CN109066678A - A kind of improved APF system harmonics electric current detecting method - Google Patents
A kind of improved APF system harmonics electric current detecting method Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/01—Arrangements for reducing harmonics or ripples
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0092—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring current only
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- G—PHYSICS
- G01—MEASURING; TESTING
- 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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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
- H02J2203/20—Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/20—Active power filtering [APF]
Abstract
The invention discloses a kind of improved APF system harmonics electric current detecting methods, using improved FBD algorithm, by threephase load electric current ia(t)、ib(t)、ic(t) it is calculated with the reference voltage ginseng obtained by PLL, obtains active equivalent conductance and idle equivalent conductance；Using improved ip‑iqMethod obtains active current i after active equivalent conductance and idle equivalent conductance are carried out linear transformation firstp(t) and reactive current component iq(t)；Then active current i is extracted using improved moving average methodp(t) and reactive current component iq(t) DC component inWithFinally calculate three phase harmonic current reference valuePresent invention reduces the complexity that harmonic current calculates, and improve the precision and response speed of detection, improved harmonic detecting method is compared to traditional algorithm, so that the static state and dynamic property of system are all significantly improved.
Description
Technical field
The invention belongs to power electronics fields, and in particular to a kind of improved APF system harmonics electric current detecting method.
Background technique
APF system function realize premise be Harmonic currents detection link can real-time and accurately detect to load it is contained
Harmonic current, therefore the accuracy of harmonic current detection and rapidity will directly affect the compensation effect of APF system.Mesh
Before, the common Harmonic Detecting Algorithm of APF system mainly has: 1. based on the detection method of instantaneous reactive power theory.This method mesh
Before be to be most widely used in APF system, developed p-q method, ip-iqMethod and d-q method.Wherein, p-q method is application
Earliest harmonic detecting method, and it is only applicable to three-phase symmetrical and distortionless APF system；ip-iqRule has wide range of applications,
For asymmetry and there is the system of distortion equally applicable, and detection error is small compared with p-q method；D-q method is converted based on Park, no
Only simplify the detection for three-phase symmetrical and distortionless APF system, the system for being also applied for asymmetrical three-phase, having distortion.
2. band logical, bandstop filter and harmonic device detection method based on frequency-domain analysis simulated implementation.The detection method circuit structure is simple,
It is at low cost, quality factor are easily controllable, but and error very sensitive to component parameters is larger, therefore is rarely employed.3. based on frequency
The Discrete Fourier Transform detection method of domain analysis.This method needs to carry out Fourier transformation and its inverse transformation, therefore calculation amount is very big,
There are hysteresis qualitys, especially when waveform distortion of the power supply network is serious or frequency fluctuation, significantly impact the detection essence of harmonic current
Degree.4. FBD detection method.This method is a kind of tim e- domain detection method, not complicated Park transformation and Clark transformation, and algorithm is simple,
But this method can not capacitance voltage up and down directly to APF system carry out Pressure and Control.5. adaptive detective method.This method is directed to
Many situations such as single-phase or three-phase circuit voltage distortion, electrical network parameter variation and frequency shift (FS) can be adjusted adaptively
It is whole, but dynamic response effect is poor.
The above common current harmonics detection algorithm all respectively has advantage and disadvantage to derive it how by further analyzing
In two or more algorithms between inner link and blended, form a kind of new detection algorithm, be then the present invention
The purpose of research.Based on this, the present invention derives by analysis, finds common FBD detection method and is managed based on instantaneous reactive power
The i of opinionp-iqInner link between method, and finally combine two kinds of algorithms, propose a kind of new current harmonics detection algorithm.
Summary of the invention
The object of the present invention is to provide a kind of improved APF system harmonics electric current detecting methods, and the method overcome tradition
FBD detection method and ip-iqThe deficiency of method eliminates unnecessary zero-sequence current separation link, and reduces coordinate transform bring
Matrix operation improves the reliability and real-time of algorithm；Traditional LPF is replaced using improved rolling average algorithm, is solved
While upper and lower capacitor voltage balance problem, the real-time and precision of harmonic detecting are improved.
