CN105548701A - Method and system for obtaining reduced frequency orthogonal sequence of electric power signal - Google Patents
Method and system for obtaining reduced frequency orthogonal sequence of electric power signal Download PDFInfo
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- CN105548701A CN105548701A CN201510891240.XA CN201510891240A CN105548701A CN 105548701 A CN105548701 A CN 105548701A CN 201510891240 A CN201510891240 A CN 201510891240A CN 105548701 A CN105548701 A CN 105548701A
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
- G01R23/16—Spectrum analysis; Fourier analysis
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- G01R23/167—Spectrum analysis; Fourier analysis using filters with digital filters
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Abstract
The invention discloses a method and system for obtaining a reduced frequency orthogonal sequence of an electric power signal. The method includes the steps of: obtaining an electric power signal preliminary sequence length and a preliminary sequence; performing preliminary frequency measurement on the preliminary sequence, and setting reference frequency; obtaining an electric power signal unit period sequence length and a preset sequence length, and further obtaining an initial forward/inverse sequence; obtaining an initial average initial phase according to the initial forward/inverse sequence; obtaining a secondary forward/inverse sequence and a secondary average initial phase according to an initial phase comparison value of the initial average initial phase and +/-pi/4 and a new initial point; obtaining a cosine/sine function modulation sequence according to the secondary forward/inverse sequence and the secondary average initial phase; and obtaining a first/second/third/fourth multiplication sequence according to preset fine-turning frequency and the cosine/sine function modulation sequence, and further obtaining a reduced frequency orthogonal sequence according to a reduced frequency sine/cosine function sequence. The method provided by the invention improves the degree of accuracy of sine parameter calculation, and is suitable for application.
Description
Technical field
The present invention relates to technical field of electric power, particularly relate to a kind of method and system obtaining the reduction frequency orthogonal sequence of electric power signal.
Background technology
The frequency measurement, phase measurement, amplitude measurement etc. of electric system are the measurement of sine parameter in itself.Fast Fourier Transform (FFT) and discrete Fourier transformation are the basic skills realizing sine parameter measurement, are widely used in electric system.But said method blocks at the non-integer of signal sampling process, causes spectrum leakage, and spectrum leakage can produce corresponding error.
In the measurement of electric system sine parameter, there is many measuring methods, as added window functional based method, adopting interpolation correcting method etc., reduce the impact of spectrum leakage problem.But above-mentioned measuring method measuring accuracy is low, is not suitable for the measurement of pin-point accuracy sine parameter.
Summary of the invention
Based on above-mentioned situation, the present invention proposes a kind of method and system obtaining the reduction frequency orthogonal sequence of electric power signal, improve the accuracy that sine parameter is measured.
To achieve these goals, the embodiment of technical solution of the present invention is:
Obtain a method for the reduction frequency orthogonal sequence of electric power signal, comprise the following steps:
According to the lower limit of frequency power signal scope, default sample frequency and default integer signal period number, obtain the preliminary sequence length of described electric power signal;
According to described preliminary sequence length, described electric power signal is sampled, obtain the preliminary sequence of described electric power signal;
Frequency preliminary survey is carried out to described preliminary sequence, generates the first synchronizing frequency of described electric power signal, and according to described preliminary frequency setting the reference frequency of electric power signal;
According to described default sample frequency and described reference frequency, obtain the unit period sequence length of described electric power signal;
According to described default integer signal period number and described unit period sequence length, obtain the predetermined sequence length of described electric power signal;
According to default starting point and described predetermined sequence length, from described preliminary sequence, obtain the first forward sequence of described electric power signal;
The first anti-pleat sequence of described electric power signal is obtained according to described first forward sequence;
Obtain the first positive phase of described electric power signal according to described first forward sequence, and obtain the first antiphase of described electric power signal according to described first anti-pleat sequence;
The first average initial phase of described electric power signal is obtained according to described first positive phase and described first antiphase;
Described first average initial phase and ± π/4 are compared, obtains the first phase compare value compared with described ± π/4, and according to described first phase compare value and described default starting point, obtain new starting point;
According to described new starting point and described predetermined sequence length, from described preliminary sequence, obtain the sequence of forward again of described electric power signal, and obtain the again anti-pleat sequence of described electric power signal according to the described sequence of forward again;
Obtain the positive phase again of described electric power signal according to the described sequence of forward again, and obtain the antiphase again of described electric power signal according to described anti-pleat sequence again;
The again average initial phase of described electric power signal is obtained according to described positive phase again and described antiphase again;
The described sequence of forward again and described anti-pleat sequence are again added, and according to the result after addition and described average initial phase again, obtain the cosine function modulation sequence of described electric power signal;
The described sequence of forward again and described anti-pleat sequence are again subtracted each other, and according to the result after subtracting each other and described average initial phase again, obtains the sine function modulation sequence of described electric power signal;
The discrete sine function of default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the first multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described sine function modulation sequence and obtains the second multiplication sequence of described electric power signal, the discrete sine function of default fine setting frequency is multiplied with described sine function modulation sequence and obtains the 3rd multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the 4th multiplication sequence of described electric power signal,
Described second multiplication sequence and described first multiplication sequence are subtracted each other, obtains the reduction frequency sine sequence of function of described electric power signal; Described 4th multiplication sequence is added with described 3rd multiplication sequence, obtains the reduction frequency cosine function sequence of described electric power signal;
The reduction frequency orthogonal sequence of described electric power signal is obtained according to the described reduction frequency sine sequence of function and described reduction frequency cosine function sequence.
