CN105140923A - Active filtering method and filter - Google Patents
Active filtering method and filter Download PDFInfo
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- CN105140923A CN105140923A CN201510586075.7A CN201510586075A CN105140923A CN 105140923 A CN105140923 A CN 105140923A CN 201510586075 A CN201510586075 A CN 201510586075A CN 105140923 A CN105140923 A CN 105140923A
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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
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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- Y02E40/40—Arrangements for reducing harmonics
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Abstract
The present invention relates to an active filtering method and a filter. The filter comprises a gradation detection module, a concentration electric current loop controller, a PWM module and an inverter. The filtering method comprises the following steps: employing the gradation detection module to collect a three-phase current of a load side; obtaining a current under a fundamental frequency rotating coordinate system through transformation of coordinates; employing a selective harmonic compensation method based on an instantaneous reactive power theory to perform compensation in sections and times; in order inputting the compensating current into the concentration electric current loop controller and the PWM module to convert the compensating current to an impulse waveform current; and converting the impulse waveform current to a harmonic current required to be compensated through driving the inverter. According to the invention, the problems of the slow system dynamic response speed of the FFT (Fast Fourier Transformation) mode, the bandwidth problem existing in the harmonic detection technology based on the instantaneous reactive power theory, and the compensation precision problem existing in the selective harmonic current detection technology are solved; and moreover, the cost of the device is reduced, and the stability of the system is improved.
Description
Technical field
The present invention relates to electronic filter technical field, particularly a kind of active power filtering method and filter.
Background technology
At present, Active Power Filter-APF is mainly divided into from the angle of Harmonic currents detection: based on FFT(FastFourierTransformation, fast fourier transform) harmonic current inspection, the Harmonic currents detection based on Instantaneous Power Theory and the APF(Activepowerfilter without Harmonic currents detection, Active Power Filter-APF).On this basis, for specific occasion, have scholar to propose the algorithm of specifying subharmonic to eliminate, gradation Instantaneous Power Theory being extended to each harmonic detects, and then superposition obtains total harmonic current.Harmonic current finally obtains vector modulation current signal by current controller, enters PWM and obtains corresponding switching tube drive singal, and delivered on power switch pipe corresponding to inverter.
Although subharmonic electric current loop independently controls the compensation precision that can improve APF, amount of calculation and the delay of controller can be increased, reduce the dynamic responding speed of system, simultaneously, when needing the harmonic number of filtering more, very high to the hardware requirement of single control chip, the cost of meeting increasing device; Or adopt multiple control chip to carry out Collaborative Control, while increasing cost, owing to relating to the synchronous of multiple CPU, the stability of system can be reduced.
Harmonic currents detection part: (1), according to the mode of FFT, can detect each harmonic, but the response time needing a cycle, reduce the dynamic responding speed of system to a great extent, and require higher to controller.(2) based on the Harmonic currents detection technology of Instantaneous Power Theory, can directly obtain whole harmonic currents, response speed is very fast, but just can only control together all harmonic waves like this, and the restriction of bandwidth can affect APF harmonic compensation precision.(3) according to the appointment subharmonic current detection technique based on Instantaneous Power Theory, all need when detecting every subharmonic current to carry out twice coordinate transform, when selected harmonic number is more, very high to the requirement of controller, or adopt multi-CPU Collaborative Control, increase cost and the stability of reduction system.By the control chip of existing market main flow, on the basis considering cost, if select the harmonic number of filtering too much, be difficult to meet the demands, thus often select the harmonic number can chosen when specifying subharmonic filtering to be generally no more than 6 in practical application.
Summary of the invention
Main purpose of the present invention is, for above-mentioned deficiency of the prior art, a kind of active power filtering method and filter are provided, its can overcome the system dynamic responding speed of FFT mode slow, based on Instantaneous Power Theory harmonic detecting technique existing for bandwidth problem and adopt the compensation precision problem of specifying existing for subharmonic current detection technique merely, equipment cost can be reduced again, the stability of elevator system.
For achieving the above object, the present invention by the following technical solutions.
The invention provides a kind of active power filtering method, comprise the following steps:
Gather the three-phase current of load-side;
Obtain the electric current under fundamental frequency rotating coordinate system by coordinate transform, adopt the appointment subharmonic penalty method based on Instantaneous Power Theory to carry out sectional, gradation compensation to harmonic wave;
By current loop controller in offset current successively input set and PWM module, to convert impulse waveform electric current to;
Utilize and drive inverter to become to need the harmonic current compensated by described impulse waveform current conversion.
In said method, the step of the three-phase current of described collection load-side specifically comprises:
Set harmonic number according to the actual requirements and carry out appointment subharmonic current and detect.
