CN207366731U - A kind of intelligent electric energy meter detection device - Google Patents
A kind of intelligent electric energy meter detection device Download PDFInfo
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- CN207366731U CN207366731U CN201721236239.4U CN201721236239U CN207366731U CN 207366731 U CN207366731 U CN 207366731U CN 201721236239 U CN201721236239 U CN 201721236239U CN 207366731 U CN207366731 U CN 207366731U
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Abstract
The utility model discloses a kind of intelligent electric energy meter detection device, including signal generator, DSP, count comparator, frequency dividing setting unit, isolated location, three-phase standard voltage source, three-phase normalized current source and standard calibration device；The output of signal generator is connected through communication interface B with three-phase standard voltage source and three-phase normalized current source；The voltage port of standard calibration device is in parallel with the corresponding voltage port of tested table；Connect with the corresponding current port of tested table the electric current port of standard calibration device；Three-phase standard voltage source output voltage test signal, output port are connected with standard calibration device corresponding voltage port；Three-phase normalized current source output current test signal, output port are connected with standard calibration device corresponding current port.The utility model is adapted to the intelligent electric energy meter test of exceptional operating conditions, for examining metering accuracy of the intelligent electric energy meter in frequency fluctuation and amplitude fluctuations.
Description
Technical field
The utility model category Electric Energy Metering Technology field, in particular to a kind of intelligent electric energy meter detection device.
Background technology
As the important component of intelligent grid, the metering accuracy of intelligent electric energy meter directly affects the clearing of the electricity charge.
Current national verification code JJG596, standard GB/T/T 17215.321, European standard EN50470, international recommendation R46 etc.
Requirement is proposed to the performance of electric energy meter.
Traditional detection method is frequently with virtual load method and method of standard table：During detection, calibration power source output voltage and electricity
Flow signal；The voltage end of standard scale and tested table is in parallel, current terminal series connection；By control the amplitude of voltage and current, phase and
Frequency analog is tested the different live operating condition of table.Frequency shift is tested as defined in standard, and the frequency of test signal exists
0.98fnom~1.02fnom(fnomFor reference frequency) in the range of change.During experiment, the frequency for first making test signal is fnom, obtain
The relative error magnitudes of tested table；Change the frequency of test signal again, frequency is 0.98f at this timenom~1.02fnomIn the range of certain
One fixed value, obtains the relative error magnitudes of tested table；By allowable error as defined in the relative error change value of tested table and standard
Limit is compared, to judge whether tested table meets the requirements.However, the frequency of electric energy meter field line signal is often in certain model
Enclose interior round-trip fluctuation and with periodically, test signal when frequency shift is tested obviously cannot reflect such a operating condition.This
Outside, the current signal of impact load circuit, its amplitude only change sinusoidal current often with there is the characteristics of rapid fluctuations in a wide range
The virtual value of test signal obviously cannot reflect this operating condition.Even, access what the signal of electric energy meter was fluctuated in frequency
Meanwhile its current amplitude is also in rapid fluctuations.At present, a kind of intelligent electric energy meter test method is lacked, for examining electric energy meter to exist
Metering accuracy under above-mentioned various exceptional operating conditions.
Utility model content
The purpose of this utility model is to overcome the deficiencies in the prior art, there is provided one kind is adapted to exceptional operating conditions
Intelligent electric energy meter detection device, for examining metering accuracy of the intelligent electric energy meter in frequency fluctuation and amplitude fluctuations.
In order to solve the above-mentioned technical problem, the utility model is realized using following technical scheme：
What a kind of intelligent electric energy meter detection device was realized, including：Signal generator, DSP, count comparator, frequency dividing are set
Unit, isolated location, three-phase standard voltage source, three-phase normalized current source and standard calibration device.Signal generator is connect by communication
Mouth A is connected with DSP output terminals；The output terminal of DSP is connected with the input terminal of count comparator, the output terminal of DSP while and three-phase
The input terminal of standard voltage source is connected with the input terminal in three-phase normalized current source；The output terminal of count comparator connects with isolated location
Connect, the output of isolated location is connected with the first AD conversion unit in standard calibration device and the second AD conversion unit at the same time；Frequency dividing
Setting unit output is connected with count comparator control terminal；The output of signal generator is through communication interface B and three-phase normal voltage
Source and the connection of three-phase normalized current source；The voltage port of standard calibration device is in parallel with the corresponding voltage port of tested table；Standard school
Connect with the corresponding current port of tested table the electric current port of quasi- device；Three-phase standard voltage source output voltage test signal, output
Port is connected with standard calibration device corresponding voltage port；Three-phase normalized current source output current test signal, output port and mark
Quasi- calibrator corresponding current port connection.
