CN105425040B - Based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system - Google Patents

Based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system Download PDF

Info

Publication number
CN105425040B
CN105425040B CN201510890785.9A CN201510890785A CN105425040B CN 105425040 B CN105425040 B CN 105425040B CN 201510890785 A CN201510890785 A CN 201510890785A CN 105425040 B CN105425040 B CN 105425040B
Authority
CN
China
Prior art keywords
sequence
frequency
initial phase
cosine function
phase
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201510890785.9A
Other languages
Chinese (zh)
Other versions
CN105425040A (en
Inventor
李军
陈世和
万文军
王越超
李晓枫
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Electric Power Research Institute of Guangdong Power Grid Co Ltd
Original Assignee
Electric Power Research Institute of Guangdong Power Grid Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Electric Power Research Institute of Guangdong Power Grid Co Ltd filed Critical Electric Power Research Institute of Guangdong Power Grid Co Ltd
Priority to CN201510890785.9A priority Critical patent/CN105425040B/en
Publication of CN105425040A publication Critical patent/CN105425040A/en
Application granted granted Critical
Publication of CN105425040B publication Critical patent/CN105425040B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Measuring Frequencies, Analyzing Spectra (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)

Abstract

The present invention relates to one kind to be based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system, obtain real frequency mixing sequence and empty frequency is mixed sequence, then digital filtering and integration are carried out to the real frequency mixing sequence and the empty frequency mixing sequence, obtain real frequency integrated value and empty frequency integrated value, according to the real frequency integrated value and empty frequency integrated value, the phase of zero initial phase benchmark cosine function times frequency sequence is obtained, the frequency of electric power signal is obtained according to the phase.The frequency of electric power signal is obtained by mode of the present invention, is remarkably improved the degree of accuracy of frequency power signal measurement.

