CN103547328A - Harmonic detection method and relevant device - Google Patents

Harmonic detection method and relevant device Download PDF

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CN103547328A
CN103547328A CN201280003068.4A CN201280003068A CN103547328A CN 103547328 A CN103547328 A CN 103547328A CN 201280003068 A CN201280003068 A CN 201280003068A CN 103547328 A CN103547328 A CN 103547328A
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sequence
complex numbers
harmonic
actual situation
rfft
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CN103547328B (en
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刘海威
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Shenzhen Invt Electric Co Ltd
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Shenzhen Invt Electric Co Ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
    • G01R19/2513—Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging

Abstract

The invention discloses a harmonic detection method and a relevant device. A harmonic detection method comprises: sampling an electrical signal from a power line to obtain an N-point electrical signal sequence; performing N-point real fast Fourier transform (RFFT) computation on the N-point electrical signal sequence to obtain a first complex sequence; performing harmonic extraction processing on the first complex sequence to obtain a second complex sequence; performing virtual-real combination processing on the second complex sequence to obtain a third complex sequence; performing RFFT computation on the third complex sequence to obtain a fourth complex sequence; and performing virtual-real combination processing on the fourth complex sequence to obtain an N-point harmonic sequence. The harmonic detection method and relevant device are favourable to taking both storage space and computation time into account during harmonic detection.

Description

Harmonic detecting method and relevant apparatus
Technical field
The present invention relates to electronic technology field, be specifically related to harmonic detecting method and relevant apparatus.
Background technology
At present, in power system, the various power electronic equipments of extensive use and nonlinear load, make to have produced a large amount of harmonic waves.Harmonic wave not only can constitute a threat to the safe operation of power system itself, brings great impact and harm also may to electric circumstance around.
Active Power Filter-APF (APF, Active Power Filter) is a kind of for dynamically suppressing the power electronic equipment of harmonic wave and compensating reactive power.Static reacance generator (SVG, Static Var Generator) is one of main device in flexible AC transmitting system (FACTS, Flexible AC Transmission System).Humorous the idle of variation that involve that APF can change big or small and frequency compensates, and APF is the key that guarantees its compensation performance to the detection of harmonic signal.SVG is can dynamic compensation idle, also can compensation harmonic, and SVG is representing the developing direction that power system reactive power compensation technology is new, the detection of same harmonic signal is the key that guarantees SVG harmonic compensation performance.
Harmonic signal in power system typically refers to current harmonics and voltage harmonic.Wherein, when APF/SVG adopts parallel way to dispose, conventionally detect and administer current harmonics; When APF/SVG adopts series system to dispose, conventionally detect and administer voltage harmonic.Existing harmonic detecting technique is difficult to take into account memory space and computing time etc.
Summary of the invention
The embodiment of the present invention provides a kind of harmonic detecting method and relevant apparatus, to harmonic wave, detects and can take into account memory space and computing time.
The embodiment of the present invention provides a kind of harmonic detecting method on the one hand, comprising: the electrical signal sequence that the signal of telecommunication of sampling from power circuit is ordered to obtain N; The electrical signal sequence that described N is ordered carries out the real number FFT RFFT computing that N orders and obtains the first sequence of complex numbers; Described the first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers; Described the second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers; Described the 3rd sequence of complex numbers is carried out to real number FFT RFFT computing and obtain the 4th sequence of complex numbers; And described the 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence.
Optionally, the described signal of telecommunication of sampling from power circuit comprises with the step of the electrical signal sequence that obtains N and order: at a signal in the primitive period, and the electrical signal sequence that the equally spaced sampling signal of telecommunication is ordered to obtain N from power circuit.
Optionally, describedly described the first sequence of complex numbers is carried out to the step that harmonic wave extraction process obtains the second sequence of complex numbers comprise: remove fundametal compoment in described the first sequence of complex numbers to obtain described the second sequence of complex numbers;
Or,
It is zero to obtain the 5th sequence of complex numbers making the harmonic component in described the first sequence of complex numbers, then with described the first sequence of complex numbers, deducts described the 5th sequence of complex numbers to obtain described the second sequence of complex numbers again.
Optionally, describedly described the second sequence of complex numbers is carried out to actual situation in conjunction with the step of processing, comprise: in comprising described second sequence of complex numbers of a plurality of the second plural numbers, except DC component and nyquist frequency are put each second plural number corresponding data, processing mode by actual situation combination generates three plural number corresponding with described each the second plural number, wherein, described the 3rd real equals imaginary part coefficient and the real part sum of corresponding the second plural number, and the imaginary part coefficient of described the 3rd plural number equals the poor of corresponding the second real and imaginary part coefficient.
Optionally, describedly described the 4th sequence of complex numbers is carried out to actual situation in conjunction with the step of processing, comprise: in comprising described the 4th sequence of complex numbers of a plurality of the 4th plural numbers, except DC component and nyquist frequency are put each the 4th plural number corresponding data, processing mode by actual situation combination generates six plural number corresponding with described each the 4th plural number, wherein, described the 6th real equals imaginary part coefficient and the real part sum of corresponding the 4th plural number, and the imaginary part coefficient of described the 6th plural number equals the poor of corresponding the 4th real and imaginary part coefficient.
Optionally, the described electrical signal sequence that described N is ordered carries out the step that real number FFT RFFT computing that N orders obtains the first sequence of complex numbers and comprises: the electrical signal sequence that described N is ordered is divided by after described N, then carries out the RFFT computing that N orders and obtain the first sequence of complex numbers;
Or,
Describedly described the first sequence of complex numbers is carried out to the step that harmonic wave extraction process obtains the second sequence of complex numbers comprise: obtain the second sequence of complex numbers described the first sequence of complex numbers is carried out to harmonic wave extraction process after divided by described N again;
Or,
Describedly described the second sequence of complex numbers carried out to actual situation in conjunction with processing, to obtain the step of the 3rd sequence of complex numbers, comprise: to described the second sequence of complex numbers divided by described N after, then carry out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers;
Or, describedly described the 3rd sequence of complex numbers carried out to the step that RFFT computing obtains the 4th sequence of complex numbers comprise: obtain the 4th sequence of complex numbers described the 3rd sequence of complex numbers is carried out to RFFT computing after divided by described N again;
Or,
Describedly described the 4th sequence of complex numbers carried out to actual situation in conjunction with processing, to obtain the step of N point harmonic sequence, comprise: by described the 4th sequence of complex numbers divided by described N after, then carry out actual situation in conjunction with processing to obtain N point harmonic sequence;
Or,
Described harmonic detecting method also comprises: by the described N point harmonic sequence obtaining divided by described N.
The embodiment of the present invention also provides a kind of harmonic measurement device on the other hand, can comprise: sampling unit, the electrical signal sequence of ordering to obtain N for the signal of telecommunication of sampling from power circuit; The one RFFT arithmetic element, the electrical signal sequence of ordering for the N that described sampling unit is obtained carries out the real number FFT RFFT computing that N orders and obtains the first sequence of complex numbers; Harmonic extraction unit, carries out harmonic wave extraction process for the first sequence of complex numbers that a described RFFT arithmetic element is obtained and obtains the second sequence of complex numbers; Actual situation, in conjunction with processing unit, is carried out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers for the second sequence of complex numbers that described harmonic extraction unit is obtained; The 2nd RFFT arithmetic element, carries out RFFT computing for the 3rd sequence of complex numbers that described actual situation is obtained in conjunction with processing unit and obtains the 4th sequence of complex numbers; And described actual situation is also carried out actual situation in conjunction with processing to obtain N point harmonic sequence for, the 4th sequence of complex numbers that described the 2nd RFFT arithmetic element is obtained in conjunction with processing unit.
