CN106877334A - A kind of harmonic detecting compensation device based on FPGA - Google Patents
A kind of harmonic detecting compensation device based on FPGA Download PDFInfo
- Publication number
- CN106877334A CN106877334A CN201710189373.1A CN201710189373A CN106877334A CN 106877334 A CN106877334 A CN 106877334A CN 201710189373 A CN201710189373 A CN 201710189373A CN 106877334 A CN106877334 A CN 106877334A
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- Prior art keywords
- fpga
- harmonic
- device based
- compensation device
- harmonic detecting
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Classifications
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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
-
- 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
-
- 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
- H02J3/18—Arrangements for adjusting, eliminating or compensating reactive power in networks
- H02J3/1821—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators
-
- 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
- Y02E40/30—Reactive power compensation
-
- 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
- Y02E40/40—Arrangements for reducing harmonics
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- General Physics & Mathematics (AREA)
- Inverter Devices (AREA)
Abstract
The invention discloses a kind of harmonic detecting compensation device based on FPGA, it is therefore intended that, improve conversion speed and accuracy, improve system real-time, preferably realize suppress harmonic wave purpose, the technical scheme for being used for：Including harmonic compensation cabinet, current closed-loop control circuit is provided between power supply and load in harmonic compensation cabinet, the current closed-loop control circuit is using 4 staggered samplings in parallel, the current closed-loop control circuit includes the wave filter being sequentially connected electrically, input contactor, inductance, IGBT inverters, first pi regulator and coordinate transformation module, coordinate transformation module is respectively electrically connected to IGBT inverters and load, the load and wave filter are connected to power supply, the second pi regulator and PWM generator have been sequentially connected electrically between the coordinate transformation module and IGBT inverters, the harmonic detecting module based on FPGA parallel with one another and phaselocked loop are provided between the coordinate transformation module and load.
Description
Technical field
The present invention relates to a kind of power equipment, and in particular to a kind of harmonic detecting compensation device based on FPGA.
Background technology
With developing rapidly for China's economy and power industry, electric load species is various all the more, and power load is increasingly multiple
Hydridization and variation.The change harmonic wave of generation of the waveform of alternating current brings serious harm to electric power users, power system,
Current that this harm is referred to as harmonic pollution, harmonic pollution has become harm power network, influences other electrical equipment safety
The significant problem of economical operation.Electric harmonic is an important indicator for reflecting dynamical system quality of power supply quality, harmonic components
Number, reflect voltage and current actual waveform deviate rationality waveform intensity of variation.Conventional harmonic measuring method is main
Have：Analog bandpass or bandstop filter measurement harmonic wave；Harmonic measure based on instantaneous reactive power, but, various basic skills
There are limitation and shortcoming in various degree in practice, so as to there is also the potential safety hazard of electricity usage.
The content of the invention
In order to solve the problems of the prior art, the present invention proposes a kind of harmonic detecting compensation device based on FPGA, tool
Have the advantages that conversion speed is fast and accuracy is high, improve the real-time of system, preferably realize the purpose for suppressing harmonic wave.
In order to realize the above object the technical solution adopted in the present invention is：Including harmonic compensation cabinet, harmonic compensation cabinet
Be provided with current closed-loop control circuit between internal power supply and load, the current closed-loop control circuit using 4 it is staggered simultaneously
Connection sampling, the current closed-loop control circuit include be sequentially connected electrically wave filter, input contactor, inductance, IGBT inverters,
First pi regulator and coordinate transformation module, coordinate transformation module are respectively electrically connected to IGBT inverters and load, the load
Be connected to power supply with wave filter, be sequentially connected electrically between the coordinate transformation module and IGBT inverters the second pi regulator and
PWM generator, is provided with harmonic detecting module and lock phase based on FPGA parallel with one another between the coordinate transformation module and load
Ring.
The harmonic detecting module includes transformer and control system, and it is mono- that control system is connected with A/D change-over circuits, FIFO
Unit, the FFT unit based on FPGA, memory cell, upper communication module and interactive unit, the transformer, A/D change-over circuits,
Cell fifo and the FFT unit based on FPGA are sequentially connected electrically；Phase demodulating, frequency doubling is provided between the control system and transformer
Circuit.
The control system uses the control systems of DSP 2407.
The upper communication module uses RS485 standard interfaces.
The memory cell uses EEPROM.
The interactive unit includes keyboard and display.
The transformer includes voltage transformer pt summation current transformer CT.
Soft start resistance is parallel with the input contactor.
The wave filter uses high-pass filter.
The IGBT inverters use three-phase half-bridge inverter.