Description

Based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system
Technical field
The present invention relates to technical field of power systems, and zero initial phase benchmark cosine function frequency multiplication is based on more particularly to one kind Sequence frequency measuring method and system.
Background technology
The frequency measurement of power system, phase measurement, amplitude measurement etc. are the measurement of sine parameter in itself.Fu Li Leaf transformation is the basic skills for realizing sine parameter measurement, is widely used in power system.But as sine parameter is surveyed The development of amount technology, the problem of Fourier transformation is present also more aobvious protrusion, it is difficult to further meet that sine is joined in power system The requirement that number high accuracy calculates.
In terms of power system sine parameter measurement, there are some improved measurement method of parameters, such as zero hands over method, based on filter The mensuration of ripple, the mensuration based on Wavelet Transform, based on neutral net, based on DFT (Discrete Fourier Transform, discrete Fourier transform) conversion mensuration etc..Because the specified power frequency of operation of power networks is near 50Hz (hertz), Belong to the relatively low sinusoidal frequency of frequency, and interference in the electric power signal of reality be present, such as harmonic wave interference, electric load are small In the range of similar white noise acoustic jamming etc. caused by random fluctuation, under interference environment, the measurement of these algorithm generally existings is accurate The problem of degree is not high.
The content of the invention
Based on this, it is necessary in view of the above-mentioned problems, providing a kind of based on zero initial phase benchmark cosine function times frequency sequence frequency Rate measuring method and system, it is possible to increase the degree of accuracy of frequency power signal measurement.
In order to solve the above technical problems, the present invention adopts the following technical scheme that:
A kind of frequency measurement method based on zero initial phase benchmark cosine function times frequency sequence, including step:
According to the lower limit of frequency power signal scope, preset sample frequency and default integer signal period number, obtain preliminary Sequence length;
Electric power signal is sampled according to the preliminary sequence length, obtains the preliminary sequence of the electric power signal;
Line frequency preliminary survey is entered to the preliminary sequence, obtains the preliminary frequency of the electric power signal, according to the just cadence Rate obtains reference frequency;
According to the preset sample frequency and the reference frequency, the unit period sequence for obtaining the electric power signal is grown Degree;
The default integer signal period number is multiplied with the unit period sequence length, obtains preprocessing sequence length Degree;
According to the preprocessing sequence length, preprocessing sequence is obtained from the preliminary sequence of the electric power signal;
Comb filtering processing is carried out to the preprocessing sequence, obtains comb filtering sequence, wherein comb filtering sequence is grown Spend the residue length after comb filtering processing is carried out for the preprocessing sequence;
The ratio integer of the comb filtering sequence length and the unit period sequence length is determined, according to the ratio Integer and the unit period sequence length obtain predetermined sequence length, wherein the ratio integer is odd number, the default sequence Row length is odd number;
According to the predetermined sequence length and default starting point, the first positive sequence is obtained from the comb filtering sequence Row, the first anti-pleat sequence is obtained according to the described first positive sequence;
First positive phase is obtained according to the described first positive sequence, it is anti-phase to obtain first according to the described first anti-pleat sequence Position;
First average initial phase is obtained according to first positive phase and first antiphase;
According to the described first average initial phase and preset phase value, obtain phase fiducial value, according to the phase fiducial value, The default starting point and the unit period sequence length, obtain new starting point;
According to the predetermined sequence length and the new starting point, the second positive sequence is obtained from the comb filtering sequence Row, the second anti-pleat sequence is obtained according to the second positive sequence;
Second positive phase is obtained according to the described second positive sequence, it is anti-phase to obtain second according to the described second anti-pleat sequence Position;
Second average initial phase is obtained according to second positive phase and second antiphase;
Described second positive sequence is added with the described second anti-pleat sequence, obtained and sequence, according to described and sequence and The cosine function value of described second average initial phase, obtains cosine function modulation sequence;
Described second positive sequence and the described second anti-pleat sequence are subtracted each other, obtain difference sequence, according to the difference sequence and The sine function of described second average initial phase, obtains SIN function modulation sequence;
Exported from the cosine function modulation sequence central point, obtain zero initial phase benchmark cosine function modulation sequence, from The SIN function modulation sequence central point output, obtains zero initial phase reference sinusoidal FUNCTION MODULATION sequence;
By the zero initial phase benchmark cosine function modulation sequence square with the zero initial phase reference sinusoidal function adjust Sequence processed square is subtracted each other, and obtains zero initial phase benchmark cosine function times frequency sequence;
Discrete cosine function of the zero initial phase benchmark cosine function times frequency sequence respectively with 2 times of reference frequencies is multiplied It is multiplied with the discrete sine function of 2 times of reference frequencies, obtains real frequency mixing sequence and empty frequency is mixed sequence;
Digital filtering is carried out to the real frequency mixing sequence and the empty frequency mixing sequence respectively, obtains real frequency filtered sequence With imaginary frequency filtering sequence;
The real frequency filtered sequence and the imaginary frequency filtering sequence are integrated respectively, obtain real frequency integrated value and empty frequency Integrated value;
According to the real frequency integrated value and empty frequency integrated value, the phase of zero initial phase benchmark cosine function times frequency sequence of acquisition Position, the frequency of electric power signal is obtained according to the phase.
A kind of frequency measuring system based on zero initial phase benchmark cosine function times frequency sequence, including:
Preliminary sequence length determination modul, for the lower limit according to frequency power signal scope, preset sample frequency and pre- If integer signal period number, preliminary sequence length is obtained;
Preliminary sequence acquisition module, for being sampled according to the preliminary sequence length to electric power signal, described in acquisition The preliminary sequence of electric power signal;
Reference frequency determining module, for entering line frequency preliminary survey to the preliminary sequence, obtain the first of the electric power signal Synchronizing frequency, reference frequency is obtained according to the preliminary frequency;
Unit period sequence length determining module, for according to the preset sample frequency and the reference frequency, obtaining The unit period sequence length of the electric power signal;
Preprocessing sequence length determination modul, for by the default integer signal period number and the unit period sequence Length is multiplied, and obtains preprocessing sequence length;
Preprocessing sequence acquisition module, for according to the preprocessing sequence length, from the preliminary sequence of the electric power signal Preprocessing sequence is obtained in row;
Comb filtering sequence determining module, for carrying out comb filtering processing to the preprocessing sequence, obtain pectination filter Wave train, wherein comb filtering sequence length are residue length of the preprocessing sequence after comb filtering processing is carried out;
Predetermined sequence length determination modul, for determining that the comb filtering sequence length is grown with the unit period sequence The ratio integer of degree, predetermined sequence length is obtained according to the ratio integer and the unit period sequence length, wherein described Ratio integer is odd number, and the predetermined sequence length is odd number;
First ray acquisition module, for according to the predetermined sequence length and default starting point, from the comb filtering The first positive sequence is obtained in sequence, the first anti-pleat sequence is obtained according to the described first positive sequence;
First positive and negative phase determination module, for obtaining the first positive phase according to the described first positive sequence, according to described First anti-pleat sequence obtains the first antiphase;
First average initial phase determining module, for obtaining first according to first positive phase and first antiphase Average initial phase;
New starting point determining module, for according to the described first average initial phase and preset phase value, obtaining phase bit comparison Value, according to the phase fiducial value, the default starting point and the unit period sequence length, obtains new starting point;
Second retrieval module, for according to the predetermined sequence length and the new starting point, being filtered from the pectination The second positive sequence is obtained in wave train, the second anti-pleat sequence is obtained according to the second positive sequence;