Obtain a system for the reduction frequency orthogonal sequence of electric power signal, comprising:
Preliminary sequence length modules, for the lower limit according to frequency power signal scope, presets sample frequency and default integer signal period number, obtains the preliminary sequence length of described electric power signal;
Preliminary sequence module, for sampling to described electric power signal according to described preliminary sequence length, obtains the preliminary sequence of described electric power signal;
Frequency preliminary survey module, for carrying out frequency preliminary survey to described preliminary sequence, generates the first synchronizing frequency of described electric power signal, and according to described preliminary frequency setting the reference frequency of electric power signal;
Unit period sequence length module, for according to described default sample frequency and described reference frequency, obtains the unit period sequence length of described electric power signal;
Predetermined sequence length modules, for according to described default integer signal period number and described unit period sequence length, obtains the predetermined sequence length of described electric power signal;
First forward block, for according to presetting starting point and described predetermined sequence length, obtains the first forward sequence of described electric power signal from described preliminary sequence;
First anti-pleat block, for obtaining the first anti-pleat sequence of described electric power signal according to described first forward sequence;
First phase module, for obtaining the first positive phase of described electric power signal according to described first forward sequence, and obtains the first antiphase of described electric power signal according to described first anti-pleat sequence;
First average initial phase module, for obtaining the first average initial phase of described electric power signal according to described first positive phase and described first antiphase;
Phase compare module, for described first average initial phase and ± π/4 being compared, obtaining the first phase compare value compared with described ± π/4, and according to described first phase compare value and described default starting point, obtaining new starting point;
Block again, for according to described new starting point and described predetermined sequence length, obtains the sequence of forward again of described electric power signal, and obtains the again anti-pleat sequence of described electric power signal according to the described sequence of forward again from described preliminary sequence;
Phase module again, for obtaining the positive phase again of described electric power signal according to the described sequence of forward again, and obtains the antiphase again of described electric power signal according to described anti-pleat sequence again;
Average initial phase module again, for obtaining the again average initial phase of described electric power signal according to described positive phase again and described antiphase again;
Cosine function modulation sequence module, for the described sequence of forward again and described anti-pleat sequence being again added, and according to the result after addition and described average initial phase again, obtains the cosine function modulation sequence of described electric power signal;
Sine function modulation sequence module, for the described sequence of forward again and described anti-pleat sequence again being subtracted each other, and according to the result after subtracting each other and described average initial phase again, obtains the sine function modulation sequence of described electric power signal;
Multiplication sequence module, the first multiplication sequence of described electric power signal is obtained for the discrete sine function of default fine setting frequency being multiplied with described cosine function modulation sequence, the discrete cosine function of described default fine setting frequency is multiplied with described sine function modulation sequence and obtains the second multiplication sequence of described electric power signal, the discrete sine function of default fine setting frequency is multiplied with described sine function modulation sequence and obtains the 3rd multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the 4th multiplication sequence of described electric power signal,
Reducing frequency function block, for described second multiplication sequence and described first multiplication sequence being subtracted each other, obtaining the reduction frequency sine sequence of function of described electric power signal; Described 4th multiplication sequence is added with described 3rd multiplication sequence, obtains the reduction frequency cosine function sequence of described electric power signal;
Reduce frequency orthogonal block, for obtaining the reduction frequency orthogonal sequence of described electric power signal according to the described reduction frequency sine sequence of function and described reduction frequency cosine function sequence.
Compared with prior art, beneficial effect of the present invention is: the present invention obtains the method and system of the reduction frequency orthogonal sequence of electric power signal, according to the lower limit of frequency power signal scope, preset sample frequency and just establish integer signal period number, obtain preliminary sequence length, and electric power signal is tentatively sampled, obtain preliminary sequence; Frequency preliminary survey is carried out to preliminary sequence, generates just synchronizing frequency, setting reference frequency; According to default sample frequency and reference frequency, obtain unit period sequence length; According to default integer signal period number and unit period sequence length, obtain predetermined sequence length; From preliminary sequence, obtain first forward sequence, obtain first anti-pleat sequence further; Obtain first positive phase, first antiphase according to first forward sequence, first anti-pleat sequence, obtain first average initial phase further; Compare obtain first phase compare value with ± π/4, obtain new starting point further; According to new starting point and predetermined sequence length, obtain again forward sequence, again anti-pleat sequence, obtain again positive phase, again antiphase, again average initial phase further; According to positive phase, again antiphase, again average initial phase obtain cosine function modulation sequence, sine function modulation sequence again; Obtain reduce the frequency sine sequence of function, reduction frequency cosine function sequence according to default fine setting frequency, cosine function modulation sequence, sine function modulation sequence, be reduced frequency orthogonal sequence further, by reducing the fundamental frequency of burst, can realize blocking the number of cycles of fundamental signal, with the amplitude maximum of first-harmonic composition in electric power signal, solve the number of cycles truncated problem of fundamental signal, improve the accuracy that sine parameter calculates, be applicable to practical application.
Accompanying drawing explanation
Fig. 1 is the method flow diagram of the reduction frequency orthogonal sequence obtaining electric power signal in an embodiment;
Fig. 2 is first forward sequence and first anti-pleat sequence diagram in an embodiment;
Fig. 3 is the system architecture schematic diagram of the reduction frequency orthogonal sequence obtaining electric power signal in an embodiment.
Embodiment
In order to make the object, technical solutions and advantages of the present invention clearly, below in conjunction with accompanying drawing, the present invention is described in further detail.
Although the step in the present invention arranges with label, and be not used in and limit the precedence of step, the order of step or the execution of certain step need based on other steps unless expressly stated, otherwise the relative rank of step is adjustable.
Obtain the method for the reduction frequency orthogonal sequence of electric power signal in an embodiment, as shown in Figure 1, comprise the following steps:
Step S101: according to the lower limit of frequency power signal scope, default sample frequency and default integer signal period number, obtain the preliminary sequence length of described electric power signal;
Step S102: according to described preliminary sequence length, described electric power signal is sampled, obtain the preliminary sequence of described electric power signal;
Step S103: carry out frequency preliminary survey to described preliminary sequence, generates the first synchronizing frequency of described electric power signal, and according to described preliminary frequency setting the reference frequency of electric power signal;
Step S104: according to described default sample frequency and described reference frequency, obtains the unit period sequence length of described electric power signal;
Step S105: according to described default integer signal period number and described unit period sequence length, obtain the predetermined sequence length of described electric power signal;
Step S106: according to default starting point and described predetermined sequence length, obtains the first forward sequence of described electric power signal from described preliminary sequence;
Step S107: the first anti-pleat sequence obtaining described electric power signal according to described first forward sequence;
Step S108: the first positive phase obtaining described electric power signal according to described first forward sequence, and the first antiphase obtaining described electric power signal according to described first anti-pleat sequence;
Step S109: the first average initial phase obtaining described electric power signal according to described first positive phase and described first antiphase;
Step S110: described first average initial phase and ± π/4 are compared, obtains the first phase compare value compared with described ± π/4, and according to described first phase compare value and described default starting point, obtain new starting point;
Step S111: according to described new starting point and described predetermined sequence length, obtains the sequence of forward again of described electric power signal from described preliminary sequence, and obtains the again anti-pleat sequence of described electric power signal according to the described sequence of forward again;
Step S112: the positive phase again obtaining described electric power signal according to the described sequence of forward again, and obtain the antiphase again of described electric power signal according to described anti-pleat sequence again;
Step S113: the again average initial phase obtaining described electric power signal according to described positive phase again and described antiphase again;
Step S114: the described sequence of forward again and described anti-pleat sequence are again added, and according to the result after addition and described average initial phase again, obtain the cosine function modulation sequence of described electric power signal;
Step S115: the described sequence of forward again and described anti-pleat sequence are again subtracted each other, and according to the result after subtracting each other and described average initial phase again, obtain the sine function modulation sequence of described electric power signal;
Step S116: the discrete sine function of default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the first multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described sine function modulation sequence and obtains the second multiplication sequence of described electric power signal, the discrete sine function of default fine setting frequency is multiplied with described sine function modulation sequence and obtains the 3rd multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the 4th multiplication sequence of described electric power signal,
Step S117: described second multiplication sequence and described first multiplication sequence are subtracted each other, obtains the reduction frequency sine sequence of function of described electric power signal; Described 4th multiplication sequence is added with described 3rd multiplication sequence, obtains the reduction frequency cosine function sequence of described electric power signal;
Step S118: the reduction frequency orthogonal sequence obtaining described electric power signal according to the described reduction frequency sine sequence of function and described reduction frequency cosine function sequence.
