling functions detection specially becoming acquisition terminal, the detected control output of equipment of connection and the control of tester detect input end, when detected equipment sends corresponding control signal, the control output function of control inputs detecting unit to these equipment of tester detects, the signal pulse width and the waveform that detect its control output detect, and complete and detect and test the various control modules of equipment.
As Fig. 2; voltage acquisition module comprises three-phase voltage input signal end, overvoltage crowbar and pressure filter circuit; the three-phase voltage signal of input is after overvoltage crowbar; enter pressure filter circuit, adopt the metalfilmresistor potential-divider network of high, the Heat stability is good of precision to voltage sample, sample resistance selects 120 Ω; then divider resistance should select 4 50k Ω; the precision of resistance is 0.1%, and temperature coefficient is 5ppm, its maximum detection amount 576V peak value phase voltage.Voltage signal after sampling, through accurate program controlled programmable amplifier (PGA), exports ∑-Δ analog to digital converter (ADC) to, is finally admitted to arithmetic processor and carries out process computing.The computing formula of voltage data is as follows:
As Fig. 3, current acquisition module comprises current transformer and split core type current transformer, and current transformer selected range is the Miniature precision Current Transmit-X-1 of 0 ~ 20A, and its secondary rated current effective value is 10mA, sampling resistor R=18 Ω, accuracy class is 0.01 grade; The model that split core type current transformer adopts is KLC-8C type, the maximum 10A of primary current, and secondary surveys electric current 10mA, precision 0.1 grade, pull-up resistor 2 ohm.Mutual inductor secondary side uses metalfilmresistor sampling, and the mutual inductor output signal after sampling and split-core type meter output signal use low internal resistance analog switch MAX4679E to switch, and after PGA amplifies, export ADC to, then enter arithmetic processor and carry out process computing.The computing formula of current data is as follows:
As shown in Figure 4 and Figure 5, meritorious, idle Puled input and output circuit adopt High-Speed Coupled Device 6N137, and Puled input and output quantity are all provided by ARM arithmetic processor, and isolate through 6N137.High and low frequency input pulse is switched by the analog switch 74HC4052 of four-way, and high-frequency impulse produces low-frequency pulse through 10000 frequency divisions.Tester input pulse uses high speed photo coupling to carry out electrical isolation; conservation treatment device; and improve equipment antijamming capability; input pulse error calculation adopts timer counter pattern; within the regular hour; statistics high-frequency impulse and input pulse number, and calculate electrical energy pulse error according to the meter constant that user is arranged, more more accurate and efficient than the use fixed pulse number of turns.Detected remote measurement to equipment, remote signaling function by Puled input, by specific pulse pattern and width judge the various state of equipment under test and partial function whether normal.
As Fig. 6, on mutual inductor detects, equipment provides mutual inductor a test signal, and measures its output signal at secondary side simultaneously, calculates the precision and stability of mutual inductor ratio.Can according to measurement data size automatic switching range in test process; Automatic storage: 50 groups of (fully loaded and underloading) measurement data can be stored; Robotization is whole: can automatically carry out error informationization according to the class of accuracy of tested mutual inductor whole, and judge whether overproof; S level is directly measured; Directly can measure S level mutual inductor, measurement range is wide; According to the measurement point of regulatory requirements, by different accuracy requirement, can automatically carry out fully loaded and underloading measurement.
Measurement range:
In-phase component (%): 0.0001 ~ 19.99 resolution: 0.001
Quadrature component (dividing): 0.001 ~ 500 resolution: 0.001
Impedance (W): 0.0001 ~ 6.99 resolution: 0.001
Admittance (ms): 0.0001 ~ 6.99 resolution: 0.001
Working range:
Electric current: (1% ~ 150%) In(In=5A)
(5%~150%)In(In=1A)
Voltage: (5% ~ 150%) Un(Un=100V, 150V, 100V/)
(5%~190%)Un(Un=100V/3)
The field integrated tester of the present invention comprises electric energy acquisition mainboard, control base plate and guidance panel, this electric energy acquisition mainboard comprises current collection circuit, voltage collection circuit, Puled input output circuit, control testing circuit, 485 telecommunication circuits, 232 telecommunication circuits and battery electric quantity Acquisition Circuit, for gathering three-phase voltage, electric current, phase angle, calculate active power, reactive power and power factor, and measuring parameter is sent to control base plate, can check and specially become acquisition terminal, negative control terminal, mutual inductor, the basic function of concentrator and collector and communication function whether normal,
Guidance panel provides various patch jack, splicing ear, supply socket and gauge tap, supply socket is used for providing power supply to system, gauge tap is used for control system state, patch jack is for introducing three-phase voltage and three-phase current, splicing ear is used for pulse detection, remote signalling detects, connect forcipated mutual-inductor and with specially become acquisition terminal and communicate, possess mutual inductor output signal and secondary input end signal measuring ability, guidance panel is also for connecting low voltage electric power carrier communication module and the infrared communication module of concentrator or collector, be used for verifying the communication function of concentrator,
Control base plate to be connected with guidance panel, this control base plate comprises carrier wave input/output port, keyboard, touch screen control circuit, signal output interface, usb communication circuit and power circuit, there is the function monitoring specially becoming acquisition terminal, concentrator, collector distribution transformer terminals and negative control terminal, the AC sampling unit of these equipment, data transmission unit and output control unit can be detected.