The technical scheme adopted by the invention is that a kind of improved APF system harmonics electric current detecting method, specific implementation step
It is rapid as follows:
Step 1: improved FBD algorithm is used, by threephase load electric current ia(t)、ib(t)、ic(t) ginseng and obtained by PLL
It examines voltage ginseng to be calculated, obtains active equivalent conductance and idle equivalent conductance；
Step 2: using improved ip-iqMethod, the active equivalent conductance and idle equivalent conductance for first obtaining step 1 into
Active current i is obtained after row linear transformationp(t) and reactive current component iq(t)；Then improved moving average is used
Method extracts active current ip(t) and reactive current component iq(t) DC component inWith
Step 3: calculating three phase harmonic current reference value
The features of the present invention also characterized in that
Step 1 obtains active equivalent conductance and idle equivalent conductance, and the specific method is as follows:
System voltage reference vector is u=(u1,u2,...,um), current phasor i=(i1,i2,...,im), the member of vector
Element is respectively each phase voltage, current instantaneous value, and related definition is as follows:
Instantaneous power:
Instantaneous voltage:
It can be obtained by formula (1-1) and (1-2), active equivalent conductance and idle equivalent conductance are defined as follows:
Wherein, upFor active voltage, uqFor reactive voltage, Pq∑It (t) is t moment instantaneous reactive power, Pp∑It (t) is t moment
Instantaneous active power；The element u of vector1,u2,...,umAnd i1,i2,...,imRespectively each phase voltage, current instantaneous value.
Circuit three-phase voltage and electric current are substituted into formula (1-3), its active equivalent conductance can be obtained:
Symmetrical three-phase alternating current summation, obtains sin ω t+sin (ω t-120 °)+sin (ω t+120 °)=0, therefore can
:
Its idle equivalent conductance can similarly be obtained:
Active equivalent conductance G can be obtained by formula (1-6) and (1-7)p(t) and idle equivalent conductance Gq(t) are as follows:
N represents 1 to infinitely great positive integer, I1nFor forward-order current in three-phase four-wire system, I0nFor three-phase four-wire system
Zero-sequence current in system, I2nFor negative-sequence current in three-phase four-wire system, t is time, φ1nFor the initial phase of forward-order current,
φ2nFor the initial phase of negative-sequence current, φ0nFor the initial phase of zero-sequence current.
Active current i is calculated described in step 2p(t) and reactive current component iq(t) DC component inWith's
Method are as follows:
Active current is obtained after active equivalent conductance that step 1 obtains and idle equivalent conductance are carried out linear transformation
ip(t) and reactive current component iq(t):
Instantaneous active electric current ip(t) and instantaneous reactive current iq(t) it is respectively:
Active current i is extracted using improved moving average methodp(t) and reactive current component iq(t) it extracts respectively
Active current ip(t) DC componentWith reactive current component iq(t) DC component
In formula: ipIt (k) is the real time data of k-th of sampled point of watt current, ipIt (k-N) is a cycle in watt current
The data most lagged in interior N number of sampled point, ip(l) data are summed for watt current sampling.
In formula: iqIt (k) is the real time data of k-th of sampled point of reactive current, iqIt (k-N) is a cycle in reactive current
The data most lagged in interior N number of sampled point, iq(l) data are summed for reactive current sampling.