Known from the above description, the present invention obtains and reduces frequency orthogonal sequence, and improve the accuracy that sine parameter calculates, actual application value is high.
Wherein, described electric power signal is a kind of first-harmonic composition is main sinusoidal signal.Sinusoidal signal is extensively made a comment or criticism string function signal and cosine function signal.
In one embodiment, power system frequency scope at 45Hz-55Hz, power taking force signal lower-frequency limit f
minfor 45Hz; Described default integer signal period number C is set according to actual needs
2 π, in one embodiment, get C
2 πbe 13.In one embodiment, for step S101, obtaining described preliminary sequence length is formula (1):
In formula, N
startfor preliminary sequence length; (int) expression rounds; C
2 πfor default integer signal period number; f
minfor the lower limit of frequency power signal scope, unit Hz; F is for presetting sample frequency, unit Hz.
In one embodiment, described electric power signal is the cosine function signal of single fundamental frequency, and for step S102, the preliminary sequence obtaining described electric power signal is formula (2):
Wherein, X
startn () is described preliminary sequence; A is signal amplitude, unit v; ω
ifor signal frequency, T is sampling interval duration, and f is for presetting sample frequency, and unit Hz, n are series of discrete number,
for preliminary sequence initial phase, N
startfor preliminary sequence length.
For step S103, by zero friendship method, based on the algorithm of filtering, based on Wavelet Transformation Algorithm, the algorithm based on neural network, the frequency algorithm based on DFT conversion or carry out frequency preliminary survey based on the frequency algorithm of phase differential to described preliminary sequence, obtain described just synchronizing frequency.
In one embodiment, generating described just synchronizing frequency is formula (3):
ω
o(3);
Wherein, ω
ofor first synchronizing frequency; Preferably, described reference frequency equals described just synchronizing frequency is formula (4):
ω
s=ω
o(4);
Wherein, ω
sfor reference frequency, ω
ofor first synchronizing frequency.
In one embodiment, for step S104, the unit period sequence length obtaining described electric power signal is formula (5):
In formula, N
2 πfor described unit period sequence length; (int) be round numbers; F is for presetting sample frequency, unit Hz; ω
sfor reference frequency.
There is the error in 1 sampling interval in described unit period sequence length integer.
In one embodiment, for step S105, obtaining described predetermined sequence length is formula (6):
N=(int)[(C
2π-1)N
2π](6);
Wherein, N is predetermined sequence length, and (int) is round numbers, N
2 πfor described unit period sequence length, C
2 πfor default integer signal period number.
In one embodiment, default starting point is 0.5 times of described unit period sequence length;
In one embodiment, for step S106, obtaining described first forward sequence is formula (7):
Wherein, X
startn () is preliminary sequence, X
+ startn () is first forward sequence, P
startpreset starting point, N
2 πfor described unit period sequence length, (int) is round numbers, and A is signal amplitude, unit v, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number,
for first forward sequence initial phase, N predetermined sequence length.First forward sequence pattern is expressed, shown in Fig. 2.
In one embodiment, for step S107, obtaining first anti-pleat sequence is formula (8):
Wherein, X
-start(-n) is first anti-pleat sequence, X
+ start(n) for first forward sequence, A be signal amplitude, unit v, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number, and β 1 is first anti-pleat sequence initial phase, N predetermined sequence length.The avatars of described first anti-pleat sequence, as shown in Figure 2.
In one embodiment, first positive phase and first antiphase are the results based on quadrature downconvert and integral and calculating, when not considering the mixing interfering frequency of quadrature downconvert, quadrature downconvert is expressed as formula (9), and integral and calculating is expressed as formula (10):
Wherein, R
+ startn () is the first positive real sequence of mixing frequently, I
+ startn () is first weakened body resistance frequency mixing sequence, R
-start(-n) is the first anti-real sequence of mixing frequently, I
-start(-n) is the first anti-empty sequence of mixing frequently, cos (ω
sor cos (-ω Tn)
stn) be the discrete cosine function of reference frequency, sin (ω
sor sin (-ω Tn)
stn) be the discrete sine function of reference frequency, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number,
for first forward sequence initial phase, β 1 is first anti-pleat sequence initial phase, and N is predetermined sequence length.
In formula, R
+ startfirst positive real integrated value, unit dimensionless frequently, I
+ startfor first weakened body resistance frequency integrated value, unit dimensionless, R
-startfor first anti-real integrated value, unit dimensionless frequently, I
-startfor the first anti-empty integrated value of mixing frequently, unit dimensionless, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length,
for first forward sequence initial phase, β 1 is first anti-pleat sequence initial phase.
In one embodiment, for step S108, obtain the expression formula of first positive phase and first antiphase for (11):
In formula, PH
+ startfor first positive phase, PH
-startfor first antiphase, R
+ startfirst positive real integrated value, unit dimensionless frequently, I
+ startfor first weakened body resistance frequency integrated value, unit dimensionless, R
-startfor first anti-real integrated value, unit dimensionless frequently, I
-startfor the first anti-empty integrated value of mixing frequently, unit dimensionless, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, T is sampling interval duration, and N is predetermined sequence length,
for first forward sequence initial phase, β 1 is first anti-pleat sequence initial phase.
In one embodiment, for step S109, the expression formula obtaining first average initial phase is (12):
In formula, PH
start-avgfor first average initial phase, PH
+ startfor first positive phase, PH
-startfor first antiphase,
for first forward sequence initial phase, β 1 is first anti-pleat sequence initial phase.
In one embodiment, for step S110, by described first average initial phase and PH
start-avgwith ± π/4 compare as formula (13):
In formula, Δ PH
comfor first phase compare value, unit rad, PH
start-avgfor first average initial phase.
In one embodiment, obtaining described new starting point is formula (14):
In formula, P
newfor new starting point, unit dimensionless, P
startfor default starting point, Δ PH
comfor first phase compare value, unit rad, N
2 πfor unit periodic sequence length, (int) is round numbers.
In one embodiment, for step S111, again forward sequence and again anti-pleat sequence be formula (15):
In formula, X
+ endn () is again forward sequence, X
-end(-n) is again anti-pleat sequence, P
newfor new starting point, unit dimensionless,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length.
In one embodiment, again positive phase and again antiphase be the result calculated based on quadrature downconvert and digital filtering.Described digital filtering is made up of 6 grades of rectangular window arithmetic mean filter of 2 kinds of filtering parameters.
When not considering the mixing interfering frequency of quadrature downconvert, quadrature downconvert is expressed as formula (16), and 6 grades of rectangular window arithmetic mean filter filtering calculation expressions of 2 kinds of filtering parameters are formula (17):
In formula, R
+ endn () is again the positive real sequence of mixing frequently, I
+ endn () is again weakened body resistance frequency mixing sequence, R
-end(-n) is again the anti-real sequence of mixing frequently, I
-end(-n) is again the anti-empty sequence of mixing frequently, cos (ω
sor cos (-ω Tn)
stn) be the discrete cosine function of reference frequency, sin (ω
sor sin (-ω Tn)
stn) be the discrete sine function of reference frequency, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase, and N is predetermined sequence length.
