CN102035554A - System and method for metering and analyzing electric energy as well as analog-to-digital conversion circuit - Google Patents

System and method for metering and analyzing electric energy as well as analog-to-digital conversion circuit Download PDF

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CN102035554A
CN102035554A CN2010105546589A CN201010554658A CN102035554A CN 102035554 A CN102035554 A CN 102035554A CN 2010105546589 A CN2010105546589 A CN 2010105546589A CN 201010554658 A CN201010554658 A CN 201010554658A CN 102035554 A CN102035554 A CN 102035554A
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value
sampling unit
subharmonic
electric energy
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CN102035554B (en
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张斌阳
张明雄
张志勇
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HI-TREND TECHNOLOGY (SHANGHAI) Co Ltd
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HI-TREND TECHNOLOGY (SHANGHAI) Co Ltd
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Abstract

The invention discloses a system and a method for metering and analyzing electric energy as well as an analog-to-digital conversion circuit, belonging to the field of intelligent grid. In the invention, two sampling units are simultaneously connected behind a sigma-delta modulation unit, wherein the D value of the first sampling unit is fixed for metering the electric energy and the D value of the second sampling unit is variable for analyzing sub-harmonic waves so as to improve the monitoring stability of the sub-harmonic waves and ensure the accuracy for metering the electric energy in the cost of less hardware. During variation of the grid frequency, the D value of the second sampling unit is automatically calculated and adjusted to realize self-adaptive adjustment and maintain the monitoring stability of sub-harmonic waves. Coefficient compensation is performed on the harmonic component in the second sampling unit so as to avoid attenuation of a transition zone of a medium-high frequency part resulting from using a 3-order CIC (Cascaded Integrator Comb) filter.

Description

Electric energy metrical and analytical system, method and analog to digital conversion circuit
Technical field
The present invention relates to the intelligent grid field, particularly electric energy metrical and subharmonic analytical technology in the intelligent grid.
Background technology
Along with the greatly developing of intelligent grid, people more and more pay close attention to the quality problems of real-time power network operation in recent years, and then the cry that subharmonic is analyzed is also more and more higher.
Alleged subharmonic is a kind of of harmonic wave among the present invention, and its frequency is the N of fundamental frequency, and N is an integer.
At present, the fourier spectrum analysis of most Scheme Choice main flows that subharmonic is analyzed, but in real world applications, exist the problem that insoluble sampling rate can't be synchronous with mains frequency.
The network operation frequency of China is 50Hz, near yet the fluctuation to some extent standard power frequency usually of the mains frequency in the actual motion, the frequency fluctuation of this point point makes the fixed sample system unable to do what one wishes just, be directly used in the subharmonic analysis as not taking measures, will cause very large error and can't normally use.
Segmentation scheme adopts the mode of building peripheral hardware, obtain the zero crossing information of waveform with comparator, by hardware phase-locked-loop (Phase Lock Loop, be called for short " PLL ") frequency doubly is raised to enough two-forties, remove to drive analog to digital converter (Analog Digital Converter again, be called for short " ADC ") sampling clock, and then reached the actual effect that synchronization is sampled.
When the external electrical network frequency is offset, comparator is realized the variation of zero crossing, and PLL also will carry out the stabilization process of a frequency locking again, and the data of ADC are only the valid data that true synchronization is crossed afterwards, whenever frequency fluctuates, process described above can be run once again.Shortcoming is that the real-time synchronous effect of this type of scheme is also not ideal enough, error tracking can appear in the occasion that often fluctuates in frequency, simultaneously, the system hardware dependence is big, structure complexity is big, product cost is too high, is not suitable for promoting in the low-cost application of electric energy meter etc.
Summary of the invention
The object of the present invention is to provide a kind of electric energy metrical and analytical system, method and analog to digital conversion circuit,, both improved subharmonic monitoring stability, guaranteed the accuracy of electric energy metrical again with the less hardware cost.