Further preferably, the standard calibration device includes：Voltage sampling unit, current sampling unit, the first modulate circuit,
Second modulate circuit, the first AD conversion unit, the second AD conversion unit and MCU；The output of three-phase standard voltage source is adopted with voltage
The input connection of sample unit, the input of the output of voltage sampling unit and the first modulate circuit connect, the output of the first modulate circuit with
The input connection of first AD conversion unit；The output of first AD conversion unit is connected with MCU；The output in three-phase normalized current source with
The input connection of current sampling unit, the output of current sampling unit are connected with the input of the second modulate circuit, the second modulate circuit
Output is connected with the input of the second AD conversion unit；The output of second AD conversion unit is connected with MCU.
Signal generator by from n × m data of waveform extracting by PORT COM B be transferred to three-phase standard voltage source and
Three-phase normalized current source simultaneously stores；Signal generator is by each phase voltage and the time interval of each phase current test signal waveform extracting
Ti/ m values are transferred to DSP, and DSP is according to time interval Ti/ m output control pulses, control three-phase standard voltage source and three-phase standard electric
Stream source carries out DA conversions to the data of storage, is amplified by filtering process and signal, exports required each phase voltage and each mutually electricity
Current test signal.
Frequency dividing setting unit sets divider ratio n according to the actual requirements, and count comparator is constantly to the pulse signal of DSP outputs
Counted, and compared with divider ratio n is set；When count value is n, count value is reset and exports an arteries and veins by count comparator
Signal is rushed, so circulation realizes that the n of the pulse signal to DSP outputs is divided；Count comparator passes through isolated location output frequency division
Pulse signal afterwards, controls the first AD conversion unit in standard calibration device and the second AD conversion unit to be AD converted so that
Standard calibration device can realize the fully synchronized sampling to each phase voltage and each phase current test signal, ensure that standard calibration device exists
Metering accuracy when frequency test signal fluctuates.
Further preferably, per mutually there is 4 conditioning branches, conditioning branch includes second modulate circuit：Buffer, amplification
Device, filter circuit and drive circuit are formed；The output of current sampling unit is connected with the input of buffer, and buffer is used to reduce
The influence that input impedance exports current sampling unit；The output of buffer connects through amplifier amplification and the input of filter circuit
Connect, the output of wave filter and drive circuit input connection, drive circuit output signal driving AD conversion unit.
To a certain phase current test signal, the amplification factor of amplifier is different in 4 conditioning branches；Current test signal
4 conditioning branch conditionings are passed sequentially through, are AD converted by the second AD conversion unit, MCU stores transformed digital signal
And handle, 4 groups of data are obtained within a sampling period；By 4 groups of data of current a cycle, MCU calculates 4 electric currents
Average value I1、I2、I3And I4；Standard calibration device sets 4 current ranges, is respectively (I1min~I1max)、(I2min~I2max)、
(I13min~I3max) and (I4min~I4max)；By judging I1、I2、I3And I4Whether in selected range of previous sampling period
In the range of, MCU selects corresponding one group of data to calculate electric energy in 4 groups of data；Three-phase current test signal does same place
Reason, ensure that accurate measurement of the standard calibration device in test signal amplitude fluctuations.
The beneficial effects of the utility model are：The utility model provides a kind of intelligent electric energy for being adapted to exceptional operating conditions
Table verifying attachment, using the device build reflection electric energy meter exceptional operating conditions test signal waveform, obtain frequency fluctuation and
The test signal of amplitude fluctuations, realizes accurate measurement of the standard calibration device in this test signal, can detect electric energy meter special
Meter characteristic under operating condition.
