CN1066508A - Intelligence testing device of watthour meter - Google Patents

Intelligence testing device of watthour meter Download PDF

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Publication number
CN1066508A
CN1066508A CN 92103325 CN92103325A CN1066508A CN 1066508 A CN1066508 A CN 1066508A CN 92103325 CN92103325 CN 92103325 CN 92103325 A CN92103325 A CN 92103325A CN 1066508 A CN1066508 A CN 1066508A
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China
Prior art keywords
microcomputer
electric energy
digital
forming
energy meter
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CN 92103325
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Chinese (zh)
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CN1028452C (en
Inventor
卢运培
熊敏南
李东江
靳绍平
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JIANGXI POWER TEST INST
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JIANGXI POWER TEST INST
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Publication of CN1028452C publication Critical patent/CN1028452C/en
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Abstract

A kind of with the intelligence testing device of watthour meter of microcomputer as core component, be provided with full sized pules oscillating component by the monolithic unit, the frequency modulation parts of forming by phaselocked loop, programmable counter, the am component of forming by digital/analog signal converter and high steady reference signal source, by the phase modulation assembly that programmable counter, data memory are formed, be provided with also that three tunnel pulses always add counter block, one to three tested electric energy meter circle control parts and by the amount limit automatic switchover parts of programmable parallel interface chip, driver and execution unit.The microcomputer that the present invention adopts had both produced and had contained the harmonic wave derived digital signal, controlled auto-adjustment again, had reduced peripheral hardware significantly.

