CN101063695B - Reactive power calculating circuit and method - Google Patents
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Abstract
This invention discloses one computation circuit and its method without power, which comprises the following steps: processing Fourier conversion from current digital signals into voltage digital signals and displacing the converted frequency signal by ninety degrees; then converting the frequency zone signal for Fourier reverse change and then according to the current digital signals or voltage digital signals to compute without power. For base wave and resonance wave current or voltage signals, it realizes its Fourier converted frequency signals for displacement process.
Description
Technical field
The present invention relates to the electric energy metrical technology, particularly a kind of reactive power calculating circuit and a kind of reactive power calculating method.
Background technology
Electric energy metrical is the energy that metering active power takes place, active power P
0Computing formula be:
Wherein, V is a voltage, and I is an electric current, and α is the phase place angle of electric current and voltage.
Fig. 1 is the structural representation of ic for energy metering in the prior art.As shown in Figure 1, existing ic for energy metering generally includes: AD conversion unit 101 and AD conversion unit 102, multiplier 103, energy accumulation unit 104.
In the foregoing circuit, can also comprise other subsidiary function unit such as filtering extraction unit and low-pass filter unit usually.
Can realize the metering of active power by above-mentioned ic for energy metering, and the electricity charge that can this metering user.But, also need accurately to know reactive power for the load quality in the testing circuit.Reactive power P
1Computing formula be:
Wherein, V is a voltage, and I is an electric current, and α is the phase place angle of electric current and voltage.
Based on above-mentioned Formula of Reactive Power, and on the basis that active power is calculated, the existing method of calculating reactive power mainly contains following two kinds:
1, moves the sampled point method: increase a buffer unit between AD conversion unit 101 in ic for energy metering as shown in Figure 1 and the multiplier 103 or between AD conversion unit 102 and the multiplier 103, be used for voltage digital signal is carried out the buffer memory of 1/4 phase cycling, promptly current digital signal or voltage digital signal are carried out the phase shifts of 90 degree, and calculate current digital signal behind the buffer memory or voltage digital signal and the not voltage digital signal of buffer memory or the product of current digital signal.But this method is only applicable to first-harmonic, then can't realize the phase shift of 90 degree to harmonic wave.
2, Hilbert (Hilbert) filter method: the Phase-Shifting Characteristics of utilizing the Hilbert wave filter, to voltage digital signal or current digital signal phase shift 90 degree, and voltage digital signal or the current digital signal of current digital signal and not phase shift or the product of voltage digital signal after the calculating phase shift.But the design of the filter factor of Hilbert wave filter is complicated, the numerical value irregularity, thereby implement also complicatedly, and realize the cost height.
As seen, in the prior art, can't effectively calculate reactive power, or realize that cost height and difficulty are big.
Summary of the invention
In view of this, a fundamental purpose of the present invention is, a kind of reactive power calculating circuit is provided, and can calculate reactive power under the prerequisite of lower cost, and has reduced the realization difficulty.
Another fundamental purpose of the present invention is, another kind of reactive power calculating method is provided, and can calculate reactive power under the prerequisite of lower cost, and has reduced the realization difficulty.
According to an above-mentioned fundamental purpose, the invention provides a kind of reactive power calculating circuit, comprising: be used for current analog signal be converted to current digital signal road AD conversion unit, be used for voltage analog signal is converted to one tunnel AD conversion unit and the multiplier of voltage digital signal;
Further comprise between any one tunnel and the described multiplier in the described two-way AD conversion unit: phase-shifting unit, Fourier transform is carried out in output to this road AD conversion unit, after the length that Fourier transform is obtained represents that amplitude and angle are represented deflection vector 90 degree of phase place, obtain the vector that length is constant, angular deflection 90 is spent, vector constant to length then, angular deflection 90 degree carries out inverse fourier transform and output;
Also comprise between described another road AD conversion unit and the described multiplier: phase compensation unit, according to default phase compensation amount, phase compensation is carried out in output to described another road AD conversion unit, eliminate the output of this road AD conversion unit and the phase deviation between the output of described phase-shifting unit, and export to described multiplier; Wherein, described phase compensation amount is to obtain the spent time span of its output according to described phase-shifting unit to set;
Output after described multiplier is spent the phase shift 90 of described phase-shifting unit and another road AD conversion unit not output of phase shift are carried out multiplying, and with the product output that obtains, obtain reactive power.
This circuit further comprises the energy accumulation unit, and the described product that described multiplier is exported adds up.