In said method, the described electric current obtained by coordinate transform under fundamental frequency rotating coordinate system, adopts the step that appointment subharmonic penalty method carries out sectional to harmonic wave, gradation compensates based on Instantaneous Power Theory specifically to comprise:
After the change anglec of rotation and transformation matrix of coordinates obtain individual harmonic current, select the required harmonic current number of times compensated, be then added the harmonic current that just can obtain needing compensation.
In said method, described by current loop controller in offset current successively input set and PWM module, specifically comprise with the step converting impulse waveform electric current to:
The number of times of the harmonic current that the interval set according to the actual requirements comprises, adopt and calculate based on the appointment subharmonic algorithm of Instantaneous Power Theory this few subharmonic current that this interval comprises, after the harmonic current in each interval is superposed separately, deliver in the concentrated current loop controller in interval corresponding with it, obtain the instruction harmonic current that modules exports, then drive inverter to export the required harmonic current compensated by the PWM module pulse signal obtaining corresponding to this module corresponding to each power switch pipe of inverter.
The present invention also correspondingly provides a kind of Active Power Filter-APF, and it comprises:
Gradation detection module, for needing to set the harmonic number of filtering and carrying out the detection of appointments subharmonic current in setting module according to the actual requirements;
Concentrating current loop controller, for receiving described harmonic current, and carrying out segmented centralized control according to the actual requirements, to eliminate the static difference that different harmonic frequency is brought;
PWM module, regulates the pulsewidth of harmonic current;
Inverter, for becoming to need the harmonic current compensated by described impulse waveform current conversion,
Described gradation detection module, concentrated current loop controller, PWM module and inverter adopt Split moduleization design.
In above-mentioned filter, set section according to the actual requirements, a gradation detection module and a concentrated current loop controller are set respectively in each interval.
In above-mentioned filter, described PWM module and inverter by the gradation detection module of all sections and concentrated current loop controller share.
In above-mentioned filter, a PWM module and an inverter are set respectively in each interval, and the gradation detection module in each interval, concentrated current loop controller, PWM module are connected successively with inverter.
The present invention, compared to traditional filtering method, has the following advantages:
(1), while guaranteed output exports, the higher compensation precision of quality of power supply product and dynamic responding speed is realized with same cost;
(2) the hardware designs difficulty of modules is reduced;
(3) the Software for Design difficulty of modules is reduced;
(4) improve the stability of quality of power supply product complete machine;
(5) be convenient to quality of power supply product promote to wider filter range.
Accompanying drawing explanation
Fig. 1 is the schematic flow sheet of active power filtering method in the embodiment of the present invention.
Fig. 2 is the theory diagram of specifying subharmonic detection method in the embodiment of the present invention.
Fig. 3 is the structured flowchart of Active Power Filter-APF in one embodiment of the invention.
Fig. 4 is the structured flowchart of Active Power Filter-APF in another embodiment of the present invention.
The realization of the object of the invention, functional characteristics and advantage will in conjunction with the embodiments, are described further with reference to accompanying drawing.
Embodiment
Describe technical scheme of the present invention in detail below with reference to drawings and the specific embodiments, so as clearer, understand invention essence of the present invention intuitively.
With reference to shown in Fig. 1, active power filtering method of the present invention can be used for, in electric power system or other quality of power supply product, being mainly used in filtering multiple harmonic and carrying out active compensation.The method mainly comprises the following steps:
S10: the three-phase current gathering load-side;
S20: obtain the electric current under fundamental frequency rotating coordinate system by coordinate transform, adopts the appointment subharmonic penalty method based on Instantaneous Power Theory to carry out sectional, gradation compensation to harmonic wave;
S30: by current loop controller in offset current successively input set and PWM module, to convert impulse waveform electric current to;
S40: utilize and drive inverter to become to need the harmonic current compensated by impulse waveform current conversion.
Step S10 specifically comprises:
Set harmonic number according to the actual requirements and carry out specifying the detection of subharmonic.
Step S20 specifically comprises:
After the change anglec of rotation and transformation matrix of coordinates obtain individual harmonic current, select the required harmonic current number of times compensated, be then added the harmonic current that just can obtain needing compensation.
Step S30 specifically comprises:
The number of times of the harmonic current that the interval set according to the actual requirements comprises, adopt and calculate based on the appointment subharmonic algorithm of Instantaneous Power Theory this few subharmonic current that this interval comprises, after the harmonic current in each interval is superposed separately, deliver in the concentrated current loop controller in interval corresponding with it, obtain the instruction harmonic current that modules exports, then drive inverter to export the required harmonic current compensated by the PWM module pulse signal obtaining corresponding to this module corresponding to each power switch pipe of inverter.
With reference to shown in Fig. 2, current transformer gathers the three-phase current of load-side, obtains the current i under frequency rotating coordinate system corresponding to appointment subharmonic by coordinate transform
pnand i
qn, as the formula (1).