For solving the problems of the technologies described above, embodiments of the present invention provide a kind of analog to digital conversion circuit, comprising:
∑-Δ modulating unit is used for the analog signal of input is carried out the single-bit sampling;
First sampling unit is used for that the single-bit sampled signal of ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, and the output power supply can be measured the digital signal of using, and the D value of first sampling unit immobilizes;
Second sampling unit is used for that the single-bit sampled signal of ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, the digital signal that output is used for the subharmonic analysis, and the D value of second sampling unit is variable;
Wherein, D=FS/fs, FS are the sampling rate of ∑-Δ modulating unit, and fs is the extraction speed of sampling unit.
Embodiments of the present invention also provide a kind of electric energy metrical and analytical system, comprise analog to digital conversion circuit, electric energy metrical unit and subharmonic analytic unit, wherein,
Analog to digital conversion circuit comprises:
∑-Δ modulating unit is used for the analog signal of input is carried out the single-bit sampling;
First sampling unit is used for that the single-bit sampled signal of ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, and the output power supply can be measured the digital signal of using, and the D value of first sampling unit immobilizes;
Second sampling unit is used for that the single-bit sampled signal of ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, the digital signal that output is used for the subharmonic analysis, and the D value of second sampling unit is variable;
Wherein, D=FS/fs, FS are the sampling rate of ∑-Δ modulating unit, and fs is the extraction speed of sampling unit;
The electric energy metrical unit is used for carrying out electric energy metrical according to the digital signal of first sampling unit output;
The subharmonic analytic unit is used for carrying out the subharmonic analysis according to the digital signal of second sampling unit output.
Embodiments of the present invention also provide a kind of electric energy metrical and analytical method, may further comprise the steps:
Steps A is carried out the single-bit sampling to the analog signal of input, obtains the single-bit sampled signal;
Step B carries out the fixing reduction of speed of D value to the single-bit sampled signal and extracts and low-pass filtering, uses the digital signal that obtains to power and can measure;
Step C carries out the variable reduction of speed of D value to the single-bit sampled signal and extracts and low-pass filtering, uses the digital signal that obtains to carry out the subharmonic analysis;
Step B and step C be executed in parallel after steps A.
Embodiment of the present invention compared with prior art, the main distinction and effect thereof are:
Behind a ∑-Δ modulating unit, connect two sampling units simultaneously, one of them D value is fixing, and another D value is variable for the subharmonic analysis for electric energy metrical, thereby with the less hardware cost, both improve subharmonic monitoring stability, guaranteed the accuracy of electric energy metrical again.
Further, when mains frequency changes, calculate and adjust the D value of second sampling unit automatically, can adjust adaptively, make the subharmonic monitoring remain stable.
Further, in second sampling unit, harmonic component is carried out compensating coefficient, can remedy medium-high frequency part transition band decay because of using 3 rank cic filters to cause.The actual test of this scheme is respond well, to the voltage and current signal of electrical network, can satisfy in 2 to 21 subharmonic scopes, reaches 5% subharmonic analysis precision, also can extrapolate useful parameters such as irregularity of wave form simultaneously.
Further, when the D value changes, abandon the still unstabilized data of top n, can make the result of subharmonic monitoring more accurate.Through experiment repeatedly, both can guarantee the stability of subharmonic monitoring result during N=4, can make the break period of subharmonic monitoring the shortest again.
Description of drawings
Fig. 1 is the structural representation of a kind of analog to digital conversion circuit in the first embodiment of the invention;
Fig. 2 is the structural representation of a kind of analog to digital conversion circuit in the second embodiment of the invention;
Fig. 3 is the structural representation of a kind of electric energy metrical and analytical system in the fifth embodiment of the invention;
Fig. 4 is the structural representation of another kind of electric energy metrical and analytical system in the fifth embodiment of the invention;
Fig. 5 is the schematic flow sheet of a kind of electric energy metrical and analytical method in the sixth embodiment of the invention.
Embodiment
In the following description, in order to make the reader understand the application better many ins and outs have been proposed.But, persons of ordinary skill in the art may appreciate that even without these ins and outs with based on the many variations and the modification of following each execution mode, also can realize each claim of the application technical scheme required for protection.
For making the purpose, technical solutions and advantages of the present invention clearer, embodiments of the present invention are described in further detail below in conjunction with accompanying drawing.