Brief description of the drawings
Fig. 1 is the principle of device schematic diagram of the utility model；
Fig. 2 is the structure chart of modulate circuit；
Fig. 3 is the method flow diagram for the intelligent electric energy meter test that exceptional operating conditions are carried out by the utility model；
Fig. 4 is the flow chart for the test signal waveform that reflection electric energy meter exceptional operating conditions are built by the utility model.
Embodiment
The utility model is described in further detail with embodiment below in conjunction with the accompanying drawings：
It is the principle of device schematic diagram of the utility model shown in Fig. 1, a kind of intelligent electric energy meter detection device, including：Signal
Generator, DSP, count comparator, frequency dividing setting unit, isolated location, three-phase standard voltage source, three-phase normalized current source and mark
Quasi- calibrator.Signal generator is connected by communication interface A with DSP output terminals；The input of the output terminal and count comparator of DSP
End connection, the output terminal of DSP are connected with the input terminal of three-phase standard voltage source and the input terminal in three-phase normalized current source at the same time；Meter
Number comparators output terminal be connected with isolated location, isolated location export while and standard calibration device in the first AD conversion list
Member and the connection of the second AD conversion unit；Frequency dividing setting unit output is connected with count comparator control terminal；Signal generator it is defeated
Go out and be connected through communication interface B with three-phase standard voltage source and three-phase normalized current source；The voltage port of standard calibration device is with being tested
The corresponding voltage port of table is in parallel；Connect with the corresponding current port of tested table the electric current port of standard calibration device；Three-phase standard
Voltage source output voltage test signal, output port are connected with standard calibration device corresponding voltage port；Three-phase normalized current source is defeated
Go out current test signal, output port is connected with standard calibration device corresponding current port.
Standard calibration device, including：Voltage sampling unit, current sampling unit, the first modulate circuit, the second modulate circuit,
First AD conversion unit, the second AD conversion unit and MCU；The output of three-phase standard voltage source and the input of voltage sampling unit connect
Connect, the output of voltage sampling unit is connected with the input of the first modulate circuit, the output of the first modulate circuit and the first AD conversion unit
Input connection；The output of first AD conversion unit is connected with MCU；The output in three-phase normalized current source and current sampling unit
Input connection, the output of current sampling unit are connected with the input of the second modulate circuit, and the output of the second modulate circuit turns with the 2nd AD
Change the input connection of unit；The output of second AD conversion unit is connected with MCU.
Signal generator by from n × m data of waveform extracting by PORT COM B be transferred to three-phase standard voltage source and
Three-phase normalized current source simultaneously stores；Signal generator is by each phase voltage and the time interval of each phase current test signal waveform extracting
Ti/ m values are transferred to DSP, and DSP is according to time interval Ti/ m output control pulses, control three-phase standard voltage source and three-phase standard electric
Stream source carries out DA conversions to the data of storage, is amplified by filtering process and signal, exports required each phase voltage and each mutually electricity
Current test signal.
The pulse signal that frequency dividing setting unit control count comparator exports DSP is according to n:1 ratio is divided, and is passed through
Isolated location output pulse signal, controls the first AD conversion unit in standard calibration device and the second AD conversion unit to carry out AD and turn
Change so that standard calibration device can realize the fully synchronized sampling to each phase voltage and each phase current test signal, ensure that standard
Metering accuracy of the calibrator when frequency test signal fluctuates.
Fig. 2 is the structure chart of modulate circuit, for A phase current test signals；The times magnification of amplifier in 4 conditioning branches
Number is different, is respectively A1、A2、A3And A4；4 conditioning branch conditionings are passed sequentially through, carrying out AD by the second AD conversion unit turns
Change, transformed digital signal is stored and handled by MCU, and 4 groups of corresponding datas are obtained within a sampling period；By current
4 groups of data Q of a cycle1、Q2、Q3And Q4, 4 current average I of MCU calculating1、I2、I3And I4；Standard calibration device sets 4
Current range, is respectively (I1min~I1max)、(I2min~I2max)、(I13min~I3max) and (I4min~I4max)；Adopted Ru previous
Sample cycle selected range ability is (I1min~I1max), judge I2In (I1min~I1max) scope, MCU selections corresponding one
Group data Q2Calculate electric energy；B phases and C phase currents test signal do same processing, ensure that standard calibration device is believed in test
Accurate measurement during number amplitude fluctuations.