Second positive and negative phase determination module, for obtaining the second positive phase according to the described second positive sequence, according to described Second anti-pleat sequence obtains the second antiphase;
Second average initial phase determining module, for obtaining second according to second positive phase and second antiphase Average initial phase;
Cosine function modulation sequence determining module, for by the described second positive sequence and the described second anti-pleat sequence phase Add, obtain and sequence, the cosine function value for the initial phase that is averaged according to described and sequence and described second, acquisition cosine function are modulated Sequence;
SIN function modulation sequence determining module, for by the described second positive sequence and the described second anti-pleat sequence phase Subtract, obtain difference sequence, according to the difference sequence and the sine function of the second average initial phase, obtain SIN function modulation Sequence;
Zero initial phase modulation sequence acquisition module, for being exported from the cosine function modulation sequence central point, obtain zero Initial phase benchmark cosine function modulation sequence, exported from the SIN function modulation sequence central point, obtain zero initial phase benchmark SIN function modulation sequence;
Zero initial phase benchmark cosine function times frequency sequence determines sequence, for the zero initial phase benchmark cosine function to be adjusted Square square subtracting each other with the zero initial phase reference sinusoidal FUNCTION MODULATION sequence for sequence processed, obtains zero initial phase benchmark cosine Function times frequency sequence;
Sequence determining module is mixed, for the zero initial phase benchmark cosine function times frequency sequence to be referred to 2 times respectively The discrete cosine function of frequency is multiplied and is multiplied with the discrete sine function of 2 times of reference frequencies, obtains real frequency mixing sequence and empty frequency It is mixed sequence;
Filtered sequence determining module, for carrying out numeral to the real frequency mixing sequence and the empty frequency mixing sequence respectively Filtering, obtains real frequency filtered sequence and imaginary frequency filtering sequence;
Integrated value determining module, for being integrated respectively to the real frequency filtered sequence and the imaginary frequency filtering sequence, Obtain real frequency integrated value and empty frequency integrated value;
Frequency power signal determining module, for according to the real frequency integrated value and empty frequency integrated value, obtaining zero initial phase The phase of benchmark cosine function times frequency sequence, the frequency of electric power signal is obtained according to the phase.
The present invention is based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system, obtains real frequency and is mixed Sequence and empty frequency are mixed sequence, then carry out digital filtering and product to the real frequency mixing sequence and the empty frequency mixing sequence Point, real frequency integrated value and empty frequency integrated value are obtained, according to the real frequency integrated value and empty frequency integrated value, obtains zero initial phase benchmark The phase of cosine function times frequency sequence, the frequency of electric power signal is obtained according to the phase.Electric power is obtained by mode of the present invention The frequency of signal, it is remarkably improved the degree of accuracy of frequency power signal measurement.
Brief description of the drawings
Fig. 1 is that the flow of the invention based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method embodiment is shown It is intended to;
Fig. 2 is schematic diagram of the comb filtering of the present invention processing in frequency domain amplitude versus frequency characte;
Fig. 3 is comb filtering sequence of the present invention, the first positive sequence, the schematic diagram of the first anti-pleat sequence;
Fig. 4 is the pictorial diagram of zero initial phase datum mark of the invention;
Fig. 5 is that the structure of the invention based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring system embodiment is shown It is intended to.
Embodiment
It is below in conjunction with the accompanying drawings and preferably real further to illustrate the effect of the technological means of the invention taken and acquirement Example is applied, to technical scheme, carries out clear and complete description.
As shown in figure 1, a kind of be based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method, including step:
S101, according to the lower limit of frequency power signal scope, preset sample frequency and default integer signal period number, obtain Preliminary sequence length;
S102, according to the preliminary sequence length electric power signal is sampled, obtain the preliminary sequence of the electric power signal Row;
S103, line frequency preliminary survey is entered to the preliminary sequence, obtain the preliminary frequency of the electric power signal, according to described first Synchronizing frequency obtains reference frequency;
S104, according to the preset sample frequency and the reference frequency, obtain the unit period sequence of the electric power signal Row length;
S105, the default integer signal period number is multiplied with the unit period sequence length, obtains pretreatment sequence Row length;
S106, according to the preprocessing sequence length, obtain preprocessing sequence from the preliminary sequence of the electric power signal;
S107, comb filtering processing is carried out to the preprocessing sequence, obtain comb filtering sequence, wherein comb filtering sequence Row length is residue length of the preprocessing sequence after comb filtering processing is carried out;
S108, the ratio integer for determining the comb filtering sequence length and the unit period sequence length, according to institute State ratio integer and the unit period sequence length obtains predetermined sequence length, wherein the ratio integer is odd number, it is described Predetermined sequence length is odd number;
S109, according to the predetermined sequence length and default starting point, obtaining first just from the comb filtering sequence To sequence, the first anti-pleat sequence is obtained according to the described first positive sequence;
S110, the first positive phase obtained according to the described first positive sequence, first is obtained according to the described first anti-pleat sequence Antiphase;
S111, the first average initial phase is obtained according to first positive phase and first antiphase;
S112, be averaged initial phase and preset phase value according to described first, phase fiducial value is obtained, according to the phase ratio Compared with value, the default starting point and the unit period sequence length, new starting point is obtained;
S113, according to the predetermined sequence length and the new starting point, obtain second from the comb filtering sequence Positive sequence, the second anti-pleat sequence is obtained according to the second positive sequence;
S114, the second positive phase obtained according to the described second positive sequence, second is obtained according to the described second anti-pleat sequence Antiphase;
S115, the second average initial phase is obtained according to second positive phase and second antiphase;
S116, the described second positive sequence is added with the described second anti-pleat sequence, obtained and sequence, according to described and sequence The cosine function value of row and the described second average initial phase, obtains cosine function modulation sequence;
S117, the described second positive sequence and the described second anti-pleat sequence subtracted each other, difference sequence is obtained, according to the poor sequence The sine function of row and the described second average initial phase, obtains SIN function modulation sequence;
S118, from the cosine function modulation sequence central point export, obtain zero initial phase benchmark cosine function modulation sequence Row, exported from the SIN function modulation sequence central point, obtain zero initial phase reference sinusoidal FUNCTION MODULATION sequence;
S119, by the zero initial phase benchmark cosine function modulation sequence square with the zero initial phase reference sinusoidal letter Number modulation sequences square subtract each other, and obtain zero initial phase benchmark cosine function times frequency sequence;
S120, by the zero initial phase benchmark cosine function times frequency sequence discrete cosine letter with 2 times of reference frequencies respectively Number is multiplied and is multiplied with the discrete sine function of 2 times of reference frequencies, obtains real frequency mixing sequence and empty frequency is mixed sequence;
S121, digital filtering is carried out to the real frequency mixing sequence and the empty frequency mixing sequence respectively, obtain real frequency and filter Wave train and imaginary frequency filtering sequence;
S122, the real frequency filtered sequence and the imaginary frequency filtering sequence are integrated respectively, obtain real frequency integrated value With empty frequency integrated value;
S123, according to the real frequency integrated value and empty frequency integrated value, obtain zero initial phase benchmark cosine function times frequency sequence Phase, according to the phase obtain electric power signal frequency.
Actual electric power signal is a kind of sinusoidal signal based on fundamental wave component, and unless otherwise specified, electric power signal refers both to Fundamental signal, frequency power signal refer both to fundamental frequency.For step S101, power system frequency scope is typically (conspicuous in 45Hz Hereby) -55Hz, so the lower limit f of frequency power signal scopemin45Hz can be taken as.Default integer signal period number CCan root Set according to being actually needed, for example, by CIt is taken as 17.Preliminary sequence length can calculate according to formula (1):
