CN201387450Y - Digital-analog hybrid harmonic analyzer - Google Patents
Digital-analog hybrid harmonic analyzer Download PDFInfo
- Publication number
- CN201387450Y CN201387450Y CN200920098898U CN200920098898U CN201387450Y CN 201387450 Y CN201387450 Y CN 201387450Y CN 200920098898 U CN200920098898 U CN 200920098898U CN 200920098898 U CN200920098898 U CN 200920098898U CN 201387450 Y CN201387450 Y CN 201387450Y
- Authority
- CN
- China
- Prior art keywords
- unit
- digital
- sampling
- analogue
- signal
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Measurement Of Current Or Voltage (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The utility model relates to a digital-analog hybrid harmonic analyzer. In the prior art, aiming at solving the fence effect and leaking phenomenon when the FFT algorithm is applied to harmonic analysis, a plurality of windowing and interpolating methods are provided, and under noise condition, even though the sampling is synchronous, the site use effect of the FFT algorithm is not ideal due to the influences of frequency spectrum leakage and modulating noise caused by sampling truncation effect of additive noise. The product comprises a sampling sensor and an auxiliary power supply module; the measured content is input into the sampling sensor which is connected with a conditioning unit module of a measuring main board; and the auxiliary power supply module is connected with the measuring main body which is connected with a keyboard and a liquid crystal display unit. The product is applied to real-time analysis, measurement of a power grid and harmonic component of non-liner electric appliances, masters the condition of harmonic content ratio in the power grid and is especially suitable for occasions containing additive noise and modulating noise.
Description
Technical field:
The utility model relates to a kind of digital-to-analogue and mixes harmonic analysis instrument.
Background technology:
Along with developing rapidly of Power Electronic Technique, nonlinear load increases sharply in the electrical network.Consumer is more and more serious to the interference of electrical network, cause that harmonic content increases rapidly in the electrical network, make the waveform generation distortion of voltage and current, this not only has a strong impact on power grid security and moves efficiently, and the reliability of the accuracy of electric parameter metering and instrument all reduces greatly.Measure the harmonic component of electrical network and non-linear electrical equipment in real time, the actual conditions of harmonic wave in the grasp system are very necessary for preventing harmonic wave harm, improving power supply quality.
The main method of harmonic wave on-line analysis, one is based on the mensuration of analog bandpass or rejection filter and detection; Two are based on the harmonic measure method of Fourier transform; Three are based on the harmonic measure method of instantaneous reactive power; Four are based on the measuring method of wavelet transformation; Five are based on the harmonic measure method of neural network.
Generally adopting digital measuring method now, wherein, is most widely used method based on the harmonic measure of Fourier transform, and its cardinal principle is Fast Fourier Transform (FFT).In order to solve fence effect and the leakage phenomenon that exists when fft algorithm is applied to frequency analysis, scholars have proposed the method for a lot of windowings and interpolation.Under noise situations, even sample-synchronous, because spectrum leakage and modularity The noise that the sampling truncation effect of additive noise produces, result of use is unsatisfactory at the scene to make above-mentioned fft algorithm.
Summary of the invention:
The purpose of this utility model is at the deficiency that reaches harmonic measure under the noise situations in the existing frequency analysis synchronously, provides a kind of digital-to-analogue to mix harmonic analysis instrument.
Above-mentioned purpose realizes by following technical scheme:
Digital-to-analogue is mixed harmonic analysis instrument; its composition comprises: sampling detector, accessory power supply module, measurement mainboard, keyboard and liquid crystal display; measured content is imported into described sampling detector; described sampling detector is connected with the conditioning unit module of measuring mainboard; described accessory power supply module is connected with the measurement mainboard, and described measurement mainboard is connected with keyboard and liquid crystal display.
Described digital-to-analogue is mixed harmonic analysis instrument, described measurement mainboard comprises conditioning unit module, program control frequency multiplication phase locking unit, digital-to-analogue mixing multiplication unit, low-pass filter unit, sample holding unit, multi pass acquisition unit and Single-chip Controlling unit, it is direct current+5 volt and ± 12 volts that described accessory power supply module will exchange 220 volts of power source conversion, for whole instrument provides direct supply; Described sampling detector is realized the sampling to measured signal; The conversion to measured signal is realized in described signal condition unit, and mixing multiplication unit for program control frequency multiplication phase locking unit and digital-to-analogue provides input signal; The N frequency-doubled signal that described program control frequency multiplication phase locking unit produces provides low order address for the ROM of digital-to-analogue mixed multiplier, the frequency N basis of phaselocked loop wants the overtone order of analysis to measure suitably selected, so that produce strict mutually orthogonal standard coS (k ω t), sin (k ω t) signal with frequency or harmonics; Described digital-to-analogue is mixed multiplication unit and is realized that measured signal Vx and cos (ω t), sin (ω t), cos (k ω t), sin (k ω t) multiply each other respectively, and multiplied result is respectively as the input of low-pass filter unit; Described low-pass filter unit carries out filtering to the output of above-mentioned digital-to-analogue mixed multiplier, extracts DC component, send sample holding unit; Described sample holding unit is realized sampling or is kept under the control of single-chip microcomputer; Sampling successively to the signal after keeping in described multi pass acquisition unit, and send the Single-chip Controlling unit to carry out data processing.
Described digital-to-analogue is mixed harmonic analysis instrument; following quadrinomial job is mainly finished in described Single-chip Controlling unit; the first provides the high address for the ROM of digital-to-analogue mixed multiplier; it two is to finish that sampling keeps and the control of multi pass acquisition; it three is Measurement and Data Processing, and it four is the control that realizes keyboard and liquid crystal display.
The beneficial effects of the utility model:
The utility model can be realized the optimal filtering method based on measurement of correlation, adopts the vector principle based on the analog digital mixed multiplier, and the method for the sine of first-harmonic and harmonic wave, cosine component synchronized sampling is carried out frequency analysis.Wherein, utilize the analog digital mixed multiplier to realize optimum correlation filtering, can be in the influence of filtering higher hamonic wave to greatest extent under the maximum signal noise ratio principle and additive noise; To the sine of first-harmonic and harmonic wave, the method for cosine component synchronized sampling, can eliminate of the influence of modularity noise to relative harmonic content and phase place.Thereby the comparatively ideal interference that overcomes the scene has solved the problem that exists in the frequency analysis, makes the frequency analysis result more accurate.Realize multiplying by hardware, the computed in software amount is few, has significantly reduced the software work amount.
Description of drawings:
Accompanying drawing 2 is circuit diagrams of the utility model part.
Accompanying drawing 3 is circuit diagrams of the utility model another part.
Accompanying drawing 4 is theory diagrams of the present utility model.
Embodiment:
Embodiment 1:
Digital-to-analogue is mixed harmonic analysis instrument, and its composition comprises: sampling detector, accessory power supply module, measurement mainboard, keyboard and liquid crystal display.Described sampling detector is advanced in measured input, and described sampling detector is connected with the signal condition unit module of measuring mainboard, and described accessory power supply module is connected with the measurement mainboard, and described measurement mainboard is connected with keyboard and liquid crystal display.
Described digital-to-analogue is mixed harmonic analysis instrument, and it is measured mainboard and comprises signal condition unit module, program control frequency multiplication phase locking unit, digital-to-analogue mixing multiplication unit, low-pass filter unit, sample holding unit, multi pass acquisition unit and Single-chip Controlling unit.
Described accessory power supply module adopts power transformer, rectifier bridge, wave filter, voltage stabilizer and filter capacitor etc., will exchange 220 volts of power source conversion and be direct current+5 volt with ± 12 volts, for whole instrument provides direct supply.
Described sampling detector employing voltage transformer (VT) (or current transformer) and amplifier sample circuit are realized the sampling to measured signal.
Described signal condition unit adopt to amplify and active power filtering etc. is realized conversion to measured signal, and mixing multiplication unit for program control frequency multiplication phase locking unit and digital-to-analogue provides input signal.
Described program control frequency multiplication phase locking unit is realized by field programmable gate function CPLD; the N frequency-doubled signal that produces provides low order address for the ROM of digital-to-analogue mixed multiplier; the frequency N basis of phaselocked loop wants the overtone order of analysis to measure suitably selected, so that produce strict mutually orthogonal standard cos (k ω t), sin (k ω t) signal with frequency or harmonics.
Described digital-to-analogue mixing multiplication unit is made of as core devices multiplication type D/A (D/A) converter of 8 bit parallels input; measured signal Vx is as the benchmark of D/A (D/A) converter; realize that measured signal Vx and cos (ω t), sin (ω t), cos (k ω t), sin (k ω t) multiply each other respectively, multiplied result is respectively as the input of low-pass filter unit.
Described low-pass filter unit is realized by active and passive filter, and filtering is carried out in the output of above-mentioned digital-to-analogue mixed multiplier, extracts DC component, send sample holding unit.
Described sample holding unit is made up of integrated sampling holder, realizes sampling or maintenance under the control of single-chip microcomputer.
Described multi pass acquisition unit is made up of multi-way switch and 4 half module/number converters (A/D), the signal after keeping is sampled successively, and send the Single-chip Controlling unit to carry out data processing.
Described Single-chip Controlling unit is by not forming with the single-chip microcomputer and the peripheral circuit of A/D converter (A/D); mainly finish following quadrinomial job; the first provides the high address for the ROM of digital-to-analogue mixed multiplier; it two is to finish that sampling keeps and the control of multi pass acquisition; it three is Measurement and Data Processing, and it four is the control that realizes keyboard and liquid crystal display.
Described keyboard and liquid crystal display adopt film key and lattice lcd display to form respectively, and they are worked in coordination, and realize setting, the control of measurement and the demonstration of measurement result of parameter.
Embodiment 2:
Digital-to-analogue is mixed harmonic analysis instrument, and its composition comprises: sampling detector, accessory power supply module, measurement mainboard, keyboard and liquid crystal display.Described sampling detector is advanced in measured input, and described sampling detector is connected with the signal condition unit module of measuring mainboard, and described accessory power supply module is connected with the measurement mainboard, and described measurement mainboard is connected with keyboard and liquid crystal display.
Described digital-to-analogue is mixed harmonic analysis instrument, and it is measured mainboard and comprises signal condition unit module, program control frequency multiplication phase locking unit, digital-to-analogue mixing multiplication unit, low-pass filter unit, sample holding unit, multi pass acquisition unit and Single-chip Controlling unit.
Described accessory power supply module adopts power transformer, rectifier bridge, wave filter, voltage stabilizer and filter capacitor etc., will exchange 220 volts of power source conversion and be direct current+5 volt with ± 12 volts, for whole instrument provides direct supply.
Described sampling detector employing voltage transformer (VT) (or current transformer) and amplifier sample circuit are realized the sampling to measured signal.
Described signal condition unit adopt to amplify and active power filtering etc. is realized conversion to measured signal, and mixing multiplication unit for program control frequency multiplication phase locking unit and digital-to-analogue provides input signal.
Described program control frequency multiplication phase locking unit is realized by field programmable gate function CPLD; the N frequency-doubled signal that produces provides low order address for the ROM of digital-to-analogue mixed multiplier; the frequency N basis of phaselocked loop wants the overtone order of analysis to measure suitably selected, so that produce strict mutually orthogonal standard cos (k ω t), sin (k ω t) signal with frequency or harmonics.
Described digital-to-analogue mixing multiplication unit is made of as core devices multiplication type D/A (D/A) converter of 10 bit parallels input; measured signal Vx is as the benchmark of D/A (D/A) converter; realize that measured signal Vx and cos (ω t), sin (ω t), cos (k ω t), sin (k ω t) multiply each other respectively, multiplied result is respectively as the input of low-pass filter unit.
Described low-pass filter unit is realized by active and passive filter, and filtering is carried out in the output of above-mentioned digital-to-analogue mixed multiplier, extracts DC component, send sample holding unit.
Described sample holding unit, multi pass acquisition unit and Single-chip Controlling unit and be one, single-chip microcomputer and peripheral circuit by band sampling holder, multi-way switch and 12 above A/D converters are formed, and realize functions such as sampling maintenance, signal sampling and data processing.
Described keyboard and liquid crystal display adopt film key and lattice lcd display to form respectively, and they are worked in coordination, and realize setting, the control of measurement and the demonstration of measurement result of parameter.
Embodiment 3:
Digital-to-analogue is mixed harmonic analysis instrument, and its composition comprises: sampling detector, accessory power supply module, measurement mainboard, keyboard and liquid crystal display.Described sampling detector is advanced in measured input, and described sampling detector is connected with the signal condition unit module of measuring mainboard, and described accessory power supply module is connected with the measurement mainboard, and described measurement mainboard is connected with keyboard and liquid crystal display.
Described digital-to-analogue is mixed harmonic analysis instrument, and it is measured mainboard and comprises signal condition unit module, program control frequency multiplication phase locking unit, digital-to-analogue mixing multiplication unit, low-pass filter unit, sample holding unit, multi pass acquisition unit and Single-chip Controlling unit.
It is direct current+5 volt and ± 12 volts that described accessory power supply module adopts switching power circuit will exchange 220 volts of power source conversion, for whole instrument provides direct supply.
Described sampling detector employing voltage transformer (VT) (or current transformer) and amplifier sample circuit are realized the sampling to measured signal.
Described signal condition unit adopt to amplify and active power filtering etc. is realized conversion to measured signal, and mixing multiplication unit for program control frequency multiplication phase locking unit and digital-to-analogue provides input signal.
Described program control frequency multiplication phase locking unit is realized by field programmable gate function CPLD; the N frequency-doubled signal that produces provides low order address for the ROM of digital-to-analogue mixed multiplier; the frequency N basis of phaselocked loop wants the overtone order of analysis to measure suitably selected, so that produce strict mutually orthogonal standard cos (k ω t), sin (k ω t) signal with frequency or harmonics.
Described digital-to-analogue mixing multiplication unit is made of as core devices multiplication type D/A (D/A) converter of 12 bit parallels input; measured signal Vx is as the benchmark of D/A (D/A) converter; realize that measured signal Vx and cos (ω t), sin (ω t), cos (k ω t), sin (k ω t) multiply each other respectively, multiplied result is respectively as the input of low-pass filter unit.
Described low-pass filter unit is realized by active and passive filter, and filtering is carried out in the output of above-mentioned digital-to-analogue mixed multiplier, extracts DC component, send sample holding unit.
Described sample holding unit, multi pass acquisition unit and Single-chip Controlling unit and be one, single-chip microcomputer and peripheral circuit by band sampling holder, multi-way switch and 12 above A/D converters are formed, and realize functions such as sampling maintenance, signal sampling and data processing.
Described keyboard and liquid crystal display adopt film key and lattice lcd display to form respectively, and they are worked in coordination, and realize setting, the control of measurement and the demonstration of measurement result of parameter.
Principle of work:
Utilize the analog digital mixed multiplier to realize optimum correlation filtering, can be in the influence of filtering higher hamonic wave to greatest extent under the maximum signal noise ratio principle and additive noise; Employing can be eliminated the influence of modularity noise to relative harmonic content and phase place to the sine of first-harmonic and harmonic wave, the method for cosine component synchronized sampling, thereby the comparatively ideal interference that overcomes the scene makes the frequency analysis result more accurate.By accompanying drawing 1 as seen, this harmonic analysis instrument is made up of four drive test amount passages, and wherein, two passages are used to measure the first-harmonic parameter, are referred to as the first-harmonic passage, and two passages are used to measure harmonic parameters in addition, are referred to as the harmonic wave passage.Subregion has the function table of cos (k ω t), sin (k ω t) among the ROM of the digital-to-analogue mixed multiplier of harmonic wave passage; subregion has cos (ω t), sin (ω t) function table that has the different mining number of samples in each cycle among the ROM of the digital-to-analogue mixed multiplier of first-harmonic passage, and the ROM subregion of first-harmonic passage is corresponding with the ROM subregion of harmonic wave passage.The high address is by Single-chip Controlling, to choose the Wave data of different subharmonic.ROM transmits the functional value of cos (k ω t), sin (k ω t) to the data terminal of multiplication type d/a converter, the reference voltage end Vref of D/A converter inserts measured signal u (t), is finished the digital analog mixed multiplying of standard signal cos (k ω t), sin (k ω t) Yu the simulating signal u (t) of digital quantity by multiplication type d/a converter.Through multiplying each other, after the filtering, obtaining direct current signal U
AkAnd U
Bk
The amplitude and the phase place that can get k subharmonic or first-harmonic thus are:
The course of work is finished.
Claims (2)
1. a digital-to-analogue is mixed harmonic analysis instrument; its composition comprises: sampling detector, accessory power supply module, measurement mainboard, keyboard and liquid crystal display; it is characterized in that: measured content is imported into described sampling detector; described sampling detector is connected with the conditioning unit module of measuring mainboard; described accessory power supply module is connected with the measurement mainboard, and described measurement mainboard is connected with keyboard and liquid crystal display.
2. digital-to-analogue according to claim 1 is mixed harmonic analysis instrument, it is characterized in that: described measurement mainboard comprises conditioning unit module, program control frequency multiplication phase locking unit, digital-to-analogue mixing multiplication unit, low-pass filter unit, sample holding unit, multi pass acquisition unit and Single-chip Controlling unit, it is direct current+5 volt and ± 12 volts that described accessory power supply module will exchange 220 volts of power source conversion, for whole instrument provides direct supply; Described sampling detector is realized the sampling to measured signal; The conversion to measured signal is realized in described signal condition unit, and mixing multiplication unit for program control frequency multiplication phase locking unit and digital-to-analogue provides input signal; The N frequency-doubled signal that described program control frequency multiplication phase locking unit produces provides low order address for the ROM of digital-to-analogue mixed multiplier, the frequency N basis of phaselocked loop wants the overtone order of analysis to measure suitably selected, so that produce strict mutually orthogonal standard cos (k ω t), sin (k ω t) signal with frequency or harmonics; Described digital-to-analogue is mixed multiplication unit and is realized that measured signal Vx and cos (ω t), sin (ω t), cos (k ω t), sin (k ω t) multiply each other respectively, and multiplied result is respectively as the input of low-pass filter unit; Described low-pass filter unit carries out filtering to the output of above-mentioned digital-to-analogue mixed multiplier, extracts DC component, send sample holding unit; Described sample holding unit is realized sampling or is kept under the control of single-chip microcomputer; Sampling successively to the signal after keeping in described multi pass acquisition unit, and send the Single-chip Controlling unit to carry out data processing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200920098898U CN201387450Y (en) | 2009-01-13 | 2009-01-13 | Digital-analog hybrid harmonic analyzer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200920098898U CN201387450Y (en) | 2009-01-13 | 2009-01-13 | Digital-analog hybrid harmonic analyzer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201387450Y true CN201387450Y (en) | 2010-01-20 |
