CN113884726A - Three-phase smart electric meter with quick calibration structure - Google Patents
Three-phase smart electric meter with quick calibration structure Download PDFInfo
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- CN113884726A CN113884726A CN202111213048.7A CN202111213048A CN113884726A CN 113884726 A CN113884726 A CN 113884726A CN 202111213048 A CN202111213048 A CN 202111213048A CN 113884726 A CN113884726 A CN 113884726A
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- 238000009966 trimming Methods 0.000 claims abstract description 54
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- 238000013523 data management Methods 0.000 claims description 12
- 238000012544 monitoring process Methods 0.000 claims description 7
- 238000012423 maintenance Methods 0.000 claims description 5
- 230000008569 process Effects 0.000 abstract description 11
- 238000005259 measurement Methods 0.000 abstract description 7
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- 238000001514 detection method Methods 0.000 abstract description 5
- 238000005457 optimization Methods 0.000 description 7
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R11/00—Electromechanical arrangements for measuring time integral of electric power or current, e.g. of consumption
- G01R11/02—Constructional details
- G01R11/04—Housings; Supporting racks; Arrangements of terminals
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R22/00—Arrangements for measuring time integral of electric power or current, e.g. electricity meters
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Abstract
The invention discloses a three-phase intelligent ammeter with a quick calibration structure, which comprises a three-phase intelligent ammeter, wherein the three-phase intelligent ammeter comprises a terminal processor, the input end of the terminal processor is electrically connected with a voltage measurement end and a current measurement end respectively, the output end of the terminal processor is electrically connected with a display module in a bidirectional mode, the output end of the terminal processor is electrically connected with a voltage and current calibration channel and a data cache module in a bidirectional mode, and the output end of the voltage and current calibration channel is electrically connected with a split-phase trimming module in a bidirectional mode. According to the invention, in the operation process of the three-phase intelligent ammeter, the current voltage channel and the range current are added for detection, and the split-phase trimming module is used for synchronously trimming a plurality of split phases, so that the effect of trimming the combined phase precision is achieved after the split phases are trimmed, and the problems that the conventional three-phase intelligent ammeter is slow in calibration efficiency, has deviation of output stable time in the operation process and is easy to influence the calibration accuracy are solved.
Description
Technical Field
The invention relates to the technical field of electric power, in particular to a three-phase intelligent electric meter with a quick calibration structure.
Background
The ammeter is the short for electric energy meter, is used for measuring the instrument of electric energy quantity, mainly produces the shift-in magnetic field through voltage, the current element synthesis, makes the disc rotate under its effect, and the disc rotational speed is directly proportional can load the size of electric current, reaches the purpose of measurement electric energy, but current three-phase smart electric meter calibration efficiency is slower, can appear exporting the deviation of stabilization time in the operation process, and calibration accuracy receives the influence easily moreover.
Disclosure of Invention
In order to solve the problems in the background art, the invention aims to provide a three-phase intelligent electric meter with a quick calibration structure, which has the advantage of improving the calibration efficiency and solves the problems that the conventional three-phase intelligent electric meter is slow in calibration efficiency, the deviation of output stable time occurs in the operation process, and the calibration accuracy is easily influenced.
In order to achieve the purpose, the invention provides the following technical scheme: a three-phase intelligent ammeter with a quick calibration structure comprises a three-phase intelligent ammeter;
the three-phase intelligent ammeter comprises a terminal processor, wherein the input end of the terminal processor is respectively and electrically connected with a voltage measuring end and a current measuring end, the output end of the terminal processor is electrically connected with a display module in two directions, the output end of the terminal processor is respectively electrically connected with a voltage and current calibration channel and a data cache module in two directions, the output end of the voltage and current calibration channel is bidirectionally and electrically connected with a split-phase trimming module, the output end of the split-phase trimming module is bidirectionally and electrically connected with the input end of the terminal processor, the output end of the terminal processor is electrically connected with a comparison unit in a bidirectional way, the input end of the comparison unit is electrically connected with the output end of the data management module in a bidirectional way, the two-way electricity of comparison unit's output is connected with data transceiver module, the long-range two-way electricity of data transceiver module's output is connected with high in the clouds monitoring module.
Preferably, the voltage and current calibration channel is composed of a dc offset unit, an ac gain unit and an ac offset unit.
Preferably, the split-phase trimming module is composed of a power soft trimming unit, a phase soft trimming unit and a reactive soft trimming unit.
Preferably, an electromagnetic shielding cover is installed inside the three-phase smart electric meter, and the voltage and current calibration channel and the split-phase trimming module are both located inside the electromagnetic shielding cover.
Preferably, the data management module comprises a file sorting unit and a history recording unit.
Preferably, the data cache module is installed inside the three-phase smart electric meter, and the data management module and the comparison unit are both electrically connected inside the data cache module in a bidirectional manner.