Step 3 calculates three phase harmonic current reference valueMethod particularly includes:
The zero-axis current increment Delta i that upper and lower capacitor grading ring pi regulator is generated0It is added to and carries out individually extracting zero axle
In electric current, zero-sequence current reference value is generatedThe current increment Δ i that DC voltage and upper and lower capacitor grading ring are generatedpIt is folded
It is added in watt current, generates watt current reference valueReactive current reference valueThen directly by reactive current component iq
(t) and reactive current DC componentSuperimposed acquisition；Active and reactive current reference valueWith zero-sequence current
Reference valueIt is converted together by anti-Park and anti-Clark, obtains three phase harmonic current reference value
The invention has the advantages that the APF system harmonics electric current detecting method of a modification of the present invention is using improvement
FBD algorithm, eliminate zero-sequence current and kick the link removed, directly three-phase current substitution is calculated, obtains active equivalent electricity
Lead with idle equivalent conductance, reduce the complexity of calculating；Improved i is used againp-iqMethod, by the active equivalent conductance of acquisition and
Idle equivalent conductance obtains active current i after carrying out linear transformationp(t) and reactive current component iq(t), on this basis
In order to improve the precision and response speed of detection, DC component is extracted using improved moving average method, and to zero-axis current
It individually extracts, Pressure and Control is carried out to upper and lower capacitance voltage.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the APF system harmonics electric current detecting method of a modification of the present invention；
Fig. 2 is the current simulations waveform in conventional current detection method；
Fig. 3 is the current simulations waveform in the APF system harmonics electric current detecting method of a modification of the present invention；
Fig. 4 is traditional instantaneous detecting method source current frequency analysis figure；
Fig. 5 is the improvement Harmonic detection power supply electricity of the APF system harmonics electric current detecting method of a modification of the present invention
Flow frequency analysis figure.
Specific embodiment
The following describes the present invention in detail with reference to the accompanying drawings and specific embodiments.
The process of the APF system harmonics electric current detecting method of a modification of the present invention is as shown in Figure 1, concrete operation step
It is as follows:
Step 1: improved FBD algorithm is used, by threephase load electric current ia(t)、ib(t)、ic(t) ginseng and obtained by PLL
It examines voltage ginseng to be calculated, obtains active equivalent conductance and idle equivalent conductance；
Step 1 obtains active equivalent conductance and idle equivalent conductance, and the specific method is as follows:
System voltage reference vector is u=(u1,u2,...,um), current phasor i=(i1,i2,...,im), the member of vector
Element is respectively each phase voltage, current instantaneous value, and related definition is as follows:
Instantaneous power:
Instantaneous voltage:
It can be obtained by formula (1-1) and (1-2), active equivalent conductance and idle equivalent conductance are defined as follows:
Wherein, upFor active voltage, uqFor reactive voltage, Pq∑It (t) is t moment instantaneous reactive power, Pp∑It (t) is t moment
Instantaneous active power；The element u of vector1,u2,...,umAnd i1,i2,...,imRespectively each phase voltage, current instantaneous value.
Traditional FBD algorithm applies in three-phase four-wire system APF, usually first calculates the zero-sequence component of three-phase current, then should
Zero-sequence current is rejected, and is finally again substituted into formula 1-3 three-phase voltage with the three-phase current for eliminating zero-sequence component, be can be calculated:
ia(t)、ib(t)、ic(t) a, b, c threephase load electric current are respectively represented, n represents 1 to infinitely great positive integer, I1n
For forward-order current in three-phase four-wire system, I0nFor zero-sequence current in three-phase four-wire system, I2nFor in three-phase four-wire system
Negative-sequence current, t are time, φ1nFor the initial phase of forward-order current, φ2nFor the initial phase of negative-sequence current, φ0nFor zero-sequence current
Initial phase.
It in order to avoid the calculating of traditional FBD algorithm complicates, keeps the succinct of algorithm and stablizes, now attempt zero sequence electricity not
Circuit three-phase voltage and electric current are directly substituted into formula (1-3), can obtain its active equivalent conductance by flow separation:
Symmetrical three-phase alternating current summation, obtains sin ω t+sin (ω t-120 °)+sin (ω t+120 °)=0, therefore can
:
Its idle equivalent conductance can similarly be obtained:
Active equivalent conductance G can be obtained by formula (1-6) and (1-7)p(t) and idle equivalent conductance Gq(t) are as follows:
N represents 1 to infinitely great positive integer, I1nFor forward-order current in three-phase four-wire system, I0nFor three-phase four-wire system
Zero-sequence current in system, I2nFor negative-sequence current in three-phase four-wire system, t is time, φ1nFor the initial phase of forward-order current,
φ2nFor the initial phase of negative-sequence current, φ0nFor the initial phase of zero-sequence current.