Optionally, described actual situation in conjunction with processing unit specifically for, in described the second sequence of complex numbers that comprises a plurality of the second plural numbers obtaining in described harmonic extraction unit, except DC component and nyquist frequency are put each second plural number corresponding data, processing mode by actual situation combination generates three plural number corresponding with described each the second plural number, wherein, described the 3rd real equals imaginary part coefficient and the real part sum of corresponding the second plural number, the imaginary part coefficient of described the 3rd plural number equals the poor of corresponding the second real and imaginary part coefficient, to obtain comprising the 3rd sequence of complex numbers of a plurality of the 3rd plural numbers.
Optionally, described actual situation in conjunction with processing unit also specifically for, in the 4th sequence of complex numbers that comprises a plurality of the 4th plural numbers obtaining in described the 2nd RFFT arithmetic element, except DC component and nyquist frequency are put each the 4th plural number corresponding data, processing mode by actual situation combination generates six plural number corresponding with described each the 4th plural number, wherein, described the 6th real equals imaginary part coefficient and the real part sum of corresponding the 4th plural number, the imaginary part coefficient of described the 6th plural number equals the poor of corresponding the 4th real and imaginary part coefficient, to obtain comprising the N point harmonic sequence of a plurality of the 6th plural numbers.
Optionally, a described RFFT arithmetic element, then is carried out the RFFT computing that N orders and is obtained the first sequence of complex numbers divided by after described N specifically for, the electrical signal sequence that the N that described sampling unit is obtained is ordered;
Or,
Described harmonic extraction unit specifically for, a described RFFT arithmetic element is carried out to described the first sequence of complex numbers that RFFT computing obtains divided by after described N, then carries out harmonic wave extraction process and obtain the second sequence of complex numbers;
Or,
Described actual situation in conjunction with processing unit specifically for, described the second sequence of complex numbers that described harmonic extraction unit is obtained divided by after described N, then carry out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers;
Or,
Described the 2nd RFFT arithmetic element, then is carried out RFFT computing and is obtained the 4th sequence of complex numbers divided by after described N specifically for, the 3rd sequence of complex numbers that described actual situation is obtained in conjunction with processing unit;
Or,
Described actual situation in conjunction with processing unit also for, described the 4th sequence of complex numbers that described the 2nd RFFT arithmetic element is obtained divided by after described N, then carry out actual situation in conjunction with processing to obtain N point harmonic sequence;
Or,
Described actual situation is also carried out actual situation in conjunction with processing to obtain N point harmonic sequence for, described the 4th sequence of complex numbers that described the 2nd RFFT arithmetic element is obtained in conjunction with processing unit, and described N point harmonic sequence is exported afterwards divided by described N.
The another aspect of the embodiment of the present invention also provides a kind of harmonic wave abatement apparatus, comprising:
Harmonic measurement device, the electrical signal sequence of ordering to obtain N for the signal of telecommunication of sampling from power circuit; The electrical signal sequence that described N is ordered carries out the real number FFT RFFT computing that N orders and obtains the first sequence of complex numbers; Described the first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers; Described the second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers; Described the 3rd sequence of complex numbers is carried out to RFFT computing and obtain the 4th sequence of complex numbers; And described the 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence output;
Signal of telecommunication feedback device, generates the compensation signal of telecommunication for the described N point harmonic sequence based on described harmonic measurement device output, and the described compensation signal of telecommunication generating is fed back to described power circuit to eliminate the harmonic wave producing in described power circuit.
The embodiment of the present invention also provides a kind of computer-readable storage medium on the other hand, and described computer-readable storage medium has program stored therein, and described program comprises the part or all of step as above-mentioned embodiment of the method while carrying out.
Therefore in the technical scheme that the embodiment of the present invention provides, the signal of telecommunication of sampling from power circuit carries out with the electrical signal sequence that obtains N and order the RFFT computing that N orders and obtains the first sequence of complex numbers; The first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers; The second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers; The 3rd sequence of complex numbers is carried out to RFFT computing and obtain the 4th sequence of complex numbers; The 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence.The technical program is without carry out conjugate operation before and after RFFT, also without data, extract operation, and only need carry out twice actual situation in conjunction with processing operation, simply add reducing, so in terms of existing technologies, comparatively save computing time, and carry out computing owing to can making full use of RFFT code, so also can save code space.
Further, do not need to increase additional storage space, can code space, number of memory cells and computing time complex optimum.
Accompanying drawing explanation
In order to be illustrated more clearly in the technical scheme of the embodiment of the present invention, below the accompanying drawing of embodiment being described to required use is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.
Fig. 1 is the schematic flow sheet of a kind of harmonic detecting method of providing of the embodiment of the present invention;
Fig. 2 is the storage schematic diagram of the calculated data that provides of the embodiment of the present invention;
Fig. 3 is the schematic diagram of a kind of harmonic measurement device of providing of the embodiment of the present invention;
Fig. 4 is the schematic diagram of a kind of harmonic wave abatement apparatus of providing of the embodiment of the present invention;
Fig. 5 a is that a kind of that the embodiment of the present invention provides is applied to the configuration diagram in electrical network by harmonic wave abatement apparatus;
Fig. 5 b be the embodiment of the present invention provide another harmonic wave abatement apparatus is applied to the configuration diagram in electrical network;
Fig. 5 c is that the another kind that the embodiment of the present invention provides is applied to the configuration diagram in electrical network by harmonic wave abatement apparatus.
The specific embodiment
The embodiment of the present invention provides a kind of harmonic detecting method and relevant apparatus, to harmonic wave, detects and can take into account memory space and computing time.
Below by specific embodiment, be described in detail respectively.
For making goal of the invention of the present invention, feature, advantage can be more obvious and understandable, below in conjunction with the accompanying drawing in the embodiment of the present invention, technical scheme in the embodiment of the present invention is clearly and completely described, obviously, the embodiments described below are only the present invention's part embodiment, but not whole embodiment.Embodiment based in the present invention, those of ordinary skills, not making all other embodiment that obtain under creative work prerequisite, belong to the scope of protection of the invention.
Term " first " in description of the present invention and claims and above-mentioned accompanying drawing, " second ", " the 3rd " " 4th " etc. (if existence) are for distinguishing similar object, and needn't be for describing specific order or precedence.The data that should be appreciated that such use suitably can exchanged in situation, so as embodiments of the invention described herein for example can with except diagram here or describe those order enforcement.In addition, term " comprises " and " having " and their any distortion, intention is to cover not exclusive comprising, for example, those steps or unit that the process that has comprised series of steps or unit, method, system, product or equipment are not necessarily limited to clearly list, but can comprise clearly do not list or for these processes, method, product or equipment intrinsic other step or unit.
Harmonic signal detection range of the present invention comprises the detection to harmonic voltage and/or harmonic current.