（1）
By i
pn, i
qnthrough LPF(LowPassFilter, low pass filter) after obtain specifying subharmonic current i through anti-coordinate transform again
an, i
bn, i
cn, as the formula (2).
（2）
Like this, when carrying out harmonic current computing, selecting the harmonic current number of times that will compensate, then performing add operation, just can obtain the harmonic current total amount of corresponding number of times.
In order to improve the compensation precision of system, the present embodiment adopts autonomous sectional to concentrate current loop control, can determine sectional fineness according to the actual demand at scene.The controller of different control effects can be chosen according to demand, comprise various conventional controller, as PI controller or fuzzy controller etc.
Then, by current loop controller in above-mentioned offset current successively input set and PWM module, impulse waveform electric current is converted thereof into.Then drive inverter to export the required harmonic current compensated by this pulse signal, finally realize accurate harmonic compensation effect.
Compare complete time penalty method, the appointment subharmonic detection method of the present embodiment changes the anglec of rotation and transformation matrix of coordinates can obtain individual harmonic current.Such as, think elimination n-th subharmonic, because phase three-wire three circuit does not exist neutral harmonic current, only according to the positive and negative sequence of selected harmonic wave, rotational coordinates matrix need be made into formula (3):
（3）
Wherein, as n=3k-1, being positive sequence harmonic, as n=3k+1, is Negative sequence harmonic.
The PWM module of the present embodiment can be any pulse width modulation mode, such as SPWM, SVPWM, SHEPWM etc.
Meanwhile, the inverter of the present embodiment can be any inverter topology, as multi-electrical level inverters such as 2 flat inversion topologicals or diode clamp type, cascade, striding capacitance types.
The present embodiment also provides a kind of Active Power Filter-APF, and it comprises:
Gradation detection module 10, concentrated current loop controller 20, PWM module 30 and inverter 40, this gradation detection module 10, concentrated current loop controller 20, PWM module 30 and inverter 40 adopt Split moduleization to design.
Wherein, gradation detection module 10 is for needing to set the harmonic number of filtering and carrying out the detection of appointments subharmonic current in setting module according to the actual requirements.
Concentrate current loop controller 20 for receiving harmonic current, and carry out segmented centralized control according to the actual requirements, to eliminate the static difference that different harmonic frequency is brought.
PWM module 30 is for regulating the pulsewidth of harmonic current.
Inverter 40 is for becoming to need the harmonic current compensated by impulse waveform current conversion.
In actual applications; usually the fine degree of section can be set according to the actual requirements; and a gradation detection module 10 and a concentrated current loop controller 20 are set respectively in each interval; focus on so that in real time the harmonic current detected is sent into concentrate in current loop controller 20, effectively ensure that real-time and the accuracy of filtering.
In addition, PWM module 30 and inverter 40 can by the gradation detection module 10 of all sections and concentrated current loop controller 20 share (as shown in Figure 3), also a PWM module 30 and an inverter 40 can be set respectively in each interval, and the gradation detection module 10 in each interval, concentrated current loop controller 20, PWM module 30 are connected (as shown in Figure 4) successively with inverter 40.Certainly, in other embodiments of the present invention, the interval embodiment of PWM module 30 and inverter 40 can also have other form, will not enumerate herein.
After adopting said structure design, overall compensation process is, public CT is adopted to record load current, line voltage, be input to each interval corresponding module, the number of times of the harmonic current that the interval set according to the actual requirements comprises, several subharmonic currents adopting the appointment subharmonic detection algorithm based on Instantaneous Power Theory to calculate this interval to comprise.After the harmonic current in each interval superposes separately, to deliver in it corresponding Interval Set in current loop controller 20, obtain the instruction harmonic current that modules exports, then drive inverter 40 to export the required harmonic current compensated by PWM module 30 pulse signal obtaining corresponding to this module corresponding to each power switch pipe of inverter 40.
In sum, the present invention can overcome the system dynamic responding speed of FFT mode slow, based on Instantaneous Power Theory harmonic detecting technique existing for bandwidth problem and adopt the compensation precision problem of specifying existing for subharmonic current detection technique merely, equipment cost can be reduced again, the stability of elevator system.
The foregoing is only the preferred embodiments of the present invention; not thereby its scope of the claims is limited; every utilize specification of the present invention and accompanying drawing content to do equivalent structure or equivalent flow process conversion; directly or indirectly be used in the technical field that other are relevant, be all in like manner included in scope of patent protection of the present invention.