Comparison expression 1-4 and 1-8 can be obtained, and direct substitute into circuit three-phase voltage and electric current that the present invention uses calculates,
Obtained equivalent conductance size first separates the zero-sequence current in three-phase current with tradition FBD algorithm, then carries out operation acquisition
Equivalent conductance size is identical, to demonstrate the feasibility using improved FBD algorithm；
Step 2: using improved ip-iqMethod, the active equivalent conductance and idle equivalent conductance for first obtaining step 1 into
Active current i is obtained after row linear transformationp(t) and reactive current component iq(t)；Then improved moving average is used
Method extracts active current ip(t) and reactive current component iq(t) DC component inWith
Active current is obtained after active equivalent conductance that step 1 obtains and idle equivalent conductance are carried out linear transformation
ip(t) and reactive current component iq(t):
If three-phase reference voltage are as follows:
Three-phase current is represented by the sum of forward-order current, negative-sequence current and zero-sequence current, and subscript 1,2,0 respectively indicates three
Positive sequence, negative phase-sequence, zero-sequence current in phase four-wire system system.
Traditional ip-iqDetection method is used in three-phase four-wire system APF, is generated and a phase voltage using phaselocked loop (PLL)
With the sinusoidal and cosine signal of phase, threephase load electric current is converted by Clark transformation and Park, is obtained instantaneous under new coordinate system
Watt current ip(t), instantaneous reactive current iq(t), current in middle wire i0(t), calculating process are as follows:
Wherein:
Formula (2-3) and (1-4) are compared and can be obtained, instantaneous active electric current ip(t) and instantaneous reactive current iqIt (t) is FBD respectively
Active equivalent conductance G in algorithmp(t) and idle equivalent conductance Gq(t)WithTimes, it may be assumed that
Finally according to the inner link between formula 1-8 and 2-5, two kinds of harmonic detecting methods can be combined, algorithm
First half use improved FBD method, by threephase load electric current ia(t)、ib(t)、ic(t) and by PLL (Phase Locked
Loop is phaselocked loop) obtained reference voltage by operation, obtains equivalent active conductance Gp(t) and equivalent idle conductance Gq(t),
Then function current component i is calculated according to formula (2-5)p(t) and reactive current component iq(t)。
Active current i is extracted using improved moving average methodp(t) and reactive current component iq(t) it extracts respectively
Active current ip(t) DC componentWith reactive current component iq(t) DC component
Before carrying out DC component extraction, under d-q coordinate system, not only respectively corresponded in the DC quantity of d axis and q axis negative
The fundamental active power and First Harmonic Reactive Power of load, and have the property that the straight of all samplings in a 1. power frequency period
Flow component is added, then divided by sampling number, as a result remains as the direct current signal；2. and in a power frequency period all samplings friendship
Flow component is added, then is as a result but zero divided by sampling number.
Accordingly, enabling a power frequency period sampling number is N, to being averaged after the value summation of all sampled points, can be obtained
To DC component.If but only do so, there are hysteresis qualitys, cannot accurately track the real-time change of signal.For this purpose, using improving
Moving average method, when sample k-th when, with the real time value i of the sampled pointd(k) it is adopted instead of N number of in upper a cycle
The data i most lagged in sampling pointd(k-N), that is, have:
In formula: idIt (k) is the real time data of k-th of sampled point, idIt (k-N) is most stagnant in N number of sampled point in upper a cycle
Data afterwards, id(l) data are summed for sampling.