Compared with prior art, current closed-loop control circuit of the present invention is using 4 staggered samplings in parallel；In load current stream
Harmonic detecting is carried out through setting the harmonic detecting module based on FPGA on the loop of IGBT inverters, by obtaining detection signal,
Signal conversion is carried out using control system control, the amplitude and phase angle of each harmonic of reentrying.The present invention uses quasi- Natural Sampling,
Control and modulating frequency 500KHz, because the frequency using 4 staggered parallel connections, total current can reach 64.8KHz, such electric current
The width of ring can be beaten and greatly improve；The control method of electric current loop uses total current control ring and branch current error control loop knot
Close, the bandwidth of branch current error control loop can be with lower, for controlling to flow.Control algolithm take into account stable state compensation precision and
The rapidity of compensation, for reactive-load compensation, using opened loop control, the compensation response time is less than 10ms；For harmonic compensation, use
Closed-loop control, THDi is less than 3% after compensation, can also realize it is idle with harmonic wave while compensation, respectively compensation, to specifying subharmonic
Orientation compensation；Total current and single harmonic component can set cut-off current, make device not excessively stream.Essentially eliminate because excessively stream causes out
The possibility that pipe is damaged is closed, the reliability of device is enhanced.Current close-loop control system can the electricity that sends of the automatic detection present apparatus
The difference of stream and given electric current, and by the parameter of changed number wave filter, autonomous calibration reference current controls to join from main modulation
Number, so that suppression system resonance, the stability of strengthening system.Conversion speed of the present invention is fast, and accuracy is high, significantly improves system
Real-time, realize preferably suppress harmonic wave purpose.
Further, after system start completion each unit is initialized, the voltage and electricity to be detected are obtained by mutual inductor unit
Stream signal, and a wherein phase voltage signal is utilized, the work frequency of real-time power circuit is tracked through phase demodulating, frequency doubling synchronous circuit,
And by frequency-doubled signal, micro treatment control system is obtained the accurate signal of A/D conversions, control A/D change-over circuits are in a work
Accurate synchronization carries out signal conversion in the frequency cycle, and transformation result caches in entering cell fifo, after control point is reached, microprocessor
Controller control stops conversion, starts FPGA and data are read from cell fifo, then by the FFT unit based on FPGA, complete letter
Number conversion, obtain each harmonic amplitude and phase angle.After EOC, analysis result is read by micro treatment control system, deposited
It is stored in EEPROM cell, system also can in real time show analysis result, and be directly accessed electric power dispatching network by communication interface, it is real
The upload of existing analysis result receives remote dispatching.
Further, input to be touched and be parallel with soft start resistance on device KM；During system boot, power supply is by resistance R to bus
Electric capacity charges, and implements bus soft start.
Further, wave filter uses high-pass filter, filters the switching harmonics of inverter.
Further, inverter uses three-phase half-bridge inverter, is made up of IGBT module, and IGBT is MOSFET and bipolar transistor
Pipe meets device.The characteristics of its existing MOSFET easily drives, and have the advantages that power crystal tube voltage, Capacitive Flow are big.
Its frequency characteristic, can be with normal work in tens KHz frequency ranges between MOSFET and power transistor.
Brief description of the drawings
Fig. 1 is structural representation of the invention；
Fig. 2 is harmonic detecting modular structure schematic diagram.
Specific embodiment
The present invention is further explained with reference to specific embodiment and Figure of description.
Referring to Fig. 1, the present invention includes harmonic compensation cabinet, and electricity is provided between the power supply and load in harmonic compensation cabinet
Stream closed control circuit, current closed-loop control circuit includes electricity successively using 4 staggered samplings in parallel, current closed-loop control circuit
The wave filter of connection, input contactor KM, inductance L, IGBT inverter, the first pi regulator PI1With coordinate transformation module C2r/
3s, coordinate transformation module C2r/3s are respectively electrically connected to IGBT inverters and load, and load and wave filter are connected to power supply, coordinate
The second pi regulator PI has been sequentially connected electrically between conversion module C2r/3s and IGBT inverter2And PWM generator, coordinate transform mould
The harmonic detecting module based on FPGA parallel with one another and phase-locked loop pll are provided between block C2r/3s and load.Transformer CT/PT bags
Voltage transformer pt summation current transformer CT is included, for detection voltage and current signal；Soft opening is parallel with input contactor KM
Dynamic resistance R, wave filter uses high-pass filter, IGBT inverters to use three-phase half-bridge inverter.
Referring to Fig. 2, harmonic detecting module includes transformer CT/PT and control system, and control system is connected with A/D conversion electricity
Road, cell fifo, the FFT unit based on FPGA, memory cell, upper communication module and interactive unit, the transformer CT/
PT, A/D change-over circuit, cell fifo and the FFT unit based on FPGA are sequentially connected electrically；The control system and transformer CT/
Phase demodulating, frequency doubling circuit is provided between PT.Control system uses the control systems of DSP 2407, for the control of signal conversion；It is upper
Communication module uses RS485 standard interfaces, for realizing being connected the information after treatment and outer accessory system, is marked using RS485
Quasi- interface can expand the applicability and the scope of application of the present apparatus；Memory cell uses EEPROM, by EEPROM memory module realities
The quick storage of existing data or reading；Interactive unit includes keyboard and display, for harmonic detecting module input control letter
Breath, while showing analysis result in real time.
