CN116087614A - Electric energy meter communication circuit and device - Google Patents
Electric energy meter communication circuit and device Download PDFInfo
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- CN116087614A CN116087614A CN202211604086.XA CN202211604086A CN116087614A CN 116087614 A CN116087614 A CN 116087614A CN 202211604086 A CN202211604086 A CN 202211604086A CN 116087614 A CN116087614 A CN 116087614A
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- module
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- energy meter
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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
- G01R22/06—Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
- G01R22/061—Details of electronic electricity meters
- G01R22/063—Details of electronic electricity meters related to remote communication
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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
- G01R22/06—Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
- G01R22/10—Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods using digital techniques
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D10/00—Energy efficient computing, e.g. low power processors, power management or thermal management
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Abstract
The invention discloses a communication circuit and a device of an electric energy meter, wherein the communication circuit comprises the following components: a power module; a level conversion module; an interface module; a protection circuit; the power supply module is respectively connected with the level conversion module, the interface module and the protection circuit and is used for supplying power to the level conversion module, the interface module and the protection circuit; the level conversion module is connected with the interface module, and converts the downloaded USB data into TTL data and converts the uploaded TTL data into USB data; the protection circuit is connected with the interface module and used for protecting the interface module.
Description
Technical Field
The invention relates to the technical field of electric energy meters, in particular to an electric energy meter communication circuit and device.
Background
When the current electric energy meter is abnormal, the electric power bureau lacks a charging basis, so that the electricity consumption cost of a user can be saved, and the electric energy meter is transferred to an electric energy meter manufacturer under the necessary condition. In the case of data reading, the manufacturer arranges for a technician to go on business or to perform professional disassembly analysis by returning the faulty electric energy meter to the manufacturer. The prior electric energy meter communication device has the following technical problems: 1. after the problems occur, the cost of electricity consumers is avoided, and economic losses are caused for electricity consumers or electricity meter manufacturers. 2. The ammeter manufacturer arranges personnel to go to the site for business trip to read MCU data and analyze the cause of the problem, the economic cost is large, and the site does not have a complete set of problem analysis environment. 3. The power supply customer returns the abnormal electric energy meter to the manufacturer for analysis, the back and forth express time is longer, and the electric energy meter can be generated in the way. And the data read by the manufacturer is not finished under the supervision of the power consumer and the power supply consumer, and the authority is lacking.
Disclosure of Invention
One of the purposes of the invention is to provide a communication circuit and a device of an electric energy meter, wherein a power module and a voltage conversion device are arranged in the circuit and the device, and a low-voltage power supply can be converted into a higher-voltage power supply which accords with the operation of the electric energy meter through the voltage conversion device, so that the electric energy meter can be powered on under the condition that the power supply is disconnected, and a power basis is provided for reading related electric energy meter data.
The invention further aims to provide a circuit and a device for electric energy meter communication, wherein a level conversion module and a USB device are arranged in the circuit and the device, the level conversion module can be used for converting downloaded USB data into TTL data which can be identified by an MCU and converting uploaded TTL data into USB data, so that related data in an electric energy meter can be effectively read, on-site quick reading is realized, and the maintenance time and labor cost of the electric energy meter are reduced.
Another object of the present invention is to provide a communication circuit and apparatus for an electric energy meter, which can supply power and read data of the electric energy meter without damaging the external structure of the electric energy meter, thereby realizing non-invasive and field-supervision-based electric energy meter data reading operation.
In order to achieve at least one of the above objects, the present invention further provides an electric energy meter communication circuit, comprising:
a power module;
a level conversion module;
an interface module;
a protection circuit;
the power supply module is respectively connected with the level conversion module, the interface module and the protection circuit and is used for supplying power to the level conversion module, the interface module and the protection circuit;
the level conversion module is connected with the interface module, and converts the downloaded USB data into TTL data and converts the uploaded TTL data into USB data;
the protection circuit is connected with the interface module and used for protecting the interface module.
According to one preferred embodiment of the present invention, the power module includes a DCDC boost chip, and the power module is connected to an external power source through a USB and boosts an external voltage to a designated voltage through the DCDC boost chip.
According to another preferred embodiment of the present invention, the power module includes an LDO linear regulator, and the LDO linear regulator is connected to an external power supply and configured to step down the external power supply to output a stable voltage.
According to another preferred embodiment of the present invention, a transient suppression diode is connected to the input of the power module, the transient suppression diode is connected in parallel with a plurality of capacitors, and a plurality of capacitors are connected in parallel to the output of the power module.
According to another preferred embodiment of the present invention, the level conversion module includes a TXD pin and a RXD pin connected to corresponding terminals of the interface module, the TXD pin and the RXD pin being used for receiving external power meter related data.