Claims (9)

1. the field integrated tester of portable electric energy measuring terminal, comprise the first arithmetic processor, second arithmetic processor, voltage sample module, current sample module, gain merit and idle Puled input module, AD converter, display, keyboard, sampling handover module and gain amplification module, described sampling handover module is analog switch, gain amplification module described in described voltage sample model calling, this gain amplification module connects the first arithmetic processor by described AD converter, analog switch described in described current sample model calling, this analog switch connects described gain amplification module, described gain amplification module is connected to the first arithmetic processor by described AD converter, the input port of described meritorious and idle Puled input model calling first arithmetic processor, it is characterized in that,
This tester also comprises switching value output module, controls to detect load module, carrier communication module, meritorious and idle pulse output module, and described control detects load module input connection first arithmetic processor, for electrical energy parameter calculation and control, described first arithmetic processor passes through an output switching model calling to meritorious and idle pulse output module and switching value output module, described meritorious and idle pulse output module is used for more high precision instrument gauge check, described switching value output module is used for control signal and exports and the input of tested facility switching amount, described carrier communication module is connected with described first arithmetic processor input, for by infrared communication interface, complete detection that is infrared and carrier communication: by infrared communication interface to detected equipment generation test command, if detected equipment receives orders, then return test data by carrier interface to tester, communication check result is provided after tester checking.
2. the field integrated tester of portable electric energy measuring terminal according to claim 1, it is characterized in that, this tester also comprises contact control module, the second arithmetic processor described in this model calling.
3. the field integrated tester of portable electric energy measuring terminal according to claim 1; it is characterized in that; described voltage sample module comprises three-phase voltage input signal end, overvoltage protective module and divider filter module; three-phase input voltage, after described overvoltage protective module, is sampled by described divider filter module.
4. the field integrated tester of portable electric energy measuring terminal according to claim 1, it is characterized in that, described current sample module comprises current transformer and split core type current transformer, adopts metal film sampling resistor to sample respectively at described current transformer and split core type current transformer secondary side.
5. the field integrated tester of portable electric energy measuring terminal according to claim 1, it is characterized in that, described gain amplification module is gear switch module, described gear switch module is the programmable gain amplifier with multiple gain, amplifies for selecting different gains as required.
6. the field integrated tester of portable electric energy measuring terminal according to claim 1, is characterized in that, described meritorious and idle Puled input and output module adopt 6N137 High-Speed Coupled Device.
7. the field integrated tester of portable electric energy measuring terminal according to claim 1, is characterized in that, described display adopts the liquid crystal display of band touch function.
8. the field integrated tester of portable electric energy measuring terminal according to claim 1, is characterized in that, described first arithmetic processor and the second arithmetic processor employing model are the high speed ARM arithmetic processor of STM32F103VET6.
9. the field integrated tester of portable electric energy measuring terminal according to claim 5, is characterized in that, described programmable gain amplifier adopts AD526JNZ.
CN201210503041.3A 2012-11-30 2012-11-30 The field integrated tester of a kind of portable electric energy measuring terminal Active CN103149546B (en)

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CN106093841A (en) * 2016-08-25 2016-11-09 海盐星创电子有限公司 A kind of hand-held electric energy meter on-site calibrator
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CN108267705A (en) * 2016-12-30 2018-07-10 武汉市欧睿科技有限公司 Capacitance type potential transformer calibration equipment
CN108109363A (en) * 2018-01-31 2018-06-01 深圳市锦熹科技有限公司 Check instrument and application method in a kind of intelligent electric meter scene based on infrared communication

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2261029Y (en) * 1996-10-09 1997-08-27 毛晋 Comprehensive calibrator for electric measuring device
CN2427816Y (en) * 2000-06-19 2001-04-25 瞿清昌 Instrument for measuring and calibrating electricity meter testing device
CN1620613A (en) * 2002-01-09 2005-05-25 三菱电机株式会社 Electronic watt-hour meter, error adjusting method, and power calculating circuit
CN2709998Y (en) * 2004-01-19 2005-07-13 河南思达高科技股份有限公司 Portable on-site tester for electric energy meter
CN201188118Y (en) * 2008-03-19 2009-01-28 广东东方电讯科技有限公司 Whole electronic type intelligent electric meter
CN202903993U (en) * 2012-10-26 2013-04-24 郑州瑞能电气有限公司 Portable on-site calibrator for electric energy collection terminal

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61126485A (en) * 1984-11-22 1986-06-13 Toshiba Corp Error measuring instrument
ES2040012T3 (en) * 1989-12-14 1993-10-01 Landis & Gyr Business Support Ag PROVISION FOR THE DETERMINATION OF VALUES OF ELECTRICAL MAGNITUDES, WHICH CAN BE DEDUCTED FROM MEASURING VALUES OF AT LEAST TWO ELECTRICAL MAGNITUDES OF ENTRY OF THE DISPOSITION.
JP3330519B2 (en) * 1997-08-11 2002-09-30 三菱電機株式会社 Electronic watt-hour meter and its error adjustment method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2261029Y (en) * 1996-10-09 1997-08-27 毛晋 Comprehensive calibrator for electric measuring device
CN2427816Y (en) * 2000-06-19 2001-04-25 瞿清昌 Instrument for measuring and calibrating electricity meter testing device
CN1620613A (en) * 2002-01-09 2005-05-25 三菱电机株式会社 Electronic watt-hour meter, error adjusting method, and power calculating circuit
CN2709998Y (en) * 2004-01-19 2005-07-13 河南思达高科技股份有限公司 Portable on-site tester for electric energy meter
CN201188118Y (en) * 2008-03-19 2009-01-28 广东东方电讯科技有限公司 Whole electronic type intelligent electric meter
CN202903993U (en) * 2012-10-26 2013-04-24 郑州瑞能电气有限公司 Portable on-site calibrator for electric energy collection terminal

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