Wherein, NstartFor preliminary sequence length;(int) represent to round;CTo preset integer signal period number;fminFor electricity The lower limit of force signal frequency range, unit Hz;F is preset sample frequency, unit Hz.
For step S102, the cosine function signal representation electric power signal of single fundamental frequency can be used, then preliminary sequence For formula (2):
Wherein, Xstart(n) it is preliminary sequence;A is signal amplitude, unit v;ωiFor signal frequency, when T is the sampling interval Between, f is preset sample frequency, and unit Hz, n are series of discrete number,For the initial phase of preliminary sequence, NstartGrown for preliminary sequence Degree.
For step S103, can by zero hand over method, the algorithm based on filtering, based on Wavelet Transformation Algorithm, based on nerve net The algorithm of network, the frequency algorithm based on DFT transform enter line frequency preliminary survey to preliminary sequence based on the frequency algorithm of phase difference, obtain Take preliminary frequency ωo.In one embodiment, the reference frequency ωso
For step S104, in one embodiment, the unit period sequence length of the electric power signal calculates, and is formula (3):
Wherein, NFor unit periodic sequence length;(int) it is round numbers;F is preset sample frequency, unit Hz;ωsFor Reference frequency.The error in 1 sampling interval be present in the unit period sequence length integer.
For step S105, the preprocessing sequence length is formula (4):
Nset=CN (4)
Wherein, NsetFor preprocessing sequence length;CTo preset integer signal period number;NGrown for unit periodic sequence Degree.
For step S106, in one embodiment, preprocessing sequence is obtained, is formula (5):
Wherein, Xset(n) it is preprocessing sequence, Xstart(n) it is preliminary sequence, NsetFor preprocessing sequence length.
Subharmonic, even-order harmonic, odd harmonic etc. in electric power signal be present, in optical mixing process, caused mixing Interfering frequency has a strong impact on the accuracy in computation of sine parameter, and carrying out comb filtering processing can be from source to mixing interfering frequency production Raw factor is effectively suppressed.
For step S107,2 different list entries of starting point are subtracted each other, the frequency domain amplitude-frequency filtering that can obtain pectination is special Property, referred to as comb filtering is handled.The interval of 2 list entries is defined as comb filtering parameter, the processing of single-stage comb filtering It is expressed as formula (6):
Wherein, XL(n) it is single-stage comb filtering output sequence;Xset(n) it is preprocessing sequence;Xset(NL+ n) it is from NLRise The preprocessing sequence of beginning;NLFor 2 train intervals or single-stage comb filtering parameter;NsetFor preprocessing sequence length;NFor unit Periodic sequence length.Comb filtering parameter NLValue is unit periodic sequence length N0.5 times, even-order harmonic can be carried out Suppress and subharmonic is decayed.
In one embodiment, comb filtering processing can be carried out to the preprocessing sequence by comb filter.By In reference frequency has error, comb filtering parameter has integer error, in order to improve comb-filter effects, 8 can be passed through Level comb filter carries out comb filtering processing, is expressed as formula (7):
Wherein, X8L(n) it is 8 grades of comb filter or comb filtering sequence;Filter[8,NL,Xset(n) 8 represent comb in] Shape filtering series is 8, NLFor single-stage comb filtering parameter, Xset(n) it is preprocessing sequence;KLi) exist for comb filtering processing Signal frequency ωiDimensionless amplitude gain, T is sampling interval duration;For comb filtering sequence initial phase;NsetFor pre- place Manage sequence length.
Comb filtering processing needs to use unit period sequence length N4 times of sequence lengths.Comb filtering processing is in frequency Domain amplitude versus frequency characte is as shown in Figure 2.
For step S108, in one embodiment, ratio integer is set to odd number, determines the comb filtering sequence length It is formula (8) with the ratio integer of the unit period sequence length:
Wherein, k is the ratio integer, NsetFor preprocessing sequence length, NLFor single-stage comb filtering parameter, NFor list Bit period sequence length.
In one embodiment, predetermined sequence length is arranged to odd number, and predetermined sequence length computation is formula (9):
Wherein, N is predetermined sequence length, and k is the ratio integer, NFor unit periodic sequence length.
For step S109, in one embodiment, default starting point can be the 0.5 of the unit period sequence length Times, the first positive sequence, it is formula (10):
Wherein, X8L(n) it is 8 grades of comb filtering sequences, X+start(n) it is the first positive sequence, PstartTo preset starting point, NFor unit periodic sequence length, (int) is round numbers, and A is signal amplitude, unit v, ωiFor signal frequency, KLi) it is comb Shape filtering process is in signal frequency ωiDimensionless amplitude gain, T is sampling interval duration, and n is series of discrete number,For One positive sequence initial phase, N are predetermined sequence length.
In one embodiment, the described first anti-pleat sequence is formula (11):
Wherein, X-start(- n) is the first anti-pleat sequence, X+start(n) it is the first positive sequence, A is signal amplitude, unit V, ωiFor signal frequency, T is sampling interval duration, and n is series of discrete number, and β 1 is the first anti-pleat sequence initial phase, and N is default Sequence length.Comb filtering sequence, the first positive sequence and the first anti-pleat sequence pattern expression are as shown in Figure 3.
For step S110, the calculating of the first positive phase and the first antiphase is the knot based on orthogonal mixing and integral and calculating Fruit.
When not considering the mixing interfering frequency of orthogonal mixing, orthogonal mixing is expressed as formula (12), and integral and calculating is expressed as Formula (13):
Wherein, R+start(n) it is the first positive real frequency mixing sequence, I+start(n) sequence, R are mixed for the first weakened body resistance frequency-start (- n) is that the first anti-real frequency is mixed sequence, I-start(- n) is that the first anti-empty frequency is mixed sequence, cos (ωs) or cos (- ω TnsTn) For the discrete cosine function of reference frequency, sin (ωs) or sin (- ω TnsTn) it is for the discrete sine function of reference frequency, Ω Signal frequency ωiWith reference frequency ωsFrequency difference, T is sampling interval duration, and n is series of discrete number, KLi) it is comb filtering Processing is in signal frequency ωiDimensionless amplitude gain,For the first positive sequence initial phase, β 1 is at the beginning of the first positive sequence Phase, N are predetermined sequence length.
Wherein, R+startFor the first just real frequency integrated value, unit dimensionless, I+startFor the first weakened body resistance frequency integrated value, unit Dimensionless, R-startFor the first anti-real frequency integrated value, unit dimensionless, I-startFor the first anti-empty frequency mixing integrated value, unit without Dimension, Ω are signal frequency ωiWith reference frequency ωsFrequency difference, T is sampling interval duration, and n is series of discrete number, and N is default Sequence length,For the first positive sequence initial phase, β 1 is the first anti-pleat sequence initial phase, and N is predetermined sequence length.
In one embodiment, the calculating of the first positive phase and the first antiphase, it is expressed as formula (14):
Wherein, PH+startFor the first positive phase, PH-startFor the first antiphase, R+startIt is single for the first just real frequency integrated value Position dimensionless, I+startFor the first weakened body resistance frequency integrated value, unit dimensionless, R-startIt is immeasurable for the first anti-real frequency integrated value, unit Guiding principle, I-startFor the first anti-empty frequency mixing integrated value, unit dimensionless, Ω is signal frequency ωiWith reference frequency ωsFrequency difference, T For sampling interval duration, N is predetermined sequence length,For the first positive sequence initial phase, β 1 is the first anti-pleat sequence first phase Position.
For step S111, in one embodiment, the first average initial phase computational methods, formula (15) is expressed as:
Wherein, PHstart-avgFor the first average initial phase, PH+startFor the first positive phase, PH-startFor the first antiphase,For the first positive sequence initial phase, β 1 is the first anti-pleat sequence initial phase.
For step S112, in one embodiment, the preset phase value can be ± π/4;It is flat according to described first Equal initial phase and preset phase value, the step of obtaining phase fiducial value, can include:
If the described first average initial phase is less than or equal to pi/2 more than or equal to 0, the described first average first phase is subtracted according to π/4 Position obtains phase fiducial value;
If the described first average initial phase is more than or equal to-pi/2 is less than or equal to 0, according to-π/4 subtract described first it is average just Phase obtains phase fiducial value.
Specially formula (16):
Wherein, △ PHcomFor phase fiducial value, unit rad, PHstart-avgFor the first average initial phase.
In one embodiment, the new starting point calculates, and is formula (17):
Wherein, PnewFor new starting point, unit dimensionless, PstartTo preset starting point, △ PHcomIt is single for phase fiducial value Position rad, NFor unit periodic sequence length, (int) is round numbers.
For step S113, the second positive sequence and the second anti-pleat sequence are formula (18):
Wherein, X8L(n) it is 8 grades of comb filtering sequences, X+end(n) it is the second positive sequence, X-end(- n) is the second anti-pleat Sequence, PnewFor new starting point, unit dimensionless, KLi) handled for comb filtering in signal frequency ωiDimensionless amplitude increase Benefit,For the second positive sequence initial phase, β 2 is the second anti-pleat sequence initial phase, ωiFor signal frequency, when T is the sampling interval Between, n is series of discrete number, and N is predetermined sequence length.