Harmonic signal detection method mainly contains: analog bandpass filtering device detection method, the detection method based on instantaneous reactive power theory, FFT (FFT, Fast Fourier Transformation) detection method etc.Detection method based on simulation circulation wave filter can only detect the harmonic wave within the scope of fixed frequency, cannot carry out real-Time Compensation to the harmonic wave changing, and easily cause resonance; FFT method and the detection method based on instantaneous reactive power theory can detect the harmonic wave within the scope of broad frequency domain, therefore, in power system, are widely used.Detection method based on instantaneous reactive has original advantage idle with harmonic wave entire compensation and quick responder's mask, and FFT detection method is being carried out aspect signal spectrum labor and data demonstration, that the former is irreplaceable, especially in harmonic content analysis with carry out aspect separate compensation with the obvious advantage to indivedual frequency spectrums.Consider the duality of FFT and IFFT, those have been used to FFT detection method and carried out (as part APF and SVG) in the device of harmonic content analysis demonstration, can directly call existing code and carry out inverse transformation and obtain harmonic wave instruction, FFT is more had superiority in the application of these occasions.The denouncing of harmonic wave extracting method based on FFT is to calculate that more complicated, real-time are poor, committed memory is more while calculating.
In APF/SVG, need to one or when several specific subharmonic are compensated simultaneously, it is essential that FFT calculates, HARMONIC SIGNAL EXTRACTION FROM based on FFT inverse transformation principle, because committed memory is more, the sequential operation time is longer, is applied and is obstructed in extensive processing in real time.
Some improved Harmonic Current Detecting Methods based on FFT are analyzed as follows:
(1) adopt FFT to calculate harmonic sequence, although positive inverse transformation can share same FFT program segment, cost is to have reduced direct transform efficiency, has increased by 1 times of memory space, to inverse transformation method, also need (or sequence) operation of extra conjugation and data to extract operation.
(2) adopt real number and plural FFT in conjunction with calculating harmonic sequence, direct transform operation time and memory space can obtain optimum, although a kind of method has improved the efficiency of direct transform, these class methods have been sacrificed code and shared, and have increased the complexity of program.
(3) adopt real number FFT (RFFT, Real number FFT) to calculate harmonic sequence, though this method can code reuse, but additionally increase by 1 times of memory space, need real empty lock out operation twice, operand also increases greatly, has affected the arithmetic speed of processor.Visible above-mentioned several method respectively has pluses and minuses, there is no a kind of combination property that can take into account code reuse, memory space and computing time.
An embodiment of harmonic detecting method of the present invention, can comprise: the electrical signal sequence that the signal of telecommunication of sampling from power circuit is ordered to obtain N; The electrical signal sequence that this N is ordered carries out the real number FFT RFFT computing that N orders and obtains the first sequence of complex numbers; The first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers; The second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers; The 3rd sequence of complex numbers is carried out to RFFT computing and obtain the 4th sequence of complex numbers; The 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence.
Refer to Fig. 1, Figure 1 shows that a kind of harmonic detecting method that the embodiment of the present invention provides, can comprise following content:
The electrical signal sequence that step 101, the signal of telecommunication of sampling from power circuit are ordered to obtain N.
In some embodiments of the invention, can be at a signal in the primitive period, from power circuit uniformly-spaced or the sampling signal of telecommunication of the unequal interval electrical signal sequence of ordering to obtain N.For instance, for example can be from three-phase power circuit, extract a signal in the primitive period uniformly-spaced or the three-phase current signal of unequal interval (or three-phase voltage signal), to obtain the N point current signal sequence (or N point voltage burst) that every phase current is corresponding.
Step 102, the electrical signal sequence that N is ordered carry out the RFFT computing that N orders and obtain the first sequence of complex numbers.
Wherein, the first sequence of complex numbers comprises a plurality of the first plural numbers.
Refer to Fig. 2, Figure 2 shows that the storage schematic diagram of the calculated data that the embodiment of the present invention provides.As shown in Figure 2, the electrical signal sequence that N is ordered is expressed as R 0～R n-1, suppose with N the electrical signal sequence (R that cell stores N is ordered 0～R n-1), the electrical signal sequence (R that N is ordered 0～R n-1) carry out the RFFT computing that N orders and obtain the first sequence of complex numbers, DC component and nyquist frequency in the first sequence of complex numbers are put to corresponding data (as R 0and R n/2) be stored in 2 memory cell, also can be by wherein (the N-2)/2 plural number (R in a remaining N-2 plural number in the first sequence of complex numbers 1～R n/2-1) real part be stored in (N-2)/2 memory cell, and will be somebody's turn to do (N-2)/2 plural imaginary part coefficient storage in (N-2)/2 memory cell because in the first sequence of complex numbers except DC component and nyquist frequency are put corresponding data (as R 0and R n/2) outside two parts plural numbers (R 1～R n/2-1) and (R n/2+1～R n-1) real part and imaginary part coefficient there is conjugate symmetry, therefore utilize the plural number (R of storage 1～R n/2-1) can recover the plural number that the first sequence of complex numbers is not stored, like this can larger province memory space, certainly, also can store (the R in the first sequence of complex numbers n/2+1～R n-1) part, do not store (the R in the first sequence of complex numbers 1～R n/2-1), and according to (R n/2+1～R n-1) also can recover (R 1～R n/2-1) part.Be appreciated that the plural number in other sequence of complex numbers with conjugate symmetry also can store in this manner.
Please continue referring to Fig. 1, step 103, the first sequence of complex numbers is carried out to harmonic wave extraction process obtain the second sequence of complex numbers.
In some embodiments of the invention, the first sequence of complex numbers is carried out to the step that harmonic wave extraction process obtains the second sequence of complex numbers can be comprised: remove fundametal compoment in the first sequence of complex numbers to obtain the second sequence of complex numbers (certainly, yet can remove the harmonic component that does not need number of times,, can only extract the harmonic component that one or several sets number of times), for instance, it is zero to obtain the second sequence of complex numbers for example can making the fundametal compoment in the first sequence of complex numbers; Or it is zero to obtain the 5th sequence of complex numbers also can making the harmonic component in the first sequence of complex numbers, then deducts the 5th sequence of complex numbers to obtain the second sequence of complex numbers with the first sequence of complex numbers again.
Wherein, the second sequence of complex numbers comprises a plurality of the second plural numbers.
Step 104, the second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers.
In some embodiments of the invention, for example, in comprising the second sequence of complex numbers of a plurality of the second plural numbers, except DC component and nyquist frequency are put each second plural number corresponding data, processing mode by actual situation combination generates three plural number corresponding with described each the second plural number, and, described the 3rd real equals imaginary part coefficient and the real part sum of second plural number corresponding to it, the imaginary part coefficient of described the 3rd plural number equals the poor of second real corresponding to it and imaginary part coefficient, so, by putting each second plural number corresponding data except DC component and nyquist frequency in the second sequence of complex numbers, do actual situation as above and just can obtain in conjunction with processing the 3rd sequence of complex numbers that N is ordered, the 3rd sequence of complex numbers comprises a plurality of the 3rd plural numbers, wherein, the 3rd sequence of complex numbers that this N is ordered comprises that DC component and the nyquist frequency in the second sequence of complex numbers put corresponding data, also comprise in the second sequence of complex numbers, except DC component and nyquist frequency are put each second plural number corresponding data, by processing mode generation and described each second plural the 3rd corresponding plural number of actual situation combination.
Step 105, the 3rd sequence of complex numbers is carried out to RFFT computing obtain the 4th sequence of complex numbers.