Described phase-shifting unit comprises: Fourier transform subelement, phase tranformation subelement and inverse fourier transform subelement, wherein,
Described Fourier transform subelement carries out Fourier transform to the output of any one tunnel in the described two-way AD conversion unit, obtains length and represents that amplitude and angle represent the vector of phase place;
Described phase tranformation subelement, the length that Fourier transform is obtained represent that amplitude and angle represent deflection vector 90 degree of phase place, obtain that length is constant, the vector of angular deflection 90 degree;
Described inverse fourier transform subelement, vector length is constant, angular deflection 90 degree carries out inverse fourier transform and output.
According to another above-mentioned fundamental purpose, the invention provides a kind of reactive power calculating method, comprising: the current analog signal conversion of input is output as one road current digital signal; The voltage analog signal conversion of input is output as one road voltage digital signal;
Further comprising the steps of:
Fourier transform is carried out in any one tunnel output in the two-way output, obtain length and represent that amplitude and angle represent the vector of phase place, after the length that Fourier transform is obtained represents that amplitude and angle are represented deflection vector 90 degree of phase place, obtain the vector that length is constant, angular deflection 90 is spent, vector constant to length then, angular deflection 90 degree carries out inverse fourier transform;
To the compensation of the output phase on described another road, eliminate the phase deviation between the output behind this road output and the inverse fourier transform; Wherein, described phase compensation amount is to set according to the spent time span of output after obtaining described inverse fourier transform;
With the output of phase shift behind the inverse fourier transform 90 degree and another road not the output of phase shift carry out multiplying, obtain reactive power.
Described output phase to described another road is compensated for as: according to the phase shift processing procedure shared synchronizing cycle correspondence the synchronizing signal number, the default unit of phase departure of selecting equal amount is as phase compensation amount.
Described with after output behind the inverse fourier transform and output the carrying out multiplying of another road, this method further comprises: described product is added up.
As seen from the above technical solution, the present invention carries out Fourier transform with current digital signal or voltage digital signal earlier, and frequency-region signal phase shift 90 degree that Fourier transform is obtained, again the frequency-region signal after the phase shift is carried out inverse fourier transform, thereby can calculate reactive power according to the voltage digital signal or the current digital signal of the current digital signal after the phase shift or voltage digital signal and not phase shift.And, to the curtage signal of first-harmonic and harmonic wave, can realize that all the frequency-region signal behind its Fourier transform is carried out phase shift to be handled, thereby the present invention has improved the range of application that reactive power is calculated than the existing sampled point method of moving; Fourier transform and contravariant are changed to ripe digital processing technology, thereby are easy to realize, and cost is low, thereby the present invention has reduced the realization cost and realized difficulty than existing Hilbert filter method.
The present invention is based on existing ic for energy metering and realize the calculating of reactive power, thereby improve the reusability of hardware, and then make that technical scheme of the present invention is easy to promote.
The present invention can also carry out phase compensation to the voltage digital signal or the current digital signal of not phase shift, with voltage digital or the current digital signal after current digital signal and the phase shift processing or the phase deviation of voltage digital signal of eliminating not phase shift, thus the accuracy that has improved the reactive power that calculates.
Description of drawings
Fig. 1 is the structural representation of ic for energy metering in the prior art.
Fig. 2 is the structural drawing of reactive power calculating circuit in the embodiment of the invention.
Fig. 3 is the process flow diagram of reactive power calculating method in the embodiment of the invention.
Embodiment
For making purpose of the present invention, technical scheme and advantage clearer, below with reference to the accompanying drawing embodiment that develops simultaneously, the present invention is described in more detail.
In the embodiment of the invention, earlier current digital signal or voltage digital signal are carried out Fourier transform, and the frequency-region signal that Fourier transform obtains turn 90 degrees partially, again the frequency-region signal after the phase shift is carried out inverse fourier transform, thereby can calculate reactive power according to the voltage digital signal or the current digital signal of the current digital signal after the phase shift or voltage digital signal and not phase shift.
For first-harmonic and harmonic signal, all can obtain frequency-region signal by Fourier transform.If first-harmonic, the frequency-region signal that then obtains comprises the amplitude and the phase place of first-harmonic; If harmonic waves such as first harmonic or second harmonics, the frequency-region signal that then obtains comprises the amplitude and the phase place of signal on each secondary frequencies.Specifically, the frequency-region signal that obtains is that a length represents that amplitude and angle represent the vector of phase place.
And then this vector is done 90 degree rotate, obtain the vector that another length is constant, angular deflection 90 is spent.Last vector constant to length again, angular deflection 90 degree is done inverse-Fourier transform, gets back to time domain, has promptly realized the phase shift processing to 90 degree of current digital signal or voltage digital signal.
