CN110794207A - Three-phase manganin sampling alternating current guide rail meter - Google Patents

Three-phase manganin sampling alternating current guide rail meter Download PDF

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Publication number
CN110794207A
CN110794207A CN201911112760.0A CN201911112760A CN110794207A CN 110794207 A CN110794207 A CN 110794207A CN 201911112760 A CN201911112760 A CN 201911112760A CN 110794207 A CN110794207 A CN 110794207A
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CN
China
Prior art keywords
guide rail
circuit
sampling
current
rail meter
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Pending
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CN201911112760.0A
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Chinese (zh)
Inventor
诸葛先林
刘群华
肖春峰
项超
曾刚
陈玉江
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Zhejiang Risesun Science and Technology Co Ltd
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Zhejiang Risesun Science and Technology Co Ltd
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Priority to CN201911112760.0A priority Critical patent/CN110794207A/en
Publication of CN110794207A publication Critical patent/CN110794207A/en
Pending legal-status Critical Current

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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R22/00Arrangements for measuring time integral of electric power or current, e.g. electricity meters
    • G01R22/06Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
    • G01R22/061Details of electronic electricity meters
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R11/00Electromechanical arrangements for measuring time integral of electric power or current, e.g. of consumption
    • G01R11/02Constructional details
    • G01R11/04Housings; Supporting racks; Arrangements of terminals
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R22/00Arrangements for measuring time integral of electric power or current, e.g. electricity meters
    • G01R22/06Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
    • G01R22/061Details of electronic electricity meters
    • G01R22/063Details of electronic electricity meters related to remote communication
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R22/00Arrangements for measuring time integral of electric power or current, e.g. electricity meters
    • G01R22/06Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
    • G01R22/061Details of electronic electricity meters
    • G01R22/065Details of electronic electricity meters related to mechanical aspects
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R22/00Arrangements for measuring time integral of electric power or current, e.g. electricity meters
    • G01R22/06Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
    • G01R22/10Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods using digital techniques

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Measurement Of Current Or Voltage (AREA)

Abstract

A three-phase manganin sampling alternating current guide rail meter comprises a guide rail meter shell and a circuit module, wherein the circuit module comprises a measuring unit, a management control unit, a communication circuit and a power circuit, the management control unit comprises a processor, an LCD drive, a real-time clock, a display, a data memory and a light emitting diode, the measuring unit comprises three current sampling modules, three resistance voltage division sampling modules and a metering processing module, the current sampling modules comprise manganin resistors, a sampling signal modulation chip and an isolation pulse transformer, the current sampling modules connected into the ammeter complete coupling and are processed and converted into current digital signals through an integrated metering circuit, voltage is sampled and processed and converted into voltage digital signals through the integrated metering circuit, and a microprocessor collects the processed digital signals to perform data calculation and analysis processing, accurate real-time data is obtained. The design has the advantages of small and exquisite structure, accurate metering and low material cost.