Wherein, the 4th sequence of complex numbers comprises a plurality of the 4th plural numbers.
Step 106, the 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence.
In some embodiments of the invention, for example, in comprising the 4th sequence of complex numbers of a plurality of the 4th plural numbers, except DC component and nyquist frequency are put each the 4th plural number corresponding data, processing mode by actual situation combination generates six plural number corresponding with described each the 4th plural number, described the 6th real equals imaginary part coefficient and the real part sum of four plural number corresponding to it, the imaginary part coefficient of described the 6th plural number equals the poor of four real corresponding to it and imaginary part coefficient, so, each plural number in the 4th sequence of complex numbers is done to actual situation as above and in conjunction with processing, just can obtain the N point harmonic sequence that comprises a plurality of the 6th plural numbers, wherein, this N point harmonic sequence comprises in above-mentioned the 4th sequence of complex numbers that DC component and nyquist frequency are put corresponding data, also comprise in above-mentioned the 4th sequence of complex numbers, except DC component and nyquist frequency are put each the 4th plural number corresponding data, by processing mode generation and described each the 4th plural the 6th corresponding plural number of actual situation combination.
Wherein, twice real empty identical in conjunction with the mode of processing, can code multiplexing, and then be conducive to save code memory space.The present embodiment scheme is without carrying out conjugate operation, and only need simply add reducing to data, just can and not increase under the prerequisite of additional memory units at less operand, realize multiplexing RFFT code and complete Harmonics Calculation, and Output rusults also can not need data to extract the operations such as sequence, sequence of real numbers that completely can be corresponding initial, is conducive to save computing time, also can not increase extra code space and memory space.As need, calculate the occasions such as harmonic amplitude, phase place, total harmonic distortion (THD, total harmonic distortion), can also reduce program's memory space by abundant multiplexing code.
It should be noted that, the N in the embodiment of the present invention, refers to counting of inverse Fourier transform, i.e. the harmonic sequence length of output.
In addition, in order to obtain real amplitude, can also reduce to amplitude, through the computing of " divided by N " (can be described as in embodiments of the present invention 1/N operation).
For instance, in one embodiment of this invention, the electrical signal sequence that N is ordered in step 102 carries out RFFT computing that N orders and obtains the first sequence of complex numbers and can comprise following concrete steps: after the electrical signal sequence that N is ordered is divided by N, then carries out the RFFT computing that N orders and obtain the first sequence of complex numbers.
Or, in another embodiment of the present invention, the first sequence of complex numbers is carried out to harmonic wave extraction process obtain the second sequence of complex numbers and can comprise following concrete steps in step 103: obtain the second sequence of complex numbers the first sequence of complex numbers is carried out to harmonic wave extraction process after divided by N again.
Or, in another embodiment of the present invention, the second sequence of complex numbers carried out to actual situation can comprise following concrete steps in conjunction with processing to obtain the 3rd sequence of complex numbers in step 104: to the second sequence of complex numbers divided by N after, then carry out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers.
Or, in another embodiment of the present invention, the 3rd sequence of complex numbers is carried out to RFFT computing obtain the 4th sequence of complex numbers and can comprise following concrete steps in step 105: obtain the 4th sequence of complex numbers the 3rd sequence of complex numbers is carried out to RFFT computing after divided by N again.
Or, in another embodiment of the present invention, will carry out actual situation and comprise following concrete steps in conjunction with processing to obtain N point harmonic sequence obtaining the 4th sequence of complex numbers in step 106: to the 4th sequence of complex numbers divided by N after, then carry out actual situation in conjunction with processing to obtain N point harmonic sequence.
Or, in another embodiment of the present invention, also the N point harmonic sequence obtaining can be exported divided by after N again.
For the ease of better understanding the embodiment of the present invention, below by the method that the embodiment of the present invention is provided according to making a setting analysis.
For RFFT, the electrical signal sequence of sampling can be expressed as:
x(n)＝x R(n),0≤n≤N-1；
Because the imaginary part of sampling electrical signal sequence is 0, so can draw according to DFT definition and character:
DFT : X R ( k ) = Σ n = 0 N - 1 [ x R ( n ) cos 2 πkn N + x I ( n ) sin 2 πkn N ] = Σ n = 0 N - 1 x R ( n ) cos 2 πkn N
X I ( k ) = Σ n = 0 N - 1 [ x R ( n ) sin 2 πkn N - x I ( n ) cos 2 πkn N ] = Σ n = 0 N - 1 x R ( n ) sin 2 πkn N ;
That is, after RFFT, real part is cosine component, is real even sequence, and imaginary part is sinusoidal component, is real odd sequence.
For inverse fourier transform, list entries is:
X(k)＝X R(k)+jX I(k),0≤k≤N-1；
Its inverse transformation result is x (n), according to the character of inverse Fourier transform, can obtain:
x(n)＝IFFT(X(k))
＝IFFT(X R(k)+jX I(k))
＝IFFT(X R(k))+j*IFFT(X I(k))
＝conj(FFT(X R(k)))+j*conj(FFT(X I(k)))
＝FFT(X R(k))+j*(-1)*(FFT(X I(k))
Can obtain: x (n)=FFT (X r(k))-j* (FFT (X i(k)),
Wherein, 0≤k≤N-1;
It should be noted that, in above formula, omitted 1/N operation, consider that 1/N only affects final amplitude, so do not analyze herein, be understandable that, if need obtain real amplitude, can carry out 1/N operation to result.
By x (n)=FFT (X r(k))-j* (FFT (X i(k)) can find out, in this result, still contain two FFT conversion, and each conversion needs N data, therefore, also need this formula x (n)=FFT (X r(k))-j* (FFT (X i(k)) be further analyzed, as follows:
Make S (K)=X r(k)+X i(k), then at S (K)=X r(k)+X i(k) FFT is asked on both sides, obtains:
S(K)＝X R(k)+X I(k)；
Wherein, FFT(X r(k)) be pure real number, and FFT(X i(k)) be pure imaginary number.
Therefore, can obtain:
S=FFT (X r(k))+FFT (X i(k))=s r+ j*s i, wherein, 0≤k≤N-1;
Wherein, s=FFT (X r(k))+FFT (X i(k))=s r+ j*s i.
So, formula x (n)=FFT (X r(k))-j* (FFT (X i(k) can abbreviation be):
X (n)=s r+ s i, wherein, 0≤k≤N-1;
By formula x (n)=s r+ s iknown, only need to build S(K) and it is carried out to FFT, just can pass through formula x (n)=s r+ s ireduce initial sequence of real numbers x (n).In fact in the consistent situation of number of memory cells, need to build S(K) and formula x (n)=s r+ s iidentical expression formula, so can share a program segment.
As can be seen from Figure 2, typical N point sequence of real numbers is after RFFT conversion, can utilize its conjugate symmetry only to store the data of half (being spectrum value), so if calculate N point, also need to reduce second half data, because the Data Conjugate of second half data and preservation is symmetrical, so S(K) building mode can be decomposed into:
Figure BDA00002963495000131
Obviously, x(n) can adopt equally said method to realize, not repeat them here.