Preferably, the output end of the terminal processor is bidirectionally and electrically connected with a system setting module, the input end of the system setting module is bidirectionally and electrically connected with the output end of the data transceiving module, and the input end of the cloud monitoring module is bidirectionally and electrically connected with the mobile terminal.
Preferably, the system setting module comprises a time setting unit, a screen calibration unit and a maintenance debugging unit.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the invention, in the operation process of the three-phase intelligent ammeter, the current voltage channel and the range current are added for detection, and the split-phase trimming module is used for synchronously trimming a plurality of split phases, so that the effect of trimming the combined phase precision is achieved after the split phases are trimmed, and the problems that the conventional three-phase intelligent ammeter is slow in calibration efficiency, has deviation of output stable time in the operation process and is easy to influence the calibration accuracy are solved.
2. According to the invention, the voltage and current calibration channel is formed by the direct current offset unit, the alternating current gain unit and the alternating current offset unit, so that the measuring range current can be applied to different current signals according to requirements, and the current and voltage calibration range and accuracy are greatly improved.
3. According to the invention, the power soft trimming unit, the phase soft trimming unit and the reactive soft trimming unit form the split-phase trimming module, so that the phase-combining data can be unpacked into a plurality of split phases for measurement, the trimming pressure of the split-phase trimming module is reduced, and the calibration efficiency is improved.
4. According to the invention, the electromagnetic shielding cover is arranged, so that the voltage and current calibration channel and the split-phase trimming module can be protected, and the influence of electric radiation inside the three-phase intelligent electric meter on the three-phase intelligent electric meter is reduced.
5. The invention forms a data management module by setting a file sorting unit and a history recording unit, and can be used for inquiring historical data, saving temporary data, deleting useless data or sorting memory space.
6. By arranging the data caching module, the invention can reduce the operating pressure of the terminal processor, can buffer the data and improve the data extraction speed.
7. According to the invention, by arranging the system setting module and the mobile terminal, a user can conveniently and remotely debug the three-phase intelligent electric meter, and the operation difficulty of the three-phase intelligent electric meter is reduced.
8. According to the invention, the time setting unit, the screen calibration unit and the maintenance debugging unit form a system setting module, so that the automatic calibration interval time can be set, and the influence of power utilization errors on data recording is further eliminated.
Drawings
FIG. 1 is a schematic diagram of the system of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in fig. 1, the three-phase smart meter with the rapid calibration structure provided by the invention comprises a three-phase smart meter;
three-phase smart electric meter includes the terminal treater, the input difference electric connection of terminal treater has voltage measurement end and current measurement end, the two-way electricity of output of terminal treater is connected with display module, the output difference two-way electricity of terminal treater is connected with voltage current calibration passageway and data cache module, the two-way electricity of output of voltage current calibration passageway is connected with the phase splitting trimming module, the output of phase splitting trimming module is connected with the two-way electricity of input of terminal treater, the two-way electricity of output of terminal treater is connected with the contrast unit, the input of contrast unit is connected with the two-way electricity of output of data management module, the two-way electricity of output of contrast unit is connected with data transceiver module, the long-range two-way electricity of output of data transceiver module is connected with high in the clouds monitoring module.
Referring to fig. 1, the voltage-current calibration channel is composed of a dc offset unit, an ac gain unit, and an ac offset unit.
As a technical optimization scheme of the invention, the voltage and current calibration channel is formed by the direct current offset unit, the alternating current gain unit and the alternating current offset unit, so that the range current can be applied to different current signals according to requirements, and the current and voltage calibration range and accuracy are greatly improved.
Referring to fig. 1, the split-phase trimming module is composed of a power soft trimming unit, a phase soft trimming unit, and a reactive soft trimming unit.
As a technical optimization scheme, the split-phase trimming module is composed of the power soft trimming unit, the phase soft trimming unit and the reactive soft trimming unit, the phase-combination data can be unpacked into a plurality of split phases for measurement, the trimming pressure of the split-phase trimming module is reduced, and the calibration efficiency is improved.
Referring to fig. 1, an electromagnetic shielding cover is installed inside the three-phase smart electric meter, and the voltage and current calibration channel and the split-phase trimming module are both located inside the electromagnetic shielding cover.
As a technical optimization scheme of the invention, the voltage and current calibration channel and the split-phase trimming module can be protected by arranging the electromagnetic shielding cover, and the influence of the internal electric radiation of the three-phase intelligent electric meter on the voltage and current calibration channel and the split-phase trimming module is reduced.
Referring to fig. 1, the data management module includes a file sorting unit and a history recording unit.
As a technical optimization scheme of the invention, a data management module is formed by setting a file sorting unit and a history recording unit and can be used for inquiring historical data, saving temporary data, deleting useless data or sorting memory space.