Description

Intelligence testing device of watthour meter
The invention belongs to measured value and automatically compare and measure the device of electric variable, further belong to a kind of intelligence testing device of watthour meter that adopts microcomputer as core component with reference value.
The medium-sized power administration that general year delivery is 1,500,000,000 kilowatt-hours, need the calibrating electric energy meter every year nearly 10,000 times, and the electric energy metrical direct relation power department and users' economic interests, therefore, the electric energy meter calibrating apparatus of development high precision, high-intelligentization is the heat subject of Chinese scholars always.The calibrating of electric energy meter adopts relative method to carry out mostly.Tested electric energy meter has single-phase, three-phase (triple-phase line, three-phase and four-line), meritorious, idle, direct access type (low-pressure meter) and through mutual inductor access type (high pressure gauge) or the like.To preset tested table circle according to tested table and mark rate constant (change/kilowatt-hour), calculate and decide umber of pulse that standard scale should send out and the standard scale error of the tested electric energy meter of (1) calculating just by formula:
r= (mo-m)/(m) ×100+rb……(1)
In the formula (1): m: the real umber of pulse of receiving;
Mo: calculate and decide umber of pulse;
Rb: calibrating installation fixed system error.
In the formula (2): mo=nos ... (2)
S: standard electric energy meter is goed around, the umber of pulse that the pulse display should show;
No: calculate and decide revolution no=(Co N)/(C kl ky ki kv kj) ... (3)
C: examine and determine table constant (commentaries on classics/kilowatt-hour);
Co: the standard scale constant (change/kilowatt-hour);
N: the tested table number of turns;
Kx=KL.Ky.Ki.Kv.Kj
Kx:CT, PT no-load voltage ratio and connection factor.
From the course of work of above summary as can be seen, by the control of calibrating table fixing turn, standard scale (generally using three single-phase composition three-phases) wants three tunnel pulses always to add counting, want the error of calculation, want revision of the convention result, want the systematic error of feeder apparatus, it is (meritorious that (being deviation) will carry out function selecting, idle, single-phase etc.) want the switch current range, change electric current, voltage, phase angle, file, print, also will judge the reliability of verification result, adopt microcomputer can satisfy above-mentioned requirements as the high-intelligentization electric energy meter calibrating apparatus of core, but the calibrating installation that has come out still is only limited to the data processing of calculating gauging error, also have in addition and to make slave and micro-mainframe computer serial communication with single-chip microcomputer and produce digital signal, but contained harmonic wave only there is in odd harmonic and the verification process electric current limit the quantity of and can not automatically switch.
Purpose of the present invention is exactly at the above-mentioned not enough more good intelligence testing device of watthour meter of a kind of performance that proposes.
The object of the present invention is achieved like this:
Composition of the present invention is prior art roughly the same, and it is by three-phase FMAM phase modulation derived digital signal, microcomputer, the digital/analog signal converter, power amplifier, the voltage function selector switch, the magnitude of current is limit switch and is made up of the standard electric energy meter of pulse signal output.And it is characterized in that: be provided with the full sized pules oscillating component of forming by single-chip microcomputer, by the CPU (central processing unit) CPU and the timer conter CTC generation oscillator signal of single-chip microcomputer inside;
Be provided with the fm components of forming by phaselocked loop, programmable counter, phaselocked loop with oscillating impulse phase locking frequency multiplying programmable counter according to specified frequency preset frequency division numerical value;
Be provided with the am component of forming by digital/analog signal converter D/A and high steady reference signal source Vrf, change D by microcomputer according to presetting amplitude, because of the Vo=D.Vrf of D/A output;
Be provided with the phase modulation assembly of forming by programmable counter, data memory, change the digital quantity of releasing the data memory respective point as the count frequency of address according to being good for into angle values by microcomputer;
Also be provided with one three tunnel pulse and always add counter block, according to being good for into harmonic number, the stack first-harmonic is exported through digital/analog signal converter D/A by microcomputer; Also be provided with one to three tested electric energy meter circle control parts, it leaves interruptable controller that the user uses and shaping, pulse narrowing circuit for by microcomputer, tested electric energy meter photoimpact is given interruptable controller through shaping, after narrowing down, and microcomputer response interrupt mode is carried out the circle control;
Its magnitude of current limit switch is custom-designed amount limit automatic switchover parts, and it is by the programmable parallel interface chip, and driver and execution unit are formed, by the automatic gating parallel interface of microcomputer internal memory software chip gear through driver control.
The microcomputer that the present invention adopts had both produced and had contained the harmonic wave derived digital signal, control auto-adjustment again, reduced peripheral hardware significantly, made full use of the internal resource of microcomputer, signal self frequency modulation, amplitude modulation, phase modulation, simple and reliable, owing to used system's machine,, quantification harmonic function value discrete, assembly language control output with higher level lanquage, the present invention can inject or inject simultaneously the 2-20 subharmonic respectively by software design, and can separately or be superimposed on its first-harmonic output.The amplitude of multiple harmonic is the 0-40% of fundamental voltage amplitude, the present invention by microcomputer to three single-phase standard scale electric energy.Realize that three tunnel pulses always add, count, counter capacity and speed are all unrestricted.To 100,000,000 every kilowatt-hour (10 8) the RM1 type standard electric energy meter of pulse and the K6 type standard electric energy meter of every kilowatt-hour of 1666 pulses, can both accurate counting, the present invention also realizes the control of the calibrated meter number of turns by microcomputer, needn't set the hardware circuit of circle in addition, also can expand easily, to examine and determine many electric energy meters simultaneously, improve work efficiency, this suits to the enterprise that produces electric energy meter.At last, the present invention can control the switching of more a plurality of magnitudes of current limits by the control automatically of microcomputer realization amount limit, makes standard electric energy meter under any circumstance all operate in the load range that 50-120% that electric current limits the quantity of guarantees calibration accuracy.Thereby it is few to make the present invention have hardware, the reliability height, and every technical indicator is better than national verification rules " JJG597-89 ", to every technical requirement of 0.03 calibrating installation.Adopt relative method, can be automatically or the reconnaissance calibrating is single, three-phase is meritorious, reactive energy-meter by the rules overall process, the fault self-diagnosable, it is very convenient that operation is guided by menu, dynamic process CRT shows, very directly perceived, the result presses the output of probation redport format print, deposits after the data processing, get dish, functions such as standard scale error correction are all set, can require according to verification worker free, be the calibrating electric energy meter ideal equipment.
The present invention has the following drawings:
Fig. 1 is that the present invention forms block scheme;
Fig. 2 is the composition block scheme of three-phase FMAM phase modulation derived digital signal of the present invention;
Fig. 3 is that pulse of the present invention always adds the counter block circuit diagram;
Fig. 4 is tested electric energy meter circle control component circuitry figure of the present invention;
Fig. 5 is amount limit automatic switchover component circuitry figure of the present invention;
Fig. 6 is a software block diagram of the present invention.
Below in conjunction with embodiment and contrast accompanying drawing the invention will be further described:
Embodiment:
Derived digital signal produces the 4.096HZ full sized pules by single-chip microcomputer 8748, passes to phaselocked loop, and phaselocked loop obtains required frequency through the programmable counter frequency multiplication.
