CN102890173A - Reactive power measurement method and device capable of improving reactive power error - Google Patents
Reactive power measurement method and device capable of improving reactive power error Download PDFInfo
- Publication number
- CN102890173A CN102890173A CN201210315438XA CN201210315438A CN102890173A CN 102890173 A CN102890173 A CN 102890173A CN 201210315438X A CN201210315438X A CN 201210315438XA CN 201210315438 A CN201210315438 A CN 201210315438A CN 102890173 A CN102890173 A CN 102890173A
- Authority
- CN
- China
- Prior art keywords
- reactive power
- diode
- power metering
- mains frequency
- metering method
- 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.)
- Granted
Links
Images
Abstract
The invention relates to a reactive power measurement method and device capable of improving a reactive power error. The method comprises the following steps: 1) inputting a voltage signal into an operation amplifier through a diode, and outputting a zero crossing signal; 2) connecting the output end of the operation amplifier with an interruption pin of a single chip micro-computer; 3) measuring a time interval between two interruption signals by a timer of the single chip micro-computer; 4) taking a reciprocal of the time interval acquired in step 3) so as to acquire a power frequency; and 5) outputting the power frequency to a measurement chip so as to measure the reactive power. According to the invention, the timer of the single chip micro-computer is used for measuring the power frequency to obtain the real-time power frequency, so that the frequency affected reactive power error can be improved. With the method, the power frequency can be timely updated during the reactive frequency affected switching, and the reactive power error is normal.
Description
Technical field
The present invention relates to the power network monitoring field, more particularly, relate to a kind of reactive power metering method and device that improves idle error.
Background technology
Chinese utility model patent ZL 200320123064.8 relates to a kind of wattless power measurement circuit of spending phase shifts for the realization 90 of full electronic watt-hour meter, comprising: the A/D conversion circuit of received current channel signal, down-sampled circuit, low-pass filter circuit; The A/D conversion circuit of receiver voltage channel signal, phase compensating circuit; Receive respectively digital multiplier, low-pass filter circuit, numeral/freq converting circuit through low-pass filter circuit and phase compensating circuit signal; Be characterized in: a differentiation element circuit that can carry out 90 ° of phase shifts is set between down-sampled circuit and low-pass filter circuit; This differentiation element circuit comprises: a clock circuit, a delayer and a subtracter, two input ends of this subtracter are connected with the delayer output terminal with signal input signal end respectively.Thereby realize 90 ° phase shift and the metering of reactive power; Its method precision simple and phase shift is high, and is insensitive to the grid central frequency skew, can guarantee the computational accuracy of reactive power, therefore very practical.
Although above-mentioned utility model patent has solved the problem of the computational accuracy of reactive power, goes back Shortcomings:
Computation chip CS5463 is as the A/D conversion chip of special use, its inner integrated electrical network frequency measurement unit, measuring accuracy is also very high, can reach 0.00001 second, be cured as for 10 seconds when but its frequency values renewal speed chip dispatches from the factory, and the reactive measurement function of computation chip CS5463 needs accurately real-time mains frequency normally to measure.
When doing the frequency influence test, need to measure the idle error amount of each Frequency point, mains frequency upgrades after switching to another Frequency point from a Frequency point, but the frequency period of computation chip internal measurement does not arrive, still use with the frequency before switching, at this moment the reactive power that records is just incorrect, reaction will occur beginning to have several large errors on idle error, and the error that records is underproof.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, provide a kind of single-chip microcomputer timer that utilizes to measure mains frequency, obtain real-time mains frequency, reactive power metering method and the device of the idle error when improving frequency influence.
Technical scheme of the present invention is as follows:
A kind of reactive power metering method of improving idle error, step is as follows:
1) voltage signal is exported zero cross signal through the diode input operational amplifier;
2) output terminal of operational amplifier is connected with the interrupt pin of single-chip microcomputer;
3) timer of single-chip microcomputer is measured the time interval between look-at-me and look-at-me;
4) time interval of step 3) is got inverse, obtain mains frequency;
5) the output mains frequency carries out the reactive power metering to computation chip.
As preferably, before the voltage signal of step 1) enters diode, carry out step-down through resistor network.
As preferably, described resistor network comprises an above resistance, RC parallel circuit; Described resistance is connected, and connects with diode; RC parallel circuit one end is connected between resistance in series and the diode, other end ground connection.
As preferably, the average mains frequency that the described mains frequency of step 4) is tried to achieve after cumulative for the mains frequency of at least one electrical network.
As preferably, the middle fracture of described single-chip microcomputer is no less than the number of electrical network to be measured.
As preferably, described voltage is ployphase voltages, and single-chip microcomputer is when measuring the mains frequency of ployphase voltages, by default each phase voltage of sequence detection, if current voltage surpasses the predeterminated voltage value, then measure the mains frequency of current phase voltage, otherwise judge next phase voltage.