As from the foregoing, the present embodiment carries out with the electrical signal sequence that obtains N and order the RFFT computing that N orders by the signal of telecommunication of sampling from power circuit and obtains the first sequence of complex numbers; The first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers; The second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers; The 3rd sequence of complex numbers is carried out to RFFT computing and obtain the 4th sequence of complex numbers; The 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence, this programme is without carry out conjugate operation before and after RFFT, also without data, extract operation, and only need carry out twice actual situation binding operation, simply add reducing, so in terms of existing technologies, comparatively save computing time, and owing to can making full use of RFFT code, carry out computing, so also can save code space.Further, do not need to increase additional storage space, can code space, number of memory cells and computing time complex optimum.
For ease of better understanding and implementing embodiment of the present invention such scheme, be also provided for implementing the relevant apparatus of such scheme below.
Refer to Fig. 3, the embodiment of the present invention also provides a kind of harmonic measurement device 300, can comprise: sampling unit 301, a RFFT arithmetic element 302, harmonic extraction unit 303, actual situation are in conjunction with processing unit 304 and the 2nd RFFT arithmetic element 305.
Wherein, sampling unit 301, the electrical signal sequence of ordering to obtain N for the signal of telecommunication of sampling from power circuit.
In some embodiments of the invention, sampling unit 301 can be at a signal in the primitive period, from power circuit uniformly-spaced or the sampling signal of telecommunication of the unequal interval electrical signal sequence of ordering to obtain N.For example sampling unit 301 can be from three-phase power circuit, extract a signal in the primitive period uniformly-spaced or the three-phase current signal of unequal interval (or three-phase voltage signal), to obtain the N point current signal sequence (or N point voltage burst) of every phase current.
The one RFFT arithmetic element 302, the electrical signal sequence of ordering for the N that sampling unit 301 is obtained carries out the real number FFT RFFT computing that N orders and obtains the first sequence of complex numbers.Wherein, the first sequence of complex numbers comprises a plurality of the first plural numbers.
Harmonic extraction unit 303, carries out harmonic wave extraction process for the first sequence of complex numbers that a RFFT arithmetic element 302 is obtained and obtains the second sequence of complex numbers.Wherein, the second sequence of complex numbers comprises a plurality of the second plural numbers.
Actual situation, in conjunction with processing unit 304, is carried out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers for the second sequence of complex numbers that harmonic extraction unit 303 is obtained.Wherein, the 3rd sequence of complex numbers comprises a plurality of the 3rd plural numbers.
The 2nd RFFT arithmetic element 305, carries out RFFT computing for the 3rd sequence of complex numbers that actual situation is obtained in conjunction with processing unit 304 and obtains the 4th sequence of complex numbers.Wherein, the 4th sequence of complex numbers comprises a plurality of the 4th plural numbers.
Actual situation is also carried out actual situation in conjunction with processing to obtain N point harmonic sequence for the 4th sequence of complex numbers that the 2nd RFFT arithmetic element 305 is obtained in conjunction with processing unit 303.
In some embodiments of the invention, actual situation can be specifically in conjunction with processing unit 304, in the second sequence of complex numbers that comprises a plurality of the second plural numbers obtaining in harmonic extraction unit 303, except DC component and nyquist frequency are put each second plural number corresponding data, processing mode by actual situation combination generates three plural number corresponding with described each the second plural number, and, described the 3rd real equals imaginary part coefficient and the real part sum of second plural number corresponding with it, the imaginary part coefficient of described the 3rd plural number equals the poor of second real corresponding to it and imaginary part coefficient, processing by each second plural number being carried out to actual situation combination is to obtain the 3rd sequence of complex numbers.
In some embodiments of the invention, actual situation in conjunction with processing unit 304 also specifically for, in the 4th sequence of complex numbers that comprises a plurality of the 4th plural numbers obtaining for the 2nd RFFT arithmetic element 305, except DC component and nyquist frequency are put each the 4th plural number corresponding data, processing mode by actual situation combination generates six plural number corresponding with described each the 4th plural number, and, described the 6th real equals imaginary part coefficient and the real part sum of four plural number corresponding to it, the imaginary part coefficient of described the 6th plural number equals the poor of the corresponding with it the 4th multiple real and imaginary part coefficient, processing by each the 4th plural number being carried out to actual situation combination is to obtain comprising the N point harmonic sequence of a plurality of the 6th plural numbers.
Be appreciated that, the 3rd sequence of complex numbers that actual situation obtains in conjunction with processing unit 304 comprises that DC component and the nyquist frequency in the second sequence of complex numbers put corresponding data, also comprise in the second sequence of complex numbers except DC component and nyquist frequency are put each second plural number corresponding data, by processing mode the 3rd plural number that generate and that described each the second plural number is corresponding of actual situation combination.The N point harmonic sequence that actual situation obtains in conjunction with processing unit 304 comprises that DC component and nyquist frequency in above-mentioned the 4th sequence of complex numbers put corresponding data, also comprise in above-mentioned the 4th sequence of complex numbers except DC component and nyquist frequency are put each the 4th plural number corresponding data, by processing mode the 6th plural number that generate and that described each the 4th plural number is corresponding of actual situation combination.
It should be noted that, the N in the embodiment of the present invention, refers to counting of inverse Fourier transform, i.e. the harmonic sequence length of output.
In addition, in order to obtain real amplitude, can also reduce to amplitude, through the computing of " divided by N " (can be described as in embodiments of the present invention 1/N operation).
In some embodiments of the invention, harmonic extraction unit 303 specifically for, remove fundametal compoment in the first sequence of complex numbers to obtain the second sequence of complex numbers.
In some embodiments of the invention, a RFFT arithmetic element 302 can be specifically for, and the electrical signal sequence that the N that sampling unit 301 is obtained is ordered is divided by after N, then carry out the RFFT computing that N orders and obtain the first sequence of complex numbers.
Or,
Harmonic extraction unit 303 can be specifically for, and a RFFT arithmetic element 302 is carried out to the first sequence of complex numbers that RFFT computing obtains divided by after N, then carry out harmonic wave extraction process and obtain the second sequence of complex numbers.
Or,
Actual situation in conjunction with processing unit 304 specifically for, the second sequence of complex numbers that harmonic extraction unit 303 is obtained divided by after N, then carry out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers.
Or,
The 2nd RFFT arithmetic element 305, then is carried out RFFT computing and is obtained the 4th sequence of complex numbers divided by after N specifically for, the 3rd sequence of complex numbers that actual situation is obtained in conjunction with processing unit 304.
Or,
Actual situation in conjunction with processing unit 304 also for, the 4th sequence of complex numbers that the 2nd RFFT arithmetic element 305 is obtained divided by after N, then carry out actual situation in conjunction with processing to obtain N point harmonic sequence.
Or,
Actual situation is also carried out actual situation in conjunction with processing to obtain N point harmonic sequence for, the 4th sequence of complex numbers that the 2nd RFFT arithmetic element 305 is obtained in conjunction with processing unit 304, and this N point harmonic sequence is exported afterwards divided by N.
The function of each functional module that is appreciated that the harmonic measurement device 300 of the present embodiment can be according to the method specific implementation in said method embodiment, and its specific implementation process can, referring to the associated description in said method embodiment, repeat no more herein.The present embodiment harmonic measurement device 300 can be deployed in APF/SVG, usings as carrying out the device of harmonic wave detection in APF/SVG.
Refer to Fig. 4, the embodiment of the present invention also provides a kind of harmonic wave abatement apparatus 400, can comprise: harmonic measurement device 410 and signal of telecommunication feedback device 420.