According to another preferred embodiment of the present invention, the level conversion module includes a DM pin and a DP pin, where the DM pin and the DP pin are connected to the data acquisition and transmission terminal, and are used for transmitting the corresponding data converted by the level conversion module.
According to another preferred embodiment of the present invention, the protection circuit includes an interface protection circuit and a current limiting protection circuit, wherein the interface protection circuit is connected to each interface terminal.
According to another preferred embodiment of the present invention, the interface protection circuit includes: the TXD pin and the RXD pin are respectively connected with a transient suppression diode and a capacitor, wherein the transient suppression diode and the capacitor connected with the TXD pin and the RXD pin are connected in parallel.
According to another preferred embodiment of the present invention, the current limiting protection circuit includes a first triode and a second triode, wherein a collector of the first triode is connected to a terminal of the interface module through a forward diode, and a first triode emission set is connected to a collector of the first triode through a resistor; the base of the first triode is connected with the collector of the second triode, the emitter of the second triode is connected with a power supply, and the base of the second triode is connected with the emitter of the first triode through a resistor.
In order to achieve at least one of the above objects, the present invention further provides an electric energy meter communication device, comprising:
a first circuit board;
a second circuit board;
a USB interface;
a probe;
a housing;
the interface module on the first circuit board is connected with a USB interface through a wire to a corresponding DM pin and a DP pin of the input end of the level conversion module, the interface module on the second circuit board is connected with a TXD pin and a RXD pin corresponding to the output end of the level conversion module through a wire, and the interface module on the second circuit board is connected with the corresponding TXD pin and RXD pin to a corresponding probe through the interface module on the second circuit board.
Drawings
Fig. 1 is a schematic diagram of an overall module of a communication circuit of an electric energy meter according to the present invention.
Fig. 2 is a schematic diagram of a power module of the communication circuit of the electric energy meter according to the present invention.
Fig. 3 is a schematic circuit diagram of a level shift module according to the present invention.
Fig. 4 is a schematic diagram showing the structural arrangement of the interface module in the present invention.
Fig. 5 shows a schematic diagram of an interface protection circuit for protecting a module according to the present invention.
Fig. 6 shows a schematic diagram of an interface current limiting circuit of the protection module of the present invention.
Fig. 7 shows an exploded view of a communication device for an electric energy meter according to the present invention.
Wherein, the shell-10, the plug 11, the plug bottom board-111, the plug cover-112, the probe-20, the first circuit board-31, the second circuit board-32 and the USB interface-40
Detailed Description
The following description is presented to enable one of ordinary skill in the art to make and use the invention. The preferred embodiments in the following description are by way of example only and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.
It will be understood that the terms "a" and "an" should be interpreted as referring to "at least one" or "one or more," i.e., in one embodiment, the number of elements may be one, while in another embodiment, the number of elements may be plural, and the term "a" should not be interpreted as limiting the number.
Referring to fig. 1-7, the invention discloses a communication circuit and a device for an electric energy meter, wherein the communication circuit comprises: a power module; a level conversion module; an interface module; a protection circuit; the power supply module comprises a DCDC boosting device and an LDO linear voltage stabilizing circuit, wherein the DCDC boosting device is used for boosting a power supply with lower external voltage to a voltage meeting the requirements of the electric energy meter, and the output end of the LDO linear voltage stabilizing circuit is used for supplying power to the level conversion module in an analog stable mode. The level conversion circuit is a bidirectional conversion circuit, and can be used for converting uplink TTL data into USB data, and the USB data can be uploaded to a PC end through a USB cable for analysis and display. The level conversion circuit can be used for converting the downlink USB data of the PC end into TTL data which can be identified by the MCU of the electric energy meter, so that bidirectional data reading interaction can be realized by the level conversion circuit, and the influence of a data format barrier on data reading is avoided. The protection circuit comprises an interface protection circuit and an interface current limiting circuit, wherein the interface protection circuit and the interface current limiting circuit can be simultaneously installed and connected with terminals corresponding to the interface module.
Specifically, please refer to the power module schematic diagram shown in fig. 2, wherein the power module includes two parts, the first part is a DCDC boost part configured with an MP1542DK chip, wherein an input end of the MP1542DK chip is connected to a USB input voltage 5V of a PC end, a transient suppression diode (TVS 3) and a plurality of capacitors (C9, C3P, C P) connected in parallel are further connected to the input end, and the other end of the capacitor C9 is grounded. The MP1542DK chip comprises an EN pin (enabling pin), an FSEL pin (frequency selection pin), an FB pin (feedback pin), an SS pin (soft start pin) and a COMP pin (compensation pin), wherein the EN pin is connected with an input power supply after being connected in parallel through a resistor (R1P), the FSEL pin is connected with the input power supply after being connected in parallel through a resistor (R7P), the SS pin is grounded after being connected through a capacitor (C6P), and the COMP pin is grounded after being connected with the resistor (R4P). The FB pin is connected with two resistors (R2P and R3P) in parallel and then respectively grounded and connected with the output end. The output end of the MP1542DK chip outputs a 15V boosted voltage, and the output end of the MP1542DK chip is connected with three capacitors (C5P, C P and C6P) in parallel and grounded.