Data selector is finished the selection that write data writes RAM and waveform generation output.
Data are write fashionable, program control I/O(A) the corresponding RAM sheet of gating, by 12 digit counters as the address, sense data from microcomputer IBM-PC, according to three-phase and four-line, the phase three-wire three method writes random memory ram with data.
When waveform took place, all RAM sheets of gating, 12 digit counter numerical value were as address ram enabling counting device, and behind the counting, the RAM data are through D/A converter, and synthetic waveform output again through amplification filtering, undistorted sinusoidal waveform takes place.
Program control I/O(B) play two kinds of effects, the one, transfer data to D/A converter and change wave-shape amplitude; The 2nd, control during the automatic Verification electric energy meter, programmable counter 2, full sized pules always adds counting usefulness when making the calibrating electric energy meter.
The frequency of single-chip microcomputer 8748 outputs is constant, programmable counter change value, and promptly the frequency multiplication value changes, and discrete the counting of one-period is constant, output frequency respective change when changing the frequency multiplication data realizes frequency modulation.
Embodiment is provided with independent control width of cloth circuit, as long as change the D/A converter input data that amplitude modulation is used with instruction, and can rapid amplitude modulation.
The phase place regulation and control realize by movable random ram memory cell data, when control phase, the input angle values, program is worth movable random ram memory cell data forward or backward mutually according to input, realize leading or hysteresis phase shift, promptly the every degree of 6 tunnel output random memory ram corresponding unit values differs 4096/360.
The function expression of the distorted wave of stack higher hamonic wave is:
F(t)=Ulsinwt+Unsin(nwt+ Φ) [+... ] (n>1) first-harmonic value and 2-20 multifrequency sinusoid value, the random memory ram, U1 and the Un that deposit microcomputer IBM-PC in import with number percent.Program with digital wave discrete quantized number percent on duty after, according to Un data are added and subtracted, the result writes random memory ram, the distorted wave after obtaining superposeing.
The microcomputer that embodiment adopts is the IBM-PC machine, also can adopt its compatible Great Wall 0520.
Power amplifier is produced by Jiangxi Electronic Instruments Plant; it is a kind of OCL power amplifier with operational amplifier; can under 1.2 times of specified outputs, work; be provided with the voltage short circuit; the current open protection; voltage is output as constant pressure source, and electric current is output as constant current source, and output capacity is designed to the 30-100 volt-ampere as required.
Standard electric energy meter is the built-in mutual inductor, 0.025 grade of RM-11 type standard electric energy meter that pulse output is arranged of auto-range.
The accurate electric energy meter pulse of three road signs always adds counter block and is made up of two programmable count/timers 8258, and 8253 have three independently 16 digit counters, and during the two-stage coupling, counter capacity can reach 2 31Individually be equivalent to 10 9, count rate 10 6/ second, pulse to any standard electric energy meter does not need frequency division can always add counting, A, B, C are that three tunnel umber of pulses are delivered to the CRT demonstration among Fig. 3, the CPU8088 control of IBM-PC, it is delivered to CRT to the umber of pulse of being received and shows, address decoder 74LS138 is controlled by CPU8088 also, so that remove to choose 8253(1 as required), 8253(2) or amount limit automatic switchover parts in parallel interface chip 8255, Ai presentation address line among Fig. 3, Di represents data line, RD, WR are control line, all are connected on three buses of microcomputer IBM-PC.
The 1-3 only circle control parts of tested electric energy meter is to utilize that programmable interrupt controller 8259 offers 6 external interrupt mouths that the user uses in the microcomputer IBM-PC machine, and the circle control signal of 3 tested electric energy meters is that the tested electric energy meter photoelectric sampler that whenever turns around forms electric impulse signal among Fig. 4.This signal is by the input of 2.6 pin of 555 circuit, after 555 circuit shapings to IO interface IO expansion slot three bus input end IRQ 2, IRQ 3, IRQ 4, enter programmable interrupt controller 8259 in the microcomputer IBM-PC machine again.Expand 8259, can increase the number of tested electric energy meter.The CPU8088 response external is interrupted, preset the number of turns and subtract 1, up to reducing to 0, promptly block programmable counter/timer 8353, and by software to 8253(1) and the umber of pulse of 8253(2) being counted handle, comprise phase adduction and Theoretical Calculation umber of pulse relatively, calculate this error, send demonstration, judge and qualifiedly deny or the like.
Amount limit automatic switchover parts are to add expansion a slice parallel interface chip 8255 on the counter block always, and its 6 pin connects and always adds counter block way address code translator 74LS138 and Y1.When CPU8088 makes the Y1 of 74LS138 be low level, promptly choose 8255,8255 data line Do-D7, address wire Ao, Al and control line RD, WR and reset line RESET also to be connected in the IO interface I/O groove, be subjected to the CPU8088 instruction control.8255 A mouth, B mouth, the output of C mouth promptly are used for controlling automatic switchover magnitude of current limit, magnitude of current existence 20A, 10A ... 0.1A totally 12 grades.Only draw among Fig. 5 by the circuit of PC1 high level output by driving stage control 20A.
The software of embodiment shows whole Hanzifies, and operation is guided by menu, and Fig. 6 has only listed master menu, and in fact per step test all has submenu and prompting operation key, and the dynamic process of test has demonstration, and is very directly perceived, easy.Software is made up of " CCDOS " dish and " calibration program " two floppy disks, and " CCDOS " is used to start microcomputer IBM-PC and enters the Chinese operating system calibration.Program is divided into 5 modules:
1, self-checking system: utilize microcomputer testing, calculate this device composition error, table body error, standard deviation and standard scale and compare mutually, the observation caliber deviation can find at any time whether device is unusual during the inspection table.This is a self-diagnostic function of the present invention.Program enters after the self-checking system display menu on screen: 1, phase place, 2, amplitude, 3, deviation, 4, return.Key in " 3 " again by display reminding speech on screen, promptly means of man-machine press the inquiry that shows: voltage? electric current? constant? sampling number? power factor? load? key in each parameter Deng successively, several M are preset in the display standard pulse then.The number of turns N that shows tested table (1,2,3 table) more successively 1, N 2, N 3, the actual umber of pulse M that receives 1, M 2, M 3And sampling error Y 1, Y 2, Y 3Whether the parameter (error mean, standard deviation, maximum residul difference) and the judgment data that promptly show each table after sampling finishes be reasonable,, illustrate not to be to cause, and may be that tested table variation is too big greater than 3 times of deviations as (Yi-Y) by accidental the interference, or device has fault, should ascertain the reason, and handles respectively.
2, output is provided with: when installing as calibrating indicating instrument or other tests, and electric current, the output of voltage has more detailed " man-machine conversation ".Amplitude, phase angle, elevation rate etc. all can preset by keyboard, and automatic lifting has quick-action (10%) and slow-action (1%), also have the fine tuning knob in addition, regulate fineness and can reach 0.01%.
3, meter correcting system: arrange software according to induction type electric energy meter vertification regulation " JJF307-88 " and electronic electric energy meter vertification regulation " JJF586-89 ".The table calibrating load of dissimilar and different brackets is all different with power rate, and menu has been drawn the verification step of the table of used type, the user order " dish " get final product.By rules overall process automatic Verification, still Selected Inspection is one or several, as long as " notice " microcomputer, program has the arrangement of strictness.The dynamic process of calibrating, the number of turns, the real umber of pulse of receiving are all shown by CRT.
4, data processing: be provided with the error revision of the convention, the standard scale error correction, result's deposit and historical machine account are got functions such as dish.
5, print: the result can print probation redport front cover and result data by the rules requirement according to consumers' opinions.