In formula, R
+ endfor positive real digital filtering final value frequently again, unit dimensionless; I
+ endfor weakened body resistance frequency digital filtering final value again, unit dimensionless; R
-endfor anti-digital filtering final value again, unit dimensionless; I
-endfor anti-empty digital filtering final value frequently again, unit dimensionless; Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference; K (Ω) for digital filtering is in the amplitude gain of frequency difference Ω, unit dimensionless; T is sampling interval duration;
for forward sequence initial phase again; β 2 is again anti-pleat sequence initial phase; N
d1for filtering parameter 1, namely to N
d1individual continuous discrete value is added, and then gets its arithmetic mean and exports as this filter value; N
d2for filtering parameter 2, namely to N
d2individual continuous discrete value is added, and then gets its arithmetic mean and exports as this filter value; N
dfor digital filtering uses sequence length, be quantitatively the summation of 6 grades of rectangular window arithmetic mean filter filtering parameters, be less than or equal to predetermined sequence length N.
In one embodiment, filtering parameter N
d1value is 1.5 times of the unit period sequence length of described reference frequency, and object carries out degree of depth suppression to the mixing interfering frequency that 1/3 subharmonic produces; Filtering parameter N
d2value is 2 times of the unit period sequence length of described reference frequency, and object carries out degree of depth suppression to the mixing interfering frequency that direct current, 1/2 gradation, subharmonic etc. produce.6 grades of rectangular window arithmetic mean filter filtering of 2 kinds of filtering parameters calculate 10.5 times that need to use signal period sequence length.
Filtering parameter N
d1with filtering parameter N
d2expression formula is formula (18):
In formula, N
d1for digital filter parameters 1, unit dimensionless, (int) is round numbers, N
d2for digital filter parameters 2, unit dimensionless, N
2 πfor unit periodic sequence length.
In one embodiment, for step S112, again positive phase and again antiphase expression formula be (19):
In formula, PH
+ endfor positive phase again, PH
-endfor antiphase again, R
+ endfor positive real integrated value frequently again, unit dimensionless, I
+ endfor weakened body resistance frequency integrated value again, unit dimensionless, R
-endfor anti-real integrated value frequently again, unit dimensionless, I
-endfor the anti-empty integrated value of mixing frequently again, unit dimensionless, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, T is sampling interval duration, N
dfor digital filtering uses sequence length,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase.
In one embodiment, for step S113, the expression formula obtaining again average initial phase is (20):
In formula, PH
end-avgfor average initial phase again, PH
+ endfor positive phase again, PH
-endfor antiphase again,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase.
In one embodiment, for step S114, obtaining cosine function modulation sequence expression formula is (21):
In formula, X
cosn () is cosine function modulation sequence; A is cosine function modulation sequence amplitude, unit v;
for cosine function modulation sequence initial phase, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase.
In one embodiment, for step S115, obtaining sine function modulation sequence expression formula is (22):
In formula, X
sinn () is sine function modulation sequence, A is sine function modulation sequence amplitude, unit v,
for cosine function modulation sequence initial phase, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase.
In one embodiment, described default fine setting frequency is the arithmetic number being less than or equal to actual signal frequency 1%, and unit rad/s is expressed as formula (23):
In formula, Ω
setfor fine setting frequency, unit rad/s, Ω
set≤ 0.01 ω
i.
For step S116, acquisition first multiplication sequence that the discrete sine function of described fine setting frequency is multiplied with described cosine function modulation sequence is formula (24):
For step S116, acquisition second multiplication sequence that is multiplied with described sine function modulation sequence by the discrete cosine function of described fine setting frequency is formula (25):
For step S116, the 3rd multiplication sequence obtaining described electric power signal that the discrete sine function of default fine setting frequency is multiplied with described sine function modulation sequence is formula (26):
For step S116, the 4th multiplication sequence obtaining described electric power signal that is multiplied with described cosine function modulation sequence by the discrete cosine function of described default fine setting frequency is formula (27):
In formula, X1 (n) is the first multiplication sequence, and X2 (n) is the second multiplication sequence, and X3 (n) is the first multiplication sequence, and X4 (n) is the second multiplication sequence, sin (Ω
settn) be the discrete sine function of described fine setting frequency, cos (Ω
settn) be the discrete cosine function of described fine setting frequency.
In one embodiment, for step S117, obtaining the reduction frequency sine sequence of function is formula (28):
In one embodiment, for step S117, obtaining reduction frequency cosine function sequence is formula (29):
In formula, X
sin+fn () is for reducing the frequency sine sequence of function, X
cos+fn (), for reducing frequency cosine function sequence, sequence frequency reduces Ω
set.
In one embodiment, for step S118, obtaining reduction frequency orthogonal sequence is formula (30):
In formula, sequence X
sin+f(n) and sequence X
cos+fn () is orthogonal each other.
Obtain the system of the reduction frequency orthogonal sequence of electric power signal in an embodiment, as shown in Figure 3, comprising:
Preliminary sequence length modules 301, for the lower limit according to frequency power signal scope, presets sample frequency and default integer signal period number, obtains the preliminary sequence length of described electric power signal;
Preliminary sequence module 302, for sampling to described electric power signal according to described preliminary sequence length, obtains the preliminary sequence of described electric power signal;
Frequency preliminary survey module 303, for carrying out frequency preliminary survey to described preliminary sequence, generates the first synchronizing frequency of described electric power signal, and according to described preliminary frequency setting the reference frequency of electric power signal;
Unit period sequence length module 304, for according to described default sample frequency and described reference frequency, obtains the unit period sequence length of described electric power signal;
Predetermined sequence length modules 305, for according to described default integer signal period number and described unit period sequence length, obtains the predetermined sequence length of described electric power signal;
First forward block 306, for according to presetting starting point and described predetermined sequence length, obtains the first forward sequence of described electric power signal from described preliminary sequence;
First anti-pleat block 307, for obtaining the first anti-pleat sequence of described electric power signal according to described first forward sequence;
First phase module 308, for obtaining the first positive phase of described electric power signal according to described first forward sequence, and obtains the first antiphase of described electric power signal according to described first anti-pleat sequence;
First average initial phase module 309, for obtaining the first average initial phase of described electric power signal according to described first positive phase and described first antiphase;
Phase compare module 310, for described first average initial phase and ± π/4 being compared, obtaining the first phase compare value compared with described ± π/4, and according to described first phase compare value and described default starting point, obtaining new starting point;
Block 311 again, for according to described new starting point and described predetermined sequence length, obtains the sequence of forward again of described electric power signal, and obtains the again anti-pleat sequence of described electric power signal according to the described sequence of forward again from described preliminary sequence;
Phase module 312 again, for obtaining the positive phase again of described electric power signal according to the described sequence of forward again, and obtains the antiphase again of described electric power signal according to described anti-pleat sequence again;
Average initial phase module 313 again, for obtaining the again average initial phase of described electric power signal according to described positive phase again and described antiphase again;
Cosine function modulation sequence module 314, for the described sequence of forward again and described anti-pleat sequence being again added, and according to the result after addition and described average initial phase again, obtains the cosine function modulation sequence of described electric power signal;
Sine function modulation sequence module 315, for the described sequence of forward again and described anti-pleat sequence again being subtracted each other, and according to the result after subtracting each other and described average initial phase again, obtains the sine function modulation sequence of described electric power signal;
Multiplication sequence module 316, the first multiplication sequence of described electric power signal is obtained for the discrete sine function of default fine setting frequency being multiplied with described cosine function modulation sequence, the discrete cosine function of described default fine setting frequency is multiplied with described sine function modulation sequence and obtains the second multiplication sequence of described electric power signal, the discrete sine function of default fine setting frequency is multiplied with described sine function modulation sequence and obtains the 3rd multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the 4th multiplication sequence of described electric power signal,
Reducing frequency function block 317, for described second multiplication sequence and described first multiplication sequence being subtracted each other, obtaining the reduction frequency sine sequence of function of described electric power signal; Described 4th multiplication sequence is added with described 3rd multiplication sequence, obtains the reduction frequency cosine function sequence of described electric power signal;
Reduce frequency orthogonal block 318, for obtaining the reduction frequency orthogonal sequence of described electric power signal according to the described reduction frequency sine sequence of function and described reduction frequency cosine function sequence.