Fig. 3 is using the intelligent electric energy meter test method flow chart of the utility model progress exceptional operating conditions, Yi Zhongshi
It should be comprised the following steps that in the intelligent electric energy meter test method of exceptional operating conditions：
Step 1：Tested table is in parallel with the voltage circuit of standard calibration device, current circuit series connection；
Step 2：The voltage output port of signal generator is connected with tested table corresponding voltage port, current output terminal mouth with
Tested table corresponding current port connection；
Step 3：Structure can reflect the test signal waveform of electric energy meter exceptional operating conditions；
Step 4：Signal generator can be reflected according to the specification and model arrange parameter of tested table by signal generator output
Frequency fluctuation and the test signal of amplitude fluctuations；Generator output voltage test signal, according to the load characteristic of simulation, if
Put power factor θ, output current test signal；
Step 5：In sufficiently long time interval Δ t, electric energy E is counted according to standard calibration device1Electricity is counted with tested table
Can E2, obtain relative error
Step 6：If the frequency fluctuation limits of error are vbase, the worst error allowed under the influence of frequency fluctuation changes into
vf, the worst error allowed under the influence of amplitude fluctuations changes into vI, obtain under special operation condition, be tested Watch Error limit
Step 7：Judge whether γ is not more than v；Met the requirements if so, being then tested table；It is unsatisfactory for wanting if it is not, being then tested table
Ask.
Fig. 4 is the flow chart for the test signal waveform that reflection electric energy meter exceptional operating conditions are built by the utility model,
Structure can reflect that the method for the test signal waveform of electric energy meter exceptional operating conditions is as follows：
Step 1：The round-trip of test signal reflection frequency is fluctuated and with periodicity, if its function expression is f (t), week
Phase is T；Waveform in one cycle is made of n cycle, and wherein n is the positive integer not less than 2；I-th (1≤i≤n) a week
The function expression of ripple is fi(t), its frequency is fi, cycle Ti=1/fi；Meet formula (1):
0.98fnom≤fi≤1.02fnom (1)
In formula (1), fnomFor reference frequency；
In 0≤t≤Tn, i.e., in one cycle shown in the expression formula of f (t) such as formula (2)：
For the test waveform of structure in a cycle, frequency will be followed successively by f1, f2..., fn-1, fn, constitute the ripple of frequency
It is dynamic.
Step 2：To form frequency fluctuation test signal, i-th of cycle f of each phase voltage test signali(t) function table
It is respectively up to formula：
Wherein, uai(t)、ubi(t)、uci(t) it is respectively a phases, b phases and c phase voltage test signals；M believes for each voltage tester
The virtual value of number each all wave amplitudes；
Step 3：If power factor is θ, then i-th of cycle f of each phase current test signali(t) function expression point
It is not：
Wherein, iai(t)、ibi(t)、ici(t) it is respectively a phases, b phases and c phase current test signals；NiBelieve for testing current
The virtual value of number i-th week wave amplitude；
Have for signal frequency fluctuation in reflection circuit and the simultaneous situation of amplitude fluctuations, each phase current test signal
Shown in the expression formula of valid value N such as formula (9)：
Ni=qiN (9)
Wherein, qiFor amplitude variation coefficient, N is amplitude reference value；
Step 4：In fi(t) a cycle TiOn with constant duration Ti/ m takes m point successively, and j-th point of value is fi
(jTi/m)；Value is carried out successively to n cycle for forming each voltage and current test signal, each voltage and current is tested
For signal, there is n × m value altogether；
Step 5：According to time interval TiN × m described in extraction step 4 is worth/m successively, forms digital signal；
Step 6：Digital signal progress DA is converted to analog signal；
Step 7：Obtained analog signal is filtered；
Step 8：Amplify filtered signal, obtain testing required each phase voltage and each phase current signal.