Description

Three-phase manganin sampling alternating current guide rail meter
Technical Field
The invention relates to a three-phase manganin sampling alternating current guide rail meter, in particular to a three-phase manganin sampling alternating current guide rail meter with low cost and small volume.
Background
With the development of Chinese economy, the demand for electric energy is continuously increased, the three-phase electric meters are popularized and applied in the whole country, the demand for the three-phase electric meters is continuously increased in various industries, and particularly, the new energy industry, such as a plurality of large-scale charging devices, is greatly developed by the nation. Current sampling of the existing three-phase electronic electric energy meter on the market is realized by mutual inductor isolation sampling, voltage sampling is realized by resistance voltage division sampling, wherein the mutual inductor in the current sampling has overhigh relative cost and large volume, so that the whole electric energy meter has high price and large volume and is difficult to use and install. The single-phase electric energy meter realizes current sampling through manganin sampling current signals, voltage sampling is realized through resistance voltage division sampling voltage signals, generally speaking, the scheme of current manganin sampling is more applied to the single-phase electric energy meter, and in the three-phase electric energy meter, line voltage potential 380V between the three phases, in the practical application process even exceeds 380V, the scheme of directly adopting the manganin sampling can lead to serious short circuit between the three phases, and because the problem that whole three-phase electric energy meter is bulky, to some inconvenient installations of using, in addition, the current transformer sampling scheme who chooses for use has direct current and easily saturates, easily receive invariable magnetic field interference, the measuring error grow and then measure and miss scheduling problem.
Disclosure of Invention
The invention aims to provide a three-phase manganin sampling alternating current guide rail meter which is small in structure, accurate in metering and low in material cost.
In order to solve the technical problems, the invention adopts the following technical scheme: a three-phase manganin sampling alternating current guide rail meter comprises a guide rail meter shell and a circuit module arranged in the guide rail meter shell, wherein the circuit module comprises a measuring unit, a management control unit, a communication circuit, a power circuit and a functional circuit, and the measuring unit, the communication circuit, the power circuit and the functional circuit are respectively and electrically connected with the management control unit;
the management control unit comprises a processor, an LCD driver, a real-time clock, a display, a data memory and a light emitting diode, the measuring unit comprises three current sampling modules for the guide rail meter to acquire three-phase current, three resistance voltage division sampling circuits for the guide rail meter to acquire three-phase voltage and an integrated metering circuit working with the processor in a matching way, the current sampling modules comprise a manganin resistor, a sampling signal modulation chip and an isolation pulse transformer, the current connected to the ammeter is subjected to high-speed sampling through the manganin resistor, then is subjected to coupling after sequentially passing through the sampling signal modulation chip and the isolation pulse transformer, is processed and converted into a current digital signal through the integrated metering circuit, the voltage is subjected to sampling through the resistance voltage division sampling circuits and then is processed and converted into a voltage digital signal through the integrated metering circuit, and the processor collects the processed current digital signal and the voltage digital signal to perform data calculation and analysis processing, obtaining accurate active and reactive power data and storing the data to a data memory, finally displaying the data by a display and obtaining real-time data, and displaying the working state of the guide rail meter by the light-emitting diode through various switching of on and off states;
the guide rail meter shell comprises a terminal cover and an upper shell matched with the terminal cover, a display mainboard with a display screen and a part of which is exposed at the top of the upper shell is arranged in the upper shell, a relay connecting circuit board is connected below the display mainboard, a power panel with a resistance relay assembly is arranged below the relay connecting circuit board, two terminal seats are arranged on the lower portions of two sides of the power panel, a plurality of zero line copper bars of an access circuit are fixedly arranged below the power panel, the terminal seats are embedded in the lower shell matched with the upper shell, and a plurality of line pressing terminals which are fixed by screws and are installed in a matched mode with the terminal seats are arranged in the lower shell.
Furthermore, the bottom of the bottom shell is also provided with at least one pair of hook springs and hooks correspondingly matched with the hook springs, and the bottom shell is arranged at the installation position of the guide rail meter after the hooks are matched with the hook springs.
Furthermore, communication circuit includes infrared communication device, RS485 communication device, realizes the data transmission of guide rail table and guide rail table peripheral equipment through RS485 communication device and infrared communication device's cooperation, and then realizes data transmission's wireless.
The invention has the beneficial effects that: the invention realizes the collection of current signals by the scheme that the manganin resistor, the sampling signal modulation chip and the isolation pulse transformer are matched with the sampling, compared with the current sampling scheme that the current transformer is adopted in the existing three-phase electric energy meter, the cost of the isolation pulse transformer for isolation and signal coupling is lower in the aspect of application cost, and the total cost of the manganin resistor, the sampling signal modulation chip and the isolation pulse transformer is also lower than the use cost of the current transformer which is commonly used, in particular compared with a plurality of large current transformers, the application cost of the scheme of the invention is far lower than that of a plurality of existing large current transformers, and the volume of the isolation pulse transformer is far lower than that of the current transformer which is commonly used in the aspect of structural volume, so that the volume of the current sampling module of the whole guide rail meter is far lower than that of the current transformer which is commonly used in the existing, and the, the guide rail meter has the advantages that the miniaturization of the meter shell of the guide rail meter is realized, the meter shell material is saved, the production and transportation cost is greatly reduced, the problem that the meter shell is too large due to the fact that the current transformer is large in size and heavy in weight is avoided, in addition, the sampling scheme of the current transformer is not adopted any more, the scheme that the manganin resistor, the sampling signal modulation chip and the isolation pulse transformer are matched for sampling is adopted, the problem that the guide rail meter is affected by strong magnetism to be saturated and the metering is inaccurate can be avoided, the scheme of the invention is not affected by the strong magnetism, and the metering.
Drawings