According to above-mentioned principle, watt current DC component can be obtainedWith the DC component of reactive currentIt is respectively as follows:
In formula: ipIt (k) is the real time data of k-th of sampled point of watt current, ipIt (k-N) is a cycle in watt current
The data most lagged in interior N number of sampled point, ip(l) data are summed for watt current sampling.
In formula: iqIt (k) is the real time data of k-th of sampled point of reactive current, iqIt (k-N) is a cycle in reactive current
The data most lagged in interior N number of sampled point, iq(l) data are summed for reactive current sampling.
Data of such every sampling, so that it may the size for recalculating a DC component, according to formula (2-7) and (2-
8) it is found that moving average can also change therewith.Thus, it is only necessary to which the new data of a sampled point can calculate newly
Input signal DC component, the sampling period that is delayed theoretically only is needed, to keep DC component according to the actual situation
Real-time change embodies the rapidity and real-time of data update.
Step 3: the zero-axis current increment Delta i that upper and lower capacitor grading ring pi regulator is generated0It is added to and is individually mentioned
It takes in zero-axis current, generates zero-sequence current reference valueThe electric current that DC voltage and upper and lower capacitor grading ring generate is increased
Measure Δ ipIt is added in watt current, generates watt current reference valueReactive current reference valueThen directly by idle electricity
Flow component iq(t) and reactive current DC componentSuperimposed acquisition；Active and reactive current reference valueWith zero sequence
The reference value of electric currentIt is converted together by anti-Park and anti-Clark, obtains three phase harmonic current reference value
In order to verify the feasibility and superiority of algorithm proposed by the invention, emulation mould is established with simulation software MATLAB
Type has carried out simulation analysis, and system emulation parameter is as shown in table 1.
1 simulation parameter of table
| Supply voltage | Usn | 220V |
| Mains frequency | f | 50Hz |
| Switching frequency | fs | 9600Hz |
| APF output filter capacitor | L | 0.45mH |
| DC bus capacitor | CdcuCdcL | 10000uF |
| Load resistance | RL | 15ohm |
| DC voltage | Udc | 700V |
1. the simulation analysis of static characteristic
Static system performance is influenced in order to verify improved Harmonic Detecting Algorithm compared to traditional instantaneous detecting method
Superiority, respectively to system load electric current, output order electric current, output compensation electric current and compensated source current waveform into
Emulation is gone, as a result as shown in Figures 2 and 3.As seen from the figure, Harmonic Detecting Algorithm proposed by the invention can accurately detect
Load harmonic current, in this, as the output order electric current of APF, source current close sine after APF exports current compensation,
Total harmonic distortion factor (Total Harmonic Distortion, THD) is dropped to compensated by 23.88% before compensating
3.81%, it is more preferable than the compensation effect 4.99% with Traditional Instantaneous Reactive detection algorithm.Thus illustrate, with improved harmonic wave
Detection algorithm enables the more accurate detection system harmonic wave of APF to have and preferably mend under the effect of identical current controller
Repay performance.
2. the simulation analysis of dynamic characteristic
In order to verify improve harmonic wave algorithm compared to traditional instantaneous detecting method system dynamic characteristic is influenced it is superior
Property, in t=0.2s, in the resistance of load one R=15 Ω of both ends parallel connection, traditional algorithm and algorithmic system of the invention load
Shown in response curve following Fig. 4 and Fig. 5 with harmonic wave instruction current.As seen from the figure, traditional instantaneous reactive power algorithm obtains
The instruction current instruction that needs to get to new stable state by 3 periods, and obtained using improved Harmonic Detecting Algorithm
Electric current only need to can reach new stable state by 2 periods.Thus illustrate, more rapid can be kept up with using improved harmonic wave algorithm
The mutation of load, more real-time accurate detection go out the variation of harmonic current, have better dynamic response performance.