Wherein, for harmonic signal, the deflection of the vector of each secondary frequencies is separate.
Fig. 2 is the structural representation of reactive power calculating circuit in the embodiment of the invention.As shown in Figure 2, the reactive power calculating circuit in the present embodiment comprises: AD conversion unit 101, AD conversion unit 102 multipliers 103 and phase-shifting unit 210.
Phase-shifting unit 210, the voltage digital signal that AD conversion unit 102 is converted to carries out Fourier transform, carries out inverse fourier transform after the frequency-region signal that Fourier transform is obtained turn 90 degrees partially, obtains the voltage digital signal of phase shift 90 degree;
Based on foregoing circuit, can realize all that to the curtage signal of first-harmonic and harmonic wave the frequency-region signal behind the Fourier transform is carried out phase shift to be handled, thereby improve the range of application that reactive power is calculated than the existing sampled point method of moving; Fourier transform and contravariant are changed to ripe digital processing technology, thereby are easy to realize, and cost is low, thereby than existing Hilbert filter method, have reduced the realization cost and realized difficulty.
And above-mentioned reactive power calculating circuit can realize based on existing ic for energy metering, thereby improved the reusability of hardware, and then makes the technical scheme in the present embodiment be easy to promote.
In the present embodiment, phase-shifting unit 210 also can carry out Fourier transform to the current digital signal that AD conversion unit 101 is converted to, carry out inverse fourier transform behind frequency-region signal phase shift 90 degree that Fourier transform is obtained, obtain the current digital signal of phase shift 90 degree.
At this moment, the product of the current digital signal of phase shift 90 degree of voltage digital signal that 103 calculating of multiplier AD conversion unit 102 is converted to and phase-shifting unit 210 outputs can access reactive power equally.
Specifically, the phase-shifting unit 210 in the present embodiment can comprise: Fourier transform subelement 211, phase tranformation subelement 212 and inverse fourier transform subelement 213, wherein,
Fourier transform subelement 211, the voltage digital signal that current digital signal that AD conversion unit 101 is converted to or AD conversion unit 102 are converted to carries out Fourier transform;
Inverse fourier transform subelement 213 carries out inverse fourier transform with the frequency-region signal behind phase shift 90 degree, the current digital signal or the voltage digital signal of phase shift 90 degree that obtain.
In the practical application, no matter phase-shifting unit 210 is that current digital signal is carried out that phase shift is handled or voltage digital signal carried out phase shift handle, all may there be the possibility of generation phase deviation between another way word signal of a way word signal and not phase shift after the phase shift.
Therefore,, guarantee the accuracy of reactive power, in the reactive power calculating circuit in the present embodiment, can also comprise phase compensation unit 220 for fear of under the situation that produces phase deviation.
As shown in Figure 2, phase compensation unit 220 is according to default phase compensation amount, current digital signal to AD conversion unit 101 outputs carries out phase compensation, the phase deviation between the voltage digital signal of elimination current digital signal and phase shift 90 degree, and export to described multiplier 103.
In like manner, if carrying out phase shift, handle 210 pairs of current digital signals of phase-shifting unit, then phase compensation unit 220 promptly carries out phase compensation to the voltage digital signal of not phase shift, thereby has realized the not phase compensation of another way word signal of phase shift has further been guaranteed the accuracy of reactive power.
Wherein, phase compensation amount is to set according to the spent time span of a way word signal that phase-shifting unit 210 obtains phase shift 90 degree.
Specifically, in the above-mentioned reactive power calculating circuit, each functional unit is all controlled by same synchronizing signal.Therefore, phase shift processing procedure for phase-shifting unit 210, usually will additionally take certain synchronizing cycle, and for another way word signal of phase shift not, promptly be the compensation of the pairing phase deviation of time span that the phase shift processing procedure is additionally taken to its phase compensation amount that carries out.
For example, the phase shift processing procedure whenever takies a synchronizing cycle, then promptly can produce a unit of phase departure between the two ways of digital signals, therefore, phase compensation unit 220 can according to the phase shift processing procedure shared synchronizing cycle correspondence the synchronizing signal number, the unit of phase departure of selecting equal amount is as phase compensation amount.
Shared quantity synchronizing cycle of phase shift processing procedure is many more, and the time that the phase shift processing procedure takies is long more; And the frequency of synchronizing signal is high more, and the time that the phase shift processing procedure takies is short more.