FIG. 1 is a block diagram of the working principle of a three-phase manganin sampling AC guide rail meter.
Fig. 2 is an assembly diagram of a three-phase manganin sampling alternating current guide rail table.
Fig. 3 is a diagram of a resistance-divided sampling circuit.
The part names numbered in the drawings are as follows: 1. a nameplate; 2. a terminal cover; 3. an upper shell; 4. displaying the main board; 9. displaying a window transparent lens; 10. the relay is connected with the circuit board; 5. a resistance relay assembly; 11. a power panel; 12. a terminal block; 6. a zero line copper bar; 14. a bottom case; 7. a screw; 13. wire pressing terminals; 8. a hook spring; 15. and (4) hanging hooks.
Detailed Description
In order to make the technical means, innovative features and functions of the present invention easy to understand, the present invention will be further described below.
As shown in fig. 1 and 3, the technical solution of the three-phase manganin sampling alternating current guide rail meter of the present invention comprises a guide rail meter housing and a circuit module arranged in the guide rail meter housing, wherein the circuit module comprises a measurement unit, a management control unit, a communication circuit, a power circuit and a function circuit, and the measurement unit, the communication circuit, the power circuit and the function circuit are respectively and electrically connected with the management control unit;
the management control unit comprises a processor, an LCD driver, a real-time clock, a display, a data memory and a light emitting diode, the measuring unit comprises three current sampling modules for the guide rail meter to acquire three-phase current, three resistance voltage division sampling circuits for the guide rail meter to acquire three-phase voltage and an integrated metering circuit working with the processor in a matching way, the current sampling modules comprise a manganin resistor, a sampling signal modulation chip and an isolation pulse transformer, the current connected to the ammeter is subjected to high-speed sampling through the manganin resistor, then is subjected to coupling after sequentially passing through the sampling signal modulation chip and the isolation pulse transformer, is processed and converted into a current digital signal through the integrated metering circuit, the voltage is subjected to sampling through the resistance voltage division sampling circuits and then is processed and converted into a voltage digital signal through the integrated metering circuit, and the processor collects the processed current digital signal and the voltage digital signal to perform data calculation and analysis processing, and obtaining accurate active and reactive power data, storing the data into a data memory, displaying the data by a display and obtaining real-time data, and displaying the working state of the guide rail meter by the light-emitting diode through various switching of on and off states.
When the guide rail meter works, voltage and current accessed to the guide rail meter pass through the resistance voltage division sampling circuit and the current sampling module, are coupled with the isolation pulse transformer through the sampling signal modulation chip and then are sent into the integrated metering circuit, are converted into voltage and current digital signals through the differential amplification circuit of the integrated metering circuit, and finally, the high-performance processor carries out analysis processing on the digital signals to obtain accurate active and reactive electric quantity data, displays the data through LCD driving and display matching, and carries out wireless transmission of the data through the communication circuit.
The processor can also finish time-interval and charge-rate metering of electric energy and demand, record and save instantaneous data and parameters such as voltage, current, power factor and the like to the data memory.
In practical application, the processor can adopt a single chip microcomputer with the models of HT9032C (16DIP) and HT9032D (8DIP), an LCD driver and a display are matched to display voltage and current data which are calculated, analyzed and processed by various microprocessors, the data memory adopts a memory with the models of AT27C256R-70JU, AT27C4096-55JU or AT27C4096-90PU and is used for recording and storing various voltage and current parameters, the light-emitting diode is used for indicating the current state and other information of the guide rail table, and the integrated metering circuit can adopt metering chips with the models of JSY-MK-301, ATT7022B, V9203 and the like to carry out digital processing on the voltage and current data.
The resistance voltage division sampling module is shown in fig. 3, the voltage is processed by the integrated metering circuit and converted into a voltage digital signal after being subjected to resistance voltage division from a zero line, and finally the collected and processed voltage digital signal is subjected to data calculation and analysis processing by the processor.
As shown in fig. 2, in an embodiment of the three-phase manganin sampling alternating current guide rail meter, a guide rail meter case includes a terminal cover 2 and an upper case 3 matched with the terminal cover 2, a display main board 4 with a display screen and partially exposed out of the top of the upper case 3 is arranged in the upper case 3, a relay connection circuit board 10 is connected below the display main board 4, a power board 11 with a resistance relay assembly 5 is arranged below the relay connection circuit board 10, two terminal bases 12 are arranged at lower portions of two sides of the power board 11, a plurality of zero line copper bars 6 connected to a circuit are fixedly arranged below the power board 11, the terminal bases 12 are embedded in a bottom case 14 matched with the upper case 3, and a plurality of line pressing terminals 13 fixed by screws 7 and installed in a matching manner with the terminal bases 12 are arranged in the bottom case 14. Correspondingly, when the guide rail meter shell needs to be installed and positioned, at least one pair of hook springs 8 and hooks 15 correspondingly matched with the hook springs 8 are further arranged at the bottom of the bottom shell 14, and the bottom shell 14 is installed at the installation position of the guide rail meter after the hooks 15 are matched with the hook springs 8. When carrying out the design of guide rail table shell, for the more convenient expression of carrying out each item data of guide rail table self, still installed the data plate at guide rail table shell for the show of guide rail table information covers in the effect that display window transparent lens 9 on display surface can also play the protection display, prevents that the display from accidental damage.
In order to more conveniently and stably carry out the wireless transmission of guide rail table data, the communication unit includes infrared communication device, RS485 communication device, realizes the data transmission of guide rail table and guide rail table external equipment through the cooperation of RS485 communication device and infrared communication device, and then realizes data transmission's wireless ization.
In order to facilitate the normal work of the guide rail meter, a power supply circuit and a functional circuit can be designed in the guide rail meter, the power supply circuit is responsible for providing the guide rail meter with functions, and the functional circuit realizes the connection of other functional components such as keys on the guide rail meter and the like with the guide rail meter circuit.
Although the present invention has been described with reference to the above embodiments, it should be understood that the invention is not limited thereto, and various changes and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention.