In order to more rapidly effectively detect the harmonic current in APF, the present invention is by traditional instantaneous detecting method and FBD
Method combines, and proposes a kind of improved harmonic detecting method.This method eliminates unnecessary zero-sequence current separation link, reduces
The complexity of algorithm；Reduce traditional instantaneous reactive power algorithm because of coordinate transform bring matrix operation, effectively reduces
Calculation amount saves software memory space, alleviates software burden, improves the dynamic property of harmonic detecting；To zero-axis current
It is individually extracted, and Pressure and Control is carried out to upper and lower capacitor, overcoming can not be to directly in capacitor point in traditional FBD algorithm
The capacitor up and down of formula APF carries out the deficiency of Pressure and Control, compensation shortcoming flexibility, it is ensured that algorithm divides in three-phase four-wire system capacitor
Feasibility in formula APF；Traditional LPF is replaced using improved rolling average algorithm, avoids producing in LPF sampling and calculating process
Raw hysteresis error improves harmonic detecting precision.The method proposed improves active power filtering for improving harmonic detecting performance
Device compensation effect has practical significance, and can further explore the application in three-phase four-wire system four bridge legs APF on this basis
With improvement.
Claims (4)
1. a kind of improved APF system harmonics electric current detecting method, which is characterized in that specific steps are as follows:
Step 1: improved FBD algorithm is used, by threephase load electric current ia(t)、ib(t)、ic(t) and by PLL the reference electricity obtained
Pressure ginseng is calculated, and active equivalent conductance and idle equivalent conductance are obtained；
Step 2: using improved ip-iqMethod, the active equivalent conductance for first obtaining step 1 and idle equivalent conductance carry out line
Property transformation after obtain active current ip(t) and reactive current component iq(t)；Then it is mentioned using improved moving average method
Take active current ip(t) and reactive current component iq(t) DC component inWith
Step 3: calculating three phase harmonic current reference value
2. a kind of improved APF system harmonics electric current detecting method according to claim 1, which is characterized in that the step
The specific method is as follows for the rapid 1 active equivalent conductance of acquisition and idle equivalent conductance:
System voltage reference vector is u=(u1,u2,...,um), current phasor i=(i1,i2,...,im), the element point of vector
Not Wei each phase voltage, current instantaneous value, related definition is as follows:
Instantaneous power:
Instantaneous voltage:
It can be obtained by formula (1-1) and (1-2), active equivalent conductance and idle equivalent conductance are defined as follows:
Wherein, upFor active voltage, uqFor reactive voltage, Pq∑It (t) is t moment instantaneous reactive power, Pp∑(t) instantaneous for t moment
Active power；The element u of vector1,u2,...,umAnd i1,i2,...,imRespectively each phase voltage, current instantaneous value；
Circuit three-phase voltage and electric current are substituted into formula (1-3), its active equivalent conductance can be obtained:
Symmetrical three-phase alternating current summation, obtains sin ω t+sin (ω t-120 °)+sin (ω t+120 °)=0, therefore can obtain:
Its idle equivalent conductance can similarly be obtained:
Active equivalent conductance G can be obtained by formula (1-6) and (1-7)p(t) and idle equivalent conductance Gq(t) are as follows:
N represents 1 to infinitely great positive integer, I1nFor forward-order current in three-phase four-wire system, I0nFor three-phase four-wire system
Middle zero-sequence current, I2nFor negative-sequence current in three-phase four-wire system, t is time, φ1nFor the initial phase of forward-order current, φ2nFor
The initial phase of negative-sequence current, φ0nFor the initial phase of zero-sequence current.
3. a kind of improved APF system harmonics electric current detecting method according to claim 1, which is characterized in that step 2 institute
It states and calculates active current ip(t) and reactive current component iq(t) DC component inWithMethod are as follows:
The active equivalent conductance that step 1 is obtained and idle equivalent conductance obtain active current i after carrying out linear transformationp(t)
With reactive current component iq(t):
Instantaneous active electric current ip(t) and instantaneous reactive current iq(t) it is respectively:
Active current i is extracted using improved moving average methodp(t) and reactive current component iq(t) it extracts respectively active
Current component ip(t) DC componentWith reactive current component iq(t) DC component
In formula: ipIt (k) is the real time data of k-th of sampled point of watt current, ipIt (k-N) is N number of in a cycle in watt current
The data most lagged in sampled point, ip(l) data are summed for watt current sampling.