Wherein, influence the phase shift processing procedure shared synchronizing cycle quantity material elements generally include: the factors such as hardware performance of counting, realize Fourier transform and inverse transformation of Fourier transform and inverse transformation.For example, counting of Fourier transform and inverse transformation is high more, and it is many more that required quantity synchronizing cycle is handled in phase shift.
If desired reactive power is measured to obtain the accumulation result of quadergy, can also comprise an energy accumulation unit in the foregoing circuit in the present embodiment, be used for the reactive power of multiplier 103 outputs is added up.
In the practical application, phase-shifting unit 210 can be realized with field programmable logic array (FPLA) (FPGA) or digital signal processor (DSP), at this moment, Fourier transform subelement 211, phase tranformation subelement 212 and inverse fourier transform subelement 213 can be used as the logical block of FPGA or DSP inside, also can realize by a FPGA or DSP respectively; Phase compensation unit 220 can wait with FPGA or buffer memory and realize; Can also comprise a low-pass filter in the foregoing circuit, the reactive power of multiplier 103 outputs is carried out low-pass filtering, by low-pass filter filtered reactive power be exported to the energy accumulation unit again.
It more than is detailed description to reactive power calculating circuit in the present embodiment.Below, again the reactive power calculating method in the present embodiment is elaborated.
Fig. 3 is the process flow diagram of reactive power calculating method in the embodiment of the invention.As shown in Figure 3, the reactive power calculating method in the present embodiment may further comprise the steps:
Step 301 is output as one road current digital signal with the current analog signal conversion of importing, and the voltage analog signal conversion of importing is output as one road voltage digital signal.
In this step, the frequency-region signal that Fourier transform obtains can be expressed as: length and a vector of representing the angle of phase place of comprising the expression amplitude.
In this step, the vector that step 302 obtains is done 90 degree rotations, obtain the vector that another length is constant, angular deflection 90 is spent.
Step 304 is carried out inverse fourier transform with the frequency-region signal behind phase shift 90 degree.
In this step, can obtain the current digital signal or the voltage digital signal of phase shift 90 degree behind the inverse fourier transform.
Step 305 is carried out multiplying with output behind the inverse fourier transform and the output of another road, promptly calculates the voltage digital signal or the current digital signal of not phase shift, with the current digital signal of phase shift 90 degree or the product of voltage digital signal.
Before this step, can also be according to the phase compensation amount that sets in advance, phase compensation is carried out in the output on another road of phase shift not, thereby eliminate the phase deviation between the output behind this road output and the inverse fourier transform, if promptly step 302～step 304 is that current digital signal is carried out Fourier transform, phase shift, inverse fourier transform successively, then before step 305, voltage digital signal is carried out phase compensation.
The process of phase compensation can for: according to the phase shift processing procedure shared synchronizing cycle correspondence the synchronizing signal number, the default unit of phase departure of selecting equal amount is as phase compensation amount.
So far, this flow process finishes.
In the above-mentioned flow process, current digital signal and voltage digital signal can be based on the digital signal of first-harmonic, also can be based on the digital signal of harmonic wave.
As seen, the reactive power calculating method in the present embodiment has improved the range of application that reactive power is calculated than the existing sampled point method of moving; Fourier transform and contravariant are changed to ripe digital processing technology, thereby are easy to realize, and cost is low, thereby the wattless power meter in the present embodiment has reduced the realization cost and realized difficulty than existing Hilbert filter method.
The above is preferred embodiment of the present invention only, is not to be used to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of being done, be equal to and replace and improvement etc., all should be included within protection scope of the present invention.
Claims (6)
1. reactive power calculating circuit, comprise: be used for current analog signal be converted to current digital signal road AD conversion unit, be used for voltage analog signal is converted to one tunnel AD conversion unit and the multiplier of voltage digital signal, it is characterized in that;
Further comprise between any one tunnel and the described multiplier in the described two-way AD conversion unit: phase-shifting unit, Fourier transform is carried out in output to this road AD conversion unit, after the length that Fourier transform is obtained represents that amplitude and angle are represented deflection vector 90 degree of phase place, obtain the vector that length is constant, angular deflection 90 is spent, vector constant to length then, angular deflection 90 degree carries out inverse fourier transform and output;
Also comprise between described another road AD conversion unit and the described multiplier: phase compensation unit, according to default phase compensation amount, phase compensation is carried out in output to described another road AD conversion unit, eliminate the output of this road AD conversion unit and the phase deviation between the output of described phase-shifting unit, and export to described multiplier; Wherein, described phase compensation amount is to obtain the spent time span of its output according to described phase-shifting unit to set;
The output of described multiplier after with phase shift 90 degree of described phase-shifting unit, with another road AD conversion unit not the output of phase shift carry out multiplying, and, obtain reactive power with the product output that obtains.