First embodiment of the invention relates to a kind of analog to digital conversion circuit.Fig. 1 is the structural representation of this analog to digital conversion circuit.This analog to digital conversion circuit comprises:
∑-Δ modulating unit is used for the analog signal of input is carried out the single-bit sampling.
First sampling (Decimation) unit is used for that the single-bit sampled signal of ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, and the output power supply can be measured the digital signal of using, and the D value of first sampling unit immobilizes.
Second sampling unit is used for that the single-bit sampled signal of ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, the digital signal that output is used for the subharmonic analysis, and the D value of second sampling unit is variable.
Wherein, D=FS/fs, FS are the sampling rate of ∑-Δ modulating unit, and fs is the extraction speed of sampling unit.Two sampling units carry out reduction of speed and extract and low-pass filtering, obtain low sampling rate but more high-precision adc data, and it is to make full use of average effect in essence, changes precision with speed.
Behind a ∑-Δ modulating unit, connect two sampling units simultaneously, one of them D value is fixing, and another D value is variable for the subharmonic analysis for electric energy metrical, thereby with the less hardware cost, both improve subharmonic monitoring stability, guaranteed the accuracy of electric energy metrical again.
The high-speed sampling clock FS of modulator, generally provide by crystal oscillating circuit, provide such as the 1.8432MHz that obtains by 5.5296MHz crystal three frequency division, note high speed bit stream speed FS and low speed extract the ratio D=FS/fs of speed fs in the embodiment of the present invention, on the fixed sample rate path that electric energy metrical partly requires, immobilize after D value design is selected, for convenient the application generally got 2 power time (as 32,64,128 etc.); And in order to follow the tracks of the variation of external electrical network frequency f in, on the basis that keeps the normal energy metering, we are second sampling unit of the parallel increase in the rear end of each modulator, it is adjustable simultaneously its D value to be designed to software, purpose is to wish when the electrical network sinusoidal signal frequency fluctuates, total energy keeps 64 collection points in each cycle, must satisfy relational expression fs=64*fin so, can obtain D=FS/ (64*fin) by top two formulas, certainly also need the D value got and round up, so must be integer because it represents extraction yield.From here as can be seen, as long as by adjusting the D value simply, promptly can realize synchronously with the external electrical network frequency, obtain weekly ripple and fix 64 sampled data, data synchronously can relievedly be done fast Fourier transform (Fast Fourier Transform is called for short " FFT ") conversion, just obtain the real frequency spectrum of power network signal, synchronizing process recited above has significantly reduced the spectrum leakage effect that the Fourier harmonic analysis is produced, thereby has also improved the accuracy of detection of subharmonic.
The technical program under mains frequency fluctuation situation, has improved subharmonic monitoring stability guaranteeing just to provide synchronization data by simple change under the impregnable prerequisite of electric energy metrical.And effectively utilized the design feature (being ∑-Δ modulating unit+first sampling unit) of existing sigma-delta ADC, only increased the sampling unit (being the DEC filter) that is easy to realize, compare with the PLL+ADC scheme of prior art, significantly reduced hardware spending and reduced cost.
First, second does not have the implication of order, priority or grade in alleged first sampling unit of the present invention, second sampling unit, represents that just this is two different sampling units.
Second embodiment of the invention relates to a kind of analog to digital conversion circuit.Fig. 2 is the structural representation of this analog to digital conversion circuit.
Second execution mode improves on the basis of first execution mode, main improvements are: when mains frequency changes, automatically calculate and adjust the D value of second sampling unit, thereby can realize the self adaptation adjustment, make the subharmonic monitoring remain stable.Specifically, second execution mode has increased mains frequency detecting unit and D value computing unit with respect to first execution mode, wherein:
The mains frequency detecting unit is used for detecting in real time current mains frequency (fin).The detection of accomplished in many ways mains frequency can be arranged, and for example the multicycle zero crossing counting method of average utilizes the sign change of neighbouring sample point to detect zero crossing, then by recording repeatedly the equispaced of zero-crossing timing, just can push away the power network signal frequency.And for example, allow sampled signal obtain square-wave signal by analog comparator, window enable counter when making of square-wave signal, by count value also can push away frequency.Or the like.