The computational methods of the second positive phase and the second antiphase, it is based on orthogonal mixing and numeral filter for step S114 The result that ripple calculates.The digital filtering is made up of 6 grades of rectangular window arithmetic mean filters of 2 kinds of filtering parameters.
When not considering the mixing interfering frequency of orthogonal mixing, orthogonal mixing is expressed as formula (19), and the 6 of 2 kinds of filtering parameters Level rectangular window arithmetic mean filter filtering calculation expression is formula (20):
Wherein, R+end(n) it is the second positive real frequency mixing sequence, I+end(n) sequence, R are mixed for the second weakened body resistance frequency-end(-n) For the second anti-real frequency mixing sequence, I-end(- n) is that the second anti-empty frequency is mixed sequence, cos (ωs) or cos (- ω TnsTn it is) ginseng Examine the discrete cosine function of frequency, sin (ωs) or sin (- ω TnsTn it is) discrete sine function of reference frequency, KLi) be Comb filtering processing is in signal frequency ωiDimensionless amplitude gain, Ω is signal frequency ωiWith reference frequency ωsFrequency difference, ωiFor signal frequency, T is sampling interval duration, and n is series of discrete number,For the first positive sequence initial phase, β 1 is first Anti- pleat sequence initial phase, N are predetermined sequence length.
Wherein, R+endFor the second just real frequency digital filtering final value, unit dimensionless;I+endFor the second weakened body resistance frequency digital filtering Final value, unit dimensionless;R-endFor the second anti-digital filtering final value, unit dimensionless;I-endIt is whole for the second anti-empty frequency digital filtering Value, unit dimensionless;KLi) handled for comb filtering in signal frequency ωiDimensionless amplitude gain, Ω is signal frequency ωiWith reference frequency ωsFrequency difference;K (Ω) is digital filtering in frequency difference Ω amplitude gain, unit dimensionless;T is between sampling Every the time;For the second positive sequence initial phase;β 2 is the second anti-pleat sequence initial phase;ND1For filtering parameter 1, i.e., to ND1It is individual Continuous centrifugal pump is added, and then takes its arithmetic mean of instantaneous value to be exported as this filter value;ND2For filtering parameter 2, i.e., to ND2Individual company Continuous centrifugal pump is added, and then takes its arithmetic mean of instantaneous value to be exported as this filter value;NDSequence length is used for digital filtering, number It is the summation of 6 grades of rectangular window arithmetic mean filter filtering parameters in amount, less than or equal to predetermined sequence length N.
In one embodiment, filtering parameter ND1Value is 1.5 times of the unit period sequence length of the reference frequency, Purpose carries out depth suppression to being mixed interfering frequency caused by 1/3 subharmonic;Filtering parameter ND2Value is the reference frequency 2 times of unit period sequence length, purpose carries out depth to being mixed interfering frequency caused by direct current, 1/2 gradation, subharmonic etc. Suppress.6 grades of rectangular window arithmetic mean filters filtering of 2 kinds of filtering parameters, which calculates, needs to use signal period sequence length 10.5 times.
Filtering parameter ND1With filtering parameter ND2It is calculated as formula (21):
Wherein, ND1For digital filter parameters 1, unit dimensionless, (int) is round numbers, ND2It is single for digital filter parameters 2 Position dimensionless, NFor unit periodic sequence length.
In one embodiment, the computational methods of the second positive phase and the second antiphase, it is expressed as formula (22):
Wherein, PH+endFor the second positive phase, PH-endFor the second antiphase, R+endFor the second just real frequency integrated value, unit without Dimension, I+endFor the second weakened body resistance frequency integrated value, unit dimensionless, R-endFor the second anti-real frequency integrated value, unit dimensionless, I-end For the second anti-empty frequency mixing integrated value, unit dimensionless, Ω is signal frequency ωiWith reference frequency ωsFrequency difference, T for sampling between Every the time, NDSequence length is used for digital filtering,For the second positive sequence initial phase, β 2 is the second anti-pleat sequence first phase Position.
For step S115, the second average initial phase computational methods, formula (23) is expressed as:
Wherein, PHend-avgFor the second average initial phase, PH+endFor the second positive phase, PH-endFor the second antiphase,For Second positive sequence initial phase, β 2 are the second positive sequence initial phase.
For step S116, cosine function modulation sequence is expressed as formula (24):
Wherein, Xcos(n) it is cosine function modulation sequence;A KLi) it is cosine function modulation sequence amplitude, unit v;For cosine function modulation sequence initial phase, KLi) handled for comb filtering in signal frequency ωiDimensionless Amplitude gain, ωiFor signal frequency, T is sampling interval duration, and n is series of discrete number, and N is predetermined sequence length,For Two positive sequence initial phases, β 2 are the second anti-pleat sequence initial phase.
For step S117, SIN function modulation sequence is expressed as formula (25):
Wherein, Xsin(n) it is SIN function modulation sequence, A KLi) it is SIN function modulation sequence amplitude, unit v,For cosine function modulation sequence initial phase, KLi) handled for comb filtering in signal frequency ωiDimensionless Amplitude gain, ωiSignal frequency, T are sampling interval duration, and n is series of discrete number, and N is predetermined sequence length,For second Positive sequence initial phase, β 2 are the second anti-pleat sequence initial phase.
For step S118, in one embodiment, zero initial phase benchmark cosine function modulation sequence is obtained, is expressed as formula (26):
Wherein, X0cos(n) it is zero initial phase benchmark cosine function modulation sequence, A KLi) it is cosine function modulation sequence Amplitude, unit v, ωiFor signal frequency, KLi) handled for comb filtering in signal frequency ωiDimensionless amplitude gain, T For sampling interval duration, n is series of discrete number, and N is predetermined sequence length.
In one embodiment, zero initial phase reference sinusoidal FUNCTION MODULATION sequence is obtained, is expressed as formula (27):
Wherein, X0sin(n) it is zero initial phase reference sinusoidal FUNCTION MODULATION sequence, A KLi) it is SIN function modulation sequence Amplitude, unit v, ωiFor signal frequency, KLi) handled for comb filtering in signal frequency ωiDimensionless amplitude gain, T is sampling interval duration, and n is series of discrete number, and (N-1)/2 are sequence length.Zero initial phase datum mark avatars such as Fig. 4 institutes Show.
For step S119, zero initial phase benchmark cosine function times frequency sequence is obtained, is expressed as formula (28):
Wherein, X02cos(n) it is zero initial phase benchmark cosine function times frequency sequence, U is public amplitude, unit v2, (N-1)/ 2 be sequence length.
For step S120, in one embodiment, obtain real frequency mixing sequence and empty frequency is mixed sequence, be expressed as formula (29):
Wherein, R (n) is mixed sequence for real frequency, and I (n) is mixed sequence, X02 for empty frequencycos(n) it is zero initial phase benchmark cosine Function times frequency sequence, cos (2 ωsTn it is) the discrete cosine function of 2 times of reference frequencies, sin (2 ωsTn) it is 2 times of reference frequencies Discrete sine function, U are public amplitude, unit v2, 2 Ω are 2 times of ω of signal frequency 2 of signaliWith 2 times of ω of reference frequency 2sFrequency Difference, T are sampling interval duration, and n is series of discrete number, and 0.5 (N-1) is mixing sequence length.Its middle frequency difference 2 Ω parts are useful The composition, (ω of frequency 2i+ωs) partly it is mixing interference component.
For step S121, the filtering series of digital filtering is set, in one embodiment, rectangular window arithmetic can be passed through Average value filtering algorithm carries out digital filtering to the real frequency mixing sequence and the empty frequency mixing sequence respectively.
In one embodiment, the filtering series of digital filtering could be arranged to 5 etc., and digital filter parameters are the unit cycle 1 times of sequence length, it is therefore an objective to which depth suppression is carried out to subharmonic mixing interfering frequency.Do not consider to be mixed interfering frequency, real frequency Filtered sequence and imaginary frequency filtering sequence are expressed as formula (30):
Wherein, RD(n) it is real frequency filtered sequence;ID(n) it is imaginary frequency filtering sequence;R (n) is mixed sequence for real frequency;I (n) is Empty frequency mixing sequence;U is public amplitude, unit v2;NDFor the filtering parameter of rectangular window arithmetic mean of instantaneous value filtering algorithm, i.e., to ND Individual continuous centrifugal pump is added, and then takes its arithmetic mean of instantaneous value to be exported as this filter value;T is sampling interval duration;NFor list Bit period sequence length;KD(2 Ω) is digital filtering in the Ω of frequency difference 2 amplitude gain, unit dimensionless;α (2 Ω) filters for numeral Phase shift of the ripple in the Ω of frequency difference 2;M is digital filtering output sequence length;0.5 (N-1) is digital filtering list entries length;N is Predetermined sequence length.
For step S122, in one embodiment, the digital filtering output sequence length is integration lengths, is obtained real Frequency integrated value and empty frequency integrated value, are expressed as formula (31):
Wherein, RDFor real frequency integrated value;IDFor empty frequency integrated value;RD(n) it is real frequency filtered sequence;ID(n) it is imaginary frequency filtering Sequence;T is sampling interval duration, and M is integration lengths;NDFor the filtering parameter of rectangular window arithmetic mean of instantaneous value filtering algorithm;0.5 (N-1) it is digital filtering list entries length;N is predetermined sequence length.