As preferably, if each phase voltage all is lower than the predeterminated voltage value, then the accident mains frequency adopts the acquiescence mains frequency.
As preferably, the acquiescence mains frequency is 50Hz.
As preferably, the cycle of the timer of described single-chip microcomputer is 1 millisecond.
A kind of device of realizing improving the reactive power metering method of idle error comprises operational amplifier, diode, single-chip microcomputer, and described diode is connected with the input end forward of operational amplifier, and the output terminal of operational amplifier is connected with the interrupt pin of single-chip microcomputer.
As preferably, before diode, be connected with the dropping resistor network.
As preferably, described resistor network comprises an above resistance, RC parallel circuit; Described resistance is connected, and connects with diode; RC parallel circuit one end is connected between resistance in series and the diode, other end ground connection.
Beneficial effect of the present invention is as follows:
The present invention utilizes the single-chip microcomputer timer to measure mains frequency, obtains real-time mains frequency, the idle error when improving frequency influence.Mains frequency can upgrade in time when doing idle frequency influence switching after use the method, and idle error is normal.
Description of drawings
Fig. 1 is method flow schematic diagram of the present invention;
Fig. 2 is apparatus structure schematic diagram of the present invention;
Among the figure: R1 to R38 is resistance, and C1 to C8 is electric capacity, and D1 to D3 is diode, and U1, U2 are operational amplifier LM2902, and U3 is single-chip microcomputer, and A, B, C are A phase, B phase, the C phases of three-phase voltage.
Embodiment
Below in conjunction with drawings and Examples the present invention is further described in detail.
A kind of reactive power metering method of improving idle error of the present invention, step is as follows:
1) voltage signal is exported zero cross signal through the diode input operational amplifier;
2) output terminal of operational amplifier is connected with the interrupt pin of single-chip microcomputer;
3) timer of single-chip microcomputer is measured the time interval between look-at-me and look-at-me;
4) time interval of step 3) is got inverse, obtain mains frequency;
5) the output mains frequency carries out the reactive power metering to computation chip.
The present invention also provides a kind of device of realizing improving the reactive power metering method of idle error, comprise operational amplifier, diode, single-chip microcomputer, described diode is connected with the input end forward of operational amplifier, and the output terminal of operational amplifier is connected with the interrupt pin of single-chip microcomputer.Before diode, be connected with the dropping resistor network.Described resistor network comprises an above resistance, RC parallel circuit; Described resistance is connected, and connects with diode; RC parallel circuit one end is connected between resistance in series and the diode, other end ground connection.
Embodiment
In the present embodiment, the realization of method of the present invention, required hardware resource is that 3 middle fractures, 1 cycle are 1 millisecond of timer, measures the mains frequency of three-phase.When the A phase voltage is surveyed A phase frequency during greater than 135V, if otherwise the B phase voltage is surveyed B phase frequency during greater than 135V, if otherwise the C phase voltage is surveyed C phase frequency during greater than 135V, if three-phase voltage all is lower than then measured frequency not of 135V, the acquiescence mains frequency is 50Hz.The mains frequency of ammeter three-phase input is consistent generally speaking, surveys one and gets final product mutually.Be that the frequency that 60% low voltage of 220V is measured may be not too accurate when voltage is lower than 135V, then attempt the voltage of other phases of test.
In the present embodiment, operational amplifier is LM2902, and namely peripheral circuit is comprised of diode and integrated circuit LM2902.
As shown in Figure 1, a kind of reactive power metering method of improving idle error, step is as follows:
S1, three-phase voltage signal input;
S2, voltage signal are input to the LM2902 input end by diode after the resistor network step-down;
S3, through diode and LM2902 output crossover point signal; Its output terminal of zero crossing of the every mistake of voltage all can produce a level to be changed;
The output terminal of S4, LM2902 is received the interrupt pin of single-chip microcomputer, and voltage each time zero crossing single-chip microcomputer all can interrupt;
The timer of S5, handy single-chip microcomputer is measured the time interval between look-at-me and the look-at-me;
S6, in order to obtain stable mains frequency, a plurality of mains frequencies are added up to be averaging again; In the present embodiment, accumulate 50 and interrupt the required time, be averaging 50 and interrupt the required time;
S7, this time is got inverse obtain mains frequency; The frequency accuracy that obtains can reach 0.001 second, i.e. 1KHz, and the update cycle is can meet the requirements in 1 second;
S8, output mains frequency carry out the reactive power metering to computation chip.
As shown in Figure 2, in the present embodiment, comprise two LM2902, be used for measuring the mains frequency of three-phase after being connected with single-chip microcomputer.Wherein a slice LM2902 measures the A phase, and another sheet LM2902 measures B phase, C phase.The output terminal of LM2902 is connected with the interrupt pin of single-chip microcomputer respectively.The input end of LM2902 is connected with diode forward respectively, connects respectively the dropping resistor network at diode.