2. circuit as claimed in claim 1 is characterized in that this circuit further comprises the energy accumulation unit, and the described product that described multiplier is exported adds up.
3. circuit as claimed in claim 1 or 2 is characterized in that, described phase-shifting unit comprises: Fourier transform subelement, phase tranformation subelement and inverse fourier transform subelement, wherein,
Described Fourier transform subelement carries out Fourier transform to the output of any one tunnel in the described two-way AD conversion unit, obtains length and represents that amplitude and angle represent the vector of phase place;
Described phase tranformation subelement, the length that Fourier transform is obtained represent that amplitude and angle represent deflection vector 90 degree of phase place, obtain that length is constant, the vector of angular deflection 90 degree;
Described inverse fourier transform subelement, vector length is constant, angular deflection 90 degree carries out inverse fourier transform and output.
4. a reactive power calculating method comprises: the current analog signal conversion of input is output as one road current digital signal; The voltage analog signal conversion of input is output as one road voltage digital signal; It is characterized in that, further comprising the steps of:
Fourier transform is carried out in any one tunnel output in the two-way output, obtain length and represent that amplitude and angle represent the vector of phase place, after the length that Fourier transform is obtained represents that amplitude and angle are represented deflection vector 90 degree of phase place, obtain the vector that length is constant, angular deflection 90 is spent, vector constant to length then, angular deflection 90 degree carries out inverse fourier transform;
To the compensation of the output phase on described another road, eliminate the phase deviation between the output behind this road output and the inverse fourier transform; Wherein, described phase compensation amount is to set according to the spent time span of output after obtaining described inverse fourier transform;
With the output of phase shift behind the inverse fourier transform 90 degree and another road not the output of phase shift carry out multiplying, obtain reactive power.
5. method as claimed in claim 4, it is characterized in that, described output phase to described another road is compensated for as: according to the phase shift processing procedure shared synchronizing cycle correspondence the synchronizing signal number, the default unit of phase departure of selecting equal amount is as phase compensation amount.
6. as claim 4 or 5 described methods, it is characterized in that described with after output behind the inverse fourier transform and output the carrying out multiplying of another road, this method further comprises: described product is added up.
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| CN2007101188395A CN101063695B (en) | 2007-06-12 | 2007-06-12 | Reactive power calculating circuit and method |
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| CN102495250A (en) * | 2011-12-26 | 2012-06-13 | 江苏省电力试验研究院有限公司 | Quasi-synchronous wideband reactive energy meter based on Hilbert algorithm and sampling method thereof |
| CN103076493B (en) * | 2012-12-28 | 2015-04-01 | 上海贝岭股份有限公司 | Three-phase reactive power measuring and crosstalk compensating method for electric energy metering chip |
| CN106033098A (en) * | 2015-03-19 | 2016-10-19 | 上海机电工程研究所 | AC power measuring method and device based on data collection |
| CN105203837B (en) * | 2015-09-23 | 2017-12-01 | 威胜集团有限公司 | Reactive power measuring method |
| CN105929224A (en) * | 2016-04-19 | 2016-09-07 | 深圳深宝电器仪表有限公司 | Method and system for obtaining power effectiveness value |
| CN109298234B (en) * | 2017-07-25 | 2020-11-27 | 新疆金风科技股份有限公司 | Reactive power detection device and method |
| CN110727681B (en) * | 2019-09-27 | 2022-07-08 | 北京智道合创科技有限公司 | Data storage method and device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1266190A (en) * | 1999-03-05 | 2000-09-13 | 株式会社东芝 | Power arithmetic system |
| US6377037B1 (en) * | 1996-08-01 | 2002-04-23 | Siemens Power Transmission And Distribution, Inc. | Watt-hour meter with digital per-phase power factor compensation |
| CN2703260Y (en) * | 2003-12-31 | 2005-06-01 | 上海贝岭股份有限公司 | Wattless power measuring circuit for realizing 90 degree phase shifting |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6377037B1 (en) * | 1996-08-01 | 2002-04-23 | Siemens Power Transmission And Distribution, Inc. | Watt-hour meter with digital per-phase power factor compensation |
| CN1266190A (en) * | 1999-03-05 | 2000-09-13 | 株式会社东芝 | Power arithmetic system |
| CN2703260Y (en) * | 2003-12-31 | 2005-06-01 | 上海贝岭股份有限公司 | Wattless power measuring circuit for realizing 90 degree phase shifting |
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