For step S123, in one embodiment, the phase of zero initial phase benchmark cosine function modulation sequence, table are obtained Up to for formula (32):
Wherein, PH is the phase of zero initial phase benchmark cosine function times frequency sequence, IDFor empty frequency integrated value, RDFor real frequency product Score value, M are integration lengths;NDFor the filtering parameter of rectangular window arithmetic mean of instantaneous value filtering algorithm.
In one embodiment, according to the phase of zero initial phase benchmark cosine function times frequency sequence, electric power signal frequency is obtained Rate, it is expressed as formula (33):
Wherein, ωiFor the frequency of electric power signal, PH is the phase of zero initial phase benchmark cosine function times frequency sequence, and T is to adopt Sample interval time, M are integration lengths, NDFor the filtering parameter of rectangular window arithmetic mean of instantaneous value filtering algorithm, ωsFor reference frequency.
Based on same inventive concept, the present invention also provides a kind of frequency based on zero initial phase benchmark cosine function times frequency sequence Embodiments of systems of the invention are described in detail by rate measuring system below in conjunction with the accompanying drawings.
As shown in figure 5, a kind of frequency measuring system based on zero initial phase benchmark cosine function times frequency sequence, including:
Preliminary sequence length determination modul 101, for the lower limit according to frequency power signal scope, preset sample frequency and Default integer signal period number, obtains preliminary sequence length;
Preliminary sequence acquisition module 102, for being sampled according to the preliminary sequence length to electric power signal, obtain institute State the preliminary sequence of electric power signal;
Reference frequency determining module 103, for entering line frequency preliminary survey to the preliminary sequence, obtain the electric power signal Preliminary frequency, reference frequency is obtained according to the preliminary frequency;
Unit period sequence length determining module 104, for according to the preset sample frequency and the reference frequency, obtaining Obtain the unit period sequence length of the electric power signal;
Preprocessing sequence length determination modul 105, for by the default integer signal period number and the unit period Sequence length is multiplied, and obtains preprocessing sequence length;
Preprocessing sequence acquisition module 106, for according to the preprocessing sequence length, from the preliminary of the electric power signal Preprocessing sequence is obtained in sequence;
Comb filtering sequence determining module 107, for carrying out comb filtering processing to the preprocessing sequence, obtain pectination Filtered sequence, wherein comb filtering sequence length are residue length of the preprocessing sequence after comb filtering processing is carried out;
Predetermined sequence length determination modul 108, for determining the comb filtering sequence length and the unit period sequence The ratio integer of row length, predetermined sequence length is obtained according to the ratio integer and the unit period sequence length, wherein The ratio integer is odd number, and the predetermined sequence length is odd number;
First ray acquisition module 109, for according to the predetermined sequence length and default starting point, being filtered from the pectination The first positive sequence is obtained in wave train, the first anti-pleat sequence is obtained according to the described first positive sequence;
First positive and negative phase determination module 110, for obtaining the first positive phase according to the described first positive sequence, according to institute State the first anti-pleat sequence and obtain the first antiphase;
First average initial phase determining module 111, for according to first positive phase and first antiphase acquisition First average initial phase;
New starting point determining module 112, for according to the described first average initial phase and preset phase value, obtaining phase ratio Compared with value, according to the phase fiducial value, the default starting point and the unit period sequence length, new starting point is obtained;
Second retrieval module 113, for according to the predetermined sequence length and the new starting point, from the pectination The second positive sequence is obtained in filtered sequence, the second anti-pleat sequence is obtained according to the second positive sequence;
Second positive and negative phase determination module 114, for obtaining the second positive phase according to the described second positive sequence, according to institute State the second anti-pleat sequence and obtain the second antiphase;
Second average initial phase determining module 115, for according to second positive phase and second antiphase acquisition Second average initial phase;
Cosine function modulation sequence determining module 116, for by the described second positive sequence and the described second anti-pleat sequence It is added, obtains and sequence, according to described and sequence and the cosine function value of the second average initial phase, obtains cosine function and adjust Sequence processed;
SIN function modulation sequence determining module 117, for by the described second positive sequence and the described second anti-pleat sequence Subtract each other, obtain difference sequence, according to the difference sequence and the sine function of the second average initial phase, obtain SIN function and adjust Sequence processed;
Zero initial phase modulation sequence acquisition module 118, for being exported from the cosine function modulation sequence central point, obtain Zero initial phase benchmark cosine function modulation sequence, exported from the SIN function modulation sequence central point, obtain zero initial phase base Quasi sinusoids modulation sequence;
Zero initial phase benchmark cosine function times frequency sequence determines sequence 119, for by the zero initial phase benchmark cosine letter Number modulation sequences square square subtract each other with the zero initial phase reference sinusoidal FUNCTION MODULATION sequence, acquisition zero initial phase benchmark Cosine function times frequency sequence;
Sequence determining module 120 is mixed, for the zero initial phase benchmark cosine function times frequency sequence to be joined with 2 times respectively The discrete cosine function multiplication for examining frequency is multiplied with the discrete sine function of 2 times of reference frequencies, obtains real frequency mixing sequence and void Frequency mixing sequence;
Filtered sequence determining module 121, for being carried out respectively to the real frequency mixing sequence and the empty frequency mixing sequence Digital filtering, obtain real frequency filtered sequence and imaginary frequency filtering sequence;
Integrated value determining module 122, for being accumulated respectively to the real frequency filtered sequence and the imaginary frequency filtering sequence Point, obtain real frequency integrated value and empty frequency integrated value;
Frequency power signal determining module 123, for according to the real frequency integrated value and empty frequency integrated value, obtaining zero first phase The phase of position benchmark cosine function times frequency sequence, the frequency of electric power signal is obtained according to the phase.
In one embodiment, the mixing sequence determining module 120 can be according to expression formula R (n)=X02cos(n)cos (2ωsTn real frequency mixing sequence R (n)) is obtained, wherein, X02cos(n) it is zero initial phase benchmark cosine function times frequency sequence, cos (2ωsTn it is) the discrete cosine function of 2 times of reference frequencies, ωsFor reference frequency, T is sampling interval duration, and n is series of discrete Number,
The mixing sequence determining module 120 can be according to expression formula I (n)=X02cos(n)sin(2ωsTn) obtain empty Frequency mixing sequence I (n), wherein, X02cos(n) it is zero initial phase benchmark cosine function times frequency sequence, sin (2 ωsTn it is) 2 times of ginsengs Examine the discrete sine function of frequency, ωsFor reference frequency, T is sampling interval duration, and n is series of discrete number,
In one embodiment, the filtered sequence determining module 121 can be calculated by rectangular window arithmetic average value filtering Method carries out digital filtering to the real frequency mixing sequence and the empty frequency mixing sequence respectively.
In one embodiment, the frequency power signal determining module 123 can be according to expression formulaThe phase PH of zero initial phase benchmark cosine function times frequency sequence is obtained, wherein, RDFor real frequency integrated value, IDFor empty frequency integrated value.
In one embodiment, the frequency power signal determining module 123 can be according to expression formulaObtain the frequencies omega of electric power signali, wherein, PH is zero initial phase benchmark cosine function frequency multiplication The phase of sequence, T are sampling interval duration, and M is integration lengths, NDJoin for the filtering of rectangular window arithmetic mean of instantaneous value filtering algorithm Number, ωsFor reference frequency.
The other technical characteristics of present system are identical with the inventive method, will not be described here.
Each technical characteristic of embodiment described above can be combined arbitrarily, to make description succinct, not to above-mentioned reality Apply all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited In contradiction, the scope that this specification is recorded all is considered to be.
Embodiment described above only expresses the several embodiments of the present invention, and its description is more specific and detailed, but simultaneously Can not therefore it be construed as limiting the scope of the patent.It should be pointed out that come for one of ordinary skill in the art Say, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to the protection of the present invention Scope.Therefore, the protection domain of patent of the present invention should be determined by the appended claims.