D value computing unit is used to calculate the value of FS/ (Y*fin), and result of calculation is rounded, and obtains the D value, is set to second sampling unit, and wherein Y is 2 P power, and P is predefined greater than 3 integer, and fin is the detected mains frequency of mains frequency detecting unit.Preferably, can adopt the mode that rounds up to round, also can make otherwise to round, as block, advance one or the like.
Can periodically be set to second sampling unit to D value with D value computing unit gained, also can be only after the mains frequency detecting unit detects current mains frequency and changes, the D value with D value computing unit gained is set to second sampling unit again.In each execution mode of the present invention, the mains frequency variation that is meant mains frequency that changes reaches predefined thresholding, if change less than thresholding, thinks then not change that this is that too small fluctuation can be ignored because may there be error in system itself.
In some other execution mode of the present invention, the D value of second sampling unit also can manual change, just import a value when needed and give second sampling unit, this variation that relatively is fit to mains frequency seldom, or the situation of artificial control.The operator can manually be provided with a suitable value for second sampling unit after mains frequency changes.
Third embodiment of the invention relates to a kind of analog to digital conversion circuit.
The 3rd execution mode improves on the basis of first or second execution mode, main improvements are: in second sampling unit harmonic component is carried out compensating coefficient, can remedy the medium-high frequency part transition band decay that causes because using 3 rank cascaded integrator-comb (Cascade-integrator-Comb is called for short " CIC ") filter.Specifically:
Comprise in second sampling unit:
3 rank cic filters are used to realize filtering extraction.
Compensating unit is used for each harmonic component of 3 rank cic filter outputs is done the multiplication compensation.Adopt the benefit of 3 rank cic filters do not need to be multiplier to realize simply, but can produce the transition band decay by the centering HFS, the amplitude that to see harmonic wave part on the frequency spectrum is subjected to the influence of falling to a certain degree, so need obtain frequency spectrum and carry out the post-compensation operation done the Flourier conversion by synchronized data.At first ignore insignificant DC component, according to following formula harmonic component is done multiplication compensation (with the multiplication of H (K) with the K subharmonic) then, for example can select this frequency of fin=50Hz calculate the corresponding calculated value of each harmonic (as 2 to 21 times), get its inverse and be saved as fixed table as offset
H(K)={sin(D*π*fin*K/FS)/sin(π*fin*K/FS)/D}^3
Sin () represents sine trigonometric function, and π represents circumference ratio, and ^ represents power time computing, and fin is a mains frequency, and K is the positive integer greater than 1, and K represents the K subharmonic of fin, and H (K) is the penalty coefficient to the K subharmonic.
The actual test of this scheme is respond well, to the voltage and current signal of electrical network, can satisfy in 2 to 21 subharmonic scopes, reaches 5% subharmonic analysis precision, also can extrapolate useful parameters such as irregularity of wave form simultaneously.
The technical program is fallen at the medium-high frequency decay of sampling unit, and the simple software compensation method is provided, and makes the accuracy of detection of high order harmonic component obtain to guarantee.
Four embodiment of the invention relates to a kind of analog to digital conversion circuit.
The 4th execution mode improves on the basis of first, second or the 3rd execution mode, and main improvements are: second sampling unit abandons top n data to be exported when set D value variation, N is predefined positive integer.Here the variation of D value can be (as second execution mode) that initiation is set automatically, also can be that initiation manually is set.
When the D value changed, abandoning the still unstabilized script of top n will can make the result of subharmonic monitoring more accurate for the data of subharmonic analysis use.
Usually, electrical network power frequency 50Hz existence is no more than 10% fluctuation, certainly for some national 60Hz that adopts, this method is suitable for too, like this frequency range maximum 45 to 66Hz, when monitoring foreign frequency generation skew, can pass through automated manner (formula association) or manual mode (user's setting), make extraction yield D value that the variation of tracing property take place, this moment, second sampling unit needed certain stabilization time, recommendation abandons preceding 4 still unstabilized data, both can guarantee the stability of subharmonic monitoring result, can make the break period of subharmonic monitoring the shortest again.