Claims (1)

1, a kind of by three-phase FMAM phase modulation derived digital signal, microcomputer, digital/analog signal converter, power amplifier, the voltage function selector switch, magnitude of current limit switch and the intelligence testing device of watthour meter of being made up of the standard electric energy meter of pulse signal output is characterized in that:
1.1 be provided with the full sized pules oscillating component of forming by single-chip microcomputer, by the processing CPU of central authorities and the timer conter CTC generation oscillating impulse of single-chip microcomputer inside;
1.2 be provided with by with the phaselocked loop of oscillating impulse phase locking frequency multiplying and the fm components of forming according to the programmable counter of specified frequency preset frequency division numerical value;
1.3 be provided with the am component of forming by digital/analog signal converter D/A and high steady reference signal source Vrf, change according to presetting amplitude by microcomputer, the output Vo of digital/analog signal converter D/A just changes the direct proportion coefficient value of exporting Vo and reference signal source Vrf;
1.4 be provided with the phase modulation assembly of forming by programmable counter and data memory, according to keying in the count frequency of phase angle change, release the digital quantity of data memory respective point as the address by microcomputer;
1.5 be provided with one by microcomputer according to keying in harmonic number stack first-harmonic and always adding the meter parts through the pulse of digital/analog signal converter D/A output;
1.6 be provided with one to three tested electric energy meter circle control parts, its interrupt control and shaped pulse narrowing circuit of leaving user's use for by microcomputer is formed, tested electric energy meter photoimpact is given the interruption program controller after shaping narrows down, microcomputer response interrupt mode is carried out the circle control;
1.7 be provided with the amount restraint switching part of forming by programmable parallel interface chip, driver and execution unit, it by microcomputer by the gear of depositing the automatic gating parallel interface of software chip, through driver control.
CN 92103325 1992-05-11 1992-05-11 Intelligence testing device of watthour meter Expired - Fee Related CN1028452C (en)

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Application Number Priority Date Filing Date Title
CN 92103325 CN1028452C (en) 1992-05-11 1992-05-11 Intelligence testing device of watthour meter