Claims (10)

1. a kind of frequency measurement method based on zero initial phase benchmark cosine function times frequency sequence, it is characterised in that including step:
According to the lower limit of frequency power signal scope, preset sample frequency and default integer signal period number, preliminary sequence is obtained Length;
Electric power signal is sampled according to the preliminary sequence length, obtains the preliminary sequence of the electric power signal;
Line frequency preliminary survey is entered to the preliminary sequence, obtains the preliminary frequency of the electric power signal, is obtained according to the preliminary frequency To reference frequency;
According to the preset sample frequency and the reference frequency, the unit period sequence length of the electric power signal is obtained;
The default integer signal period number is multiplied with the unit period sequence length, obtains preprocessing sequence length;
According to the preprocessing sequence length, preprocessing sequence is obtained from the preliminary sequence of the electric power signal;
Comb filtering processing is carried out to the preprocessing sequence, obtains comb filtering sequence, wherein comb filtering sequence length is Residue length of the preprocessing sequence after comb filtering processing is carried out;
The ratio integer of the comb filtering sequence length and the unit period sequence length is determined, according to the ratio integer Predetermined sequence length is obtained with the unit period sequence length, wherein the ratio integer is odd number, the predetermined sequence length Spend for odd number;
According to the predetermined sequence length and default starting point, the first positive sequence, root are obtained from the comb filtering sequence The first anti-pleat sequence is obtained according to the described first positive sequence;
First positive phase is obtained according to the described first positive sequence, the first antiphase is obtained according to the described first anti-pleat sequence;
First average initial phase is obtained according to first positive phase and first antiphase;
According to the described first average initial phase and preset phase value, phase fiducial value is obtained, according to the phase fiducial value, described Default starting point and the unit period sequence length, obtain new starting point;
According to the predetermined sequence length and the new starting point, the second positive sequence is obtained from the comb filtering sequence, Second anti-pleat sequence is obtained according to the second positive sequence;
Second positive phase is obtained according to the described second positive sequence, the second antiphase is obtained according to the described second anti-pleat sequence;
Second average initial phase is obtained according to second positive phase and second antiphase;
Described second positive sequence is added with the described second anti-pleat sequence, obtained and sequence, according to described and sequence and described The cosine function value of second average initial phase, according to expression formulaObtain cosine function Modulation sequence, wherein, Xcos(n) it is cosine function modulation sequence, X+end(n)+X-end(- n) is and sequence, cos (PHend-avg) be The cosine function value of second average initial phase;
Described second positive sequence and the described second anti-pleat sequence are subtracted each other, obtain difference sequence, according to the difference sequence and described The sine function of second average initial phase, according to expression formulaObtain SIN function Modulation sequence, wherein, Xsin(n) it is SIN function modulation sequence, X+end(n)-X-end(- n) is difference sequence, sin (PHend-avg) be The sine function of second average initial phase;
Exported from the cosine function modulation sequence central point, zero initial phase benchmark cosine function modulation sequence is obtained, from described SIN function modulation sequence central point exports, and obtains zero initial phase reference sinusoidal FUNCTION MODULATION sequence;
By the zero initial phase benchmark cosine function modulation sequence square with the zero initial phase reference sinusoidal FUNCTION MODULATION sequence Row square subtract each other, and obtain zero initial phase benchmark cosine function times frequency sequence;
The zero initial phase benchmark cosine function times frequency sequence is multiplied and 2 with the discrete cosine function of 2 times of reference frequencies respectively The discrete sine function of times reference frequency is multiplied, and obtains real frequency mixing sequence and empty frequency is mixed sequence;
Digital filtering is carried out to the real frequency mixing sequence and the empty frequency mixing sequence respectively, obtains real frequency filtered sequence and void Frequency filtered sequence;
The real frequency filtered sequence and the imaginary frequency filtering sequence are integrated respectively, real frequency integrated value is obtained and empty frequency integrates Value;
According to the real frequency integrated value and empty frequency integrated value, the phase of zero initial phase benchmark cosine function times frequency sequence of acquisition, root The frequency of electric power signal is obtained according to the phase.
2. the frequency measurement method according to claim 1 based on zero initial phase benchmark cosine function times frequency sequence, it is special Sign is, according to expression formulaThe phase PH of zero initial phase benchmark cosine function times frequency sequence is obtained, its In, RDFor real frequency integrated value, IDFor empty frequency integrated value.
3. the frequency measurement method according to claim 1 based on zero initial phase benchmark cosine function times frequency sequence, it is special Sign is, the real frequency mixing sequence and the empty frequency mixing sequence are entered respectively by rectangular window arithmetic mean of instantaneous value filtering algorithm Row digital filtering.
4. the frequency measurement method according to claim 3 based on zero initial phase benchmark cosine function times frequency sequence, it is special Sign is, according to expression formulaObtain the frequencies omega of electric power signali, wherein, PH is zero first phase The phase of position benchmark cosine function times frequency sequence, T is sampling interval duration, and M is integration lengths, NDFor rectangular window arithmetic mean of instantaneous value The filtering parameter of filtering algorithm, ωsFor reference frequency.
5. the frequency based on zero initial phase benchmark cosine function times frequency sequence according to Claims 1-4 any one is surveyed Amount method, it is characterised in that:
According to expression formula R (n)=X02cos(n)cos(2ωsTn real frequency mixing sequence R (n)) is obtained, wherein, X02cos(n) it is zero Initial phase benchmark cosine function times frequency sequence, cos (2 ωsTn it is) the discrete cosine function of 2 times of reference frequencies, ωsFor with reference to frequency Rate, T are sampling interval duration, and n is series of discrete number, n=0,1,2 ... ..,
According to expression formula I (n)=X02cos(n)sin(2ωsTn empty frequency mixing sequence I (n)) is obtained, wherein, X02cos(n) it is zero Initial phase benchmark cosine function times frequency sequence, sin (2 ωsTn it is) discrete sine function of 2 times of reference frequencies, ωsFor with reference to frequency Rate, T are sampling interval duration, and n is series of discrete number, n=0,1,2 ... ..,
A kind of 6. frequency measuring system based on zero initial phase benchmark cosine function times frequency sequence, it is characterised in that including:
Preliminary sequence length determination modul, for the lower limit according to frequency power signal scope, preset sample frequency and preset whole Number signal period number, obtains preliminary sequence length;
Preliminary sequence acquisition module, for being sampled according to the preliminary sequence length to electric power signal, obtain the electric power The preliminary sequence of signal;
Reference frequency determining module, for entering line frequency preliminary survey to the preliminary sequence, obtain the first cadence of the electric power signal Rate, reference frequency is obtained according to the preliminary frequency;
Unit period sequence length determining module, for according to the preset sample frequency and the reference frequency, described in acquisition The unit period sequence length of electric power signal;
Preprocessing sequence length determination modul, for by the default integer signal period number and the unit period sequence length It is multiplied, obtains preprocessing sequence length;
Preprocessing sequence acquisition module, for according to the preprocessing sequence length, from the preliminary sequence of the electric power signal Obtain preprocessing sequence;
Comb filtering sequence determining module, for carrying out comb filtering processing to the preprocessing sequence, obtain comb filtering sequence Row, wherein comb filtering sequence length is residue length of the preprocessing sequence after comb filtering processing is carried out;
Predetermined sequence length determination modul, for determining the comb filtering sequence length and the unit period sequence length Ratio integer, predetermined sequence length is obtained according to the ratio integer and the unit period sequence length, wherein the ratio Integer is odd number, and the predetermined sequence length is odd number;
First ray acquisition module, for according to the predetermined sequence length and default starting point, from the comb filtering sequence The first positive sequence of middle acquisition, the first anti-pleat sequence is obtained according to the described first positive sequence;
First positive and negative phase determination module, for obtaining the first positive phase according to the described first positive sequence, according to described first Anti- pleat sequence obtains the first antiphase;
First average initial phase determining module, it is average for obtaining first according to first positive phase and first antiphase Initial phase;
New starting point determining module, for according to the described first average initial phase and preset phase value, obtaining phase fiducial value, root According to the phase fiducial value, the default starting point and the unit period sequence length, new starting point is obtained;
Second retrieval module, for according to the predetermined sequence length and the new starting point, from the comb filtering sequence The second positive sequence is obtained in row, the second anti-pleat sequence is obtained according to the second positive sequence;
Second positive and negative phase determination module, for obtaining the second positive phase according to the described second positive sequence, according to described second Anti- pleat sequence obtains the second antiphase;
Second average initial phase determining module, it is average for obtaining second according to second positive phase and second antiphase Initial phase;
Cosine function modulation sequence determining module, for the described second positive sequence to be added with the described second anti-pleat sequence, obtain Arrive and sequence, according to described and sequence and the cosine function value of the second average initial phase, according to expression formulaCosine function modulation sequence is obtained, wherein, Xcos(n) sequence is modulated for cosine function Row, X+end(n)+X-end(- n) is and sequence, cos (PHend-avg) for the cosine function value of the second average initial phase;
SIN function modulation sequence determining module, for the described second positive sequence and the described second anti-pleat sequence to be subtracted each other, obtain To difference sequence, according to the difference sequence and the sine function of the second average initial phase, according to expression formulaSIN function modulation sequence is obtained, wherein, Xsin(n) sequence is modulated for SIN function Row, X+end(n)-X-end(- n) is difference sequence, sin (PHend-avg) for the sine function of the second average initial phase;
Zero initial phase modulation sequence acquisition module, for being exported from the cosine function modulation sequence central point, obtain zero first phase Position benchmark cosine function modulation sequence, is exported from the SIN function modulation sequence central point, obtains zero initial phase reference sinusoidal FUNCTION MODULATION sequence;
Zero initial phase benchmark cosine function times frequency sequence determines sequence, for the zero initial phase benchmark cosine function to be modulated into sequence Row square square subtract each other with the zero initial phase reference sinusoidal FUNCTION MODULATION sequence, acquisition zero initial phase benchmark cosine function Times frequency sequence;
Be mixed sequence determining module, for by the zero initial phase benchmark cosine function times frequency sequence respectively with 2 times of reference frequencies Discrete cosine function be multiplied and be multiplied with the discrete sine function of 2 times of reference frequencies, obtain real frequency mixing sequence and empty mixing frequently Sequence;
Filtered sequence determining module, for carrying out digital filter to the real frequency mixing sequence and the empty frequency mixing sequence respectively Ripple, obtain real frequency filtered sequence and imaginary frequency filtering sequence;
Integrated value determining module, for being integrated respectively to the real frequency filtered sequence and the imaginary frequency filtering sequence, obtain Real frequency integrated value and empty frequency integrated value;
Frequency power signal determining module, for according to the real frequency integrated value and empty frequency integrated value, obtaining zero initial phase benchmark The phase of cosine function times frequency sequence, the frequency of electric power signal is obtained according to the phase.
7. the frequency measuring system according to claim 6 based on zero initial phase benchmark cosine function times frequency sequence, it is special Sign is that the frequency power signal determining module is according to expression formulaObtain zero initial phase benchmark cosine The phase PH of function times frequency sequence, wherein, RDFor real frequency integrated value, IDFor empty frequency integrated value.
8. the frequency measuring system according to claim 6 based on zero initial phase benchmark cosine function times frequency sequence, it is special Sign is that the filtered sequence determining module is by rectangular window arithmetic mean of instantaneous value filtering algorithm respectively to the real frequency mixing sequence Digital filtering is carried out with the empty frequency mixing sequence.
9. the frequency measuring system according to claim 8 based on zero initial phase benchmark cosine function times frequency sequence, it is special Sign is that the frequency power signal determining module is according to expression formulaObtain electric power signal Frequencies omegai, wherein, PH is the phase of zero initial phase benchmark cosine function times frequency sequence, and T is sampling interval duration, and M grows for integration Degree, NDFor the filtering parameter of rectangular window arithmetic mean of instantaneous value filtering algorithm, ωsFor reference frequency.
10. the frequency based on zero initial phase benchmark cosine function times frequency sequence according to claim 6 to 9 any one is surveyed Amount system, it is characterised in that:
The mixing sequence determining module is according to expression formula R (n)=X02cos(n)cos(2ωsTn real frequency mixing sequence R) is obtained (n), wherein, X02cos(n) it is zero initial phase benchmark cosine function times frequency sequence, cos (2 ωsTn) for 2 times of reference frequencies from Dissipate cosine function, ωsFor reference frequency, T is sampling interval duration, and n is series of discrete number, n=0,1,2 ... ..,
The mixing sequence determining module is according to expression formula I (n)=X02cos(n)sin(2ωsTn empty frequency mixing sequence I) is obtained (n), wherein, X02cos(n) it is zero initial phase benchmark cosine function times frequency sequence, sin (2 ωsTn) for 2 times of reference frequencies from Dissipate SIN function, ωsFor reference frequency, T is sampling interval duration, and n is series of discrete number, n=0,1,2 ... ..,
CN201510890785.9A 2015-12-04 2015-12-04 Based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system Active CN105425040B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201510890785.9A CN105425040B (en) 2015-12-04 2015-12-04 Based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201510890785.9A CN105425040B (en) 2015-12-04 2015-12-04 Based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system