Compared with prior art, the beneficial effects of the utility model are：It is adapted to the intelligent electric energy meter of exceptional operating conditions
Test, the test signal waveform of structure reflection electric energy meter exceptional operating conditions, obtains frequency fluctuation and the test of amplitude fluctuations letter
Number, acted on by any frequency divider frequency dividing and a plurality of conditioning branch is set, realize metering of the standard calibration device in this test signal
Accuracy, can detect meter characteristic of the electric energy meter under exceptional operating conditions.
Undeclared part involved in the utility model is same as the prior art or is realized using the prior art.
Claims (3)
1. a kind of intelligent electric energy meter detection device, it is characterized in that：Set including signal generator, DSP, count comparator, frequency dividing
Unit, isolated location, three-phase standard voltage source, three-phase normalized current source and standard calibration device；Signal generator is connect by communication
Mouth A is connected with DSP output terminals；The output terminal of DSP is connected with the input terminal of count comparator, the output terminal of DSP while and three-phase
The input terminal of standard voltage source is connected with the input terminal in three-phase normalized current source；The output terminal of count comparator connects with isolated location
Connect, the output of isolated location is connected with the first AD conversion unit in standard calibration device and the second AD conversion unit at the same time；Frequency dividing
Setting unit output is connected with count comparator control terminal；The output of signal generator is through communication interface B and three-phase normal voltage
Source and the connection of three-phase normalized current source；The voltage port of standard calibration device is in parallel with the corresponding voltage port of tested table；Standard school
Connect with the corresponding current port of tested table the electric current port of quasi- device；Three-phase standard voltage source output voltage test signal, output
Port is connected with standard calibration device corresponding voltage port；Three-phase normalized current source output current test signal, output port and mark
Quasi- calibrator corresponding current port connection.
2. intelligent electric energy meter detection device according to claim 1, it is characterized in that：The standard calibration device includes：Voltage
Sampling unit, current sampling unit, the first modulate circuit, the second modulate circuit, the first AD conversion unit, the second AD conversion unit
And MCU；The output of three-phase standard voltage source and the input of voltage sampling unit connect, and the output of voltage sampling unit is adjusted with first
Circuit input connection is managed, the output of the first modulate circuit is connected with the input of the first AD conversion unit；First AD conversion unit it is defeated
Go out and be connected with MCU；The output in three-phase normalized current source and the input of current sampling unit connect, the output of current sampling unit with
The input connection of second modulate circuit, the output of the second modulate circuit are connected with the input of the second AD conversion unit；Second AD conversion list
The output of member is connected with MCU.
3. intelligent electric energy meter detection device according to claim 2, it is characterized in that：Second modulate circuit is every mutually to be had
4 conditioning branches, conditioning branch include：Buffer, amplifier, filter circuit and drive circuit are formed；Current sampling unit
Output is connected with the input of buffer, and buffer is used to reduce the influence that input impedance exports current sampling unit；Buffer
Output amplify through amplifier and be connected with the input of filter circuit, the output of wave filter and drive circuit input connection, drive electric
Road output signal driving AD conversion unit.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| CN110471023A (en) * | 2019-08-02 | 2019-11-19 | 珠海科盈自动化***有限公司 | A kind of test fixture and method of Direct Current Instrument |
| CN114545068A (en) * | 2021-12-22 | 2022-05-27 | 云南电网有限责任公司电力科学研究院 | Portable 10kV three-phase broadband power standard equipment |
| CN116500536A (en) * | 2023-04-14 | 2023-07-28 | 南京丹迪克电力仪表有限公司 | Method for electric energy meter direct current and even harmonic influence test and alternating current-direct current electric energy meter testing device |
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2017
- 2017-09-26 CN CN201721236239.4U patent/CN207366731U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| CN110471023A (en) * | 2019-08-02 | 2019-11-19 | 珠海科盈自动化***有限公司 | A kind of test fixture and method of Direct Current Instrument |
| CN114545068A (en) * | 2021-12-22 | 2022-05-27 | 云南电网有限责任公司电力科学研究院 | Portable 10kV three-phase broadband power standard equipment |
| CN116500536A (en) * | 2023-04-14 | 2023-07-28 | 南京丹迪克电力仪表有限公司 | Method for electric energy meter direct current and even harmonic influence test and alternating current-direct current electric energy meter testing device |
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