Known from the above description, the present invention obtains and reduces frequency orthogonal sequence, improves the accuracy that sine parameter calculates, meets actual needs.
Wherein, described electric power signal is a kind of first-harmonic composition is main sinusoidal signal.Sinusoidal signal is extensively made a comment or criticism string function signal and cosine function signal.
In one embodiment, power system frequency scope at 45Hz-55Hz, power taking force signal lower-frequency limit f
minfor 45Hz; In one embodiment, C is got
2 πbe 13.In one embodiment, preliminary sequence length modules 301 obtains described preliminary sequence length is formula (1):
In formula, N
startfor preliminary sequence length; (int) expression rounds; C
2 πfor default integer signal period number; f
minfor the lower limit of frequency power signal scope, unit Hz; F is for presetting sample frequency, unit Hz.
In one embodiment, described electric power signal is the cosine function signal of single fundamental frequency, and the preliminary sequence that preliminary sequence module 302 obtains described electric power signal is formula (2):
Wherein, X
startn () is described preliminary sequence; A is signal amplitude, unit v; ω
ifor signal frequency, T is sampling interval duration, and f is for presetting sample frequency, and unit Hz, n are series of discrete number,
for preliminary sequence initial phase, N
startfor preliminary sequence length.
Frequency preliminary survey module 303 is by zero friendship method, based on the algorithm of filtering, based on Wavelet Transformation Algorithm, the algorithm based on neural network, the frequency algorithm based on DFT conversion or carry out frequency preliminary survey based on the frequency algorithm of phase differential to described preliminary sequence, obtain described just synchronizing frequency.
In one embodiment, generating described just synchronizing frequency is formula (3):
ω
o(3);
Wherein, ω
ofor first synchronizing frequency; Preferably, described reference frequency equals described just synchronizing frequency is formula (4):
ω
s=ω
o(4);
Wherein, ω
sfor reference frequency, ω
ofor first synchronizing frequency.
In one embodiment, unit period sequence length module 304 obtains the unit period sequence length of described electric power signal is formula (5):
In formula, N
2 πfor described unit period sequence length; (int) be round numbers; F is for presetting sample frequency, unit Hz; ω
sfor reference frequency.
There is the error in 1 sampling interval in described unit period sequence length integer.
In one embodiment, predetermined sequence length modules 305 obtains described predetermined sequence length is formula (6):
N=(int)[(C
2π-1)N
2π](6);
Wherein, N is predetermined sequence length, and (int) is round numbers, N
2 πfor described unit period sequence length, C
2 πfor default integer signal period number.
In one embodiment, default starting point is 0.5 times of described unit period sequence length;
In one embodiment, first forward block 306 obtains described first forward sequence is formula (7):
Wherein, X
startn () is preliminary sequence, X
+ startn () is first forward sequence, P
startpreset starting point, N
2 πfor described unit period sequence length, (int) is round numbers, and A is signal amplitude, unit v, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number,
for first forward sequence initial phase, N predetermined sequence length.First forward sequence pattern is expressed, shown in Fig. 2.
In one embodiment, first anti-pleat block 307 obtains first anti-pleat sequence is formula (8):
Wherein, X
-start(-n) is first anti-pleat sequence, X
+ start(n) for first forward sequence, A be signal amplitude, unit v, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number, and β 1 is first anti-pleat sequence initial phase, N predetermined sequence length.The avatars of described first anti-pleat sequence, as shown in Figure 2.
In one embodiment, first positive phase and first antiphase are the results based on quadrature downconvert and integral and calculating, when not considering the mixing interfering frequency of quadrature downconvert, quadrature downconvert is expressed as formula (9), and integral and calculating is expressed as formula (10):
Wherein, R
+ startn () is the first positive real sequence of mixing frequently, I
+ startn () is first weakened body resistance frequency mixing sequence, R
-start(-n) is the first anti-real sequence of mixing frequently, I
-start(-n) is the first anti-empty sequence of mixing frequently, cos (ω
sor cos (-ω Tn)
stn) be the discrete cosine function of reference frequency, sin (ω
sor sin (-ω Tn)
stn) be the discrete sine function of reference frequency, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number,
for first forward sequence initial phase, β 1 is first anti-pleat sequence initial phase, and N is predetermined sequence length.
In formula, R
+ startfirst positive real integrated value, unit dimensionless frequently, I
+ startfor first weakened body resistance frequency integrated value, unit dimensionless, R
-startfor first anti-real integrated value, unit dimensionless frequently, I
-startfor the first anti-empty integrated value of mixing frequently, unit dimensionless, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length,
for first forward sequence initial phase, β 1 is first anti-pleat sequence initial phase.
In one embodiment, first phase module 308 obtains the expression formula of first positive phase and first antiphase for (11):
In formula, PH
+ startfor first positive phase, PH
-startfor first antiphase, R
+ startfirst positive real integrated value, unit dimensionless frequently, I
+ startfor first weakened body resistance frequency integrated value, unit dimensionless, R
-startfor first anti-real integrated value, unit dimensionless frequently, I
-startfor the first anti-empty integrated value of mixing frequently, unit dimensionless, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, T is sampling interval duration, and N is predetermined sequence length,
for first forward sequence initial phase, β 1 is first anti-pleat sequence initial phase.
In one embodiment, first average initial phase module 309 obtains first average initial phase is formula (12):
In formula, PH
start-avgfor first average initial phase, PH
+ startfor first positive phase, PH
-startfor first antiphase,
for first forward sequence initial phase, β 1 is first anti-pleat sequence initial phase.
In one embodiment, phase compare module 310 is by described first average initial phase and PH
start-avgwith ± π/4 compare as formula (13):
In formula, Δ PH
comfor first phase compare value, unit rad, PH
start-avgfor first average initial phase.