Can also comprise a buffer in second sampling unit, be used for buffer memory data to be exported, the buffer memory of this buffer reaches behind the predetermined threshold again with the batch processing mode dateout.
Certainly, also can not comprise buffer in second sampling unit, not treat dateout and carry out buffer memory, once the satisfactory dateout output in real time for the treatment of is arranged, the benefit of this scheme is the time delay minimum.
Fifth embodiment of the invention relates to a kind of electric energy metrical and analytical system.
This system comprises:
As each described analog to digital conversion circuit in first to fourth execution mode;
The electric energy metrical unit is used for carrying out electric energy metrical according to the digital signal of analog to digital conversion circuit first sampling unit output.
The subharmonic analytic unit is used for carrying out the subharmonic analysis according to the digital signal of analog to digital conversion circuit second sampling unit output.
Fig. 3, Fig. 4 are the structural representations of two examples of this electric energy metrical and analytical system, and wherein the AD conversion unit among Fig. 3 has adopted the structure of first execution mode, and the AD conversion unit among Fig. 4 has adopted the structure in second execution mode.
Be appreciated that whole system can realize, also can divide in the polylith chip and realize in a chip.
Sixth embodiment of the invention relates to a kind of electric energy metrical and analytical method.Fig. 5 is the schematic flow sheet of this electric energy metrical and analytical method.
In step 501, the analog signal of input is carried out the single-bit sampling, obtain the single-bit sampled signal.After this enter parallel step 502 and 504.
In step 502, the single-bit sampled signal is carried out the fixing reduction of speed of D value extract and low-pass filtering, obtain digital signal.
After this enter step 503, the digital signal of using step 502 to obtain is powered and can be measured.
In step 504, the single-bit sampled signal is carried out the variable reduction of speed of D value extract and low-pass filtering, obtain digital signal.
After this enter step 505, the digital signal of using step 504 to obtain is carried out the subharmonic analysis.
Present embodiment is and the corresponding method execution mode of first execution mode, present embodiment can with the enforcement of working in coordination of first execution mode.The correlation technique details of mentioning in first execution mode is still effective in the present embodiment, in order to reduce repetition, repeats no more here.Correspondingly, the correlation technique details of mentioning in the present embodiment also can be applicable in first execution mode.
Seventh embodiment of the invention relates to a kind of electric energy metrical and analytical method.
The 7th execution mode improves on the basis of the 6th execution mode, main improvements are: when mains frequency changes, automatically calculate and adjust the D value of second sampling unit, thereby can realize the self adaptation adjustment, make the subharmonic monitoring remain stable.
Specifically, also exist with Fig. 5 in the parallel following steps of flow process:
Detect current mains frequency fin in real time.
Round after calculating FS/ (Y*fin), obtain D value, this D value is for reduction of speed extraction in the step 504 and low-pass filtering use, and wherein Y is 2 P power, and P is predefined greater than 3 integer, and fin is the detected mains frequency of mains frequency detecting unit.
Present embodiment is and the corresponding method execution mode of second execution mode, present embodiment can with the enforcement of working in coordination of second execution mode.The correlation technique details of mentioning in second execution mode is still effective in the present embodiment, in order to reduce repetition, repeats no more here.Correspondingly, the correlation technique details of mentioning in the present embodiment also can be applicable in second execution mode.
Eighth embodiment of the invention relates to a kind of electric energy metrical and analytical method.
The 8th execution mode improves on the basis of the 6th or the 7th execution mode, and main improvements are, the harmonic component in extraction of step 504 reduction of speed and the low-pass filtering treatment is carried out compensating coefficient.Specifically, in the reduction of speed extraction and low-pass filtering process of step 504, also comprise following substep:
Reduction of speed is extracted and the data of low-pass filtering gained are carried out fast fourier transform and obtained frequency spectrum, the coefficient of each harmonic component in the frequency spectrum is multiplied each other with the bucking-out system of following formula calculating gained respectively:
H(K)={sin(D*π*fin*K/FS)/sin(π*fin*K/FS)/D}^3
Sin () represents sine trigonometric function, and π represents circumference ratio, and ^ represents power time computing, and fin is a mains frequency, and K is the positive integer greater than 1, and K represents the K subharmonic of fin, and H (K) is the penalty coefficient to the K subharmonic.In order to accelerate arithmetic speed, the value of various H (K) can precompute, and exists in the table, directly uses when needing.