In formula: iqIt (k) is the real time data of k-th of sampled point of reactive current, iqIt (k-N) is N number of in a cycle in reactive current
The data most lagged in sampled point, iq(l) data are summed for reactive current sampling.
4. a kind of improved APF system harmonics electric current detecting method according to claim 3, which is characterized in that step 3 meter
Calculate three phase harmonic current reference valueMethod particularly includes:
The zero-axis current increment Delta i that upper and lower capacitor grading ring pi regulator is generated0It is added to and carries out individually extracting zero-axis current
In, generate zero-sequence current reference valueThe current increment Δ i that DC voltage and upper and lower capacitor grading ring are generatedpIt is added to
In watt current, watt current reference value is generatedReactive current reference valueThen directly by reactive current component iq(t)
With reactive current DC componentSuperimposed acquisition；Active and reactive current reference valueWith the reference of zero-sequence current
ValueIt is converted together by anti-Park and anti-Clark, obtains three phase harmonic current reference value
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| CN110323748A (en) * | 2019-05-28 | 2019-10-11 | 西安航空职业技术学院 | A kind of current controller optimal control method of Active Power Filter-APF |
| CN110531138A (en) * | 2019-07-08 | 2019-12-03 | 江苏科技大学 | A kind of Active Power Filter Harmonic Currents detection method |
| CN110907686A (en) * | 2019-09-16 | 2020-03-24 | 国网河南省电力公司郑州供电公司 | Distributed photovoltaic grid-connected system harmonic detection method based on FBD method |
| CN113363963A (en) * | 2021-05-20 | 2021-09-07 | 南昌大学 | Optimized three-phase SAPF direct current side control method by improving sparrow search algorithm |
| CN113804942A (en) * | 2021-07-28 | 2021-12-17 | 国网冀北电力有限公司电力科学研究院 | Resistive current monitoring method and system for voltage limiter of series compensation device |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106532705A (en) * | 2015-12-31 | 2017-03-22 | 安徽天电能质量技术有限公司 | Three-phase four-line APF calculation method of sub-harmonic compensation under multiple synchronous rotating coordinate systems |
-
2018
- 2018-08-28 CN CN201810987233.3A patent/CN109066678A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106532705A (en) * | 2015-12-31 | 2017-03-22 | 安徽天电能质量技术有限公司 | Three-phase four-line APF calculation method of sub-harmonic compensation under multiple synchronous rotating coordinate systems |
Non-Patent Citations (1)
| Title |
|---|
| 王裕: "三相四线制有源电力滤波器关键技术研究", 《中国博士学位论文全文数据库 工程科技Ⅱ辑》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110323748A (en) * | 2019-05-28 | 2019-10-11 | 西安航空职业技术学院 | A kind of current controller optimal control method of Active Power Filter-APF |
| CN110531138A (en) * | 2019-07-08 | 2019-12-03 | 江苏科技大学 | A kind of Active Power Filter Harmonic Currents detection method |
| CN110907686A (en) * | 2019-09-16 | 2020-03-24 | 国网河南省电力公司郑州供电公司 | Distributed photovoltaic grid-connected system harmonic detection method based on FBD method |
| CN113363963A (en) * | 2021-05-20 | 2021-09-07 | 南昌大学 | Optimized three-phase SAPF direct current side control method by improving sparrow search algorithm |
| CN113804942A (en) * | 2021-07-28 | 2021-12-17 | 国网冀北电力有限公司电力科学研究院 | Resistive current monitoring method and system for voltage limiter of series compensation device |
| CN113804942B (en) * | 2021-07-28 | 2024-04-12 | 国网冀北电力有限公司电力科学研究院 | Resistive current monitoring method and system for voltage limiter of series compensation device |
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