In one embodiment, obtaining described new starting point is formula (14):
In formula, P
newfor new starting point, unit dimensionless, P
startfor default starting point, Δ PH
comfor first phase compare value, unit rad, N
2 πfor unit periodic sequence length, (int) is round numbers.
In one embodiment, again block 311 obtain again forward sequence and again anti-pleat sequence be formula (15):
In formula, X
+ endn () is again forward sequence, X
-end(-n) is again anti-pleat sequence, P
newfor new starting point, unit dimensionless,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length.
In one embodiment, again positive phase and again antiphase be the result calculated based on quadrature downconvert and digital filtering.Described digital filtering is made up of 6 grades of rectangular window arithmetic mean filter of 2 kinds of filtering parameters.
When not considering the mixing interfering frequency of quadrature downconvert, quadrature downconvert is expressed as formula (16), and 6 grades of rectangular window arithmetic mean filter filtering calculation expressions of 2 kinds of filtering parameters are formula (17):
In formula, R
+ endn () is again the positive real sequence of mixing frequently, I
+ endn () is again weakened body resistance frequency mixing sequence, R
-end(-n) is again the anti-real sequence of mixing frequently, I
-end(-n) is again the anti-empty sequence of mixing frequently, cos (ω
sor cos (-ω Tn)
stn) be the discrete cosine function of reference frequency, sin (ω
sor sin (-ω Tn)
stn) be the discrete sine function of reference frequency, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase, and N is predetermined sequence length.
In formula, R
+ endfor positive real digital filtering final value frequently again, unit dimensionless; I
+ endfor weakened body resistance frequency digital filtering final value again, unit dimensionless; R
-endfor anti-digital filtering final value again, unit dimensionless; I
-endfor anti-empty digital filtering final value frequently again, unit dimensionless; Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference; K (Ω) for digital filtering is in the amplitude gain of frequency difference Ω, unit dimensionless; T is sampling interval duration;
for forward sequence initial phase again; β 2 is again anti-pleat sequence initial phase; N
d1for filtering parameter 1, namely to N
d1individual continuous discrete value is added, and then gets its arithmetic mean and exports as this filter value; N
d2for filtering parameter 2, namely to N
d2individual continuous discrete value is added, and then gets its arithmetic mean and exports as this filter value; N
dfor digital filtering uses sequence length, be quantitatively the summation of 6 grades of rectangular window arithmetic mean filter filtering parameters, be less than or equal to predetermined sequence length N.
In one embodiment, filtering parameter N
d1value is 1.5 times of the unit period sequence length of described reference frequency, and object carries out degree of depth suppression to the mixing interfering frequency that 1/3 subharmonic produces; Filtering parameter N
d2value is 2 times of the unit period sequence length of described reference frequency, and object carries out degree of depth suppression to the mixing interfering frequency that direct current, 1/2 gradation, subharmonic etc. produce.6 grades of rectangular window arithmetic mean filter filtering of 2 kinds of filtering parameters calculate 10.5 times that need to use signal period sequence length.
Filtering parameter N
d1with filtering parameter N
d2expression formula is formula (18):
In formula, N
d1for digital filter parameters 1, unit dimensionless, (int) is round numbers, N
d2for digital filter parameters 2, unit dimensionless, N
2 πfor unit periodic sequence length.
In one embodiment, again phase module 312 obtain again positive phase and again antiphase expression formula for (19):
In formula, PH
+ endfor positive phase again, PH
-endfor antiphase again, R
+ endfor positive real integrated value frequently again, unit dimensionless, I
+ endfor weakened body resistance frequency integrated value again, unit dimensionless, R
-endfor anti-real integrated value frequently again, unit dimensionless, I
-endfor the anti-empty integrated value of mixing frequently again, unit dimensionless, Ω is signal frequency ω
iwith reference frequency ω
sfrequency difference, T is sampling interval duration, N
dfor digital filtering uses sequence length,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase.
In one embodiment, average initial phase module 313 obtains again the expression formula of average initial phase for (20) again:
In formula, PH
end-avgfor average initial phase again, PH
+ endfor positive phase again, PH
-endfor antiphase again,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase.
In one embodiment, cosine function modulation sequence module 314 obtains cosine function modulation sequence expression formula for (21):
In formula, X
cosn () is cosine function modulation sequence; A is cosine function modulation sequence amplitude, unit v;
for cosine function modulation sequence initial phase, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase.
In one embodiment, sine function modulation sequence module 315 obtains sine function modulation sequence expression formula for (22):
In formula, X
sinn () is sine function modulation sequence, A is sine function modulation sequence amplitude, unit v,
for cosine function modulation sequence initial phase, ω
ifor signal frequency, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length,
for forward sequence initial phase again, β 2 is again anti-pleat sequence initial phase.
In one embodiment, described default fine setting frequency is the arithmetic number being less than or equal to actual signal frequency 1%, and unit rad/s is expressed as formula (23):
In formula, Ω
setfor fine setting frequency, unit rad/s, Ω
set≤ 0.01 ω
i.
It is formula (24) that multiplication sequence module 316 obtains the first multiplication sequence:
It is formula (25) that multiplication sequence module 316 obtains the second multiplication sequence:
The 3rd multiplication sequence that multiplication sequence module 316 obtains described electric power signal is formula (26):
The 4th multiplication sequence that multiplication sequence module 316 obtains described electric power signal is formula (27):
In formula, X1 (n) is the first multiplication sequence, and X2 (n) is the second multiplication sequence, and X3 (n) is the first multiplication sequence, and X4 (n) is the second multiplication sequence, sin (Ω
settn) be the discrete sine function of described fine setting frequency, cos (Ω
settn) be the discrete cosine function of described fine setting frequency.
In one embodiment, reducing the frequency function block 317 acquisition reduction frequency sine sequence of function is formula (28):
In one embodiment, reducing frequency function block 317 acquisition reduction frequency cosine function sequence is formula (29):
In formula, X
sin+fn () is for reducing the frequency sine sequence of function, X
cos+fn (), for reducing frequency cosine function sequence, sequence frequency reduces Ω
set.
In one embodiment, reducing frequency orthogonal block 318 acquisition reduction frequency orthogonal sequence is formula (30):
In formula, sequence X
sin+f(n) and sequence X
cos+fn () is orthogonal each other.
Each technical characteristic of the above embodiment can combine arbitrarily, for making description succinct, the all possible combination of each technical characteristic in above-described embodiment is not all described, but, as long as the combination of these technical characteristics does not exist contradiction, be all considered to be the scope that this instructions is recorded.
The above embodiment only have expressed several embodiment of the present invention, and it describes comparatively concrete and detailed, but can not therefore be construed as limiting the scope of the patent.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be as the criterion with claims.