Described resistor network comprises a plurality of resistance, RC parallel circuit; The series connection of described resistance, and an end connects with diode, and the other end links to each other with the input of each phase voltage respectively.RC parallel circuit one end is connected between resistance in series and the diode, other end ground connection.
Above-described embodiment only is that the present invention is described, and is not as limitation of the invention.So long as according to technical spirit of the present invention, to above-described embodiment change, modification etc. all will drop in the scope of claim of the present invention.
Claims (12)
1. a reactive power metering method of improving idle error is characterized in that, step is as follows:
1) voltage signal is exported zero cross signal through the diode input operational amplifier;
2) output terminal of operational amplifier is connected with the interrupt pin of single-chip microcomputer;
3) timer of single-chip microcomputer is measured the time interval between look-at-me and look-at-me;
4) time interval of step 3) is got inverse, obtain mains frequency;
5) the output mains frequency carries out the reactive power metering to computation chip.
2. the reactive power metering method of the idle error of improvement according to claim 1 is characterized in that, before the voltage signal of step 1) enters diode, carries out step-down through resistor network.
3. the reactive power metering method of the idle error of improvement according to claim 2 is characterized in that, described resistor network comprises an above resistance, RC parallel circuit; Described resistance is connected, and connects with diode; RC parallel circuit one end is connected between resistance in series and the diode, other end ground connection.
4. the reactive power metering method of the idle error of improvement according to claim 1 is characterized in that, the described mains frequency of step 4) is the average mains frequency of trying to achieve after the mains frequency of at least one electrical network adds up.
5. the reactive power metering method of the idle error of improvement according to claim 4 is characterized in that, the middle fracture of described single-chip microcomputer is no less than the number of electrical network to be measured.
6. the reactive power metering method of the idle error of improvement according to claim 1, it is characterized in that, described voltage is ployphase voltages, single-chip microcomputer is when measuring the mains frequency of ployphase voltages, by default each phase voltage of sequence detection, if current voltage surpasses the predeterminated voltage value, then measure the mains frequency of current phase voltage, otherwise judge next phase voltage.
7. the reactive power metering method of the idle error of improvement according to claim 6 is characterized in that, if each phase voltage all is lower than the predeterminated voltage value, then the accident mains frequency adopts the acquiescence mains frequency.
8. the reactive power metering method of the idle error of improvement according to claim 6 is characterized in that, the acquiescence mains frequency is 50Hz.
9. the reactive power metering method of the idle error of improvement according to claim 1 is characterized in that, the cycle of the timer of described single-chip microcomputer is 1 millisecond.
10. device of realizing improving the reactive power metering method of idle error, it is characterized in that, comprise operational amplifier, diode, single-chip microcomputer, described diode is connected with the input end forward of operational amplifier, and the output terminal of operational amplifier is connected with the interrupt pin of single-chip microcomputer.
11. realization according to claim 10 improves the device of the reactive power metering method of idle error, it is characterized in that, is connected with the dropping resistor network before diode.
12. realization according to claim 10 improves the device of the reactive power metering method of idle error, it is characterized in that, described resistor network comprises an above resistance, RC parallel circuit; Described resistance is connected, and connects with diode; RC parallel circuit one end is connected between resistance in series and the diode, other end ground connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210315438.XA CN102890173B (en) | 2012-08-30 | 2012-08-30 | A kind of reactive power metering method and device improving reactive power error |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210315438.XA CN102890173B (en) | 2012-08-30 | 2012-08-30 | A kind of reactive power metering method and device improving reactive power error |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102890173A true CN102890173A (en) | 2013-01-23 |
| CN102890173B CN102890173B (en) | 2016-02-24 |
Family
ID=47533738
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210315438.XA Active CN102890173B (en) | 2012-08-30 | 2012-08-30 | A kind of reactive power metering method and device improving reactive power error |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102890173B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104869587A (en) * | 2015-05-29 | 2015-08-26 | 上海大学 | Time synchronization error measurement method for wireless sensor network |