Referring to Fig. 1, the present invention includes harmonic compensation cabinet, and electricity is provided between the power supply and load in harmonic compensation cabinet
Stream closed control circuit；Current closed-loop control circuit includes IGBT inverters；Current closed-loop control circuit using 4 it is staggered simultaneously
Connection sampling；The harmonic detecting module based on FPGA is provided with the loop that load current flows through IGBT inverters.Using standard certainly
So sampling, control and modulating frequency 500KHz, because the frequency using 4 staggered parallel connections, total current can reach 64.8KHz,
So the width of electric current loop can be beaten and greatly improve；The control method of electric current loop uses total current control ring and branch current error
Control ring is combined, and the bandwidth of branch current error control loop can be with lower, for controlling to flow.Control algolithm takes into account stable state benefit
The rapidity of precision and compensation is repaid, for reactive-load compensation, using opened loop control, the compensation response time is less than 10ms；For harmonic wave
Compensation, using closed-loop control, after compensation THDi be less than 3%, can also realize it is idle with harmonic wave while compensation, respectively compensate, it is right
Specify the orientation compensation of subharmonic；Total current and single harmonic component can set cut-off current, make device not excessively stream.Essentially eliminate because
Excessively stream causes the possibility that switching tube is damaged, and enhances the reliability of device.Current close-loop control system can automatic detection this dress
Put the difference of the electric current and given electric current for sending, and by the parameter of changed number wave filter, autonomous calibration reference current, independently
Adjustment control parameter, so that suppression system resonance, the stability of strengthening system.
Referring to Fig. 2, the harmonic detecting module based on FPGA of the invention includes transformer, control system, and is with control
A/D change-over circuits, cell fifo, the FFT unit of FPGA, memory cell, upper communication module and interactive unit that system is electrically connected；
The FFT unit of transformer, A/D change-over circuits, cell fifo and FPGA is sequentially connected electrically；Between the control system and transformer
It is provided with phase demodulating, frequency doubling circuit.Upper communication module uses RS485 standard interfaces；For being by the information after treatment and outer auxiliary
System realizes connection, and the applicability and the scope of application of the present apparatus can be expanded using RS485 standard interfaces.Control system is used
DSP2407 control systems, for the control of signal conversion.Memory cell uses EEPROM；Realized by EEPROM memory modules
The quick storage of data or reading.Interactive unit includes keyboard and display；For being input into control information to harmonic detecting module,
Show analysis result in real time simultaneously.Transformer includes voltage transformer pt summation current transformer CT；For detection voltage and electric current
Signal.After system start completion each unit is initialized, 3 phase voltages to be detected are obtained by CT/PT sensor units mutually electric with 3
Stream signal, and a wherein phase voltage signal is utilized, the work frequency of real-time power circuit is tracked through phase demodulating, frequency doubling synchronous circuit,
And by frequency-doubled signal, micro treatment control system is obtained the accurate signal of A/D conversions, control A/D change-over circuits are in a work
14 that carry out 6 road signals conversions of accurate synchronization in the frequency cycle, transformation result is cached in entering FIFO, micro- after 128 point is gathered
Processing controller control stops conversion, starts FPGA and data are read from FIFO, then by the FFT unit based on FPGA, complete 128
The conversion of 6 road signals of point, obtains the amplitude and phase angle of each harmonic.After EOC, read by micro treatment control system and divided
Analysis result, is stored in EEPROM cell, and system also can in real time show analysis result, or by RS485 standard interfaces, by standard
IEC60870-5-103 stipulations are directly accessed electric power dispatching network, realize the upload of analysis result or receive remote dispatching.
Claims (10)
1. a kind of harmonic detecting compensation device based on FPGA, it is characterised in that including harmonic compensation cabinet, harmonic compensation cabinet
Current closed-loop control circuit is provided between interior power supply and load, the current closed-loop control circuit uses 4 staggered parallel connections
Sampling, wave filter that the current closed-loop control circuit includes being sequentially connected electrically, input contactor (KM), inductance (L), IGBT are inverse
Become device, the first pi regulator (PI1) and coordinate transformation module (C2r/3s), coordinate transformation module (C2r/3s) is respectively electrically connected to
IGBT inverters and load, the load and wave filter are connected to power supply, and the coordinate transformation module (C2r/3s) and IGBT are inverse
The second pi regulator (PI has been sequentially connected electrically between becoming device2) and PWM generator, the coordinate transformation module (C2r/3s) and load
Between be provided with the harmonic detecting module based on FPGA parallel with one another and phaselocked loop (PLL).