Wherein, harmonic measurement device 410, the electrical signal sequence of ordering to obtain N for the signal of telecommunication of sampling from power circuit; The electrical signal sequence that this N is ordered carries out the RFFT computing that N orders and obtains the first sequence of complex numbers; The first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers; The second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers; The 3rd sequence of complex numbers is carried out to RFFT computing and obtain the 4th sequence of complex numbers; The 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence output.
Signal of telecommunication feedback device 420, generates the compensation signal of telecommunication for the N point harmonic sequence based on harmonic measurement device 410 outputs, and this compensation signal of telecommunication generating is fed back to this power circuit to eliminate the harmonic wave producing in this power circuit.
In some embodiments of the invention, harmonic measurement device 410 can be at a signal in the primitive period, from power circuit uniformly-spaced or the sampling signal of telecommunication of the unequal interval electrical signal sequence of ordering to obtain N.For instance, harmonic measurement device 410 for example can be from three-phase power circuit, extract a signal in the primitive period uniformly-spaced or the three-phase current signal of unequal interval (or three-phase voltage signal), to obtain the N point current signal sequence (or N point voltage burst) of every phase current.
In some embodiments of the invention, harmonic measurement device 410 for example can adopt data storage method as shown in Figure 2 to carry out data storage.The electrical signal sequence that for example N is ordered is expressed as R 0～R n-1, suppose with N the electrical signal sequence (R that cell stores N is ordered 0～R n-1), the electrical signal sequence (R that N is ordered 0～R n-1) carry out the RFFT computing that N orders and obtain the first sequence of complex numbers, DC component and nyquist frequency in the first sequence of complex numbers are put to corresponding data (as R 0and R n/2) be stored in 2 memory cell, also can be by wherein (the N-2)/2 plural number (R in a remaining N-2 plural number in the first sequence of complex numbers 1～R n/2-1) real part be stored in (N-2)/2 memory cell, and will be somebody's turn to do (N-2)/2 plural imaginary part coefficient storage in (N-2)/2 memory cell because in the first sequence of complex numbers except DC component and nyquist frequency are put corresponding data (as R 0and R n/2) outside two parts plural numbers (R 1～R n/2-1) and (R n/2+1～R n-1) real part and imaginary part coefficient there is conjugate symmetry, therefore utilize the plural number (R of storage 1～R n/2-1) can recover the plural number that the first sequence of complex numbers is not stored, like this can larger province memory space, certainly, harmonic measurement device 410 also can be stored (the R in the first sequence of complex numbers n/2+1～R n-1) part, do not store (the R in the first sequence of complex numbers 1～R n/2-1), and according to (R n/2+1～R n-1) also can recover (R 1～R n/2-1) part.Be appreciated that the plural number in other sequence of complex numbers with conjugate symmetry also can store in this manner.
In some embodiments of the invention, 410 pairs of the first sequence of complex numbers of harmonic measurement device carry out harmonic wave extraction process and obtain the second sequence of complex numbers and for example can comprise: the fundametal compoment of removing in the first sequence of complex numbers (yet can be removed the harmonic component that does not need number of times certainly to obtain the second sequence of complex numbers,, can only extract the harmonic component that one or several sets number of times), for instance, it is zero to obtain the second sequence of complex numbers for example can making the fundametal compoment in the first sequence of complex numbers; Or it is zero to obtain the 5th sequence of complex numbers also can making the harmonic component in the first sequence of complex numbers, then subtracts the 5th sequence of complex numbers to obtain the second sequence of complex numbers with the first sequence of complex numbers again.Wherein, the second sequence of complex numbers comprises a plurality of the second plural numbers.
In some embodiments of the invention, 410 pairs of the second sequence of complex numbers of harmonic measurement device carry out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers, for example can comprise: in comprising the second sequence of complex numbers of a plurality of the second plural numbers, except DC component and nyquist frequency are put each second plural number corresponding data, processing mode by actual situation combination generates three plural number corresponding with described each the second plural number, and, described the 3rd real equals imaginary part coefficient and the real part sum of second plural number corresponding to it, the imaginary part coefficient of described the 3rd plural number equals the poor of second real corresponding to it and imaginary part coefficient, so, by putting each second plural number corresponding data except DC component and nyquist frequency in the second sequence of complex numbers, do actual situation as above and just can obtain in conjunction with processing the 3rd sequence of complex numbers that N is ordered, the 3rd sequence of complex numbers comprises a plurality of the 3rd plural numbers, wherein, the 3rd sequence of complex numbers that this N is ordered comprises that DC component and the nyquist frequency in the second sequence of complex numbers put corresponding data, also comprise in the second sequence of complex numbers except DC component and nyquist frequency are put each second plural number corresponding data, by processing mode generation and described each second plural the 3rd corresponding plural number of actual situation combination.
In some embodiments of the invention, harmonic measurement device 410 carries out actual situation in conjunction with processing to obtain N point harmonic sequence by the 4th sequence of complex numbers, for example can comprise for comprising in the 4th sequence of complex numbers of a plurality of the 4th plural numbers, except DC component and nyquist frequency are put each the 4th plural number corresponding data, processing mode by actual situation combination generates six plural number corresponding with described each the 4th plural number, described the 6th real equals imaginary part coefficient and the real part sum of four plural number corresponding to it, the imaginary part coefficient of described the 6th plural number equals the poor of four real corresponding to it and imaginary part coefficient, so, each plural number in the 4th sequence of complex numbers is done to actual situation as above and in conjunction with processing, just can obtain the N point harmonic sequence that comprises a plurality of the 6th plural numbers, wherein, this N point harmonic sequence comprises in above-mentioned the 4th sequence of complex numbers that DC component and nyquist frequency are put corresponding data, also comprise in above-mentioned the 4th sequence of complex numbers except DC component and nyquist frequency are put each the 4th plural number corresponding data, by processing mode generation and described each the 4th plural the 6th corresponding plural number of actual situation combination.
Wherein, twice real empty identical in conjunction with the mode of processing, can code multiplexing, and then be conducive to save code memory space.The present embodiment scheme is without carrying out conjugate operation, and only need simply add reducing to data, just can and not increase under the prerequisite of additional memory units at less operand, realize multiplexing RFFT code and complete Harmonics Calculation, and Output rusults also can not need data to extract the operations such as sequence, sequence of real numbers that completely can be corresponding initial, is conducive to save computing time, also can not increase extra code space and memory space.As need, calculate the occasions such as harmonic amplitude, phase place, total harmonic distortion (THD), can also reduce program's memory space by abundant multiplexing code.
In addition, in order to obtain real amplitude, in some embodiments of the invention, harmonic measurement device 410 can also reduce to amplitude, through the computing of " divided by N " (can be described as in embodiments of the present invention 1/N operation).
For instance, in one embodiment of this invention, harmonic measurement device 410 can be after the electrical signal sequence that N is ordered be divided by N, then carries out the RFFT computing that N orders and obtain the first sequence of complex numbers.
Or in another embodiment of the present invention, harmonic measurement device 410 can obtain the second sequence of complex numbers the first sequence of complex numbers is carried out to harmonic wave extraction process after divided by N again.
Or, in another embodiment of the present invention, harmonic measurement device 410 can to the second sequence of complex numbers divided by N after, then carry out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers.
Or in another embodiment of the present invention, harmonic measurement device 410 can obtain the 4th sequence of complex numbers the 3rd sequence of complex numbers is carried out to RFFT computing after divided by N again.