Referring to the lower left part of fig. 2, the second part of the power module is an SGM2203-3.3YK3G chip, the SGM2203-3.3YK3G chip is an LDO linear voltage stabilizing chip, the chip is connected to an input power source (5V), and outputs a stable 3.3V voltage at the output end of the SGM2203-3.3YK3G chip, where the voltage output by the output end of the SGM2203-3.3YK3G chip is connected to an MP1542DK chip for supplying power thereto. The input end of the SGM2203-3.3YK3G chip is connected with a capacitor (C145) in parallel and then grounded, and the output end of the SGM2203-3.3YK3G chip is connected with a capacitor (C146) in parallel and then grounded. Referring to the lower right part of fig. 2, the power module is connected to the USB interface of the PC end through a VBUS power supply line, and is connected to the input ends of the first and second parts of the power module.
Referring to fig. 3, a schematic circuit structure of a level conversion module according to the present invention is shown, wherein a PL2303 chip is preferably used as a USB bidirectional converter of the level conversion module, a TXD pin and a RXD pin in the PL2303 chip are used as output pins, TTL related data is sent and received to an electric energy meter, a DM pin and a DP pin in the PL2303 chip are corresponding USB interface related pins, and are used for transmitting USB related data, and vdd_325 of the PL2303 chip in the present invention is used as a power supply pin, and the pin is connected to an output end of the second portion of the power module, where an output voltage is 3.3V. Rst_n is the reset pin, OSC1 and OSC2 are the oscillator pins, respectively. Because the connection of the TXD pin, the RXD pin, the DM pin and the DP pin is limited in practice, other pins of the PL2303 chip in the invention are not described in detail, and only the pin connection mode of the corresponding USB bidirectional conversion function is realized. The TXD pin, the RXD pin DM pin and the DP pin are connected with an interface module and used for data transmission.
Referring to fig. 4 and 7, the interface module of the present invention is provided with two parts, and is respectively mounted on the first circuit board and the second circuit board, the interface module on the first circuit board connects the USB interface to the corresponding DM pin and DP pin of the input end of the level conversion module through wires, the interface module on the second circuit board connects the corresponding TXD pin and RXD pin of the output end of the level conversion module through wires, and connects the corresponding TXD pin and RXD pin to the corresponding probe through the interface module on the second circuit board. The first circuit board is configured with a power module and a level conversion module according to the connection mode. And a protection circuit is further configured to realize safe and stable USB bidirectional conversion data transmission.
It should be noted that, referring to fig. 5 and fig. 6, the present invention discloses two parts of the protection circuit, namely an interface protection circuit and a current limiting protection circuit, wherein the TXD pin and the RXD pin are both connected with one interface protection circuit, the interface protection circuit connected with the TXD pin comprises a transient suppression diode (TVS 1) and a capacitor (C4) connected in parallel, and the interface protection circuit connected with the RXD pin comprises a transient suppression diode (TVS 2) and a capacitor (C5) connected in parallel. The current limiting protection circuit includes: the first triode (Q6) and the second triode (Q11), wherein the collector electrode of the first triode is connected with the terminal of the interface module through a forward diode (D1), and the emission set of the first triode is connected with the collector electrode of the first triode through a resistor (R31); the base of the first triode is connected with the collector of the second triode, the emitter of the second triode is connected with a power supply, and the base of the second triode is connected with the emitter of the first triode through a resistor (R34).
With reference to fig. 7, the invention provides an explosion schematic diagram of an electric energy meter communication device, which is provided with two circuit boards, wherein a first circuit board is connected with a USB interface through an interface module, the USB interface is connected with an upper computer, the first circuit board is installed according to the connection mode among the power module, the level conversion module, the interface module and the protection circuit, the interface module on the second circuit board is connected with a TXD pin and a RXD pin corresponding to the output end of the level conversion module through wires, and the interface module on the second circuit board is connected with the corresponding TXD pin and RXD pin to the corresponding probe. The electric energy meter communication device is provided with a shell, the shell comprises a plug, the probe extends out through the plug, and the plug comprises a plug cover and a plug bottom plate.