Publications (2)

Publication Number Publication Date
CN105425040A CN105425040A (en) 2016-03-23
CN105425040B true CN105425040B (en) 2018-03-23

Family

ID=55503372

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201510890785.9A Active CN105425040B (en) 2015-12-04 2015-12-04 Based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system

Country Status (1)

Country Link
CN (1) CN105425040B (en)

Citations (9)

* Cited by examiner, † Cited by third party
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

Patent Citations (9)

* Cited by examiner, † Cited by third party
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

Also Published As

Publication number Publication date
CN105425040A (en) 2016-03-23

Similar Documents

Publication Publication Date Title
CN104635044B (en) Power signal frequency detection method and system based on amplitude modulation
CN104635045B (en) Frequency power signal detection method and system based on phase-modulation
CN105067880B (en) The method and system of orthogonal modulation is carried out to electric power signal
CN104502700B (en) Sinusoidal parameter measurement method and system of power signal
CN105425031B (en) The orthogonal frequency multiplication sequence method of zero initial phase benchmark and system are obtained from electric power signal
CN105425040B (en) Based on zero initial phase benchmark cosine function frequency multiplication sequence frequency measuring method and system
CN105548688B (en) Frequency measurement method and system are carried out according to zero initial phase benchmark cosine function sequence
CN105372490B (en) The method and system of frequency measurement based on zero orthogonal times of frequency sequence of initial phase benchmark
CN105548690B (en) Based on zero initial phase reference sinusoidal function frequency multiplication sequence frequency measuring method and system
CN105548692B (en) The method and system of frequency measurement is carried out according to zero initial phase benchmark orthogonal sequence
CN105548694B (en) Frequency measurement method and system are carried out according to the zero initial phase reference sinusoidal sequence of function
CN105301356B (en) Obtain the method and system of zero initial phase benchmark cosine function times frequency sequence
CN105548693B (en) Obtain the method and system of zero initial phase reference sinusoidal function times frequency sequence
CN105425032B (en) The method and system of SIN function times frequency sequence is obtained from electric power signal
CN105403768B (en) The method and system of cosine function times frequency sequence is obtained from electric power signal
CN105388359B (en) The method and system of orthogonal times of frequency sequence is obtained from electric power signal
CN105548699B (en) Obtain the method and system of the raising frequency reference SIN function sequence of electric power signal
CN105203843B (en) The average first phase position detecting method and system of electric power signal
CN105548698B (en) Frequency power signal method for trimming and system
CN105548691B (en) Obtain the method and system of the raising frequency sine sequence of function of electric power signal
CN105548704B (en) The method and system of fine setting frequency reference sequence is obtained from electric power signal
CN105158559B (en) Electric power signal is converted to the method and system of zero initial phase sinusoidal signal sequence
CN105425035B (en) Obtain the method and system for dropping low-frequency zero initial phase reference sinusoidal sequence of function
CN105158560B (en) The method and system of orthogonal reference signals sequence is extracted from electric power signal
CN105137172B (en) Electric power signal is converted to the method and system of zero initial phase cosine signal sequence

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant