CN104502686A - Method for detecting three-phase electric parameter - Google Patents
Method for detecting three-phase electric parameter Download PDFInfo
- Publication number
- CN104502686A CN104502686A CN201410814383.6A CN201410814383A CN104502686A CN 104502686 A CN104502686 A CN 104502686A CN 201410814383 A CN201410814383 A CN 201410814383A CN 104502686 A CN104502686 A CN 104502686A
- Authority
- CN
- China
- Prior art keywords
- detection method
- chip
- reactive power
- register
- power
- 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.)
- Pending
Links
Abstract
The invention discloses a method for detecting a three-phase electric parameter. A single chip microcomputer is adopted and is provided with a voltage and current signal acquirer and an electric energy metering chip. When the detection method is used for processing a voltage signal and a current signal, on the premise that active power is not changed, compensation can be made for reactive power of harmonic waves in a detected system; an A/D (analog/digital) signal of the three-phase electric parameter can be analyzed by laplace transformation, and the voltage signal and the current signal are precisely calculated and acquired by combining zero point and pole point analysis of a time domain and a complex frequency domain; the single chip microcomputer adopts an STM32F103VET6 chip based on a Cortex-M3 kernel as a main chip. On the premise that the measurement precision is not affected, the computing speed of a system is considered, and the cost of the system is reduced; the reactive power of the harmonic waves in the system can be compensated, and the obtained three-phase electric parameter is scientifically acquired and processed.
Description
Technical field
The present invention relates to technical field of electric power detection, especially relate to a kind of three phase electrical parameters detection method.
Background technology
In prior art, the detection method of three phase electrical parameters mainly contains following several: one is the voltage and current signal utilizing voltage transformer (VT) summation current transformer to collect three phase electrical parameters, then the small-signal obtained is passed through special electric energy computation chip, computation chip transfers data to single-chip microcomputer after calculating, and the data of single-chip microcomputer conformity calculation gained also show; Two is by direct for voltage signal dividing potential drop access A/D chip (modulus conversion chip), draw real-time voltage value, the data of acquisition are passed through current-voltage conversion circuit by current transformer by electric current, again by A/D chip, draw real-time current numerical value, finally the data of gained are transferred to single-chip microcomputer, single-chip microcomputer process data also show; Three is be utilize current transformer and voltage transformer (VT) collection signal equally, then transfers data to dsp chip (digital signal processing chip), directly carries out digital processing;
The main Problems existing of above-mentioned three phase electrical parameters detection method has: one is because three-phase electricity needs the parameter of measurement numerous, do not use the words of special electric energy computation chip, the part calculated in system software can be very complicated, and the precision calculated also remains to be discussed, special electric energy computation chip is used also to there is the accuracy of measuring of computation chip and the impact of error in dipping, and for the problem how numerical value that computation chip provides correctly utilizes; Two is calculate relative to use dsp chip, use the cost of single-chip microcomputer much lower, but the computing velocity of common single-chip microcomputer is difficult to meet the demands; Three is that prior art all just rests on the simple active power reading electric energy chip numerical value or calculate first-harmonic to the research of three-phase electricity, does not have enough concerns and process to the harmonic wave of system;
Harmonic wave refers to the periodic voltage of any frequency except basic frequency (50Hz), current signal, very serious in the harm of Harmonic in Power System, harmonic wave makes the generation of electric energy, transmission and the efficiency utilized reduce, make apparatus overheat, produce vibration & noise, and make insulation ag(e)ing, make the lost of life, even break down or burn, harmonic wave can cause electric system local parallel resonant or series resonance, harmonic content is amplified, cause the equipment burnouts such as capacitor, harmonic wave also can cause relay protection and aut.eq. maloperation, electric energy metrical is caused confusion, outside for electric system, harmonic wave can produce severe jamming to communication facilities and electronic equipment.
Summary of the invention
The present invention is to solve existing three phase electrical parameters detection method Problems existing, under a kind of prerequisite not affecting measuring accuracy is provided, the cost of system is reduced while taking into account system operations speed, compensation is made to the reactive power of the harmonic wave in system, the three phase electrical parameters detection method of science acquisition and processing parameter.
To achieve these goals, the present invention is by the following technical solutions: a kind of three phase electrical parameters detection method, adopt single-chip microcomputer, single-chip microcomputer is provided with voltage, current signal collector, electric energy computation chip, described detection method is to voltage, when current signal processes, under the prerequisite that active power is constant, reactive power for the harmonic wave in detected system makes compensation, described detection method also adopts the A/D signal of Laplace transform to three phase electrical parameters to analyze, and in conjunction with time domain, the zero point of complex frequency domain two aspect, Poles Analysis, to voltage, current signal carries out accurate Calculation and collection.The surveying instrument of this programme has 232 conventional communication interfaces for user, also facilitates the debugging of system; According to the harmonic wave reactive power calculating the gain of parameter system gathered, testing result is compensated; This programme uses the A/D signal of method to three-phase electricity number of Laplace transform to analyze, Laplace transform is that the function of time is transformed to function of a complex variable, or do vice versa, at this moment, though time domain variable t is real number, variable s in complex frequency domain function is but plural number, from physical significance, relative to Fourier transform, frequency w is transformed to complex frequency domain s by Laplce, w can only describe the repetition frequency of vibration, and s can not only provide repetition frequency, can also represent growth rate or the rate of decay of oscillation amplitude.
As preferably, described single-chip microcomputer adopts STM32F103VET6 chip based on Cortex-M3 kernel as master chip, and described electric energy computation chip is provided with power excursion register, temperature register, First Harmonic Reactive Power register, temperature drift register.This programme uses and carrys out computation and measurement three phase electrical parameters based on Cortex-M3 kernel STM32F103VET6 high end chip as master chip, due to the feature such as this chip high speed, low-power consumption, structure be simple, break away from conventional one-piece electromechanical parameters measuring method precision not high enough, the problem that parallel processing capability is weak, lower again relative to the design cost of dsp chip, substantially increase arithmetic speed in addition; Power excursion register: can, by the error to the chip of the write update the system of power excursion register, make the measured value of system more accurate; Temperature register: record temperature value at that time while reading data, carries out different temperature compensations according to different temperature to the measurement data of instrument, by the numerical value write temperature drift register compensated; First Harmonic Reactive Power register: can indirectly obtain harmonic wave reactive power numerical value by the value of this register, and then the reactive power of analytic system is on the impact of system; Temperature drift register: by necessary correction can be carried out to the temperature variant phenomenon of system to the write of this register.
As preferably, the reactive power of described detection method to the harmonic wave in detected system compensates and comprises: 1) by calculating the harmonic wave reactive power obtaining detected system, 2) carry out reactive-load compensation by shnt capacitor.There is applied power (S), active power (P), reactive power (Q), system First Harmonic Reactive Power (Q in general electric system to be detected
b), wherein there is following relation between S, P, Q, can represent by rate right-angle triangle hard, two right-angle sides are respectively Q and P, hypotenuse is the included angle between S, S and P is power-factor angle, it reflects the phase differential between voltage and current in this alternating circuit, in this programme, first obtaining applied power by real-time voltage electric current, is numerically the product of voltage and current in alternating circuit, the then active power of reading system, by the reactive power of power triangle computing system, i.e. Q
2=S
2-P
2, then deduct the reactive power of system first-harmonic, finally obtain the harmonic wave reactive power Q of system
x=Q-Q
b; Obtain Q
xafter, utilize the principle of reactive-load compensation, compensated by shnt capacitor, the ultimate principle of reactive-load compensation is: having the device of capacitive power load and inductive load and being connected in same circuit, energy mutually exchanges between two kinds of loads, like this, the reactive power compensation that the reactive power required for inductive load can be exported by capacitive load; The selection of shnt capacitor installed capacity, according to the difference of application target, by improving power factor, can improve working voltage and reduction line loss etc. because usually determining, easy, clear and definite by the method improving power factor determination compensation capacity, by general both at home and abroad.
As preferably, described detection method, by repeatedly reading electric energy computation chip internal reference numerical value in the unit interval, obtains mean value after summation.Momentary current, voltage, power, these parameters can directly read from the register of electric energy computation chip, owing to being instantaneous value, in register, data can be different because of different picking rates, for the purpose of accurately, repeatedly can read the numerical value of register, then summation is averaged, and obtains exact value.
Therefore, the present invention has following beneficial effect: (1), under the prerequisite not affecting measuring accuracy, reduces the cost of system while taking into account system operations speed; (2) compensation is made to the reactive power of the harmonic wave in system; (3) three phase electrical parameters that obtains of science acquisition and processing.
Accompanying drawing explanation
Fig. 1 is a kind of principle schematic of the present invention.
Fig. 2 is power triangle schematic diagram of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the present invention will be further described.
A kind of three phase electrical parameters detection method, principle as shown in Figure 1, adopt single-chip microcomputer, single-chip microcomputer is provided with voltage, current signal collector, electric energy computation chip, detection method is to voltage, when current signal processes, under the prerequisite that active power is constant, reactive power for the harmonic wave in detected system makes compensation, detection method also adopts the A/D signal of Laplace transform to three phase electrical parameters to analyze, and in conjunction with time domain, the zero point of complex frequency domain two aspect, Poles Analysis, to voltage, current signal carries out accurate Calculation and collection, single-chip microcomputer adopts based on the STM32F103VET6 chip of Cortex-M3 kernel as master chip, electric energy computation chip, adopt CS5463, be provided with power excursion register, temperature register, First Harmonic Reactive Power register, temperature drift register, detection method is by repeatedly reading electric energy computation chip internal reference numerical value in the unit interval, mean value is obtained after summation, the reactive power of detection method to the harmonic wave in detected system compensates and comprises: 1) by calculating the harmonic wave reactive power obtaining detected system, 2) reactive-load compensation is carried out by shnt capacitor.
Specific implementation process is, the First Harmonic Reactive Power of system to be detected is designated as Q
b, single-chip microcomputer is by repeatedly reading electric energy computation chip internal reference numerical value in the unit interval, by to power excursion register, temperature register, First Harmonic Reactive Power register, the numerical value of temperature drift register reads the error of the chip of update the system, the A/D signal of method to three-phase electricity number of Laplace transform is used to analyze, make the measured value of system more accurate, electric current is obtained after summation, voltage, the mean value of active power, be designated as I respectively, U, P, then applied power S is calculated respectively, reactive power Q, wherein, S=IxU, by the known Q of power triangle shown in Fig. 2
2=S
2-P
2, draw reactive power Q numerical value after evolution, then calculate the harmonic wave reactive power Q of system to be detected
x, Q
x=Q-Q
b, obtain Q
xafter, utilize the principle of reactive-load compensation, compensated by shnt capacitor,
The selection of capacitor installed capacity, utilizes above-mentioned gained Q
x, according to the vector relations between power, can obtain reactive compensation capacity Qc, computing formula is as follows,
In formula, P---the average active power of the peak load moon, KW;
Tg φ 1, tg φ 2---the tangent value of power-factor angle before and after compensating;
Cos φ 1, cos φ 2---power factor value before and after compensating;
Can look-up table be utilized, find every 1KW active power, power factor, the required capacity compensated before and after improving, then be multiplied by the monthly average active power of peak load, required reactive compensation capacity can be calculated.
Claims (4)
1. a three phase electrical parameters detection method, adopt single-chip microcomputer, single-chip microcomputer is provided with voltage, current signal collector, electric energy computation chip, it is characterized in that, described detection method is when processing voltage, current signal, under the prerequisite that active power is constant, reactive power for the harmonic wave in detected system makes compensation, described detection method also adopts the A/D signal of Laplace transform to three phase electrical parameters to analyze, and in conjunction with time domain, the zero point of complex frequency domain two aspect, Poles Analysis, accurate Calculation and collection are carried out to voltage, current signal.
2. a kind of three phase electrical parameters detection method according to claim 1, it is characterized in that, described single-chip microcomputer adopts STM32F103VET6 chip based on Cortex-M3 kernel as master chip, and described electric energy computation chip is provided with power excursion register, temperature register, First Harmonic Reactive Power register, temperature drift register.
3. a kind of three phase electrical parameters detection method according to claim 1, it is characterized in that, the reactive power of described detection method to the harmonic wave in detected system compensates and comprises: 1) by calculating the harmonic wave reactive power obtaining detected system, 2) carry out reactive-load compensation by shnt capacitor.
4. a kind of three phase electrical parameters detection method according to claim 1, is characterized in that, described detection method, by repeatedly reading electric energy computation chip internal reference numerical value in the unit interval, obtains mean value after summation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410814383.6A CN104502686A (en) | 2014-12-22 | 2014-12-22 | Method for detecting three-phase electric parameter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410814383.6A CN104502686A (en) | 2014-12-22 | 2014-12-22 | Method for detecting three-phase electric parameter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104502686A true CN104502686A (en) | 2015-04-08 |
Family
ID=52944097
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410814383.6A Pending CN104502686A (en) | 2014-12-22 | 2014-12-22 | Method for detecting three-phase electric parameter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104502686A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111130414A (en) * | 2020-01-03 | 2020-05-08 | 沈机（上海）智能系统研发设计有限公司 | Motor average current smoothing method and system and motor current sampling equipment |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09215197A (en) * | 1996-01-31 | 1997-08-15 | Meidensha Corp | Active filter device |
| CN201860121U (en) * | 2010-11-25 | 2011-06-08 | 广东雅达电子股份有限公司 | Reactive compensator |
| CN203553956U (en) * | 2013-06-07 | 2014-04-16 | 湖南大学 | Rural 10kV electric power circuit reactive power compensation controller |
-
2014
- 2014-12-22 CN CN201410814383.6A patent/CN104502686A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09215197A (en) * | 1996-01-31 | 1997-08-15 | Meidensha Corp | Active filter device |
| CN201860121U (en) * | 2010-11-25 | 2011-06-08 | 广东雅达电子股份有限公司 | Reactive compensator |
| CN203553956U (en) * | 2013-06-07 | 2014-04-16 | 湖南大学 | Rural 10kV electric power circuit reactive power compensation controller |
Non-Patent Citations (2)
| Title |
|---|
| PQR112: "cs5463中文资料", 《百度文库》 * |
| 董志春: "基于CS5463的TSC型无功补偿控制器的研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111130414A (en) * | 2020-01-03 | 2020-05-08 | 沈机（上海）智能系统研发设计有限公司 | Motor average current smoothing method and system and motor current sampling equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109579880B (en) | Magnetic encoder with adaptive compensation function | |
| CN105738696B (en) | Full phase time shift phase difference frequency estimating methods and device | |
| CN102288807A (en) | Method for measuring electric network voltage flicker | |
| CN203133168U (en) | Power harmonic detector | |
| CN102565574A (en) | Ship electric energy quality monitoring system | |
| CN101806832A (en) | Measuring method for frequencies of low-frequency signals | |
| CN106066437B (en) | A kind of on-line monitoring device of metallic oxide arrester and its monitoring method | |
| CN104267258B (en) | A kind of harmonic wave instantaneous power computational methods utilizing incomplete S-transformation | |
| WO2017113754A1 (en) | Method for detecting dynamic reactive power of grid and reactive power detector | |
| CN203722628U (en) | Power carrier channel communication tester | |
| CN102890190A (en) | Multiwavelet-based random non-linear load active energy metering method | |
| CN103412209B (en) | A kind of off resonance degree detection method of tuned filter | |
| CN203551116U (en) | Device for collecting temperature of high-voltage overhead transmission line | |
| CN105628185B (en) | A kind of vibrating wire sensor frequency tripling screen method | |
| CN114016041A (en) | Oil-gas pipeline potential detection method and device for cathodic protection | |
| CN103513133B (en) | The measurement apparatus of MCR type SVC device dynamic response time and method | |
| CN102608423B (en) | Detection method of harmonic energy | |
| CN107870265A (en) | A kind of power-to-ground capacitance detection method based on high-precision DFT | |
| CN104502686A (en) | Method for detecting three-phase electric parameter | |
| CN204679550U (en) | Electric energy accurate measuring device under a kind of fluctuating load | |
| CN110007146A (en) | A kind of resonance point detecting method based on voltage and current harmonic phase | |
| CN103389423A (en) | Power quality analyzer | |
| CN202486308U (en) | Harmonic electric quantity measuring system | |
| CN203672975U (en) | Harmonic-impedance measuring device for power system | |
| CN104850751A (en) | Current quality assessment method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20150408 |
|
| RJ01 | Rejection of invention patent application after publication |