Present embodiment is and the corresponding method execution mode of the 3rd execution mode, present embodiment can with the enforcement of working in coordination of the 3rd execution mode.The correlation technique details of mentioning in the 3rd execution mode is still effective in the present embodiment, in order to reduce repetition, repeats no more here.Correspondingly, the correlation technique details of mentioning in the present embodiment also can be applicable in the 3rd execution mode.
Ninth embodiment of the invention relates to a kind of electric energy metrical and analytical method.
The 9th execution mode improves on the basis of the 6th, the 7th or the 8th execution mode, main improvements are, in the reduction of speed extraction and low-pass filtering process of step 504, if the D value changes, then abandon the data that top n is used for the subharmonic analysis, N is predefined positive integer.
Preferably, N=4.
Present embodiment is and the corresponding method execution mode of the 4th execution mode, present embodiment can with the enforcement of working in coordination of the 4th execution mode.The correlation technique details of mentioning in the 4th execution mode is still effective in the present embodiment, in order to reduce repetition, repeats no more here.Correspondingly, the correlation technique details of mentioning in the present embodiment also can be applicable in the 4th execution mode.
Each method execution mode of the present invention all can be realized in modes such as software, hardware, firmwares.No matter the present invention be with software, hardware, or the firmware mode realize, instruction code can be stored in the memory of computer-accessible of any kind (for example permanent or revisable, volatibility or non-volatile, solid-state or non-solid-state, fixing or removable medium or the like).Equally, memory can for example be programmable logic array (Programmable Array Logic, be called for short " PAL "), random access memory (Random Access Memory, be called for short " RAM "), programmable read only memory (Programmable Read Only Memory, be called for short " PROM "), read-only memory (Read-Only Memory, be called for short " ROM "), Electrically Erasable Read Only Memory (Electrically Erasable Programmable ROM, be called for short " EEPROM "), disk, CD, digital versatile disc (Digital Versatile Disc is called for short " DVD ") or the like.
Though pass through with reference to some of the preferred embodiment of the invention, the present invention is illustrated and describes, but those of ordinary skill in the art should be understood that and can do various changes to it in the form and details, and without departing from the spirit and scope of the present invention.

Claims (12)

1. an analog to digital conversion circuit is characterized in that, comprising:
∑-Δ modulating unit is used for the analog signal of input is carried out the single-bit sampling;
First sampling unit is used for that the single-bit sampled signal of described ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, and the output power supply can be measured the digital signal of using, and the D value of first sampling unit immobilizes;
Second sampling unit is used for that the single-bit sampled signal of described ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, the digital signal that output is used for the subharmonic analysis, and the D value of second sampling unit is variable;
Wherein, D=FS/fs, FS are the sampling rate of described ∑-Δ modulating unit, and fs is the extraction speed of sampling unit.
2. analog to digital conversion circuit according to claim 1 is characterized in that, also comprises:
The mains frequency detecting unit is used for detecting in real time current mains frequency;
D value computing unit rounds after being used to calculate FS/ (Y*fin), obtains the D value, is set to described second sampling unit, and wherein Y is 2 P power, and P is predefined greater than 3 integer, and fin is the detected mains frequency of described mains frequency detecting unit.
3. analog to digital conversion circuit according to claim 1 is characterized in that, comprises in described second sampling unit:
3 classes connection integral comb filter is used to realize filtering extraction;
Compensating unit is used for according to following formula each harmonic component of described 3 classes connection integral comb filter output being done the multiplication compensation:
H(K)={sin(D*π*fin*K/FS)/sin(π*fin*K/FS)/D}^3
Sin () represents sine trigonometric function, and π represents circumference ratio, and ^ represents power time computing, and fin is a mains frequency, and K is the positive integer greater than 1, and K represents the K subharmonic of fin, and H (K) is the penalty coefficient to the K subharmonic.