Referring to fig. 1, a data caching module is installed inside the three-phase smart electric meter, and the data management module and the comparison unit are both electrically connected inside the data caching module in a bidirectional manner.
As a technical optimization scheme of the invention, by arranging the data cache module, the operating pressure of the terminal processor can be reduced, data can be buffered, and the data extraction speed is increased.
Referring to fig. 1, the output end of the terminal processor is electrically connected with a system setting module in a bidirectional manner, the input end of the system setting module is electrically connected with the output end of the data transceiver module in a bidirectional manner, and the input end of the cloud monitoring module is electrically connected with a mobile terminal in a bidirectional manner.
As a technical optimization scheme, the system setting module and the mobile terminal are arranged, so that a user can conveniently and remotely debug the three-phase intelligent electric meter, and the operation difficulty of the three-phase intelligent electric meter is reduced.
Referring to fig. 1, the system setup module includes a time setup unit, a screen calibration unit, and a maintenance debugging unit.
As a technical optimization scheme of the invention, the time setting unit, the screen calibration unit and the maintenance debugging unit form a system setting module, so that the automatic calibration interval time can be set, and the influence of power utilization errors on data recording is further eliminated.
The working principle and the using process of the invention are as follows: when the three-phase intelligent electric meter is used, the user electricity consumption is detected through the voltage measuring end and the current measuring end and is displayed on the surface of the display module through the calculation of the terminal processor, meanwhile, the terminal processor stores detection data in the data management module, the comparison unit regularly carries out data interaction with the cloud monitoring module through the data transceiver module and extracts the real-time electricity consumption of the user in the operation process of the three-phase intelligent electric meter, when the detection data of the three-phase intelligent electric meter and the cloud data have errors, the current and voltage channel is added with the range current for detection, then three points of the power soft trimming unit, the phase soft trimming unit and the reactive soft trimming unit are respectively debugged, A, B, C phase splitting is used for trimming, after the phase splitting trimming is finished, the effect of trimming the phase precision is achieved, when the phase splitting trimming is carried out, the other two phases can be added with voltage but can not be added with current, namely, the other two phases are ensured not to generate power, the corrected data are transmitted to the terminal processor again and compared with the cloud data for the second time, and the original data are replaced after confirmation, so that the effect of quick calibration is achieved.
In summary, the following steps: this take three-phase smart electric meter of quick calibration structure, through in three-phase smart electric meter operation process, the current-voltage passageway detects in addition the range current, split-phase trimming module carries out synchronous trimming to a plurality of split phases simultaneously, after the split-phase trimming finishes, reach the effect of trimming to the close looks precision of combination, it is slower to have solved current three-phase smart electric meter calibration efficiency, can appear exporting the deviation of stabilization time at the operation in-process, and the calibration degree of accuracy receives the problem of influence easily moreover.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (8)
1. A three-phase intelligent ammeter with a quick calibration structure comprises a three-phase intelligent ammeter;
the method is characterized in that: the three-phase intelligent ammeter comprises a terminal processor, wherein the input end of the terminal processor is respectively and electrically connected with a voltage measuring end and a current measuring end, the output end of the terminal processor is electrically connected with a display module in two directions, the output end of the terminal processor is respectively electrically connected with a voltage and current calibration channel and a data cache module in two directions, the output end of the voltage and current calibration channel is bidirectionally and electrically connected with a split-phase trimming module, the output end of the split-phase trimming module is bidirectionally and electrically connected with the input end of the terminal processor, the output end of the terminal processor is electrically connected with a comparison unit in a bidirectional way, the input end of the comparison unit is electrically connected with the output end of the data management module in a bidirectional way, the two-way electricity of comparison unit's output is connected with data transceiver module, the long-range two-way electricity of data transceiver module's output is connected with high in the clouds monitoring module.
2. The three-phase smart meter with the rapid calibration structure of claim 1, wherein: the voltage and current calibration channel is composed of a direct current offset unit, an alternating current gain unit and an alternating current offset unit.
3. The three-phase smart meter with the rapid calibration structure of claim 1, wherein: the split-phase trimming module consists of a power soft trimming unit, a phase soft trimming unit and a reactive soft trimming unit.
4. The three-phase smart meter with the rapid calibration structure of claim 1, wherein: the three-phase smart electric meter is characterized in that an electromagnetic shielding cover is arranged inside the three-phase smart electric meter, and the voltage and current calibration channel and the split-phase trimming module are both located inside the electromagnetic shielding cover.
5. The three-phase smart meter with the rapid calibration structure of claim 1, wherein: the data management module comprises a file sorting unit and a history recording unit.