Claims (8)
1. an active power filtering method, is characterized in that, comprises the following steps:
Gather the three-phase current of load-side;
Obtain the electric current under fundamental frequency rotating coordinate system by coordinate transform, adopt the appointment subharmonic penalty method based on Instantaneous Power Theory to carry out sectional, gradation compensation to harmonic wave;
By current loop controller in offset current successively input set and PWM module, to convert impulse waveform electric current to;
Utilize and drive inverter to become to need the harmonic current compensated by described impulse waveform current conversion.
2. active power filtering method as claimed in claim 1, it is characterized in that, the step of the three-phase current of described collection load-side specifically comprises:
Set harmonic number according to the actual requirements and carry out appointment subharmonic current and detect.
3. active power filtering method as claimed in claim 1, it is characterized in that, the described electric current obtained by coordinate transform under fundamental frequency rotating coordinate system, adopts the step that appointment subharmonic penalty method carries out sectional to harmonic wave, gradation compensates based on Instantaneous Power Theory specifically to comprise:
After the change anglec of rotation and transformation matrix of coordinates obtain individual harmonic current, select the required harmonic current number of times compensated, be then added the harmonic current that just can obtain needing compensation.
4. active power filtering method as claimed in claim 3, is characterized in that, described by current loop controller in offset current successively input set and PWM module, specifically comprises with the step converting impulse waveform electric current to:
The number of times of the harmonic current that the interval set according to the actual requirements comprises, adopt and calculate based on the appointment subharmonic algorithm of Instantaneous Power Theory this few subharmonic current that this interval comprises, after the harmonic current in each interval is superposed separately, deliver in the concentrated current loop controller in interval corresponding with it, obtain the instruction harmonic current that modules exports, then drive inverter to export the required harmonic current compensated by the PWM module pulse signal obtaining corresponding to this module corresponding to each power switch pipe of inverter.
5. an Active Power Filter-APF, is characterized in that, comprising:
Gradation detection module, for needing to set the harmonic number of filtering and carrying out the detection of appointments subharmonic current in setting module according to the actual requirements;
Concentrating current loop controller, for receiving described harmonic current, and carrying out segmented centralized control according to the actual requirements, to eliminate the static difference that different harmonic frequency is brought;
PWM module, regulates the pulsewidth of harmonic current;
Inverter, for becoming to need the harmonic current compensated by described impulse waveform current conversion,
Described gradation detection module, concentrated current loop controller, PWM module and inverter adopt Split moduleization design.
6. Active Power Filter-APF as claimed in claim 5, is characterized in that, set section according to the actual requirements, arrange a gradation detection module and a concentrated current loop controller in each interval respectively.
7. Active Power Filter-APF as claimed in claim 6, is characterized in that, described PWM module and inverter by the gradation detection module of all sections and concentrated current loop controller share.
8. Active Power Filter-APF as claimed in claim 6, it is characterized in that, a PWM module and an inverter are set respectively in each interval, and the gradation detection module in each interval, concentrated current loop controller, PWM module are connected successively with inverter.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113067336A (en) * | 2021-05-18 | 2021-07-02 | 哈尔滨理工大学 | Three-level active filter based on model predictive control |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000050501A (en) * | 1998-08-03 | 2000-02-18 | Meidensha Corp | Reactive power compensating device |
| CN1402406A (en) * | 2002-09-06 | 2003-03-12 | 清华大学 | Active filter harmonic current test delay time compensation method and system |
| CN102255315A (en) * | 2010-05-17 | 2011-11-23 | 江苏方程电力科技有限公司 | Three-phase current balance adjustment system of electric energy adjusting and electricity saving device |
| CN102290815A (en) * | 2011-08-22 | 2011-12-21 | 湖北三环发展股份有限公司 | APF (active power filter) based on coupling inductance |
| CN102386622A (en) * | 2011-11-03 | 2012-03-21 | 东南大学 | Fully active harmonic control device combining full compensation and fractionated compensation of a plurality of machines |
-
2015
- 2015-09-15 CN CN201510586075.7A patent/CN105140923A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000050501A (en) * | 1998-08-03 | 2000-02-18 | Meidensha Corp | Reactive power compensating device |
| CN1402406A (en) * | 2002-09-06 | 2003-03-12 | 清华大学 | Active filter harmonic current test delay time compensation method and system |
| CN102255315A (en) * | 2010-05-17 | 2011-11-23 | 江苏方程电力科技有限公司 | Three-phase current balance adjustment system of electric energy adjusting and electricity saving device |
| CN102290815A (en) * | 2011-08-22 | 2011-12-21 | 湖北三环发展股份有限公司 | APF (active power filter) based on coupling inductance |
| CN102386622A (en) * | 2011-11-03 | 2012-03-21 | 东南大学 | Fully active harmonic control device combining full compensation and fractionated compensation of a plurality of machines |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113067336A (en) * | 2021-05-18 | 2021-07-02 | 哈尔滨理工大学 | Three-level active filter based on model predictive control |
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