4. according to each described analog to digital conversion circuit in the claim 1 to 3, it is characterized in that when described second sampling unit changes in set D value, abandon top n data to be exported, N is predefined positive integer.
5. analog to digital conversion circuit according to claim 4 is characterized in that, described N=4.
6. analog to digital conversion circuit according to claim 4 is characterized in that, also comprises a buffer in described second sampling unit, is used for buffer memory data to be exported, and the buffer memory of this buffer reaches behind the predetermined threshold again with the batch processing mode dateout.
7. electric energy metrical and analytical system is characterized in that, comprise analog to digital conversion circuit, electric energy metrical unit and subharmonic analytic unit, wherein,
Analog-digital conversion circuit as described comprises:
∑-Δ modulating unit is used for the analog signal of input is carried out the single-bit sampling;
First sampling unit is used for that the single-bit sampled signal of described ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, and the output power supply can be measured the digital signal of using, and the D value of first sampling unit immobilizes;
Second sampling unit is used for that the single-bit sampled signal of described ∑-Δ modulating unit output is carried out reduction of speed and extracts and low-pass filtering, the digital signal that output is used for the subharmonic analysis, and the D value of second sampling unit is variable;
Wherein, D=FS/fs, FS are the sampling rate of described ∑-Δ modulating unit, and fs is the extraction speed of described sampling unit;
Described electric energy metrical unit is used for carrying out electric energy metrical according to the digital signal of described first sampling unit output;
Described subharmonic analytic unit is used for carrying out the subharmonic analysis according to the digital signal of described second sampling unit output.
8. electric energy metrical and analytical method is characterized in that, may further comprise the steps:
Steps A is carried out the single-bit sampling to the analog signal of input, obtains the single-bit sampled signal;
Step B carries out the fixing reduction of speed of D value to described single-bit sampled signal and extracts and low-pass filtering, uses the digital signal that obtains to power and can measure;
Step C carries out the variable reduction of speed of D value to described single-bit sampled signal and extracts and low-pass filtering, uses the digital signal that obtains to carry out the subharmonic analysis;
Described step B and step C be executed in parallel after steps A.
9. electric energy metrical according to claim 8 and analytical method is characterized in that, also comprise the following steps parallel with described step C:
Detect current mains frequency in real time;
Round after calculating FS/ (Y*fin), obtain D value, this D value is for extraction of the reduction of speed among the described step C and low-pass filtering use, and wherein Y is 2 P power, and P is predefined greater than 3 integer, and fin is the detected mains frequency of described mains frequency detecting unit.
10. electric energy metrical according to claim 8 and analytical method is characterized in that, in the reduction of speed extraction and low-pass filtering process of described step C, also comprise following substep:
Reduction of speed is extracted and the data of low-pass filtering gained are carried out fast fourier transform and obtained frequency spectrum, the coefficient of each harmonic component in the frequency spectrum is multiplied each other with the bucking-out system of following formula calculating gained respectively:
H(K)={sin(D*π*fin*K/FS)/sin(π*fin*K/FS)/D}^3
Sin () represents sine trigonometric function, and π represents circumference ratio, and ^ represents power time computing, and fin is a mains frequency, and K is the positive integer greater than 1, and K represents the K subharmonic of fin, and H (K) is the penalty coefficient to the K subharmonic.
11. each described electric energy metrical and analytical method in 10 is characterized in that according to Claim 8, the reduction of speed of described step C extract and the low-pass filtering process in, further comprising the steps of:
If the D value changes, then abandon the data that top n is used for the subharmonic analysis, N is predefined positive integer.
12. electric energy metrical according to claim 8 and analytical method is characterized in that, described N=4.