6. The three-phase smart meter with the rapid calibration structure of claim 1, wherein: the three-phase smart electric meter is characterized in that a data caching module is arranged inside the three-phase smart electric meter, and the data management module and the comparison unit are both electrically connected inside the data caching module in a bidirectional mode.
7. The three-phase smart meter with the rapid calibration structure of claim 1, wherein: the system is characterized in that a system setting module is electrically connected to the output end of the terminal processor in a bidirectional mode, the input end of the system setting module is electrically connected to the output end of the data receiving and transmitting module in a bidirectional mode, and the input end of the cloud monitoring module is electrically connected to the mobile terminal in a bidirectional mode.
8. The three-phase smart meter with the rapid calibration structure of claim 7, wherein: the system setting module comprises a time setting unit, a screen calibration unit and a maintenance debugging unit.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111213048.7A CN113884726A (en) | 2021-10-19 | 2021-10-19 | Three-phase smart electric meter with quick calibration structure |
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| CN202111213048.7A CN113884726A (en) | 2021-10-19 | 2021-10-19 | Three-phase smart electric meter with quick calibration structure |
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201796138U (en) * | 2010-06-09 | 2011-04-13 | 合肥工业大学 | Terminal calibration system based on electric energy measuring chip |
| CN203337709U (en) * | 2013-07-10 | 2013-12-11 | 兰州海红技术股份有限公司 | Intelligent electric instrument |
| CN105425197A (en) * | 2015-11-10 | 2016-03-23 | 深圳市科陆电子科技股份有限公司 | DC energy meter calibration method and system |
| CN107907850A (en) * | 2017-11-02 | 2018-04-13 | 华立科技股份有限公司 | Three-phase electric energy meter clock alignment and error calibrating method |
| CN109683122A (en) * | 2019-03-08 | 2019-04-26 | 广东电网有限责任公司 | A kind of three-phase normal power electric energy meter with self calibration diagnostic function |
| CN110673080A (en) * | 2019-09-27 | 2020-01-10 | 乐清市昊达电器有限公司 | Visual intelligent controller |
| CN111638481A (en) * | 2020-06-12 | 2020-09-08 | 浙江瑞银电子有限公司 | Large-current direct current ammeter and calibration method thereof |
| CN112946560A (en) * | 2021-02-03 | 2021-06-11 | 珠海格力电器股份有限公司 | Electric energy meter calibration method and device, electric energy meter and electric energy meter system |
| CN112946563A (en) * | 2021-03-16 | 2021-06-11 | 合肥艾通自动化工程有限公司 | Rapid calibration method for three-phase intelligent electric meter and three-phase intelligent electric meter |
| CN113064114A (en) * | 2020-03-30 | 2021-07-02 | 深圳友讯达科技股份有限公司 | High-precision quick meter calibration method for multi-core electric energy meter |
| CN113176531A (en) * | 2021-05-24 | 2021-07-27 | 苏州大学 | Passive calibration method of intelligent electric meter |
-
2021
- 2021-10-19 CN CN202111213048.7A patent/CN113884726A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201796138U (en) * | 2010-06-09 | 2011-04-13 | 合肥工业大学 | Terminal calibration system based on electric energy measuring chip |
| CN203337709U (en) * | 2013-07-10 | 2013-12-11 | 兰州海红技术股份有限公司 | Intelligent electric instrument |
| CN105425197A (en) * | 2015-11-10 | 2016-03-23 | 深圳市科陆电子科技股份有限公司 | DC energy meter calibration method and system |
| CN107907850A (en) * | 2017-11-02 | 2018-04-13 | 华立科技股份有限公司 | Three-phase electric energy meter clock alignment and error calibrating method |
| CN109683122A (en) * | 2019-03-08 | 2019-04-26 | 广东电网有限责任公司 | A kind of three-phase normal power electric energy meter with self calibration diagnostic function |
| CN110673080A (en) * | 2019-09-27 | 2020-01-10 | 乐清市昊达电器有限公司 | Visual intelligent controller |
| CN113064114A (en) * | 2020-03-30 | 2021-07-02 | 深圳友讯达科技股份有限公司 | High-precision quick meter calibration method for multi-core electric energy meter |
| CN111638481A (en) * | 2020-06-12 | 2020-09-08 | 浙江瑞银电子有限公司 | Large-current direct current ammeter and calibration method thereof |
| CN112946560A (en) * | 2021-02-03 | 2021-06-11 | 珠海格力电器股份有限公司 | Electric energy meter calibration method and device, electric energy meter and electric energy meter system |
| CN112946563A (en) * | 2021-03-16 | 2021-06-11 | 合肥艾通自动化工程有限公司 | Rapid calibration method for three-phase intelligent electric meter and three-phase intelligent electric meter |
| CN113176531A (en) * | 2021-05-24 | 2021-07-27 | 苏州大学 | Passive calibration method of intelligent electric meter |
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