Claims (10)
1. obtain a method for the reduction frequency orthogonal sequence of electric power signal, it is characterized in that, comprise the following steps:
According to the lower limit of frequency power signal scope, default sample frequency and default integer signal period number, obtain the preliminary sequence length of described electric power signal;
According to described preliminary sequence length, described electric power signal is sampled, obtain the preliminary sequence of described electric power signal;
Frequency preliminary survey is carried out to described preliminary sequence, generates the first synchronizing frequency of described electric power signal, and according to described preliminary frequency setting the reference frequency of electric power signal;
According to described default sample frequency and described reference frequency, obtain the unit period sequence length of described electric power signal;
According to described default integer signal period number and described unit period sequence length, obtain the predetermined sequence length of described electric power signal;
According to default starting point and described predetermined sequence length, from described preliminary sequence, obtain the first forward sequence of described electric power signal;
The first anti-pleat sequence of described electric power signal is obtained according to described first forward sequence;
Obtain the first positive phase of described electric power signal according to described first forward sequence, and obtain the first antiphase of described electric power signal according to described first anti-pleat sequence;
The first average initial phase of described electric power signal is obtained according to described first positive phase and described first antiphase;
Described first average initial phase and ± π/4 are compared, obtains the first phase compare value compared with described ± π/4, and according to described first phase compare value and described default starting point, obtain new starting point;
According to described new starting point and described predetermined sequence length, from described preliminary sequence, obtain the sequence of forward again of described electric power signal, and obtain the again anti-pleat sequence of described electric power signal according to the described sequence of forward again;
Obtain the positive phase again of described electric power signal according to the described sequence of forward again, and obtain the antiphase again of described electric power signal according to described anti-pleat sequence again;
The again average initial phase of described electric power signal is obtained according to described positive phase again and described antiphase again;
The described sequence of forward again and described anti-pleat sequence are again added, and according to the result after addition and described average initial phase again, obtain the cosine function modulation sequence of described electric power signal;
The described sequence of forward again and described anti-pleat sequence are again subtracted each other, and according to the result after subtracting each other and described average initial phase again, obtains the sine function modulation sequence of described electric power signal;
The discrete sine function of default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the first multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described sine function modulation sequence and obtains the second multiplication sequence of described electric power signal, the discrete sine function of default fine setting frequency is multiplied with described sine function modulation sequence and obtains the 3rd multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the 4th multiplication sequence of described electric power signal,
Described second multiplication sequence and described first multiplication sequence are subtracted each other, obtains the reduction frequency sine sequence of function of described electric power signal; Described 4th multiplication sequence is added with described 3rd multiplication sequence, obtains the reduction frequency cosine function sequence of described electric power signal;
The reduction frequency orthogonal sequence of described electric power signal is obtained according to the described reduction frequency sine sequence of function and described reduction frequency cosine function sequence.
2. the method for the reduction frequency orthogonal sequence of acquisition electric power signal according to claim 1, is characterized in that, described electric power signal is the cosine function signal of single fundamental frequency, according to expression formula
obtain described preliminary sequence X
start(n), wherein
n=0,1,2,3 ..., N
start-1, A is signal amplitude, ω
ifor signal frequency,
for the initial phase of described preliminary sequence, T is sampling interval duration, and f is described default sample frequency, and n is series of discrete number, N
startfor described preliminary sequence length.
3. the method for the reduction frequency orthogonal sequence of acquisition electric power signal according to claim 2, is characterized in that, according to expression formula
obtain described cosine function modulation sequence X
cos(n), wherein n=0,1,2 ..., N-1, X
+ endn () is the described sequence of forward again, X
-end(-n) is described anti-pleat sequence again, PH
end-avgfor described average initial phase again, n is series of discrete number, and N is described predetermined sequence length.
4. the method for the reduction frequency orthogonal sequence of the acquisition electric power signal according to Claims 2 or 3, is characterized in that, according to expression formula
obtain described sine function modulation sequence X
sin(n), wherein n=0,1,2 ..., N-1, X
+ endn () is the described sequence of forward again, X
-end(-n) is described anti-pleat sequence again, PH
end-avgfor described average initial phase again, n is series of discrete number, and N is described predetermined sequence length.
5. the method for the reduction frequency orthogonal sequence of acquisition electric power signal according to claim 1, is characterized in that, according to expression formula X1 (n)=X
cos(n) sin (Ω
settn) described first multiplication sequence X1 (n) is obtained, according to expression formula X2 (n)=X
sin(n) cos (Ω
settn) described second multiplication sequence X2 (n) is obtained, according to expression formula X3 (n)=X
sin(n) sin (Ω
settn) described 3rd multiplication sequence X3 (n) is obtained, according to expression formula X4 (n)=X
cos(n) cos (Ω
settn) described 4th multiplication sequence X4 (n), wherein n=0 is obtained, 1,2 ..., N-1, X
cosn () is described cosine function modulation sequence, X
sinn () is described sine function modulation sequence, sin (Ω
settn) be the discrete sine function of described default fine setting frequency, cos (Ω
settn) be the discrete cosine function of described default fine setting frequency, Ω
setfor described default fine setting frequency, T is sampling interval duration, and n is series of discrete number, and N is described predetermined sequence length.
6. obtain a system for the reduction frequency orthogonal sequence of electric power signal, it is characterized in that, comprising:
Preliminary sequence length modules, for the lower limit according to frequency power signal scope, presets sample frequency and default integer signal period number, obtains the preliminary sequence length of described electric power signal;
Preliminary sequence module, for sampling to described electric power signal according to described preliminary sequence length, obtains the preliminary sequence of described electric power signal;
Frequency preliminary survey module, for carrying out frequency preliminary survey to described preliminary sequence, generates the first synchronizing frequency of described electric power signal, and according to described preliminary frequency setting the reference frequency of electric power signal;
Unit period sequence length module, for according to described default sample frequency and described reference frequency, obtains the unit period sequence length of described electric power signal;
Predetermined sequence length modules, for according to described default integer signal period number and described unit period sequence length, obtains the predetermined sequence length of described electric power signal;
First forward block, for according to presetting starting point and described predetermined sequence length, obtains the first forward sequence of described electric power signal from described preliminary sequence;
First anti-pleat block, for obtaining the first anti-pleat sequence of described electric power signal according to described first forward sequence;
First phase module, for obtaining the first positive phase of described electric power signal according to described first forward sequence, and obtains the first antiphase of described electric power signal according to described first anti-pleat sequence;
First average initial phase module, for obtaining the first average initial phase of described electric power signal according to described first positive phase and described first antiphase;
Phase compare module, for described first average initial phase and ± π/4 being compared, obtaining the first phase compare value compared with described ± π/4, and according to described first phase compare value and described default starting point, obtaining new starting point;
Block again, for according to described new starting point and described predetermined sequence length, obtains the sequence of forward again of described electric power signal, and obtains the again anti-pleat sequence of described electric power signal according to the described sequence of forward again from described preliminary sequence;
Phase module again, for obtaining the positive phase again of described electric power signal according to the described sequence of forward again, and obtains the antiphase again of described electric power signal according to described anti-pleat sequence again;
Average initial phase module again, for obtaining the again average initial phase of described electric power signal according to described positive phase again and described antiphase again;
Cosine function modulation sequence module, for the described sequence of forward again and described anti-pleat sequence being again added, and according to the result after addition and described average initial phase again, obtains the cosine function modulation sequence of described electric power signal;
Sine function modulation sequence module, for the described sequence of forward again and described anti-pleat sequence again being subtracted each other, and according to the result after subtracting each other and described average initial phase again, obtains the sine function modulation sequence of described electric power signal;
Multiplication sequence module, the first multiplication sequence of described electric power signal is obtained for the discrete sine function of default fine setting frequency being multiplied with described cosine function modulation sequence, the discrete cosine function of described default fine setting frequency is multiplied with described sine function modulation sequence and obtains the second multiplication sequence of described electric power signal, the discrete sine function of default fine setting frequency is multiplied with described sine function modulation sequence and obtains the 3rd multiplication sequence of described electric power signal, the discrete cosine function of described default fine setting frequency is multiplied with described cosine function modulation sequence and obtains the 4th multiplication sequence of described electric power signal,
Reducing frequency function block, for described second multiplication sequence and described first multiplication sequence being subtracted each other, obtaining the reduction frequency sine sequence of function of described electric power signal; Described 4th multiplication sequence is added with described 3rd multiplication sequence, obtains the reduction frequency cosine function sequence of described electric power signal;
Reduce frequency orthogonal block, for obtaining the reduction frequency orthogonal sequence of described electric power signal according to the described reduction frequency sine sequence of function and described reduction frequency cosine function sequence.