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102890173A (en) * 2012-08-30 2013-01-23 漳州科能电器有限公司 Reactive power measurement method and device capable of improving reactive power error
CN103762983A (en) * 2012-09-07 2014-04-30 联发科技股份有限公司 Delta-sigma analog-to-digital converter
CN104483547A (en) * 2014-11-27 2015-04-01 广东电网有限责任公司电力科学研究院 Method and system for filtering power signal
CN106291096A (en) * 2016-07-20 2017-01-04 中国电力科学研究院 A kind of multistage method for resampling for nonlinear load electric energy meter
CN106936434A (en) * 2017-03-13 2017-07-07 中国电子科技集团公司第二十四研究所 System is corrected based on the code density high-order harmonic wave that FFT is extracted
CN108566204A (en) * 2018-04-19 2018-09-21 南通大学 A kind of adaptive power frequency type double integration A/D converter of integration period for accurate fields of measurement
CN110687348A (en) * 2019-10-29 2020-01-14 四川长虹电器股份有限公司 Electric energy metering device and electric energy metering method
CN110719043A (en) * 2019-11-21 2020-01-21 深圳国能电气有限公司 Inverter harmonic compensation method and control device thereof
CN113189721A (en) * 2021-05-19 2021-07-30 深圳市爱得乐电子有限公司 Photoelectric hybrid module
WO2023005825A1 (en) * 2021-07-30 2023-02-02 合肥市芯海电子科技有限公司 Analog-to-digital converter, electric quantity measurement circuit, and battery management system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9513319B1 (en) 2014-11-25 2016-12-06 Cypress Semiconductor Corporation Systems, methods, and devices for energy and power metering

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1702465A (en) * 2005-06-16 2005-11-30 赵熙华 Universal electric energy meter
CN101403774A (en) * 2008-11-07 2009-04-08 扬州中凌高科技发展有限公司 Harmonic wave analysis method based on non-synchronous sampling

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1702465A (en) * 2005-06-16 2005-11-30 赵熙华 Universal electric energy meter
CN101403774A (en) * 2008-11-07 2009-04-08 扬州中凌高科技发展有限公司 Harmonic wave analysis method based on non-synchronous sampling

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
刘贤锴: "《基于CS5463的便携式电能分析仪设计》", 《化工自动化及仪表》, vol. 36, no. 3, 31 December 2009 (2009-12-31) *

Cited By (14)

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CN102890173A (en) * 2012-08-30 2013-01-23 漳州科能电器有限公司 Reactive power measurement method and device capable of improving reactive power error
CN103762983A (en) * 2012-09-07 2014-04-30 联发科技股份有限公司 Delta-sigma analog-to-digital converter
CN103762983B (en) * 2012-09-07 2017-06-09 联发科技股份有限公司 Delta-sigma analog-to-digital converter
CN104483547A (en) * 2014-11-27 2015-04-01 广东电网有限责任公司电力科学研究院 Method and system for filtering power signal
CN106291096A (en) * 2016-07-20 2017-01-04 中国电力科学研究院 A kind of multistage method for resampling for nonlinear load electric energy meter
CN106936434B (en) * 2017-03-13 2020-10-30 中国电子科技集团公司第二十四研究所 Code density high-order harmonic correction system based on FFT extraction
CN106936434A (en) * 2017-03-13 2017-07-07 中国电子科技集团公司第二十四研究所 System is corrected based on the code density high-order harmonic wave that FFT is extracted
CN108566204A (en) * 2018-04-19 2018-09-21 南通大学 A kind of adaptive power frequency type double integration A/D converter of integration period for accurate fields of measurement
CN110687348A (en) * 2019-10-29 2020-01-14 四川长虹电器股份有限公司 Electric energy metering device and electric energy metering method
CN110687348B (en) * 2019-10-29 2021-04-27 四川长虹电器股份有限公司 Electric energy metering device and electric energy metering method
CN110719043A (en) * 2019-11-21 2020-01-21 深圳国能电气有限公司 Inverter harmonic compensation method and control device thereof
CN110719043B (en) * 2019-11-21 2021-02-05 深圳国能电气有限公司 Inverter harmonic compensation method and control device thereof
CN113189721A (en) * 2021-05-19 2021-07-30 深圳市爱得乐电子有限公司 Photoelectric hybrid module
WO2023005825A1 (en) * 2021-07-30 2023-02-02 合肥市芯海电子科技有限公司 Analog-to-digital converter, electric quantity measurement circuit, and battery management system

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