| WO2017092518A1 (en) * | 2015-11-30 | 2017-06-08 | 珠海格力电器股份有限公司 | Method and device for controlling photovoltaic air conditioning system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2703260Y (en) * | 2003-12-31 | 2005-06-01 | 上海贝岭股份有限公司 | Wattless power measuring circuit for realizing 90 degree phase shifting |
| CN2836306Y (en) * | 2005-06-14 | 2006-11-08 | 顾祝君 | Reactive power tracking compensator |
| CN101995514A (en) * | 2009-08-27 | 2011-03-30 | 北京兴中芯电子科技有限公司 | Device and method for measuring reactiv power |
| CN102012456A (en) * | 2010-10-29 | 2011-04-13 | 东南大学 | Reactive power measurement method |
| CN102035554A (en) * | 2010-11-19 | 2011-04-27 | 钜泉光电科技(上海)股份有限公司 | System and method for metering and analyzing electric energy as well as analog-to-digital conversion circuit |
-
2012
- 2012-08-30 CN CN201210315438.XA patent/CN102890173B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2703260Y (en) * | 2003-12-31 | 2005-06-01 | 上海贝岭股份有限公司 | Wattless power measuring circuit for realizing 90 degree phase shifting |
| CN2836306Y (en) * | 2005-06-14 | 2006-11-08 | 顾祝君 | Reactive power tracking compensator |
| CN101995514A (en) * | 2009-08-27 | 2011-03-30 | 北京兴中芯电子科技有限公司 | Device and method for measuring reactiv power |
| CN102012456A (en) * | 2010-10-29 | 2011-04-13 | 东南大学 | Reactive power measurement method |
| CN102035554A (en) * | 2010-11-19 | 2011-04-27 | 钜泉光电科技(上海)股份有限公司 | System and method for metering and analyzing electric energy as well as analog-to-digital conversion circuit |
Non-Patent Citations (1)
| Title |
|---|
| 刘骏跃: "电网功率因数的测量及无功自动补偿控制", 《煤矿机械》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104869587A (en) * | 2015-05-29 | 2015-08-26 | 上海大学 | Time synchronization error measurement method for wireless sensor network |
| CN104869587B (en) * | 2015-05-29 | 2018-10-23 | 上海大学 | Time Synchronization for Wireless Sensor Networks error assay method |
| WO2017092518A1 (en) * | 2015-11-30 | 2017-06-08 | 珠海格力电器股份有限公司 | Method and device for controlling photovoltaic air conditioning system |
| EP3385631A4 (en) * | 2015-11-30 | 2019-08-07 | Gree Electric Appliances, Inc. of Zhuhai | Method and device for controlling photovoltaic air conditioning system |
| US11015821B2 (en) | 2015-11-30 | 2021-05-25 | Gree Electric Appliances, Inc. Of Zhuhai | Method and device for controlling photovoltaic air conditioning system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102890173B (en) | 2016-02-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101788615B (en) | Simple method for detecting phase sequence of three-phase industrial-frequency alternating current and detection device | |
| CN102628892B (en) | Method for calculating voltage-loss unusual electrical energy measurement on line and electric energy meter | |
| CN104267373A (en) | Gateway meter assessment device | |
| CN103257271A (en) | Device and method for detecting micro grid harmonic wave and inter-harmonics based on STM32F107VCT6 | |
| CN201993462U (en) | Three-phase intelligent electric energy meter checking device | |
| CN103901388A (en) | Parallel detection terminal device and detection method | |
| CN104076321A (en) | On-line monitoring and evaluating system and method for digital electric energy meter | |
| CN104569902A (en) | Digital type electric energy meter power consumption measuring device and method | |
| CN104062617B (en) | Combining unit meter characteristic filed detection system and method thereof | |
| CN107105056A (en) | A kind of cloud control electric meter system based on WiFi communication | |
| CN106405482B (en) | Nonlinear load metering precision measuring device of digital electric energy meter | |
| CN103645457A (en) | On-site inspection device for electric energy meter | |
| CN102944741B (en) | Abnormal power usage monitoring method based on local power reference | |
| CN100425995C (en) | Circuit and method for preventing shunt running in electric energy measurement | |
| CN101458275A (en) | High temperature resistant three phase intermediate frequency electric quantity acquisition module | |
| CN100425994C (en) | Circuit and method for preventing shunt running in electric energy measurement | |
| CN204758693U (en) | A electrical measurement device for building intelligent electric system of using | |
| CN102890173B (en) | A kind of reactive power metering method and device improving reactive power error | |
| CN108535575A (en) | Power quality analysis device based on short-distance wireless communication technology | |
| CN102645581B (en) | Low-tension electricity metering device | |
| CN204028338U (en) | A kind of merge cells meter characteristic field detecting device | |
| CN212060551U (en) | Single-phase electric energy meter on-site inspection instrument | |
| CN107121659A (en) | A kind of three-phase electric energy meter on-site detection means and detection method | |
| CN203673058U (en) | Electric energy meter field inspecting apparatus | |
| CN203909139U (en) | Metering chip based on one-cycle control technology |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CB03 | Change of inventor or designer information |
Inventor after: Chen Baosheng Inventor after: Zeng Gege Inventor after: Xu Laishun Inventor after: Xu Huifeng Inventor before: Chen Baosheng Inventor before: Zeng Gege Inventor before: Xu Laishun Inventor before: Xu Huifeng |
|
| COR | Change of bibliographic data |