Family
ID=41579985
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200920098898U Expired - Fee Related CN201387450Y (en) | 2009-01-13 | 2009-01-13 | Digital-analog hybrid harmonic analyzer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201387450Y (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102508028A (en) * | 2011-10-10 | 2012-06-20 | 江苏科技大学 | Device and method for detecting and analyzing harmonic |
| CN103592514A (en) * | 2012-08-15 | 2014-02-19 | 王景芳 | Novel harmonic high-precision detection method |
| CN103913654A (en) * | 2014-03-17 | 2014-07-09 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Method and device for identifying fault feature of grounding electrode of high-voltage direct-current transmission system |
| CN107607821A (en) * | 2017-10-25 | 2018-01-19 | 广西电网有限责任公司电力科学研究院 | A kind of controllable middle pressure XLPE cable ageing test apparatus of harmonic content |
| CN108345935A (en) * | 2017-01-25 | 2018-07-31 | 株式会社东芝 | Product and arithmetic unit, network element and network equipment |
-
2009
- 2009-01-13 CN CN200920098898U patent/CN201387450Y/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102508028A (en) * | 2011-10-10 | 2012-06-20 | 江苏科技大学 | Device and method for detecting and analyzing harmonic |
| CN103592514A (en) * | 2012-08-15 | 2014-02-19 | 王景芳 | Novel harmonic high-precision detection method |
| CN103913654A (en) * | 2014-03-17 | 2014-07-09 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Method and device for identifying fault feature of grounding electrode of high-voltage direct-current transmission system |
| CN108345935A (en) * | 2017-01-25 | 2018-07-31 | 株式会社东芝 | Product and arithmetic unit, network element and network equipment |
| CN107607821A (en) * | 2017-10-25 | 2018-01-19 | 广西电网有限责任公司电力科学研究院 | A kind of controllable middle pressure XLPE cable ageing test apparatus of harmonic content |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100489555C (en) | Universal electric power mutual-inductor verification device | |
| CN101807795B (en) | Method for forming electric energy metering simulation system and device thereof | |
| CN201387450Y (en) | Digital-analog hybrid harmonic analyzer | |
| CN104237622B (en) | The method of sampling and wideband voltage/calibration of power device based on software based frequency tracking | |
| CN102662106B (en) | Method for measuring electric energy of harmonic power network | |
| CN105866543B (en) | It is a kind of eliminate fundamental wave, harmonic wave to m-Acetyl chlorophosphonazo detection interference harmonic detection method | |
| CN108318852A (en) | A kind of intelligent electric energy meter square wave influence test method | |
| CN102175921A (en) | Portable impedance measurement instrument based on FPGA (field programmable gate array) | |
| Dirik et al. | A computation and metering method for harmonic emissions of individual consumers | |
| Arenas et al. | A methodology for power quantities calculation applied to an FPGA-based smart-energy meter | |
| Bucci et al. | Embedded power and energy measurement system based on an analog multiplier | |
| CN104090177A (en) | Power network operation data intelligent test analyzer | |
| CN104155521A (en) | Method and apparatus for determining phase difference | |
| CN205049724U (en) | Sky device is put to electric current of transformer core earth current on -line monitoring equipment | |
| CN103176030A (en) | Method for detecting inter-harmonics of power distribution system | |
| CN205038242U (en) | A signal generating device for electric power system live test instrument check -up usefulness | |
| CN203881861U (en) | Multifunctional power grounding parameter tester | |
| Gao et al. | A low consumption DSP based power analyzer | |
| Sefa et al. | Power quality analyzer for three phase systems | |
| Medeiros et al. | A low cost power quality meter over the internet | |
| Mittal et al. | Implementing Digital Filters and DSP Micro-Controller for Estimating the Frequency of a Time-Domain Signal | |
| Guia et al. | Design and Implementation of Real Time RMS Measurement System based on Wavelet Transform Using adsPIC-type Microcontroller | |
| CN105203843B (en) | The average first phase position detecting method and system of electric power signal | |
| CN107525965B (en) | Power analysis method and device | |
| CN112763969B (en) | Device and method for detecting field harmonic electric energy metering error |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20100120 Termination date: 20120113 |