Or, in another embodiment of the present invention, harmonic measurement device 410 can to the 4th sequence of complex numbers divided by N after, then carry out actual situation in conjunction with processing to obtain N point harmonic sequence.
Or in another embodiment of the present invention, harmonic measurement device 410 can also can be exported the N point harmonic sequence obtaining divided by after N again.
Be understandable that, harmonic measurement device 410 can, as harmonic measurement device 300, can have the part or all of function of harmonic measurement device 300.Each function of harmonic measurement device 410 can be according to the method specific implementation in said method embodiment, and its specific implementation process can, referring to the associated description in said method embodiment, repeat no more herein.
In some embodiments of the invention, the harmonic measurement device 410 in harmonic wave abatement apparatus 400 and signal of telecommunication feedback device 420 for example can be deployed in each power network topology as shown in Fig. 5 a-5c, to eliminate the harmonic wave in electrical network.
For further illustrating topology location and the effect of harmonic wave abatement apparatus 400 of the present invention, take below harmonic wave abatement apparatus 400 as APF/SVG be example, in conjunction with parallel connection type compensation harmonic electric current, APF/SVG describes.It is worthy of note that those skilled in the art notice is same applicable for the harmonic compensation principle of the present invention of series connection or series-parallel connection mode, also within protection scope of the present invention.
Referring to Fig. 5 b, Fig. 5 b is the configuration diagram of the compensation of parallel access APF/SVG compensating power and harmonic wave, and nonlinear load moves in electrical network, and APF/SVG access in parallel electrical network, to the harmonic wave of nonlinear load and idle compensating.I wherein s(figure comprises i sa, i sb, i sc) be source current, i l(figure comprises i la, i lb, i lc) be load current, i m(figure comprises i ma, i mb, i mc) be the offset current that signal of telecommunication feedback device 420 produces.
Referring to Fig. 5 c, the harmonic component that APF/SVG can detect in load current by harmonic measurement device 410 wherein.Harmonic measurement device 410 output harmonic wave current sequence, idle checkout gear 430 can adopt classical Instantaneous Power Theory to calculate and obtain load current fundamental wave reactive power, output reactive current sequence, reactive current sequence and harmonic current sequence are added, and obtain needing reactive current sequence and the harmonic wave current sequence of compensation.Signal of telecommunication feedback device 420 in Fig. 5 c comprises: current controller 421, DC voltage controller 422 and power device 423(are as insulated gate bipolar transistor (IGBT, Insulated Gate Bipolar Transistor)), wherein, current controller 421 is connected with harmonic measurement device 410, idle checkout gear 430, DC voltage controller 422 and power device 423, and DC voltage controller 422 is also connected with power device 423.DC voltage controller 422 is mainly used in output dc voltage conditioning signal.Current controller 421 is mainly used according to DC voltage regulation signal production burst width modulated (PWM, Pulse Width Modulation) the signal output of reactive current sequence, harmonic current sequence and DC voltage controller 422 outputs.Power device 423 is mainly used in producing for compensation harmonic and idle current signal output according to the pwm signal of current controller 421 outputs, with the idle and harmonic current to load, compensates.The offset current i that power device 423 produces m(figure comprises i ma, i mb, i mc) can with load current in harmonic component equal and opposite in direction, opposite direction, thereby the two can cancel each other, and makes in source current only containing basic real component.
The embodiment of the present invention also provides a kind of computer-readable storage medium, and wherein, this computer-readable storage medium can have program stored therein, and this program comprises the part or all of step of the data processing method of recording in said method embodiment while carrying out.
It should be noted that, for aforesaid each embodiment of the method, for simple description, therefore it is all expressed as to a series of combination of actions, but those skilled in the art should know, the embodiment of the present invention is not subject to the restriction of described sequence of movement, because according to the embodiment of the present invention, some step can adopt other orders or carry out simultaneously.Secondly, those skilled in the art also should know, the embodiment described in description all belongs to preferred embodiment, and related action and module might not be that the present invention is necessary.
In the above-described embodiments, the description of each embodiment is all emphasized particularly on different fields, in certain embodiment, there is no the part of detailed description, can be referring to the associated description of other embodiment.
To sum up, in the technical scheme that the embodiment of the present invention provides, the signal of telecommunication of sampling is carried out to the RFFT computing that N orders with the electrical signal sequence that obtains N and order obtain the first sequence of complex numbers from power circuit; The first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers; The second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers; The 3rd sequence of complex numbers is carried out to RFFT computing and obtain the 4th sequence of complex numbers; The 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence, this programme is without carry out conjugate operation before and after FFT, also without data, extract operation, and only need carry out twice actual situation binding operation, simply add reducing, so in terms of existing technologies, comparatively save computing time, and owing to can making full use of RFFT code, carry out computing, so also can save code space.
Further, do not need to increase additional storage space, can code space, number of memory cells and computing time complex optimum.
One of ordinary skill in the art will appreciate that all or part of step in the whole bag of tricks of above-described embodiment is to come the hardware that instruction is relevant to complete by program, this program can be stored in a computer-readable recording medium, and storage medium can comprise: read-only storage, random access memory, disk or CD etc.
A kind of harmonic detecting method and the relevant apparatus that above the embodiment of the present invention are provided are described in detail, applied specific case herein principle of the present invention and embodiment are set forth, the explanation of above embodiment is just for helping to understand method of the present invention and core concept thereof; , for one of ordinary skill in the art, according to thought of the present invention, all will change in specific embodiments and applications, to sum up, this description should not be construed as limitation of the present invention meanwhile.

Claims (12)

1. a harmonic detecting method, is characterized in that, comprising:
The electrical signal sequence that the signal of telecommunication of sampling from power circuit is ordered to obtain N;
The electrical signal sequence that described N is ordered carries out the real number FFT RFFT computing that N orders and obtains the first sequence of complex numbers;
Described the first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers;
Described the second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers;
Described the 3rd sequence of complex numbers is carried out to real number FFT RFFT computing and obtain the 4th sequence of complex numbers; And
Described the 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence.
2. harmonic detecting method according to claim 1, is characterized in that, the described signal of telecommunication of sampling from power circuit comprises with the step of the electrical signal sequence that obtains N and order:
At a signal in the primitive period, the electrical signal sequence that the equally spaced sampling signal of telecommunication is ordered to obtain N from power circuit.
3. harmonic detecting method according to claim 1, is characterized in that, describedly described the first sequence of complex numbers is carried out to the step that harmonic wave extraction process obtains the second sequence of complex numbers comprises:
Remove fundametal compoment in described the first sequence of complex numbers to obtain described the second sequence of complex numbers;
Or,
It is zero to obtain the 5th sequence of complex numbers making the harmonic component in described the first sequence of complex numbers, then with described the first sequence of complex numbers, deducts described the 5th sequence of complex numbers to obtain described the second sequence of complex numbers again.
4. harmonic detecting method according to claim 1, is characterized in that, describedly described the second sequence of complex numbers is carried out to actual situation in conjunction with the step of processing, comprises:
In comprising described second sequence of complex numbers of a plurality of the second plural numbers, except DC component and nyquist frequency are put each second plural number corresponding data, processing mode by actual situation combination generates three plural number corresponding with described each the second plural number, wherein, described the 3rd real equals imaginary part coefficient and the real part sum of corresponding the second plural number, and the imaginary part coefficient of described the 3rd plural number equals the poor of corresponding the second real and imaginary part coefficient.