7. the system of the reduction frequency orthogonal sequence of acquisition electric power signal according to claim 6, is characterized in that, described electric power signal is the cosine function signal of single fundamental frequency, and described preliminary sequence module is according to expression formula
obtain described preliminary sequence X
start(n), wherein
n=0,1,2,3 ..., N
start-1, A is signal amplitude, ω
ifor signal frequency,
for the initial phase of described preliminary sequence, T is sampling interval duration, and f is described default sample frequency, and n is series of discrete number, N
startfor described preliminary sequence length.
8. the system of the reduction frequency orthogonal sequence of acquisition electric power signal according to claim 7, is characterized in that, described cosine function modulation sequence module is according to expression formula
obtain described cosine function modulation sequence X
cos(n), wherein n=0,1,2 ..., N-1, X
+ endn () is the described sequence of forward again, X
-end(-n) is described anti-pleat sequence again, PH
end-avgfor described average initial phase again, n is series of discrete number, and N is described predetermined sequence length.
9. the system of the reduction frequency orthogonal sequence of the acquisition electric power signal according to claim 7 or 8, is characterized in that, described sine function modulation sequence module is according to expression formula
obtain described sine function modulation sequence X
sin(n), wherein n=0,1,2 ..., N-1, X
+ endn () is the described sequence of forward again, X
-end(-n) is described anti-pleat sequence again, PH
end-avgfor described average initial phase again, n is series of discrete number, and N is described predetermined sequence length.
10. the system of the reduction frequency orthogonal sequence of acquisition electric power signal according to claim 6, is characterized in that, described multiplication sequence module is according to expression formula X1 (n)=X
cos(n) sin (Ω
settn) described first multiplication sequence X1 (n) is obtained, according to expression formula X2 (n)=X
sin(n) cos (Ω
settn) described second multiplication sequence X2 (n) is obtained, according to expression formula X3 (n)=X
sin(n) sin (Ω
settn) described 3rd multiplication sequence X3 (n) is obtained, according to expression formula X4 (n)=X
cos(n) cos (Ω
settn) described 4th multiplication sequence X4 (n), wherein n=0 is obtained, 1,2 ..., N-1, X
cosn () is described cosine function modulation sequence, X
sinn () is described sine function modulation sequence, sin (Ω
settn) be the discrete sine function of described default fine setting frequency, cos (Ω
settn) be the discrete cosine function of described default fine setting frequency, Ω
setfor described default fine setting frequency, T is sampling interval duration, and n is series of discrete number, and N is described predetermined sequence length.
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Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3441871A (en) * | 1967-01-05 | 1969-04-29 | Gen Electric Co Ltd | Oscillator system selectively operable as frequency measuring device or automatic frequency control |
US3675124A (en) * | 1970-10-28 | 1972-07-04 | Sperry Rand Corp | Apparatus for measuring frequency modulation noise signals and for calibrating same |
DE3327876A1 (en) * | 1982-08-02 | 1984-03-01 | Raytheon Co., 02173 Lexington, Mass. | FREQUENCY MEASURING DEVICE |
JP2015025726A (en) * | 2013-07-26 | 2015-02-05 | 東芝三菱電機産業システム株式会社 | Frequency detecting device, frequency detecting method, and electric power converter |
CN104502706A (en) * | 2014-12-29 | 2015-04-08 | 广东电网有限责任公司电力科学研究院 | Harmonic amplitude measurement method and system of power signal |
CN104502700A (en) * | 2014-12-29 | 2015-04-08 | 广东电网有限责任公司电力科学研究院 | Sinusoidal parameter measurement method and system of power signal |
CN104635044A (en) * | 2015-02-05 | 2015-05-20 | 广东电网有限责任公司电力科学研究院 | Power signal frequency detection method and system based on amplitude modulation |
CN104635045A (en) * | 2015-02-05 | 2015-05-20 | 广东电网有限责任公司电力科学研究院 | Power signal frequency detection method and system based on phase modulation |
CN105067880A (en) * | 2015-09-18 | 2015-11-18 | 广东电网有限责任公司电力科学研究院 | Method and system for orthogonal modulation of power signals |
-
2015
- 2015-12-04 CN CN201510891240.XA patent/CN105548701B/en active Active
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3441871A (en) * | 1967-01-05 | 1969-04-29 | Gen Electric Co Ltd | Oscillator system selectively operable as frequency measuring device or automatic frequency control |
US3675124A (en) * | 1970-10-28 | 1972-07-04 | Sperry Rand Corp | Apparatus for measuring frequency modulation noise signals and for calibrating same |
DE3327876A1 (en) * | 1982-08-02 | 1984-03-01 | Raytheon Co., 02173 Lexington, Mass. | FREQUENCY MEASURING DEVICE |
JP2015025726A (en) * | 2013-07-26 | 2015-02-05 | 東芝三菱電機産業システム株式会社 | Frequency detecting device, frequency detecting method, and electric power converter |
CN104502706A (en) * | 2014-12-29 | 2015-04-08 | 广东电网有限责任公司电力科学研究院 | Harmonic amplitude measurement method and system of power signal |
CN104502700A (en) * | 2014-12-29 | 2015-04-08 | 广东电网有限责任公司电力科学研究院 | Sinusoidal parameter measurement method and system of power signal |
CN104635044A (en) * | 2015-02-05 | 2015-05-20 | 广东电网有限责任公司电力科学研究院 | Power signal frequency detection method and system based on amplitude modulation |
CN104635045A (en) * | 2015-02-05 | 2015-05-20 | 广东电网有限责任公司电力科学研究院 | Power signal frequency detection method and system based on phase modulation |
CN105067880A (en) * | 2015-09-18 | 2015-11-18 | 广东电网有限责任公司电力科学研究院 | Method and system for orthogonal modulation of power signals |
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