In particular, according to embodiments of the present disclosure, the processes described above with reference to flowcharts may be implemented as computer software programs. For example, embodiments of the present disclosure include a computer program product comprising a computer program embodied on a computer readable medium, the computer program comprising program code for performing the method shown in the flowcharts. In such embodiments, the computer program may be downloaded and installed from a network via a communication portion, and/or installed from a removable medium. The above-described functions defined in the method of the present application are performed when the computer program is executed by a Central Processing Unit (CPU). It should be noted that the computer readable medium described in the present application may be a computer readable signal medium or a computer readable storage medium, or any combination of the two. The computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wire segments, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. In the present application, however, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, with computer-readable program code embodied therein. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination of the foregoing. A computer readable signal medium may also be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wire, fiber optic cable, RF, etc., or any suitable combination of the foregoing.
The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
It will be understood by those skilled in the art that the embodiments of the present invention described above and shown in the drawings are merely illustrative and not restrictive of the current invention, and that this invention has been shown and described with respect to the functional and structural principles thereof, without departing from such principles, and that any modifications or adaptations of the embodiments of the invention may be possible and practical.
Claims (10)
1. An electric energy meter communication circuit, comprising:
a power module;
a level conversion module;
an interface module;
a protection circuit;
the power supply module is respectively connected with the level conversion module, the interface module and the protection circuit and is used for supplying power to the level conversion module, the interface module and the protection circuit;
the level conversion module is connected with the interface module, and converts the downloaded USB data into TTL data and converts the uploaded TTL data into USB data;
the protection circuit is connected with the interface module and used for protecting the interface module.
2. The electric energy meter communication circuit of claim 1, wherein the power module comprises a DCDC boost chip, wherein the power module is connected to an external power source via a USB and boosts an external voltage to a specified voltage via the DCDC boost chip.
3. The electric energy meter communication circuit of claim 1, wherein the power module comprises an LDO linear voltage regulator, the LDO linear voltage regulator is connected to an external power supply, and is configured to step down the external power supply to output a stable voltage.
4. The electrical energy meter communication circuit of claim 1, wherein a transient suppression diode is connected to the input of the power module, the transient suppression diode is connected in parallel with a plurality of capacitors, and a plurality of capacitors are connected in parallel to the output of the power module.
5. The electrical energy meter communication circuit of claim 1, wherein the level shifting module includes TXD pins and RXD pins coupled to corresponding terminals of the interface module, the TXD pins and RXD pins configured to receive external electrical energy meter related data.
6. The electric energy meter communication circuit of claim 5, wherein the level conversion module comprises a DM pin and a DP pin, wherein the DM pin and the DP pin are connected to the data acquisition and transmission terminal for transmitting the corresponding data converted by the level conversion module.
7. The electrical energy meter communication circuit of claim 1, wherein the protection circuit comprises an interface protection circuit and a current limiting protection circuit, wherein the interface protection circuit is connected to each interface terminal.
8. The electrical energy meter communication circuit of claim 5, wherein the interface protection circuit comprises: the TXD pin and the RXD pin are respectively connected with a transient suppression diode and a capacitor, wherein the transient suppression diode and the capacitor connected with the TXD pin and the RXD pin are connected in parallel.
9. The electric energy meter communication circuit of claim 7, wherein the current limiting protection circuit comprises a first triode and a second triode, wherein a collector of the first triode is connected with an interface module terminal through a forward diode, and a first triode emission set is connected with a collector of the first triode through a resistor; the base of the first triode is connected with the collector of the second triode, the emitter of the second triode is connected with a power supply, and the base of the second triode is connected with the emitter of the first triode through a resistor.
10. An electric energy meter communication device, characterized in that the communication device comprises:
a first circuit board;
a second circuit board;
a USB interface;
a probe;
a housing;
the interface module on the first circuit board is connected with a USB interface through a wire to a corresponding DM pin and a DP pin of the input end of the level conversion module, the interface module on the second circuit board is connected with a TXD pin and a RXD pin corresponding to the output end of the level conversion module through a wire, and the interface module on the second circuit board is connected with the corresponding TXD pin and RXD pin to a corresponding probe through the interface module on the second circuit board.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211604086.XA CN116087614A (en) | 2022-12-13 | 2022-12-13 | Electric energy meter communication circuit and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211604086.XA CN116087614A (en) | 2022-12-13 | 2022-12-13 | Electric energy meter communication circuit and device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116087614A true CN116087614A (en) | 2023-05-09 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211604086.XA Pending CN116087614A (en) | 2022-12-13 | 2022-12-13 | Electric energy meter communication circuit and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116087614A (en) |
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2022
- 2022-12-13 CN CN202211604086.XA patent/CN116087614A/en active Pending
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