2. a kind of harmonic detecting compensation device based on FPGA according to claim 1, it is characterised in that the harmonic wave inspection
Surveying module includes transformer (CT/PT) and control system, and control system is connected with A/D change-over circuits, cell fifo, based on FPGA
FFT unit, memory cell, upper communication module and interactive unit, the transformer (CT/PT), A/D change-over circuits, FIFO
Unit and the FFT unit based on FPGA are sequentially connected electrically；Phase demodulation times is provided between the control system and transformer (CT/PT)
Frequency circuit.
3. a kind of harmonic detecting compensation device based on FPGA according to claim 2, it is characterised in that the control system
System uses the control systems of DSP 2407.
4. a kind of harmonic detecting compensation device based on FPGA according to claim 2, it is characterised in that described upper logical
News module uses RS485 standard interfaces.
5. a kind of harmonic detecting compensation device based on FPGA according to claim 2, it is characterised in that the storage list
Unit uses EEPROM.
6. a kind of harmonic detecting compensation device based on FPGA according to claim 2, it is characterised in that the interaction is single
Unit includes keyboard and display.
7. a kind of harmonic detecting compensation device based on FPGA according to claim 2, it is characterised in that the transformer
(CT/PT) voltage transformer pt summation current transformer CT is included.
8. a kind of harmonic detecting compensation device based on FPGA according to claim 1, it is characterised in that the input connects
Soft start resistance (R) is parallel with tentaculum (KM).
9. according to a kind of harmonic detecting compensation device based on FPGA described in claim 1, it is characterised in that the wave filter is adopted
Use high-pass filter.
10. according to a kind of harmonic detecting compensation device based on FPGA described in claim 1, it is characterised in that the IGBT is inverse
Become device and use three-phase half-bridge inverter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710189373.1A CN106877334A (en) | 2017-03-27 | 2017-03-27 | A kind of harmonic detecting compensation device based on FPGA |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710189373.1A CN106877334A (en) | 2017-03-27 | 2017-03-27 | A kind of harmonic detecting compensation device based on FPGA |
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| CN106877334A true CN106877334A (en) | 2017-06-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201710189373.1A Pending CN106877334A (en) | 2017-03-27 | 2017-03-27 | A kind of harmonic detecting compensation device based on FPGA |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107505506A (en) * | 2017-08-08 | 2017-12-22 | 武汉理工大学 | Electrical Propulsion Ship Harmonics Monitoring System based on FPGA and DSP |
| CN111426875A (en) * | 2020-03-23 | 2020-07-17 | 南京国电南自电网自动化有限公司 | Electrical frequency spectrum monitoring device and method |
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| CN2779702Y (en) * | 2005-01-21 | 2006-05-10 | 浙江大学 | An active power filter based on mixed type harmonic detection |
| CN103683290A (en) * | 2013-12-17 | 2014-03-26 | 深圳市三和电力科技有限公司 | Parallel connection type active power filter |
| CN204732876U (en) * | 2015-07-08 | 2015-10-28 | 扬州北辰通用智能电网有限公司 | Based on the intelligent active power filter device of inverse system |
| CN205646824U (en) * | 2016-05-26 | 2016-10-12 | 萨顿斯（上海）电源有限公司 | Novel active electric power filter |
| CN106877326A (en) * | 2015-12-13 | 2017-06-20 | 申久祝 | Active Power Filter-APF New type of current control method |
-
2017
- 2017-03-27 CN CN201710189373.1A patent/CN106877334A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2779702Y (en) * | 2005-01-21 | 2006-05-10 | 浙江大学 | An active power filter based on mixed type harmonic detection |
| CN103683290A (en) * | 2013-12-17 | 2014-03-26 | 深圳市三和电力科技有限公司 | Parallel connection type active power filter |
| CN204732876U (en) * | 2015-07-08 | 2015-10-28 | 扬州北辰通用智能电网有限公司 | Based on the intelligent active power filter device of inverse system |
| CN106877326A (en) * | 2015-12-13 | 2017-06-20 | 申久祝 | Active Power Filter-APF New type of current control method |
| CN205646824U (en) * | 2016-05-26 | 2016-10-12 | 萨顿斯（上海）电源有限公司 | Novel active electric power filter |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107505506A (en) * | 2017-08-08 | 2017-12-22 | 武汉理工大学 | Electrical Propulsion Ship Harmonics Monitoring System based on FPGA and DSP |
| CN111426875A (en) * | 2020-03-23 | 2020-07-17 | 南京国电南自电网自动化有限公司 | Electrical frequency spectrum monitoring device and method |
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