5. harmonic detecting method according to claim 1, is characterized in that, describedly described the 4th sequence of complex numbers is carried out to actual situation in conjunction with the step of processing, comprises:
In comprising described the 4th sequence of complex numbers of a plurality of the 4th plural numbers, except DC component and nyquist frequency are put each the 4th plural number corresponding data, processing mode by actual situation combination generates six plural number corresponding with described each the 4th plural number, wherein, described the 6th real equals imaginary part coefficient and the real part sum of corresponding the 4th plural number, and the imaginary part coefficient of described the 6th plural number equals the poor of corresponding the 4th real and imaginary part coefficient.
6. according to the harmonic detecting method described in claim 1 to 5 any one, it is characterized in that, the described electrical signal sequence that described N is ordered carries out the step that real number FFT RFFT computing that N orders obtains the first sequence of complex numbers and comprises: the electrical signal sequence that described N is ordered is divided by after described N, then carries out the RFFT computing that N orders and obtain the first sequence of complex numbers;
Or,
Describedly described the first sequence of complex numbers is carried out to the step that harmonic wave extraction process obtains the second sequence of complex numbers comprise: obtain the second sequence of complex numbers described the first sequence of complex numbers is carried out to harmonic wave extraction process after divided by described N again;
Or,
Describedly described the second sequence of complex numbers carried out to actual situation in conjunction with processing, to obtain the step of the 3rd sequence of complex numbers, comprise: to described the second sequence of complex numbers divided by described N after, then carry out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers;
Or, describedly described the 3rd sequence of complex numbers carried out to the step that RFFT computing obtains the 4th sequence of complex numbers comprise: obtain the 4th sequence of complex numbers described the 3rd sequence of complex numbers is carried out to RFFT computing after divided by described N again;
Or,
Describedly described the 4th sequence of complex numbers carried out to actual situation in conjunction with processing, to obtain the step of N point harmonic sequence, comprise: by described the 4th sequence of complex numbers divided by described N after, then carry out actual situation in conjunction with processing to obtain N point harmonic sequence;
Or,
Described harmonic detecting method also comprises:
By the described N point harmonic sequence obtaining divided by described N.
7. a harmonic measurement device, is characterized in that, comprising:
Sampling unit, the electrical signal sequence of ordering to obtain N for the signal of telecommunication of sampling from power circuit;
The one RFFT arithmetic element, the electrical signal sequence of ordering for the N that described sampling unit is obtained carries out the real number FFT RFFT computing that N orders and obtains the first sequence of complex numbers;
Harmonic extraction unit, carries out harmonic wave extraction process for the first sequence of complex numbers that a described RFFT arithmetic element is obtained and obtains the second sequence of complex numbers;
Actual situation, in conjunction with processing unit, is carried out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers for the second sequence of complex numbers that described harmonic extraction unit is obtained;
The 2nd RFFT arithmetic element, carries out RFFT computing for the 3rd sequence of complex numbers that described actual situation is obtained in conjunction with processing unit and obtains the 4th sequence of complex numbers; And
Described actual situation is also carried out actual situation in conjunction with processing to obtain N point harmonic sequence for, the 4th sequence of complex numbers that described the 2nd RFFT arithmetic element is obtained in conjunction with processing unit.
8. harmonic measurement device according to claim 7, is characterized in that,
Described actual situation in conjunction with processing unit specifically for, in described the second sequence of complex numbers that comprises a plurality of the second plural numbers obtaining in described harmonic extraction unit, except DC component and nyquist frequency are put each second plural number corresponding data, processing mode by actual situation combination generates three plural number corresponding with described each the second plural number, wherein, described the 3rd real equals imaginary part coefficient and the real part sum of corresponding the second plural number, the imaginary part coefficient of described the 3rd plural number equals the poor of corresponding the second real and imaginary part coefficient, to obtain comprising the 3rd sequence of complex numbers of a plurality of the 3rd plural numbers.
9. harmonic measurement device according to claim 7, it is characterized in that, described actual situation in conjunction with processing unit also specifically for, in the 4th sequence of complex numbers that comprises a plurality of the 4th plural numbers obtaining in described the 2nd RFFT arithmetic element, except DC component and nyquist frequency are put each the 4th plural number corresponding data, processing mode by actual situation combination generates six plural number corresponding with described each the 4th plural number, wherein, described the 6th real equals imaginary part coefficient and the real part sum of corresponding the 4th plural number, the imaginary part coefficient of described the 6th plural number equals the poor of corresponding the 4th real and imaginary part coefficient, to obtain comprising the N point harmonic sequence of a plurality of the 6th plural numbers.
10. according to the harmonic measurement device described in claim 7 to 9 any one, it is characterized in that,
A described RFFT arithmetic element, then is carried out the RFFT computing that N orders and is obtained the first sequence of complex numbers divided by after described N specifically for, the electrical signal sequence that the N that described sampling unit is obtained is ordered;
Or,
Described harmonic extraction unit specifically for, a described RFFT arithmetic element is carried out to described the first sequence of complex numbers that RFFT computing obtains divided by after described N, then carries out harmonic wave extraction process and obtain the second sequence of complex numbers;
Or,
Described actual situation in conjunction with processing unit specifically for, described the second sequence of complex numbers that described harmonic extraction unit is obtained divided by after described N, then carry out actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers;
Or,
Described the 2nd RFFT arithmetic element, then is carried out RFFT computing and is obtained the 4th sequence of complex numbers divided by after described N specifically for, the 3rd sequence of complex numbers that described actual situation is obtained in conjunction with processing unit;
Or,
Described actual situation in conjunction with processing unit also for, described the 4th sequence of complex numbers that described the 2nd RFFT arithmetic element is obtained divided by after described N, then carry out actual situation in conjunction with processing to obtain N point harmonic sequence;
Or,
Described actual situation is also carried out actual situation in conjunction with processing to obtain N point harmonic sequence for, described the 4th sequence of complex numbers that described the 2nd RFFT arithmetic element is obtained in conjunction with processing unit, and described N point harmonic sequence is exported afterwards divided by described N.
11. 1 kinds of harmonic wave abatement apparatus, is characterized in that, comprising:
Harmonic measurement device, the electrical signal sequence of ordering to obtain N for the signal of telecommunication of sampling from power circuit; The electrical signal sequence that described N is ordered carries out the real number FFT RFFT computing that N orders and obtains the first sequence of complex numbers; Described the first sequence of complex numbers is carried out to harmonic wave extraction process and obtain the second sequence of complex numbers; Described the second sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain the 3rd sequence of complex numbers; Described the 3rd sequence of complex numbers is carried out to RFFT computing and obtain the 4th sequence of complex numbers; Described the 4th sequence of complex numbers is carried out to actual situation in conjunction with processing to obtain N point harmonic sequence output;
Signal of telecommunication feedback device, generates the compensation signal of telecommunication for the described N point harmonic sequence based on described harmonic measurement device output, and the described compensation signal of telecommunication generating is fed back to described power circuit to eliminate the harmonic wave producing in described power circuit.
12. 1 kinds of computer-readable storage mediums, is characterized in that,
Described computer-readable storage medium has program stored therein, and described program comprises the step as described in claim 1 to 6 any one while carrying out.
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