Claims (3)

1. The utility model provides a three-phase manganin sampling exchanges guide rail table which characterized in that: the guide rail meter comprises a guide rail meter shell and a circuit module arranged in the guide rail meter shell, wherein the circuit module comprises a measuring unit, a management control unit, a communication circuit, a power supply circuit and a function circuit, and the measuring unit, the communication circuit, the power supply circuit and the function circuit are respectively and electrically connected with the management control unit;
the management control unit comprises a processor, an LCD driver, a real-time clock, a display, a data memory and a light emitting diode, the measuring unit comprises three current sampling modules for the guide rail meter to acquire three-phase current, three resistance voltage division sampling circuits for the guide rail meter to acquire three-phase voltage and an integrated metering circuit working with the processor in a matching way, the current sampling modules comprise a manganin resistor, a sampling signal modulation chip and an isolation pulse transformer, the current connected to the ammeter is subjected to high-speed sampling through the manganin resistor, then is subjected to coupling after sequentially passing through the sampling signal modulation chip and the isolation pulse transformer, is processed and converted into a current digital signal through the integrated metering circuit, the voltage is subjected to sampling through the resistance voltage division sampling circuits and then is processed and converted into a voltage digital signal through the integrated metering circuit, and the processor collects the processed current digital signal and the voltage digital signal to perform data calculation and analysis processing, obtaining accurate active and reactive power data and storing the data to a data memory, finally displaying the data by a display and obtaining real-time data, and displaying the working state of the guide rail meter by the light-emitting diode through various switching of on and off states;
the guide rail meter shell comprises a terminal cover (2) and an upper shell (3) matched with the terminal cover (2), a display main board (4) which is partially exposed at the top of the upper shell (3) and provided with a display screen is arranged in the upper shell (3), a relay connecting circuit board (10) is connected below the display main board (4), a power board (11) with a resistance relay assembly (5) is arranged below the relay connecting circuit board (10), two terminal seats (12) are arranged on the lower portions of two sides of the power board (11), a plurality of zero line copper bars (6) connected with a circuit are fixedly arranged below the power board (11), the terminal seats (12) are embedded into a bottom shell (14) matched with the upper shell (3), and a plurality of line pressing terminals (13) which are fixed by screws (7) and are installed in a matched mode with the terminal seats (12) are arranged in the bottom shell (14).
2. The three-phase manganin sampling alternating current guide rail table according to claim 1, characterized in that: the bottom shell (14) bottom still is equipped with at least a pair of couple spring (8), corresponds complex couple (15) with couple spring (8), make bottom shell (14) install in the mounted position of guide rail table after couple (15) and couple spring (8) cooperation.
3. A three-phase manganin sampling ac rail table according to claim 1 or 2, wherein: the communication circuit comprises an infrared communication device and an RS485 communication device, and data transmission between the guide rail meter and external equipment of the guide rail meter is realized through the cooperation of the RS485 communication device and the infrared communication device, so that wireless data transmission is realized.
CN201911112760.0A 2019-11-14 2019-11-14 Three-phase manganin sampling alternating current guide rail meter Pending CN110794207A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111398670A (en) * 2020-04-20 2020-07-10 南通三本电子有限公司 Three-phase three-wire voltage and current signal acquisition circuit
CN112305282A (en) * 2020-10-10 2021-02-02 浙江晨泰科技股份有限公司 Ammeter with uncap and detect
CN112325462A (en) * 2020-10-11 2021-02-05 浙江晨泰科技股份有限公司 Intelligent air conditioner metering module
CN112332636A (en) * 2020-10-10 2021-02-05 浙江晨泰科技股份有限公司 Guide rail meter with anti-strong magnetic isolation power supply