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Application Number Priority Date Filing Date Title
CN 92103325 CN1028452C (en) 1992-05-11 1992-05-11 Intelligence testing device of watthour meter

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CN1028452C CN1028452C (en) 1995-05-17

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101464501B (en) * 2007-12-20 2011-12-14 上海联能仪表有限公司 Calibrating apparatus for electric energy quality test analyzer
CN102636769A (en) * 2012-04-18 2012-08-15 山东电力研究院 Error counter for electric energy meter and error counting method
CN104330765A (en) * 2014-11-12 2015-02-04 成都天兴电气有限公司 Satellite navigation system based electric-energy-meter field calibration device
CN105445693A (en) * 2016-01-25 2016-03-30 云南电网有限责任公司电力科学研究院 Digital electricity meter calibration method and device
CN105487032A (en) * 2016-01-04 2016-04-13 国网山东省电力公司青岛供电公司 Verification device
CN106054113A (en) * 2016-07-27 2016-10-26 国网山东省电力公司电力科学研究院 Metering stability testing system for electric energy meter and testing method thereof
CN106352911A (en) * 2016-08-31 2017-01-25 丹东通博测控工程技术有限公司 Verification system provided with single-interrupt CPU and realizing acquisition of multiple channels of low-frequency transmission signals and acquisition verification method
CN108020806A (en) * 2017-07-28 2018-05-11 国网江西省电力公司电力科学研究院 Harmonic generator for intelligent electric energy meter detection
CN109870649A (en) * 2019-04-03 2019-06-11 广东省计量科学研究院(华南国家计量测试中心) A kind of calibration system and method for alternating-current charging pile calibrating installation
CN110109045A (en) * 2019-06-21 2019-08-09 广东电网有限责任公司 Test power supply and equipment for three-phase electrical energy meter for three-phase electric energy meter calibrating
CN112230180A (en) * 2020-09-27 2021-01-15 青岛鼎信通讯股份有限公司 Signal source phase modulation method of electric energy meter calibrating device based on FPGA

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101464501B (en) * 2007-12-20 2011-12-14 上海联能仪表有限公司 Calibrating apparatus for electric energy quality test analyzer
CN102636769A (en) * 2012-04-18 2012-08-15 山东电力研究院 Error counter for electric energy meter and error counting method
CN102636769B (en) * 2012-04-18 2014-08-27 山东电力研究院 Error counter for electric energy meter and error counting method
CN104330765B (en) * 2014-11-12 2017-07-18 成都天兴电气有限公司 Electric energy meter field calibrating installation based on satellite navigation system
CN104330765A (en) * 2014-11-12 2015-02-04 成都天兴电气有限公司 Satellite navigation system based electric-energy-meter field calibration device
CN105487032A (en) * 2016-01-04 2016-04-13 国网山东省电力公司青岛供电公司 Verification device
CN105445693A (en) * 2016-01-25 2016-03-30 云南电网有限责任公司电力科学研究院 Digital electricity meter calibration method and device
CN106054113A (en) * 2016-07-27 2016-10-26 国网山东省电力公司电力科学研究院 Metering stability testing system for electric energy meter and testing method thereof
CN106054113B (en) * 2016-07-27 2018-09-11 国网山东省电力公司电力科学研究院 A kind of quantification stability for electric energy meter tests system and its test method
CN106352911A (en) * 2016-08-31 2017-01-25 丹东通博测控工程技术有限公司 Verification system provided with single-interrupt CPU and realizing acquisition of multiple channels of low-frequency transmission signals and acquisition verification method
CN106352911B (en) * 2016-08-31 2018-06-26 丹东通博测控工程技术有限公司 Realize that the single of multichannel low frequency pick-up signal acquisition interrupts CPU verification systems and calibrating acquisition method
CN108020806A (en) * 2017-07-28 2018-05-11 国网江西省电力公司电力科学研究院 Harmonic generator for intelligent electric energy meter detection
CN108020806B (en) * 2017-07-28 2019-11-26 国网江西省电力公司电力科学研究院 Harmonic generator for intelligent electric energy meter detection
CN109870649A (en) * 2019-04-03 2019-06-11 广东省计量科学研究院(华南国家计量测试中心) A kind of calibration system and method for alternating-current charging pile calibrating installation
CN110109045A (en) * 2019-06-21 2019-08-09 广东电网有限责任公司 Test power supply and equipment for three-phase electrical energy meter for three-phase electric energy meter calibrating
CN112230180A (en) * 2020-09-27 2021-01-15 青岛鼎信通讯股份有限公司 Signal source phase modulation method of electric energy meter calibrating device based on FPGA

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