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CN2689239Y (en) * 2003-12-16 2005-03-30 江苏林洋电子有限公司 Split inputting current sensors
CN2884212Y (en) * 2006-04-03 2007-03-28 杭州华隆电子技术有限公司 Electric power meter by using copper-manganese current-diverter for current sampling
CN201788230U (en) * 2010-07-16 2011-04-06 珠海中慧微电子有限公司 Dual manganin current sampling circuit
CN204287269U (en) * 2014-12-24 2015-04-22 嘉兴东鸿电子科技有限公司 A kind of Multifunctional three-phase electric energy table of direct access
CN204462216U (en) * 2015-03-16 2015-07-08 浙江晨泰科技股份有限公司 A kind of three-phase many rates guide rail meter
CN209296768U (en) * 2018-09-05 2019-08-23 嘉兴市星皓仪表有限公司 Copper-manganese three-phase electric energy meter

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2689239Y (en) * 2003-12-16 2005-03-30 江苏林洋电子有限公司 Split inputting current sensors
CN2884212Y (en) * 2006-04-03 2007-03-28 杭州华隆电子技术有限公司 Electric power meter by using copper-manganese current-diverter for current sampling
CN201788230U (en) * 2010-07-16 2011-04-06 珠海中慧微电子有限公司 Dual manganin current sampling circuit
CN204287269U (en) * 2014-12-24 2015-04-22 嘉兴东鸿电子科技有限公司 A kind of Multifunctional three-phase electric energy table of direct access
CN204462216U (en) * 2015-03-16 2015-07-08 浙江晨泰科技股份有限公司 A kind of three-phase many rates guide rail meter
CN209296768U (en) * 2018-09-05 2019-08-23 嘉兴市星皓仪表有限公司 Copper-manganese three-phase electric energy meter

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111398670A (en) * 2020-04-20 2020-07-10 南通三本电子有限公司 Three-phase three-wire voltage and current signal acquisition circuit
CN112305282A (en) * 2020-10-10 2021-02-02 浙江晨泰科技股份有限公司 Ammeter with uncap and detect
CN112332636A (en) * 2020-10-10 2021-02-05 浙江晨泰科技股份有限公司 Guide rail meter with anti-strong magnetic isolation power supply
CN112325462A (en) * 2020-10-11 2021-02-05 浙江晨泰科技股份有限公司 Intelligent air conditioner metering module

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